Version bump for 0.75 release (#7902)

- [x] Are we ready for the release
- [x] Upgrade to upcoming `reedline 0.15`

.github/dependabot.yml

@@ -0,0 +1,20 @@
+# To get started with Dependabot version updates, you'll need to specify which
+# package ecosystems to update and where the package manifests are located.
+# Please see the documentation for all configuration options:
+# https://docs.github.com/github/administering-a-repository/configuration-options-for-dependency-updates
+
+# docs
+# https://docs.github.com/en/code-security/dependabot/dependabot-version-updates/configuration-options-for-the-dependabot.yml-file
+version: 2
+updates:
+  - package-ecosystem: "cargo"
+    directory: "/"
+    schedule:
+      interval: "weekly"
+    ignore:
+      - dependency-name: "*"
+        update-types: ["version-update:semver-patch"]
+  - package-ecosystem: "github-actions"
+    directory: "/"
+    schedule:
+      interval: "weekly"

.github/workflows/ci.yml

@@ -15,8 +15,22 @@ jobs:
         # builds to link against a too-new-for-many-Linux-installs glibc version. Consider
         # revisiting this when 20.04 is closer to EOL (April 2025)
         platform: [windows-latest, macos-latest, ubuntu-20.04]
+        style: [default, dataframe]
         rust:
           - stable
+        include:
+          - style: default
+            flags: ""
+          - style: dataframe
+            flags: "--features=dataframe "
+        exclude:
+          # only test dataframes on Ubuntu (the fastest platform)
+          - platform: windows-latest
+            style: dataframe
+          - platform: macos-latest
+            style: dataframe
+
+
 
     runs-on: ${{ matrix.platform }}
     env:
@@ -26,13 +40,13 @@ jobs:
       - uses: actions/checkout@v3
 
       - name: Setup Rust toolchain and cache
-        uses: actions-rust-lang/setup-rust-toolchain@v1.3.4
+        uses: actions-rust-lang/setup-rust-toolchain@v1.3.5
 
       - name: cargo fmt
         run: cargo fmt --all -- --check
 
       - name: Clippy
-        run: cargo clippy --workspace --exclude nu_plugin_* -- -D warnings -D clippy::unwrap_used -A clippy::needless_collect
+        run: cargo clippy --workspace ${{ matrix.flags }}--exclude nu_plugin_* -- -D warnings -D clippy::unwrap_used -A clippy::needless_collect
 
   nu-tests:
     env:
@@ -63,7 +77,7 @@ jobs:
       - uses: actions/checkout@v3
 
       - name: Setup Rust toolchain and cache
-        uses: actions-rust-lang/setup-rust-toolchain@v1.3.4
+        uses: actions-rust-lang/setup-rust-toolchain@v1.3.5
 
       - name: Tests
         run: cargo test --workspace --profile ci --exclude nu_plugin_* ${{ matrix.flags }}
@@ -87,7 +101,7 @@ jobs:
       - uses: actions/checkout@v3
 
       - name: Setup Rust toolchain and cache
-        uses: actions-rust-lang/setup-rust-toolchain@v1.3.4
+        uses: actions-rust-lang/setup-rust-toolchain@v1.3.5
 
       - name: Install Nushell
         run: cargo install --locked --path=. --profile ci --no-default-features
@@ -99,8 +113,9 @@ jobs:
 
       - run: python -m pip install tox
 
+        # Get only the latest tagged version for stability reasons
       - name: Install virtualenv
-        run: git clone https://github.com/pypa/virtualenv.git
+        run: git clone https://github.com/pypa/virtualenv.git && cd virtualenv && git checkout $(git describe --tags | cut -d - -f 1)
         shell: bash
 
       - name: Test Nushell in virtualenv
@@ -126,7 +141,7 @@ jobs:
       - uses: actions/checkout@v3
 
       - name: Setup Rust toolchain and cache
-        uses: actions-rust-lang/setup-rust-toolchain@v1.3.4
+        uses: actions-rust-lang/setup-rust-toolchain@v1.3.5
 
       - name: Clippy
         run: cargo clippy --package nu_plugin_* ${{ matrix.flags }} -- -D warnings -D clippy::unwrap_used -A clippy::needless_collect

.github/workflows/release-pkg.nu

@@ -7,18 +7,29 @@
 #   1. https://github.com/volks73/cargo-wix
 
 # Added 2022-11-29 when Windows packaging wouldn't work
-# because softprops/action-gh-release was broken
 # To run this manual for windows
+# unset CARGO_TARGET_DIR if set
+# hide-env CARGO_TARGET_DIR
 # let-env TARGET = 'x86_64-pc-windows-msvc'
 # let-env TARGET_RUSTFLAGS = ''
 # let-env GITHUB_WORKSPACE = 'C:\Users\dschroeder\source\repos\forks\nushell'
+# let-env GITHUB_OUTPUT = 'C:\Users\dschroeder\source\repos\forks\nushell\output\out.txt'
+# let-env OS = 'windows-latest'
+# You need to run this twice. The first pass makes the output folder and builds everything
+# The second pass generates the msi file
 # Pass 1 let-env _EXTRA_ = 'bin'
 # Pass 2 let-env _EXTRA_ = 'msi'
 # make sure 7z.exe is in your path https://www.7-zip.org/download.html
+# let-env Path = ($env.Path | append 'c:\apps\7-zip')
 # make sure aria2c.exe is in your path https://github.com/aria2/aria2
+# let-env Path = ($env.Path | append 'c:\path\to\aria2c')
 # make sure you have the wixtools installed https://wixtoolset.org/
-# set os below like this because it's what github's runner is named
-# let os = 'windows-latest'
+# let-env Path = ($env.Path | append 'C:\Users\dschroeder\AppData\Local\tauri\WixTools')
+# After msi is generated, if you have to update winget-pkgs repo, you'll need to patch the release
+# by deleting the existing msi and uploading this new msi. Then you'll need to update the hash
+# on the winget-pkgs PR. To generate the hash, run this command
+# open target\wix\nu-0.74.0-x86_64-pc-windows-msvc.msi | hash sha256
+# Then, just take the output and put it in the winget-pkgs PR for the hash on the msi
 
 
 # The main binary file to be released

.github/workflows/release.yml

@@ -70,7 +70,7 @@ jobs:
         echo "targets = ['${{matrix.target}}']" >> rust-toolchain.toml
 
     - name: Setup Rust toolchain and cache
-      uses: actions-rust-lang/setup-rust-toolchain@v1.3.4
+      uses: actions-rust-lang/setup-rust-toolchain@v1.3.5
 
     - name: Setup Nushell
       uses: hustcer/setup-nu@v3

.github/workflows/stale.yml

@@ -12,7 +12,7 @@ jobs:
   stale:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/stale@v3
+      - uses: actions/stale@v6
         with:
           #debug-only: true
           ascending: true

.github/workflows/typos.yml

@@ -0,0 +1,13 @@
+name: Typos
+on: [pull_request]
+
+jobs:
+  run:
+    name: Spell Check with Typos
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout Actions Repository
+        uses: actions/checkout@v2
+
+      - name: Check spelling of book
+        uses: crate-ci/typos@master

.typos.toml

@@ -0,0 +1,12 @@
+[files]
+extend-exclude = ["crates/nu-command/tests/commands/table.rs", "*.tsv", "*.json", "*.txt"]
+
+[default.extend-words]
+# Ignore false-positives
+nd = "nd"
+fo = "fo"
+ons = "ons"
+ba = "ba"
+Plasticos = "Plasticos"
+IIF = "IIF"
+numer = "numer"

Cargo.toml

@@ -3,14 +3,14 @@ authors = ["The Nushell Project Developers"]
 default-run = "nu"
 description = "A new type of shell"
 documentation = "https://www.nushell.sh/book/"
-edition = "2018"
+edition = "2021"
 exclude = ["images"]
 homepage = "https://www.nushell.sh"
 license = "MIT"
 name = "nu"
 repository = "https://github.com/nushell/nushell"
 rust-version = "1.60"
-version = "0.73.0"
+version = "0.75.0"
 
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
@@ -43,25 +43,25 @@ chrono = { version = "0.4.23", features = ["serde"] }
 crossterm = "0.24.0"
 ctrlc = "3.2.1"
 log = "0.4"
-miette = { version = "5.1.0", features = ["fancy-no-backtrace"] }
+miette = { version = "5.5.0", features = ["fancy-no-backtrace"] }
 nu-ansi-term = "0.46.0"
-nu-cli = { path="./crates/nu-cli", version = "0.73.0"  }
-nu-color-config = { path = "./crates/nu-color-config", version = "0.73.0"  }
-nu-command = { path="./crates/nu-command", version = "0.73.0"  }
-nu-engine = { path="./crates/nu-engine", version = "0.73.0"  }
-nu-json = { path="./crates/nu-json", version = "0.73.0"  }
-nu-parser = { path="./crates/nu-parser", version = "0.73.0"  }
-nu-path = { path="./crates/nu-path", version = "0.73.0"  }
-nu-plugin = { path = "./crates/nu-plugin", optional = true, version = "0.73.0"  }
-nu-pretty-hex = { path = "./crates/nu-pretty-hex", version = "0.73.0"  }
-nu-protocol = { path = "./crates/nu-protocol", version = "0.73.0"  }
-nu-system = { path = "./crates/nu-system", version = "0.73.0" }
-nu-table = { path = "./crates/nu-table", version = "0.73.0"  }
-nu-term-grid = { path = "./crates/nu-term-grid", version = "0.73.0"  }
-nu-utils = { path = "./crates/nu-utils", version = "0.73.0"  }
-reedline = { version = "0.14.0", features = ["bashisms", "sqlite"]}
+nu-cli = { path = "./crates/nu-cli", version = "0.75.0" }
+nu-color-config = { path = "./crates/nu-color-config", version = "0.75.0" }
+nu-command = { path = "./crates/nu-command", version = "0.75.0" }
+nu-engine = { path = "./crates/nu-engine", version = "0.75.0" }
+nu-json = { path = "./crates/nu-json", version = "0.75.0" }
+nu-parser = { path = "./crates/nu-parser", version = "0.75.0" }
+nu-path = { path = "./crates/nu-path", version = "0.75.0" }
+nu-plugin = { path = "./crates/nu-plugin", optional = true, version = "0.75.0" }
+nu-pretty-hex = { path = "./crates/nu-pretty-hex", version = "0.75.0" }
+nu-protocol = { path = "./crates/nu-protocol", version = "0.75.0" }
+nu-system = { path = "./crates/nu-system", version = "0.75.0" }
+nu-table = { path = "./crates/nu-table", version = "0.75.0" }
+nu-term-grid = { path = "./crates/nu-term-grid", version = "0.75.0" }
+nu-utils = { path = "./crates/nu-utils", version = "0.75.0" }
+reedline = { version = "0.15.0", features = ["bashisms", "sqlite"] }
 
-rayon = "1.5.1"
+rayon = "1.6.1"
 is_executable = "1.0.1"
 simplelog = "0.12.0"
 time = "0.3.12"
@@ -80,17 +80,25 @@ nix = { version = "0.25", default-features = false, features = ["signal", "proce
 atty = "0.2"
 
 [dev-dependencies]
-nu-test-support = { path="./crates/nu-test-support", version = "0.73.0"  }
+nu-test-support = { path = "./crates/nu-test-support", version = "0.75.0" }
 tempfile = "3.2.0"
 assert_cmd = "2.0.2"
+criterion = "0.4"
 pretty_assertions = "1.0.0"
-serial_test = "0.8.0"
+serial_test = "1.0.0"
 hamcrest2 = "0.3.0"
 rstest = { version = "0.15.0", default-features = false }
 itertools = "0.10.3"
 
 [features]
-plugin = ["nu-plugin", "nu-cli/plugin", "nu-parser/plugin", "nu-command/plugin", "nu-protocol/plugin", "nu-engine/plugin"]
+plugin = [
+	"nu-plugin",
+	"nu-cli/plugin",
+	"nu-parser/plugin",
+	"nu-command/plugin",
+	"nu-protocol/plugin",
+	"nu-engine/plugin",
+]
 # extra used to be more useful but now it's the same as default. Leaving it in for backcompat with existing build scripts
 extra = ["default"]
 default = ["plugin", "which-support", "trash-support", "sqlite"]
@@ -140,3 +148,10 @@ path = "src/main.rs"
 # changing versions in each sub-crate of the workspace is tedious
 [patch.crates-io]
 # reedline = { git = "https://github.com/nushell/reedline.git", branch = "main" }
+
+# Criterion benchmarking setup
+# Run all benchmarks with `cargo bench`
+# Run individual benchmarks like `cargo bench -- <regex>` e.g. `cargo bench -- parse`
+[[bench]]
+name = "benchmarks"
+harness = false

Cross.toml

@@ -0,0 +1,9 @@
+# Configuration for cross-rs: https://github.com/cross-rs/cross
+# Run cross-rs like this:
+# cross build --target aarch64-unknown-linux-musl --release
+
+[target.aarch64-unknown-linux-gnu]
+dockerfile = "./docker/cross-rs/aarch64-unknown-linux-gnu.dockerfile"
+
+[target.aarch64-unknown-linux-musl]
+dockerfile = "./docker/cross-rs/aarch64-unknown-linux-musl.dockerfile"

README.md

@@ -47,7 +47,7 @@ brew install nushell
 winget install nushell
 ```
 
-To use `Nu` in Github Action, check [setup-nu](https://github.com/marketplace/actions/setup-nu) for more detail.
+To use `Nu` in GitHub Action, check [setup-nu](https://github.com/marketplace/actions/setup-nu) for more detail.
 
 Detailed installation instructions can be found in the [installation chapter of the book](https://www.nushell.sh/book/installation.html). Nu is available via many package managers:
 
@@ -174,6 +174,8 @@ These binaries interact with nu via a simple JSON-RPC protocol where the command
 If the plugin is a filter, data streams to it one element at a time, and it can stream data back in return via stdin/stdout.
 If the plugin is a sink, it is given the full vector of final data and is given free reign over stdin/stdout to use as it pleases.
 
+The [awesome-nu repo](https://github.com/nushell/awesome-nu#plugins) lists a variety of nu-plugins.
+
 ## Goals
 
 Nu adheres closely to a set of goals that make up its design philosophy. As features are added, they are checked against these goals.

benches/README.md

@@ -0,0 +1,7 @@
+# Criterion benchmarks
+
+These are benchmarks using [Criterion](https://github.com/bheisler/criterion.rs), a microbenchmarking tool for Rust.
+
+Run all benchmarks with `cargo bench`
+
+Or run individual benchmarks like `cargo bench -- <regex>` e.g. `cargo bench -- parse`

benches/benchmarks.rs

@@ -0,0 +1,187 @@
+use criterion::{criterion_group, criterion_main, BatchSize, Criterion};
+use nu_cli::eval_source;
+use nu_parser::parse;
+use nu_plugin::{EncodingType, PluginResponse};
+use nu_protocol::{PipelineData, Span, Value};
+use nu_utils::{get_default_config, get_default_env};
+
+// FIXME: All benchmarks live in this 1 file to speed up build times when benchmarking.
+// When the *_benchmarks functions were in different files, `cargo bench` would build
+// an executable for every single one - incredibly slowly. Would be nice to figure out
+// a way to split things up again.
+
+fn parser_benchmarks(c: &mut Criterion) {
+    let mut engine_state = nu_command::create_default_context();
+    // parsing config.nu breaks without PWD set
+    engine_state.add_env_var(
+        "PWD".into(),
+        Value::string("/some/dir".to_string(), Span::test_data()),
+    );
+
+    let default_env = get_default_env().as_bytes();
+    c.bench_function("parse_default_env_file", |b| {
+        b.iter_batched(
+            || nu_protocol::engine::StateWorkingSet::new(&engine_state),
+            |mut working_set| parse(&mut working_set, None, default_env, false, &[]),
+            BatchSize::SmallInput,
+        )
+    });
+
+    let default_config = get_default_config().as_bytes();
+    c.bench_function("parse_default_config_file", |b| {
+        b.iter_batched(
+            || nu_protocol::engine::StateWorkingSet::new(&engine_state),
+            |mut working_set| parse(&mut working_set, None, default_config, false, &[]),
+            BatchSize::SmallInput,
+        )
+    });
+
+    c.bench_function("eval default_env.nu", |b| {
+        b.iter(|| {
+            let mut engine_state = nu_command::create_default_context();
+            let mut stack = nu_protocol::engine::Stack::new();
+            eval_source(
+                &mut engine_state,
+                &mut stack,
+                get_default_env().as_bytes(),
+                "default_env.nu",
+                PipelineData::empty(),
+            )
+        })
+    });
+
+    c.bench_function("eval default_config.nu", |b| {
+        b.iter(|| {
+            let mut engine_state = nu_command::create_default_context();
+            // parsing config.nu breaks without PWD set
+            engine_state.add_env_var(
+                "PWD".into(),
+                Value::string("/some/dir".to_string(), Span::test_data()),
+            );
+            let mut stack = nu_protocol::engine::Stack::new();
+            eval_source(
+                &mut engine_state,
+                &mut stack,
+                get_default_config().as_bytes(),
+                "default_config.nu",
+                PipelineData::empty(),
+            )
+        })
+    });
+}
+
+fn eval_benchmarks(c: &mut Criterion) {
+    c.bench_function("eval default_env.nu", |b| {
+        b.iter(|| {
+            let mut engine_state = nu_command::create_default_context();
+            let mut stack = nu_protocol::engine::Stack::new();
+            eval_source(
+                &mut engine_state,
+                &mut stack,
+                get_default_env().as_bytes(),
+                "default_env.nu",
+                PipelineData::empty(),
+            )
+        })
+    });
+
+    c.bench_function("eval default_config.nu", |b| {
+        b.iter(|| {
+            let mut engine_state = nu_command::create_default_context();
+            // parsing config.nu breaks without PWD set
+            engine_state.add_env_var(
+                "PWD".into(),
+                Value::string("/some/dir".to_string(), Span::test_data()),
+            );
+            let mut stack = nu_protocol::engine::Stack::new();
+            eval_source(
+                &mut engine_state,
+                &mut stack,
+                get_default_config().as_bytes(),
+                "default_config.nu",
+                PipelineData::empty(),
+            )
+        })
+    });
+}
+
+// generate a new table data with `row_cnt` rows, `col_cnt` columns.
+fn encoding_test_data(row_cnt: usize, col_cnt: usize) -> Value {
+    let columns: Vec<String> = (0..col_cnt).map(|x| format!("col_{x}")).collect();
+    let vals: Vec<Value> = (0..col_cnt as i64).map(Value::test_int).collect();
+
+    Value::List {
+        vals: (0..row_cnt)
+            .map(|_| Value::test_record(columns.clone(), vals.clone()))
+            .collect(),
+        span: Span::test_data(),
+    }
+}
+
+fn encoding_benchmarks(c: &mut Criterion) {
+    let mut group = c.benchmark_group("Encoding");
+    let test_cnt_pairs = [
+        (100, 5),
+        (100, 10),
+        (100, 15),
+        (1000, 5),
+        (1000, 10),
+        (1000, 15),
+        (10000, 5),
+        (10000, 10),
+        (10000, 15),
+    ];
+    for (row_cnt, col_cnt) in test_cnt_pairs.into_iter() {
+        for fmt in ["json", "msgpack"] {
+            group.bench_function(&format!("{fmt} encode {row_cnt} * {col_cnt}"), |b| {
+                let mut res = vec![];
+                let test_data =
+                    PluginResponse::Value(Box::new(encoding_test_data(row_cnt, col_cnt)));
+                let encoder = EncodingType::try_from_bytes(fmt.as_bytes()).unwrap();
+                b.iter(|| encoder.encode_response(&test_data, &mut res))
+            });
+        }
+    }
+    group.finish();
+}
+
+fn decoding_benchmarks(c: &mut Criterion) {
+    let mut group = c.benchmark_group("Decoding");
+    let test_cnt_pairs = [
+        (100, 5),
+        (100, 10),
+        (100, 15),
+        (1000, 5),
+        (1000, 10),
+        (1000, 15),
+        (10000, 5),
+        (10000, 10),
+        (10000, 15),
+    ];
+    for (row_cnt, col_cnt) in test_cnt_pairs.into_iter() {
+        for fmt in ["json", "msgpack"] {
+            group.bench_function(&format!("{fmt} decode for {row_cnt} * {col_cnt}"), |b| {
+                let mut res = vec![];
+                let test_data =
+                    PluginResponse::Value(Box::new(encoding_test_data(row_cnt, col_cnt)));
+                let encoder = EncodingType::try_from_bytes(fmt.as_bytes()).unwrap();
+                encoder.encode_response(&test_data, &mut res).unwrap();
+                let mut binary_data = std::io::Cursor::new(res);
+                b.iter(|| {
+                    binary_data.set_position(0);
+                    encoder.decode_response(&mut binary_data)
+                })
+            });
+        }
+    }
+    group.finish();
+}
+
+criterion_group!(
+    benches,
+    parser_benchmarks,
+    eval_benchmarks,
+    encoding_benchmarks,
+    decoding_benchmarks
+);
+criterion_main!(benches);

build-all-windows.cmd

@@ -5,7 +5,7 @@
 @echo.
 
 echo Building nushell.exe
-cargo build cargo build --features=dataframe
+cargo build --features=dataframe
 @echo.
 
 @cd crates\nu_plugin_example

crates/nu-cli/Cargo.toml

@@ -5,34 +5,34 @@ repository = "https://github.com/nushell/nushell/tree/main/crates/nu-cli"
 edition = "2021"
 license = "MIT"
 name = "nu-cli"
-version = "0.73.0"
+version = "0.75.0"
 
 [dev-dependencies]
-nu-test-support = { path="../nu-test-support", version = "0.73.0"  }
-nu-command = { path = "../nu-command", version = "0.73.0" }
+nu-test-support = { path = "../nu-test-support", version = "0.75.0" }
+nu-command = { path = "../nu-command", version = "0.75.0" }
 rstest = { version = "0.15.0", default-features = false }
 
 [dependencies]
-nu-engine = { path = "../nu-engine", version = "0.73.0"  }
-nu-path = { path = "../nu-path", version = "0.73.0"  }
-nu-parser = { path = "../nu-parser", version = "0.73.0"  }
-nu-protocol = { path = "../nu-protocol", version = "0.73.0"  }
-nu-utils = { path = "../nu-utils", version = "0.73.0"  }
+nu-engine = { path = "../nu-engine", version = "0.75.0" }
+nu-path = { path = "../nu-path", version = "0.75.0" }
+nu-parser = { path = "../nu-parser", version = "0.75.0" }
+nu-protocol = { path = "../nu-protocol", version = "0.75.0" }
+nu-utils = { path = "../nu-utils", version = "0.75.0" }
 nu-ansi-term = "0.46.0"
-nu-color-config = { path = "../nu-color-config", version = "0.73.0"  }
-reedline = { version = "0.14.0", features = ["bashisms", "sqlite"]}
+nu-color-config = { path = "../nu-color-config", version = "0.75.0" }
+reedline = { version = "0.15.0", features = ["bashisms", "sqlite"] }
 
 atty = "0.2.14"
 chrono = { default-features = false, features = ["std"], version = "0.4.23" }
 crossterm = "0.24.0"
-fancy-regex = "0.10.0"
+fancy-regex = "0.11.0"
 fuzzy-matcher = "0.3.7"
 is_executable = "1.0.1"
-once_cell = "1.16.0"
+once_cell = "1.17.0"
 log = "0.4"
-miette = { version = "5.1.0", features = ["fancy-no-backtrace"] }
+miette = { version = "5.5.0", features = ["fancy-no-backtrace"] }
 percent-encoding = "2"
-sysinfo = "0.26.2"
+sysinfo = "0.27.7"
 thiserror = "1.0.31"
 
 [features]

crates/nu-cli/src/completions/command_completions.rs

@@ -164,7 +164,7 @@ impl Completer for CommandCompletion {
             .flattened
             .iter()
             .rev()
-            .skip_while(|x| x.0.end > pos)
+            .skip_while(|x| x.0.end + offset > pos)
             .take_while(|x| {
                 matches!(
                     x.1,

crates/nu-cli/src/completions/completer.rs

@@ -104,18 +104,25 @@ impl NuCompleter {
                     return Some(result);
                 }
             }
-            Err(err) => println!("failed to eval completer block: {}", err),
+            Err(err) => println!("failed to eval completer block: {err}"),
         }
 
         None
     }
 
     fn completion_helper(&mut self, line: &str, pos: usize) -> Vec<Suggestion> {
+        // pos: is the position of the cursor in the shell input.
+        // e.g. lets say you have an alias -> `alias ll = ls -l` and you type in the shell:
+        // > ll -a | c
+        // and your cursor is right after `c` then `pos` = 9
+
         let mut working_set = StateWorkingSet::new(&self.engine_state);
-        let offset = working_set.next_span_start();
+        let mut offset = working_set.next_span_start();
         let (mut new_line, alias_offset) = try_find_alias(line.as_bytes(), &working_set);
-        let initial_line = line.to_string();
-        let alias_total_offset: usize = alias_offset.iter().sum();
+        // new_line: vector containing all alias "translations" so if it was `ll` now is `ls -l`.
+        // alias_offset:vector the offset between the name and the alias)
+        let initial_line = line.to_string(); // Entire line in the shell input.
+        let alias_total_offset: usize = alias_offset.iter().sum(); // the sum of all alias offsets.
         new_line.insert(alias_total_offset + pos, b'a');
         let pos = offset + pos;
         let config = self.engine_state.get_config();
@@ -128,7 +135,8 @@ impl NuCompleter {
                     PipelineElement::Expression(_, expr)
                     | PipelineElement::Redirection(_, _, expr)
                     | PipelineElement::And(_, expr)
-                    | PipelineElement::Or(_, expr) => {
+                    | PipelineElement::Or(_, expr)
+                    | PipelineElement::SeparateRedirection { out: (_, expr), .. } => {
                         let flattened: Vec<_> = flatten_expression(&working_set, &expr);
                         let span_offset: usize = alias_offset.iter().sum();
                         let mut spans: Vec<String> = vec![];
@@ -155,14 +163,22 @@ impl NuCompleter {
                                     most_left_variable(flat_idx, &working_set, flattened.clone());
 
                                 // Create a new span
-                                let new_span = if flat_idx == 0 {
-                                    Span::new(flat.0.start, flat.0.end - 1 - span_offset)
-                                } else {
-                                    Span::new(
-                                        flat.0.start - span_offset,
-                                        flat.0.end - 1 - span_offset,
-                                    )
-                                };
+                                // if flat_idx == 0
+                                let mut span_start = flat.0.start;
+                                let mut span_end = flat.0.end - 1 - span_offset;
+
+                                if flat_idx != 0 {
+                                    span_start = flat.0.start - span_offset;
+                                    span_end = flat.0.end - 1 - span_offset;
+                                }
+
+                                if span_end < span_start {
+                                    span_start = flat.0.start;
+                                    span_end = flat.0.end - 1;
+                                    offset += span_offset
+                                }
+
+                                let new_span = Span::new(span_start, span_end);
 
                                 // Parses the prefix. Completion should look up to the cursor position, not after.
                                 let mut prefix = working_set.get_span_contents(flat.0).to_vec();
@@ -177,6 +193,10 @@ impl NuCompleter {
                                         most_left_var.unwrap_or((vec![], vec![])),
                                     );
 
+                                    if offset > new_span.start {
+                                        offset -= span_offset;
+                                    }
+
                                     return self.process_completion(
                                         &mut completer,
                                         &working_set,

crates/nu-cli/src/completions/custom_completions.rs

@@ -66,6 +66,7 @@ impl Completer for CustomCompletion {
                 ],
                 redirect_stdout: true,
                 redirect_stderr: true,
+                parser_info: vec![],
             },
             PipelineData::empty(),
         );
@@ -73,8 +74,8 @@ impl Completer for CustomCompletion {
         let mut custom_completion_options = None;
 
         // Parse result
-        let suggestions = match result {
-            Ok(pd) => {
+        let suggestions = result
+            .map(|pd| {
                 let value = pd.into_value(span);
                 match &value {
                     Value::Record { .. } => {
@@ -131,9 +132,8 @@ impl Completer for CustomCompletion {
                     Value::List { vals, .. } => map_value_completions(vals.iter(), span, offset),
                     _ => vec![],
                 }
-            }
-            _ => vec![],
-        };
+            })
+            .unwrap_or_default();
 
         if let Some(custom_completion_options) = custom_completion_options {
             filter(&prefix, suggestions, &custom_completion_options)

crates/nu-cli/src/completions/directory_completions.rs

@@ -33,14 +33,7 @@ impl Completer for DirectoryCompletion {
         _: usize,
         options: &CompletionOptions,
     ) -> Vec<Suggestion> {
-        let cwd = if let Some(d) = self.engine_state.get_env_var("PWD") {
-            match d.as_string() {
-                Ok(s) => s,
-                Err(_) => "".to_string(),
-            }
-        } else {
-            "".to_string()
-        };
+        let cwd = self.engine_state.current_work_dir();
         let partial = String::from_utf8_lossy(&prefix).to_string();
 
         // Filter only the folders
@@ -126,7 +119,7 @@ pub fn directory_completion(
                             let mut file_name = entry.file_name().to_string_lossy().into_owned();
                             if matches(&partial, &file_name, options) {
                                 let mut path = if prepend_base_dir(original_input, &base_dir_name) {
-                                    format!("{}{}", base_dir_name, file_name)
+                                    format!("{base_dir_name}{file_name}")
                                 } else {
                                     file_name.to_string()
                                 };
@@ -142,7 +135,7 @@ pub fn directory_completion(
                                     || path.contains(' ')
                                     || path.contains('#')
                                 {
-                                    path = format!("`{}`", path);
+                                    path = format!("`{path}`");
                                 }
 
                                 Some((span, path))

crates/nu-cli/src/completions/dotnu_completions.rs

@@ -58,7 +58,7 @@ impl Completer for DotNuCompletion {
             };
 
         // Check if the base_dir is a folder
-        if base_dir != format!(".{}", SEP) {
+        if base_dir != format!(".{SEP}") {
             // Add the base dir into the directories to be searched
             search_dirs.push(base_dir.clone());
 
@@ -70,14 +70,7 @@ impl Completer for DotNuCompletion {
             partial = base_dir_partial;
         } else {
             // Fetch the current folder
-            let current_folder = if let Some(d) = self.engine_state.get_env_var("PWD") {
-                match d.as_string() {
-                    Ok(s) => s,
-                    Err(_) => "".to_string(),
-                }
-            } else {
-                "".to_string()
-            };
+            let current_folder = self.engine_state.current_work_dir();
             is_current_folder = true;
 
             // Add the current folder and the lib dirs into the

crates/nu-cli/src/completions/file_completions.rs

@@ -30,14 +30,7 @@ impl Completer for FileCompletion {
         _: usize,
         options: &CompletionOptions,
     ) -> Vec<Suggestion> {
-        let cwd = if let Some(d) = self.engine_state.get_env_var("PWD") {
-            match d.as_string() {
-                Ok(s) => s,
-                Err(_) => "".to_string(),
-            }
-        } else {
-            "".to_string()
-        };
+        let cwd = self.engine_state.current_work_dir();
         let prefix = String::from_utf8_lossy(&prefix).to_string();
         let output: Vec<_> = file_path_completion(span, &prefix, &cwd, options)
             .into_iter()
@@ -131,7 +124,7 @@ pub fn file_path_completion(
                     let mut file_name = entry.file_name().to_string_lossy().into_owned();
                     if matches(&partial, &file_name, options) {
                         let mut path = if prepend_base_dir(original_input, &base_dir_name) {
-                            format!("{}{}", base_dir_name, file_name)
+                            format!("{base_dir_name}{file_name}")
                         } else {
                             file_name.to_string()
                         };
@@ -146,8 +139,10 @@ pub fn file_path_completion(
                             || path.contains('"')
                             || path.contains(' ')
                             || path.contains('#')
+                            || path.contains('(')
+                            || path.contains(')')
                         {
-                            path = format!("`{}`", path);
+                            path = format!("`{path}`");
                         }
 
                         Some((span, path))
@@ -175,7 +170,7 @@ pub fn matches(partial: &str, from: &str, options: &CompletionOptions) -> bool {
 
 /// Returns whether the base_dir should be prepended to the file path
 pub fn prepend_base_dir(input: &str, base_dir: &str) -> bool {
-    if base_dir == format!(".{}", SEP) {
+    if base_dir == format!(".{SEP}") {
         // if the current base_dir path is the local folder we only add a "./" prefix if the user
         // input already includes a local folder prefix.
         let manually_entered = {

crates/nu-cli/src/completions/variable_completions.rs

@@ -9,6 +9,8 @@ use reedline::Suggestion;
 use std::str;
 use std::sync::Arc;
 
+use super::MatchAlgorithm;
+
 #[derive(Clone)]
 pub struct VariableCompletion {
     engine_state: Arc<EngineState>, // TODO: Is engine state necessary? It's already a part of working set in fetch()
@@ -73,10 +75,11 @@ impl Completer for VariableCompletion {
                         for suggestion in
                             nested_suggestions(val.clone(), nested_levels, current_span)
                         {
-                            if options
-                                .match_algorithm
-                                .matches_u8(suggestion.value.as_bytes(), &prefix)
-                            {
+                            if options.match_algorithm.matches_u8_insensitive(
+                                options.case_sensitive,
+                                suggestion.value.as_bytes(),
+                                &prefix,
+                            ) {
                                 output.push(suggestion);
                             }
                         }
@@ -86,10 +89,11 @@ impl Completer for VariableCompletion {
                 } else {
                     // No nesting provided, return all env vars
                     for env_var in env_vars {
-                        if options
-                            .match_algorithm
-                            .matches_u8(env_var.0.as_bytes(), &prefix)
-                        {
+                        if options.match_algorithm.matches_u8_insensitive(
+                            options.case_sensitive,
+                            env_var.0.as_bytes(),
+                            &prefix,
+                        ) {
                             output.push(Suggestion {
                                 value: env_var.0,
                                 description: None,
@@ -116,10 +120,11 @@ impl Completer for VariableCompletion {
                     for suggestion in
                         nested_suggestions(nuval, self.var_context.1.clone(), current_span)
                     {
-                        if options
-                            .match_algorithm
-                            .matches_u8(suggestion.value.as_bytes(), &prefix)
-                        {
+                        if options.match_algorithm.matches_u8_insensitive(
+                            options.case_sensitive,
+                            suggestion.value.as_bytes(),
+                            &prefix,
+                        ) {
                             output.push(suggestion);
                         }
                     }
@@ -138,10 +143,11 @@ impl Completer for VariableCompletion {
                     for suggestion in
                         nested_suggestions(value, self.var_context.1.clone(), current_span)
                     {
-                        if options
-                            .match_algorithm
-                            .matches_u8(suggestion.value.as_bytes(), &prefix)
-                        {
+                        if options.match_algorithm.matches_u8_insensitive(
+                            options.case_sensitive,
+                            suggestion.value.as_bytes(),
+                            &prefix,
+                        ) {
                             output.push(suggestion);
                         }
                     }
@@ -153,10 +159,11 @@ impl Completer for VariableCompletion {
 
         // Variable completion (e.g: $en<tab> to complete $env)
         for builtin in builtins {
-            if options
-                .match_algorithm
-                .matches_u8(builtin.as_bytes(), &prefix)
-            {
+            if options.match_algorithm.matches_u8_insensitive(
+                options.case_sensitive,
+                builtin.as_bytes(),
+                &prefix,
+            ) {
                 output.push(Suggestion {
                     value: builtin.to_string(),
                     description: None,
@@ -178,7 +185,11 @@ impl Completer for VariableCompletion {
                 .rev()
             {
                 for v in &overlay_frame.vars {
-                    if options.match_algorithm.matches_u8(v.0, &prefix) {
+                    if options.match_algorithm.matches_u8_insensitive(
+                        options.case_sensitive,
+                        v.0,
+                        &prefix,
+                    ) {
                         output.push(Suggestion {
                             value: String::from_utf8_lossy(v.0).to_string(),
                             description: None,
@@ -200,7 +211,11 @@ impl Completer for VariableCompletion {
             .rev()
         {
             for v in &overlay_frame.vars {
-                if options.match_algorithm.matches_u8(v.0, &prefix) {
+                if options.match_algorithm.matches_u8_insensitive(
+                    options.case_sensitive,
+                    v.0,
+                    &prefix,
+                ) {
                     output.push(Suggestion {
                         value: String::from_utf8_lossy(v.0).to_string(),
                         description: None,
@@ -247,6 +262,20 @@ fn nested_suggestions(
 
             output
         }
+        Value::LazyRecord { val, .. } => {
+            // Add all the columns as completion
+            for column_name in val.column_names() {
+                output.push(Suggestion {
+                    value: column_name.to_string(),
+                    description: None,
+                    extra: None,
+                    span: current_span,
+                    append_whitespace: false,
+                });
+            }
+
+            output
+        }
 
         _ => output,
     }
@@ -281,3 +310,13 @@ fn recursive_value(val: Value, sublevels: Vec<Vec<u8>>) -> Value {
 
     val
 }
+
+impl MatchAlgorithm {
+    pub fn matches_u8_insensitive(&self, sensitive: bool, haystack: &[u8], needle: &[u8]) -> bool {
+        if sensitive {
+            self.matches_u8(haystack, needle)
+        } else {
+            self.matches_u8(&haystack.to_ascii_lowercase(), &needle.to_ascii_lowercase())
+        }
+    }
+}

crates/nu-cli/src/config_files.rs

@@ -1,7 +1,5 @@
 use crate::util::{eval_source, report_error};
 #[cfg(feature = "plugin")]
-use log::info;
-#[cfg(feature = "plugin")]
 use nu_parser::ParseError;
 #[cfg(feature = "plugin")]
 use nu_path::canonicalize_with;
@@ -9,6 +7,8 @@ use nu_protocol::engine::{EngineState, Stack, StateWorkingSet};
 #[cfg(feature = "plugin")]
 use nu_protocol::Spanned;
 use nu_protocol::{HistoryFileFormat, PipelineData};
+#[cfg(feature = "plugin")]
+use nu_utils::utils::perf;
 use std::path::PathBuf;
 
 #[cfg(feature = "plugin")]
@@ -24,6 +24,8 @@ pub fn read_plugin_file(
     plugin_file: Option<Spanned<String>>,
     storage_path: &str,
 ) {
+    let start_time = std::time::Instant::now();
+    let mut plug_path = String::new();
     // Reading signatures from signature file
     // The plugin.nu file stores the parsed signature collected from each registered plugin
     add_plugin_file(engine_state, plugin_file, storage_path);
@@ -31,7 +33,7 @@ pub fn read_plugin_file(
     let plugin_path = engine_state.plugin_signatures.clone();
     if let Some(plugin_path) = plugin_path {
         let plugin_filename = plugin_path.to_string_lossy();
-
+        plug_path = plugin_filename.to_string();
         if let Ok(contents) = std::fs::read(&plugin_path) {
             eval_source(
                 engine_state,
@@ -43,7 +45,13 @@ pub fn read_plugin_file(
         }
     }
 
-    info!("read_plugin_file {}:{}:{}", file!(), line!(), column!());
+    perf(
+        &format!("read_plugin_file {}", &plug_path),
+        start_time,
+        file!(),
+        line!(),
+        column!(),
+    );
 }
 
 #[cfg(feature = "plugin")]
@@ -56,13 +64,12 @@ pub fn add_plugin_file(
         let working_set = StateWorkingSet::new(engine_state);
         let cwd = working_set.get_cwd();
 
-        match canonicalize_with(&plugin_file.item, cwd) {
-            Ok(path) => engine_state.plugin_signatures = Some(path),
-            Err(_) => {
+        if let Ok(path) = canonicalize_with(&plugin_file.item, cwd) {
+            engine_state.plugin_signatures = Some(path)
+        } else {
             let e = ParseError::FileNotFound(plugin_file.item, plugin_file.span);
             report_error(&working_set, &e);
         }
-        }
     } else if let Some(mut plugin_path) = nu_path::config_dir() {
         // Path to store plugins signatures
         plugin_path.push(storage_path);

crates/nu-cli/src/eval_file.rs

@@ -29,10 +29,7 @@ pub fn evaluate_file(
 
     let cwd = current_dir(engine_state, stack)?;
 
-    let file_path = {
-        match canonicalize_with(&path, &cwd) {
-            Ok(p) => p,
-            Err(e) => {
+    let file_path = canonicalize_with(&path, cwd).unwrap_or_else(|e| {
         let working_set = StateWorkingSet::new(engine_state);
         report_error(
             &working_set,
@@ -42,13 +39,9 @@ pub fn evaluate_file(
             ),
         );
         std::process::exit(1);
-            }
-        }
-    };
+    });
 
-    let file_path_str = match file_path.to_str() {
-        Some(s) => s,
-        None => {
+    let file_path_str = file_path.to_str().unwrap_or_else(|| {
         let working_set = StateWorkingSet::new(engine_state);
         report_error(
             &working_set,
@@ -61,12 +54,11 @@ pub fn evaluate_file(
             ),
         );
         std::process::exit(1);
-        }
-    };
+    });
 
-    let file = match std::fs::read(&file_path).into_diagnostic() {
-        Ok(p) => p,
-        Err(e) => {
+    let file = std::fs::read(&file_path)
+        .into_diagnostic()
+        .unwrap_or_else(|e| {
             let working_set = StateWorkingSet::new(engine_state);
             report_error(
                 &working_set,
@@ -80,13 +72,21 @@ pub fn evaluate_file(
                 ),
             );
             std::process::exit(1);
-        }
-    };
+        });
 
     engine_state.start_in_file(Some(file_path_str));
 
-    let mut parent = file_path.clone();
-    parent.pop();
+    let parent = file_path.parent().unwrap_or_else(|| {
+        let working_set = StateWorkingSet::new(engine_state);
+        report_error(
+            &working_set,
+            &ShellError::FileNotFoundCustom(
+                format!("The file path '{file_path_str}' does not have a parent"),
+                Span::unknown(),
+            ),
+        );
+        std::process::exit(1);
+    });
 
     stack.add_env_var(
         "FILE_PWD".to_string(),
@@ -121,7 +121,7 @@ pub fn evaluate_file(
     Ok(())
 }
 
-pub fn print_table_or_error(
+pub(crate) fn print_table_or_error(
     engine_state: &mut EngineState,
     stack: &mut Stack,
     mut pipeline_data: PipelineData,
@@ -137,14 +137,11 @@ pub fn print_table_or_error(
 
     if let PipelineData::Value(Value::Error { error }, ..) = &pipeline_data {
         let working_set = StateWorkingSet::new(engine_state);
-
         report_error(&working_set, error);
-
         std::process::exit(1);
     }
 
-    match engine_state.find_decl("table".as_bytes(), &[]) {
-        Some(decl_id) => {
+    if let Some(decl_id) = engine_state.find_decl("table".as_bytes(), &[]) {
         let command = engine_state.get_decl(decl_id);
         if command.get_block_id().is_some() {
             print_or_exit(pipeline_data, engine_state, config);
@@ -162,18 +159,14 @@ pub fn print_table_or_error(
                 }
                 Err(error) => {
                     let working_set = StateWorkingSet::new(engine_state);
-
                     report_error(&working_set, &error);
-
                     std::process::exit(1);
                 }
             }
         }
-        }
-        None => {
+    } else {
         print_or_exit(pipeline_data, engine_state, config);
     }
-    };
 
     // Make sure everything has finished
     if let Some(exit_code) = exit_code {
@@ -199,9 +192,7 @@ fn print_or_exit(pipeline_data: PipelineData, engine_state: &mut EngineState, co
             std::process::exit(1);
         }
 
-        let mut out = item.into_string("\n", config);
-        out.push('\n');
-
-        let _ = stdout_write_all_and_flush(out).map_err(|err| eprintln!("{}", err));
+        let out = item.into_string("\n", config) + "\n";
+        let _ = stdout_write_all_and_flush(out).map_err(|err| eprintln!("{err}"));
     }
 }

crates/nu-cli/src/menus/description_menu.rs

@@ -411,10 +411,10 @@ impl DescriptionMenu {
                             RESET
                         )
                     } else {
-                        format!("  {}\r\n", example)
+                        format!("  {example}\r\n")
                     }
                 } else {
-                    format!("  {}\r\n", example)
+                    format!("  {example}\r\n")
                 }
             })
             .collect();
@@ -429,7 +429,7 @@ impl DescriptionMenu {
                 examples,
             )
         } else {
-            format!("\r\n\r\nExamples:\r\n{}", examples,)
+            format!("\r\n\r\nExamples:\r\n{examples}",)
         }
     }
 }

crates/nu-cli/src/menus/menu_completions.rs

@@ -81,13 +81,10 @@ fn convert_to_suggestions(
 ) -> Vec<Suggestion> {
     match value {
         Value::Record { .. } => {
-            let text = match value
+            let text = value
                 .get_data_by_key("value")
                 .and_then(|val| val.as_string().ok())
-            {
-                Some(val) => val,
-                None => "No value key".to_string(),
-            };
+                .unwrap_or_else(|| "No value key".to_string());
 
             let description = value
                 .get_data_by_key("description")
@@ -157,7 +154,7 @@ fn convert_to_suggestions(
             .flat_map(|val| convert_to_suggestions(val, line, pos, only_buffer_difference))
             .collect(),
         _ => vec![Suggestion {
-            value: format!("Not a record: {:?}", value),
+            value: format!("Not a record: {value:?}"),
             description: None,
             extra: None,
             span: reedline::Span {

crates/nu-cli/src/nu_highlight.rs

@@ -1,6 +1,6 @@
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{Category, Example, PipelineData, ShellError, Signature, Value};
+use nu_protocol::{Category, Example, PipelineData, ShellError, Signature, Type, Value};
 use reedline::Highlighter;
 
 #[derive(Clone)]
@@ -12,7 +12,9 @@ impl Command for NuHighlight {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("nu-highlight").category(Category::Strings)
+        Signature::build("nu-highlight")
+            .category(Category::Strings)
+            .input_output_types(vec![(Type::String, Type::String)])
     }
 
     fn usage(&self) -> &str {
@@ -33,7 +35,7 @@ impl Command for NuHighlight {
         let head = call.head;
 
         let ctrlc = engine_state.ctrlc.clone();
-        let engine_state = engine_state.clone();
+        let engine_state = std::sync::Arc::new(engine_state.clone());
         let config = engine_state.get_config().clone();
 
         let highlighter = crate::NuHighlighter {

crates/nu-cli/src/print.rs

@@ -2,7 +2,8 @@ use nu_engine::CallExt;
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
 use nu_protocol::{
-    Category, Example, IntoPipelineData, PipelineData, ShellError, Signature, SyntaxShape, Value,
+    Category, Example, IntoPipelineData, PipelineData, ShellError, Signature, SyntaxShape, Type,
+    Value,
 };
 
 #[derive(Clone)]
@@ -15,6 +16,7 @@ impl Command for Print {
 
     fn signature(&self) -> Signature {
         Signature::build("print")
+            .input_output_types(vec![(Type::Nothing, Type::Nothing)])
             .rest("rest", SyntaxShape::Any, "the values to print")
             .switch(
                 "no-newline",

crates/nu-cli/src/prompt.rs

@@ -91,7 +91,7 @@ impl NushellPrompt {
     }
 
     fn default_wrapped_custom_string(&self, str: String) -> String {
-        format!("({})", str)
+        format!("({str})")
     }
 }
 
@@ -105,7 +105,7 @@ impl Prompt for NushellPrompt {
         if let Some(prompt_string) = &self.left_prompt_string {
             prompt_string.replace('\n', "\r\n").into()
         } else {
-            let default = DefaultPrompt::new();
+            let default = DefaultPrompt::default();
             default
                 .render_prompt_left()
                 .to_string()
@@ -118,7 +118,7 @@ impl Prompt for NushellPrompt {
         if let Some(prompt_string) = &self.right_prompt_string {
             prompt_string.replace('\n', "\r\n").into()
         } else {
-            let default = DefaultPrompt::new();
+            let default = DefaultPrompt::default();
             default
                 .render_prompt_right()
                 .to_string()
@@ -130,32 +130,36 @@ impl Prompt for NushellPrompt {
     fn render_prompt_indicator(&self, edit_mode: PromptEditMode) -> Cow<str> {
         match edit_mode {
             PromptEditMode::Default => match &self.default_prompt_indicator {
-                Some(indicator) => indicator.as_str().into(),
-                None => "〉".into(),
-            },
+                Some(indicator) => indicator,
+                None => "〉",
+            }
+            .into(),
             PromptEditMode::Emacs => match &self.default_prompt_indicator {
-                Some(indicator) => indicator.as_str().into(),
-                None => "〉".into(),
-            },
+                Some(indicator) => indicator,
+                None => "〉",
+            }
+            .into(),
             PromptEditMode::Vi(vi_mode) => match vi_mode {
                 PromptViMode::Normal => match &self.default_vi_normal_prompt_indicator {
-                    Some(indicator) => indicator.as_str().into(),
-                    None => ": ".into(),
+                    Some(indicator) => indicator,
+                    None => ": ",
                 },
                 PromptViMode::Insert => match &self.default_vi_insert_prompt_indicator {
-                    Some(indicator) => indicator.as_str().into(),
-                    None => "〉".into(),
-                },
+                    Some(indicator) => indicator,
+                    None => "〉",
                 },
+            }
+            .into(),
             PromptEditMode::Custom(str) => self.default_wrapped_custom_string(str).into(),
         }
     }
 
     fn render_prompt_multiline_indicator(&self) -> Cow<str> {
         match &self.default_multiline_indicator {
-            Some(indicator) => indicator.as_str().into(),
-            None => "::: ".into(),
+            Some(indicator) => indicator,
+            None => "::: ",
         }
+        .into()
     }
 
     fn render_prompt_history_search_indicator(

crates/nu-cli/src/prompt_update.rs

@@ -1,6 +1,6 @@
 use crate::util::report_error;
 use crate::NushellPrompt;
-use log::info;
+use log::trace;
 use nu_engine::eval_subexpression;
 use nu_protocol::{
     engine::{EngineState, Stack, StateWorkingSet},
@@ -39,41 +39,37 @@ fn get_prompt_string(
                 // Use eval_subexpression to force a redirection of output, so we can use everything in prompt
                 let ret_val =
                     eval_subexpression(engine_state, &mut stack, block, PipelineData::empty());
-                info!(
+                trace!(
                     "get_prompt_string (block) {}:{}:{}",
                     file!(),
                     line!(),
                     column!()
                 );
 
-                match ret_val {
-                    Ok(ret_val) => Some(ret_val),
-                    Err(err) => {
+                ret_val
+                    .map_err(|err| {
                         let working_set = StateWorkingSet::new(engine_state);
                         report_error(&working_set, &err);
-                        None
-                    }
-                }
+                    })
+                    .ok()
             }
             Value::Block { val: block_id, .. } => {
                 let block = engine_state.get_block(block_id);
                 // Use eval_subexpression to force a redirection of output, so we can use everything in prompt
                 let ret_val = eval_subexpression(engine_state, stack, block, PipelineData::empty());
-                info!(
+                trace!(
                     "get_prompt_string (block) {}:{}:{}",
                     file!(),
                     line!(),
                     column!()
                 );
 
-                match ret_val {
-                    Ok(ret_val) => Some(ret_val),
-                    Err(err) => {
+                ret_val
+                    .map_err(|err| {
                         let working_set = StateWorkingSet::new(engine_state);
                         report_error(&working_set, &err);
-                        None
-                    }
-                }
+                    })
+                    .ok()
             }
             Value::String { .. } => Some(PipelineData::Value(v.clone(), None)),
             _ => None,
@@ -81,8 +77,7 @@ fn get_prompt_string(
         .and_then(|pipeline_data| {
             let output = pipeline_data.collect_string("", config).ok();
 
-            match output {
-                Some(mut x) => {
+            output.map(|mut x| {
                 // Just remove the very last newline.
                 if x.ends_with('\n') {
                     x.pop();
@@ -91,10 +86,8 @@ fn get_prompt_string(
                 if x.ends_with('\r') {
                     x.pop();
                 }
-                    Some(x)
-                }
-                None => None,
-            }
+                x
+            })
         })
 }
 
@@ -111,12 +104,12 @@ pub(crate) fn update_prompt<'prompt>(
     // Now that we have the prompt string lets ansify it.
     // <133 A><prompt><133 B><command><133 C><command output>
     let left_prompt_string = if config.shell_integration {
-        match left_prompt_string {
-            Some(prompt_string) => Some(format!(
-                "{}{}{}",
-                PRE_PROMPT_MARKER, prompt_string, POST_PROMPT_MARKER
-            )),
-            None => left_prompt_string,
+        if let Some(prompt_string) = left_prompt_string {
+            Some(format!(
+                "{PRE_PROMPT_MARKER}{prompt_string}{POST_PROMPT_MARKER}"
+            ))
+        } else {
+            left_prompt_string
         }
     } else {
         left_prompt_string
@@ -148,7 +141,7 @@ pub(crate) fn update_prompt<'prompt>(
     );
 
     let ret_val = nu_prompt as &dyn Prompt;
-    info!("update_prompt {}:{}:{}", file!(), line!(), column!());
+    trace!("update_prompt {}:{}:{}", file!(), line!(), column!());
 
     ret_val
 }

crates/nu-cli/src/reedline_config.rs

@@ -7,8 +7,7 @@ use nu_parser::parse;
 use nu_protocol::{
     create_menus,
     engine::{EngineState, Stack, StateWorkingSet},
-    extract_value, Config, IntoPipelineData, ParsedKeybinding, ParsedMenu, PipelineData,
-    ShellError, Span, Value,
+    extract_value, Config, ParsedKeybinding, ParsedMenu, PipelineData, ShellError, Span, Value,
 };
 use reedline::{
     default_emacs_keybindings, default_vi_insert_keybindings, default_vi_normal_keybindings,
@@ -110,7 +109,7 @@ pub(crate) fn add_menus(
             };
 
             let mut temp_stack = Stack::new();
-            let input = Value::nothing(Span::test_data()).into_pipeline_data();
+            let input = PipelineData::Empty;
             let res = eval_block(&engine_state, &mut temp_stack, &block, input, false, false)?;
 
             if let PipelineData::Value(value, None) = res {
@@ -652,14 +651,15 @@ fn add_parsed_keybinding(
             let pos1 = char_iter.next();
             let pos2 = char_iter.next();
 
-            let char = match (pos1, pos2) {
-                (Some(char), None) => Ok(char),
-                _ => Err(ShellError::UnsupportedConfigValue(
+            let char = if let (Some(char), None) = (pos1, pos2) {
+                char
+            } else {
+                return Err(ShellError::UnsupportedConfigValue(
                     "char_<CHAR: unicode codepoint>".to_string(),
                     c.to_string(),
                     keybinding.keycode.span()?,
-                )),
-            }?;
+                ));
+            };
 
             KeyCode::Char(char)
         }
@@ -680,10 +680,10 @@ fn add_parsed_keybinding(
             let fn_num: u8 = c[1..]
                 .parse()
                 .ok()
-                .filter(|num| matches!(num, 1..=12))
+                .filter(|num| matches!(num, 1..=20))
                 .ok_or(ShellError::UnsupportedConfigValue(
-                    "(f1|f2|...|f12)".to_string(),
-                    format!("unknown function key: {}", c),
+                    "(f1|f2|...|f20)".to_string(),
+                    format!("unknown function key: {c}"),
                     keybinding.keycode.span()?,
                 ))?;
             KeyCode::F(fn_num)
@@ -990,7 +990,7 @@ mod test {
     #[test]
     fn test_send_event() {
         let cols = vec!["send".to_string()];
-        let vals = vec![Value::string("Enter", Span::test_data())];
+        let vals = vec![Value::test_string("Enter")];
 
         let span = Span::test_data();
         let b = EventType::try_from_columns(&cols, &vals, &span).unwrap();
@@ -1010,7 +1010,7 @@ mod test {
     #[test]
     fn test_edit_event() {
         let cols = vec!["edit".to_string()];
-        let vals = vec![Value::string("Clear", Span::test_data())];
+        let vals = vec![Value::test_string("Clear")];
 
         let span = Span::test_data();
         let b = EventType::try_from_columns(&cols, &vals, &span).unwrap();
@@ -1034,8 +1034,8 @@ mod test {
     fn test_send_menu() {
         let cols = vec!["send".to_string(), "name".to_string()];
         let vals = vec![
-            Value::string("Menu", Span::test_data()),
-            Value::string("history_menu", Span::test_data()),
+            Value::test_string("Menu"),
+            Value::test_string("history_menu"),
         ];
 
         let span = Span::test_data();
@@ -1061,8 +1061,8 @@ mod test {
         // Menu event
         let cols = vec!["send".to_string(), "name".to_string()];
         let vals = vec![
-            Value::string("Menu", Span::test_data()),
-            Value::string("history_menu", Span::test_data()),
+            Value::test_string("Menu"),
+            Value::test_string("history_menu"),
         ];
 
         let menu_event = Value::Record {
@@ -1073,7 +1073,7 @@ mod test {
 
         // Enter event
         let cols = vec!["send".to_string()];
-        let vals = vec![Value::string("Enter", Span::test_data())];
+        let vals = vec![Value::test_string("Enter")];
 
         let enter_event = Value::Record {
             cols,
@@ -1114,8 +1114,8 @@ mod test {
         // Menu event
         let cols = vec!["send".to_string(), "name".to_string()];
         let vals = vec![
-            Value::string("Menu", Span::test_data()),
-            Value::string("history_menu", Span::test_data()),
+            Value::test_string("Menu"),
+            Value::test_string("history_menu"),
         ];
 
         let menu_event = Value::Record {
@@ -1126,7 +1126,7 @@ mod test {
 
         // Enter event
         let cols = vec!["send".to_string()];
-        let vals = vec![Value::string("Enter", Span::test_data())];
+        let vals = vec![Value::test_string("Enter")];
 
         let enter_event = Value::Record {
             cols,
@@ -1154,7 +1154,7 @@ mod test {
     #[test]
     fn test_error() {
         let cols = vec!["not_exist".to_string()];
-        let vals = vec![Value::string("Enter", Span::test_data())];
+        let vals = vec![Value::test_string("Enter")];
 
         let span = Span::test_data();
         let b = EventType::try_from_columns(&cols, &vals, &span);

crates/nu-cli/src/repl.rs

@@ -5,18 +5,21 @@ use crate::{
     util::{eval_source, get_guaranteed_cwd, report_error, report_error_new},
     NuHighlighter, NuValidator, NushellPrompt,
 };
-use log::{info, trace, warn};
+use crossterm::cursor::CursorShape;
+use log::{trace, warn};
 use miette::{IntoDiagnostic, Result};
 use nu_color_config::StyleComputer;
 use nu_engine::{convert_env_values, eval_block, eval_block_with_early_return};
 use nu_parser::{lex, parse, trim_quotes_str};
 use nu_protocol::{
     ast::PathMember,
+    config::NuCursorShape,
     engine::{EngineState, ReplOperation, Stack, StateWorkingSet},
     format_duration, BlockId, HistoryFileFormat, PipelineData, PositionalArg, ShellError, Span,
     Spanned, Type, Value, VarId,
 };
-use reedline::{DefaultHinter, EditCommand, Emacs, SqliteBackedHistory, Vi};
+use nu_utils::utils::perf;
+use reedline::{CursorConfig, DefaultHinter, EditCommand, Emacs, SqliteBackedHistory, Vi};
 use std::{
     io::{self, Write},
     sync::atomic::Ordering,
@@ -39,6 +42,7 @@ pub fn evaluate_repl(
     stack: &mut Stack,
     nushell_path: &str,
     prerun_command: Option<Spanned<String>>,
+    entire_start_time: Instant,
 ) -> Result<()> {
     use reedline::{FileBackedHistory, Reedline, Signal};
 
@@ -56,18 +60,19 @@ pub fn evaluate_repl(
 
     let mut nu_prompt = NushellPrompt::new();
 
-    info!(
-        "translate environment vars {}:{}:{}",
-        file!(),
-        line!(),
-        column!()
-    );
-
+    let start_time = std::time::Instant::now();
     // Translate environment variables from Strings to Values
     if let Some(e) = convert_env_values(engine_state, stack) {
         let working_set = StateWorkingSet::new(engine_state);
         report_error(&working_set, &e);
     }
+    perf(
+        "translate env vars",
+        start_time,
+        file!(),
+        line!(),
+        column!(),
+    );
 
     // seed env vars
     stack.add_env_var(
@@ -77,33 +82,25 @@ pub fn evaluate_repl(
 
     stack.add_env_var("LAST_EXIT_CODE".into(), Value::int(0, Span::unknown()));
 
-    info!(
-        "load config initially {}:{}:{}",
-        file!(),
-        line!(),
-        column!()
-    );
-
-    info!("setup reedline {}:{}:{}", file!(), line!(), column!());
-
+    let mut start_time = std::time::Instant::now();
     let mut line_editor = Reedline::create();
 
     // Now that reedline is created, get the history session id and store it in engine_state
-    let hist_sesh = match line_editor.get_history_session_id() {
-        Some(id) => i64::from(id),
-        None => 0,
-    };
+    let hist_sesh = line_editor
+        .get_history_session_id()
+        .map(i64::from)
+        .unwrap_or(0);
     engine_state.history_session_id = hist_sesh;
+    perf("setup reedline", start_time, file!(), line!(), column!());
 
     let config = engine_state.get_config();
 
+    start_time = std::time::Instant::now();
     let history_path = crate::config_files::get_history_path(
         nushell_path,
         engine_state.config.history_file_format,
     );
     if let Some(history_path) = history_path.as_deref() {
-        info!("setup history {}:{}:{}", file!(), line!(), column!());
-
         let history: Box<dyn reedline::History> = match engine_state.config.history_file_format {
             HistoryFileFormat::PlainText => Box::new(
                 FileBackedHistory::with_file(
@@ -118,7 +115,9 @@ pub fn evaluate_repl(
         };
         line_editor = line_editor.with_history(history);
     };
+    perf("setup history", start_time, file!(), line!(), column!());
 
+    start_time = std::time::Instant::now();
     let sys = sysinfo::System::new();
 
     let show_banner = config.show_banner;
@@ -126,61 +125,89 @@ pub fn evaluate_repl(
     if show_banner {
         let banner = get_banner(engine_state, stack);
         if use_ansi {
-            println!("{}", banner);
+            println!("{banner}");
         } else {
             println!("{}", nu_utils::strip_ansi_string_likely(banner));
         }
     }
+    perf(
+        "get sysinfo/show banner",
+        start_time,
+        file!(),
+        line!(),
+        column!(),
+    );
 
     if let Some(s) = prerun_command {
         eval_source(
             engine_state,
             stack,
             s.item.as_bytes(),
-            &format!("entry #{}", entry_num),
+            &format!("entry #{entry_num}"),
             PipelineData::empty(),
         );
         engine_state.merge_env(stack, get_guaranteed_cwd(engine_state, stack))?;
     }
 
     loop {
-        info!(
-            "load config each loop {}:{}:{}",
-            file!(),
-            line!(),
-            column!()
-        );
+        let loop_start_time = std::time::Instant::now();
 
         let cwd = get_guaranteed_cwd(engine_state, stack);
 
+        start_time = std::time::Instant::now();
         // Before doing anything, merge the environment from the previous REPL iteration into the
         // permanent state.
         if let Err(err) = engine_state.merge_env(stack, cwd) {
             report_error_new(engine_state, &err);
         }
+        perf("merge env", start_time, file!(), line!(), column!());
 
+        start_time = std::time::Instant::now();
         //Reset the ctrl-c handler
         if let Some(ctrlc) = &mut engine_state.ctrlc {
             ctrlc.store(false, Ordering::SeqCst);
         }
+        perf("reset ctrlc", start_time, file!(), line!(), column!());
+
+        start_time = std::time::Instant::now();
         // Reset the SIGQUIT handler
         if let Some(sig_quit) = engine_state.get_sig_quit() {
             sig_quit.store(false, Ordering::SeqCst);
         }
+        perf("reset sig_quit", start_time, file!(), line!(), column!());
 
+        start_time = std::time::Instant::now();
         let config = engine_state.get_config();
 
-        info!("setup colors {}:{}:{}", file!(), line!(), column!());
-
-        info!("update reedline {}:{}:{}", file!(), line!(), column!());
         let engine_reference = std::sync::Arc::new(engine_state.clone());
+
+        // Find the configured cursor shapes for each mode
+        let cursor_config = CursorConfig {
+            vi_insert: Some(map_nucursorshape_to_cursorshape(
+                config.cursor_shape_vi_insert,
+            )),
+            vi_normal: Some(map_nucursorshape_to_cursorshape(
+                config.cursor_shape_vi_normal,
+            )),
+            emacs: Some(map_nucursorshape_to_cursorshape(config.cursor_shape_emacs)),
+        };
+        perf(
+            "get config/cursor config",
+            start_time,
+            file!(),
+            line!(),
+            column!(),
+        );
+
+        start_time = std::time::Instant::now();
+
         line_editor = line_editor
             .with_highlighter(Box::new(NuHighlighter {
-                engine_state: engine_state.clone(),
+                engine_state: engine_reference.clone(),
                 config: config.clone(),
             }))
             .with_validator(Box::new(NuValidator {
-                engine_state: engine_state.clone(),
+                engine_state: engine_reference.clone(),
             }))
             .with_completer(Box::new(NuCompleter::new(
                 engine_reference.clone(),
@@ -188,10 +215,13 @@ pub fn evaluate_repl(
             )))
             .with_quick_completions(config.quick_completions)
             .with_partial_completions(config.partial_completions)
-            .with_ansi_colors(config.use_ansi_coloring);
+            .with_ansi_colors(config.use_ansi_coloring)
+            .with_cursor_config(cursor_config);
+        perf("reedline builder", start_time, file!(), line!(), column!());
 
         let style_computer = StyleComputer::from_config(engine_state, stack);
 
+        start_time = std::time::Instant::now();
         line_editor = if config.use_ansi_coloring {
             line_editor.with_hinter(Box::new({
                 // As of Nov 2022, "hints" color_config closures only get `null` passed in.
@@ -201,16 +231,23 @@ pub fn evaluate_repl(
         } else {
             line_editor.disable_hints()
         };
+        perf(
+            "reedline coloring/style_computer",
+            start_time,
+            file!(),
+            line!(),
+            column!(),
+        );
 
-        line_editor = match add_menus(line_editor, engine_reference, stack, config) {
-            Ok(line_editor) => line_editor,
-            Err(e) => {
+        start_time = std::time::Instant::now();
+        line_editor = add_menus(line_editor, engine_reference, stack, config).unwrap_or_else(|e| {
             let working_set = StateWorkingSet::new(engine_state);
             report_error(&working_set, &e);
             Reedline::create()
-            }
-        };
+        });
+        perf("reedline menus", start_time, file!(), line!(), column!());
 
+        start_time = std::time::Instant::now();
         let buffer_editor = if !config.buffer_editor.is_empty() {
             Some(config.buffer_editor.clone())
         } else {
@@ -231,17 +268,23 @@ pub fn evaluate_repl(
         } else {
             line_editor
         };
+        perf(
+            "reedline buffer_editor",
+            start_time,
+            file!(),
+            line!(),
+            column!(),
+        );
 
+        start_time = std::time::Instant::now();
         if config.sync_history_on_enter {
-            info!("sync history {}:{}:{}", file!(), line!(), column!());
-
             if let Err(e) = line_editor.sync_history() {
                 warn!("Failed to sync history: {}", e);
             }
         }
+        perf("sync_history", start_time, file!(), line!(), column!());
 
-        info!("setup keybindings {}:{}:{}", file!(), line!(), column!());
-
+        start_time = std::time::Instant::now();
         // Changing the line editor based on the found keybindings
         line_editor = match create_keybindings(config) {
             Ok(keybindings) => match keybindings {
@@ -263,9 +306,9 @@ pub fn evaluate_repl(
                 line_editor
             }
         };
+        perf("keybindings", start_time, file!(), line!(), column!());
 
-        info!("prompt_update {}:{}:{}", file!(), line!(), column!());
-
+        start_time = std::time::Instant::now();
         // Right before we start our prompt and take input from the user,
         // fire the "pre_prompt" hook
         if let Some(hook) = config.hooks.pre_prompt.clone() {
@@ -273,7 +316,9 @@ pub fn evaluate_repl(
                 report_error_new(engine_state, &err);
             }
         }
+        perf("pre-prompt hook", start_time, file!(), line!(), column!());
 
+        start_time = std::time::Instant::now();
         // Next, check all the environment variables they ask for
         // fire the "env_change" hook
         let config = engine_state.get_config();
@@ -282,19 +327,23 @@ pub fn evaluate_repl(
         {
             report_error_new(engine_state, &error)
         }
+        perf("env-change hook", start_time, file!(), line!(), column!());
 
+        start_time = std::time::Instant::now();
         let config = engine_state.get_config();
         let prompt = prompt_update::update_prompt(config, engine_state, stack, &mut nu_prompt);
+        perf("update_prompt", start_time, file!(), line!(), column!());
 
         entry_num += 1;
 
-        info!(
-            "finished setup, starting repl {}:{}:{}",
-            file!(),
-            line!(),
-            column!()
+        if entry_num == 1 && show_banner {
+            println!(
+                "Startup Time: {}",
+                format_duration(entire_start_time.elapsed().as_nanos() as i64)
             );
+        }
 
+        start_time = std::time::Instant::now();
         let input = line_editor.read_line(prompt);
         let shell_integration = config.shell_integration;
 
@@ -421,7 +470,7 @@ pub fn evaluate_repl(
                         engine_state,
                         stack,
                         s.as_bytes(),
-                        &format!("entry #{}", entry_num),
+                        &format!("entry #{entry_num}"),
                         PipelineData::empty(),
                     );
                 }
@@ -479,7 +528,7 @@ pub fn evaluate_repl(
                         // ESC]0;stringBEL -- Set icon name and window title to string
                         // ESC]1;stringBEL -- Set icon name to string
                         // ESC]2;stringBEL -- Set window title to string
-                        run_ansi_sequence(&format!("\x1b]2;{}\x07", maybe_abbrev_path))?;
+                        run_ansi_sequence(&format!("\x1b]2;{maybe_abbrev_path}\x07"))?;
                     }
                     run_ansi_sequence(RESET_APPLICATION_MODE)?;
                 }
@@ -519,7 +568,7 @@ pub fn evaluate_repl(
             Err(err) => {
                 let message = err.to_string();
                 if !message.contains("duration") {
-                    eprintln!("Error: {:?}", err);
+                    eprintln!("Error: {err:?}");
                     // TODO: Identify possible error cases where a hard failure is preferable
                     // Ignoring and reporting could hide bigger problems
                     // e.g. https://github.com/nushell/nushell/issues/6452
@@ -530,11 +579,34 @@ pub fn evaluate_repl(
                 }
             }
         }
+        perf(
+            "processing line editor input",
+            start_time,
+            file!(),
+            line!(),
+            column!(),
+        );
+
+        perf(
+            "finished repl loop",
+            loop_start_time,
+            file!(),
+            line!(),
+            column!(),
+        );
     }
 
     Ok(())
 }
 
+fn map_nucursorshape_to_cursorshape(shape: NuCursorShape) -> CursorShape {
+    match shape {
+        NuCursorShape::Block => CursorShape::Block,
+        NuCursorShape::UnderScore => CursorShape::UnderScore,
+        NuCursorShape::Line => CursorShape::Line,
+    }
+}
+
 fn get_banner(engine_state: &mut EngineState, stack: &mut Stack) -> String {
     let age = match eval_string_with_input(
         engine_state,
@@ -558,15 +630,7 @@ Our {}Documentation{} is located at {}http://nushell.sh{}
 {}Tweet{} us at {}@nu_shell{}
 
 It's been this long since {}Nushell{}'s first commit:
-{}
-
-{}You can disable this banner using the {}config nu{}{} command
-to modify the config.nu file and setting show_banner to false.
-
-let-env config = {{
-    show_banner: false
-    ...
-}}{}
+{}{}
 "#,
         "\x1b[32m",   //start line 1 green
         "\x1b[32m",   //start line 2
@@ -598,10 +662,6 @@ let-env config = {{
         "\x1b[32m",   //before Nushell
         "\x1b[0m",    //after Nushell
         age,
-        "\x1b[2;37m", //before banner disable dim white
-        "\x1b[2;36m", //before config nu dim cyan
-        "\x1b[0m",    //after config nu
-        "\x1b[2;37m", //after config nu dim white
         "\x1b[0m", //after banner disable
     );
 
@@ -639,7 +699,7 @@ pub fn eval_string_with_input(
         false,
         true,
     )
-    .map(|x| x.into_value(Span::test_data()))
+    .map(|x| x.into_value(Span::unknown()))
 }
 
 pub fn get_command_finished_marker(stack: &Stack, engine_state: &EngineState) -> String {
@@ -734,8 +794,11 @@ pub fn eval_hook(
             }
         }
         Value::Record { .. } => {
-            let do_run_hook =
-                if let Ok(condition) = value.clone().follow_cell_path(&[condition_path], false) {
+            let do_run_hook = if let Ok(condition) =
+                value
+                    .clone()
+                    .follow_cell_path(&[condition_path], false, false)
+            {
                 match condition {
                     Value::Block {
                         val: block_id,
@@ -787,7 +850,7 @@ pub fn eval_hook(
             };
 
             if do_run_hook {
-                match value.clone().follow_cell_path(&[code_path], false)? {
+                match value.clone().follow_cell_path(&[code_path], false, false)? {
                     Value::String {
                         val,
                         span: source_span,
@@ -957,9 +1020,9 @@ fn run_hook_block(
         }
     }
 
-    match eval_block_with_early_return(engine_state, &mut callee_stack, block, input, false, false)
-    {
-        Ok(pipeline_data) => {
+    let pipeline_data =
+        eval_block_with_early_return(engine_state, &mut callee_stack, block, input, false, false)?;
+
     if let PipelineData::Value(Value::Error { error }, _) = pipeline_data {
         return Err(error);
     }
@@ -981,23 +1044,17 @@ fn run_hook_block(
     }
     Ok(pipeline_data)
 }
-        Err(err) => Err(err),
-    }
-}
 
 fn run_ansi_sequence(seq: &str) -> Result<(), ShellError> {
-    match io::stdout().write_all(seq.as_bytes()) {
-        Ok(it) => it,
-        Err(err) => {
-            return Err(ShellError::GenericError(
+    io::stdout().write_all(seq.as_bytes()).map_err(|e| {
+        ShellError::GenericError(
             "Error writing ansi sequence".into(),
-                err.to_string(),
+            e.to_string(),
             Some(Span::unknown()),
             None,
             Vec::new(),
-            ));
-        }
-    };
+        )
+    })?;
     io::stdout().flush().map_err(|e| {
         ShellError::GenericError(
             "Error flushing stdio".into(),

crates/nu-cli/src/syntax_highlight.rs

@@ -6,9 +6,10 @@ use nu_protocol::ast::{Argument, Block, Expr, Expression, PipelineElement};
 use nu_protocol::engine::{EngineState, StateWorkingSet};
 use nu_protocol::{Config, Span};
 use reedline::{Highlighter, StyledText};
+use std::sync::Arc;
 
 pub struct NuHighlighter {
-    pub engine_state: EngineState,
+    pub engine_state: Arc<EngineState>,
     pub config: Config,
 }
 
@@ -233,7 +234,8 @@ fn find_matching_block_end_in_block(
                 PipelineElement::Expression(_, e)
                 | PipelineElement::Redirection(_, _, e)
                 | PipelineElement::And(_, e)
-                | PipelineElement::Or(_, e) => {
+                | PipelineElement::Or(_, e)
+                | PipelineElement::SeparateRedirection { out: (_, e), .. } => {
                     if e.span.contains(global_cursor_offset) {
                         if let Some(pos) = find_matching_block_end_in_expr(
                             line,
@@ -352,6 +354,7 @@ fn find_matching_block_end_in_expr(
                     let opt_expr = match arg {
                         Argument::Named((_, _, opt_expr)) => opt_expr.as_ref(),
                         Argument::Positional(inner_expr) => Some(inner_expr),
+                        Argument::Unknown(inner_expr) => Some(inner_expr),
                     };
 
                     if let Some(inner_expr) = opt_expr {

crates/nu-cli/src/util.rs

@@ -9,6 +9,7 @@ use nu_protocol::{
 };
 #[cfg(windows)]
 use nu_utils::enable_vt_processing;
+use nu_utils::utils::perf;
 use std::path::{Path, PathBuf};
 
 // This will collect environment variables from std::env and adds them to a stack.
@@ -43,7 +44,7 @@ fn gather_env_vars(
         report_error(
             &working_set,
             &ShellError::GenericError(
-                format!("Environment variable was not captured: {}", env_str),
+                format!("Environment variable was not captured: {env_str}"),
                 "".to_string(),
                 None,
                 Some(msg.into()),
@@ -79,8 +80,7 @@ fn gather_env_vars(
                     "".to_string(),
                     None,
                     Some(format!(
-                        "Retrieving current directory failed: {:?} not a valid utf-8 path",
-                        init_cwd
+                        "Retrieving current directory failed: {init_cwd:?} not a valid utf-8 path"
                     )),
                     Vec::new(),
                 ),
@@ -204,6 +204,8 @@ pub fn eval_source(
     fname: &str,
     input: PipelineData,
 ) -> bool {
+    let start_time = std::time::Instant::now();
+
     let (block, delta) = {
         let mut working_set = StateWorkingSet::new(engine_state);
         let (output, err) = parse(
@@ -282,6 +284,13 @@ pub fn eval_source(
             return false;
         }
     }
+    perf(
+        &format!("eval_source {}", &fname),
+        start_time,
+        file!(),
+        line!(),
+        column!(),
+    );
 
     true
 }
@@ -315,27 +324,19 @@ pub fn report_error_new(
 }
 
 pub fn get_init_cwd() -> PathBuf {
-    match std::env::current_dir() {
-        Ok(cwd) => cwd,
-        Err(_) => match std::env::var("PWD") {
-            Ok(cwd) => PathBuf::from(cwd),
-            Err(_) => match nu_path::home_dir() {
-                Some(cwd) => cwd,
-                None => PathBuf::new(),
-            },
-        },
-    }
+    std::env::current_dir().unwrap_or_else(|_| {
+        std::env::var("PWD")
+            .map(Into::into)
+            .unwrap_or_else(|_| nu_path::home_dir().unwrap_or_default())
+    })
 }
 
 pub fn get_guaranteed_cwd(engine_state: &EngineState, stack: &Stack) -> PathBuf {
-    match nu_engine::env::current_dir(engine_state, stack) {
-        Ok(p) => p,
-        Err(e) => {
+    nu_engine::env::current_dir(engine_state, stack).unwrap_or_else(|e| {
         let working_set = StateWorkingSet::new(engine_state);
         report_error(&working_set, &e);
         get_init_cwd()
-        }
-    }
+    })
 }
 
 #[cfg(test)]

crates/nu-cli/src/validation.rs

@@ -1,9 +1,10 @@
 use nu_parser::{parse, ParseError};
 use nu_protocol::engine::{EngineState, StateWorkingSet};
 use reedline::{ValidationResult, Validator};
+use std::sync::Arc;
 
 pub struct NuValidator {
-    pub engine_state: EngineState,
+    pub engine_state: Arc<EngineState>,
 }
 
 impl Validator for NuValidator {

crates/nu-cli/tests/completions.rs

@@ -34,6 +34,26 @@ fn completer_strings() -> NuCompleter {
     NuCompleter::new(std::sync::Arc::new(engine), stack)
 }
 
+#[fixture]
+fn extern_completer() -> NuCompleter {
+    // Create a new engine
+    let (dir, _, mut engine, mut stack) = new_engine();
+
+    // Add record value as example
+    let record = r#"
+        def animals [] { [ "cat", "dog", "eel" ] }
+        extern spam [
+            animal: string@animals
+            --foo (-f): string@animals
+            -b: string@animals
+        ]
+    "#;
+    assert!(support::merge_input(record.as_bytes(), &mut engine, &mut stack, dir).is_ok());
+
+    // Instantiate a new completer
+    NuCompleter::new(std::sync::Arc::new(engine), stack)
+}
+
 #[test]
 fn variables_dollar_sign_with_varialblecompletion() {
     let (_, _, engine, stack) = new_engine();
@@ -89,7 +109,7 @@ fn dotnu_completions() {
     // Create a new engine
     let (_, _, engine, stack) = new_engine();
 
-    // Instatiate a new completer
+    // Instantiate a new completer
     let mut completer = NuCompleter::new(std::sync::Arc::new(engine), stack);
 
     // Test source completion
@@ -149,11 +169,11 @@ fn file_completions() {
     // Create a new engine
     let (dir, dir_str, engine, stack) = new_engine();
 
-    // Instatiate a new completer
+    // Instantiate a new completer
     let mut completer = NuCompleter::new(std::sync::Arc::new(engine), stack);
 
     // Test completions for the current folder
-    let target_dir = format!("cp {}", dir_str);
+    let target_dir = format!("cp {dir_str}");
     let suggestions = completer.complete(&target_dir, target_dir.len());
 
     // Create the expected values
@@ -424,6 +444,7 @@ fn file_completion_quoted() {
         "`te st.txt`".to_string(),
         "`te#st.txt`".to_string(),
         "`te'st.txt`".to_string(),
+        "`te(st).txt`".to_string(),
     ];
 
     match_suggestions(expected_paths, suggestions)
@@ -434,12 +455,12 @@ fn flag_completions() {
     // Create a new engine
     let (_, _, engine, stack) = new_engine();
 
-    // Instatiate a new completer
+    // Instantiate a new completer
     let mut completer = NuCompleter::new(std::sync::Arc::new(engine), stack);
     // Test completions for the 'ls' flags
     let suggestions = completer.complete("ls -", 4);
 
-    assert_eq!(14, suggestions.len());
+    assert_eq!(16, suggestions.len());
 
     let expected: Vec<String> = vec![
         "--all".into(),
@@ -448,6 +469,7 @@ fn flag_completions() {
         "--full-paths".into(),
         "--help".into(),
         "--long".into(),
+        "--mime-type".into(),
         "--short-names".into(),
         "-D".into(),
         "-a".into(),
@@ -455,6 +477,7 @@ fn flag_completions() {
         "-f".into(),
         "-h".into(),
         "-l".into(),
+        "-m".into(),
         "-s".into(),
     ];
 
@@ -467,11 +490,11 @@ fn folder_with_directorycompletions() {
     // Create a new engine
     let (dir, dir_str, engine, stack) = new_engine();
 
-    // Instatiate a new completer
+    // Instantiate a new completer
     let mut completer = NuCompleter::new(std::sync::Arc::new(engine), stack);
 
     // Test completions for the current folder
-    let target_dir = format!("cd {}", dir_str);
+    let target_dir = format!("cd {dir_str}");
     let suggestions = completer.complete(&target_dir, target_dir.len());
 
     // Create the expected values
@@ -495,7 +518,7 @@ fn variables_completions() {
     let record = "let actor = { name: 'Tom Hardy', age: 44 }";
     assert!(support::merge_input(record.as_bytes(), &mut engine, &mut stack, dir).is_ok());
 
-    // Instatiate a new completer
+    // Instantiate a new completer
     let mut completer = NuCompleter::new(std::sync::Arc::new(engine), stack);
 
     // Test completions for $nu
@@ -652,7 +675,7 @@ fn run_external_completion(block: &str, input: &str) -> Vec<Suggestion> {
     config.external_completer = Some(latest_block_id);
     engine_state.set_config(&config);
 
-    // Instatiate a new completer
+    // Instantiate a new completer
     let mut completer = NuCompleter::new(std::sync::Arc::new(engine_state), stack);
 
     completer.complete(input, input.len())
@@ -750,3 +773,83 @@ fn filecompletions_triggers_after_cursor() {
 
     match_suggestions(expected_paths, suggestions);
 }
+
+#[rstest]
+fn extern_custom_completion_positional(mut extern_completer: NuCompleter) {
+    let suggestions = extern_completer.complete("spam ", 5);
+    let expected: Vec<String> = vec!["cat".into(), "dog".into(), "eel".into()];
+    match_suggestions(expected, suggestions);
+}
+
+#[rstest]
+fn extern_custom_completion_long_flag_1(mut extern_completer: NuCompleter) {
+    let suggestions = extern_completer.complete("spam --foo=", 11);
+    let expected: Vec<String> = vec!["cat".into(), "dog".into(), "eel".into()];
+    match_suggestions(expected, suggestions);
+}
+
+#[rstest]
+fn extern_custom_completion_long_flag_2(mut extern_completer: NuCompleter) {
+    let suggestions = extern_completer.complete("spam --foo ", 11);
+    let expected: Vec<String> = vec!["cat".into(), "dog".into(), "eel".into()];
+    match_suggestions(expected, suggestions);
+}
+
+#[rstest]
+fn extern_custom_completion_long_flag_short(mut extern_completer: NuCompleter) {
+    let suggestions = extern_completer.complete("spam -f ", 8);
+    let expected: Vec<String> = vec!["cat".into(), "dog".into(), "eel".into()];
+    match_suggestions(expected, suggestions);
+}
+
+#[rstest]
+fn extern_custom_completion_short_flag(mut extern_completer: NuCompleter) {
+    let suggestions = extern_completer.complete("spam -b ", 8);
+    let expected: Vec<String> = vec!["cat".into(), "dog".into(), "eel".into()];
+    match_suggestions(expected, suggestions);
+}
+
+#[rstest]
+fn extern_complete_flags(mut extern_completer: NuCompleter) {
+    let suggestions = extern_completer.complete("spam -", 6);
+    let expected: Vec<String> = vec!["--foo".into(), "-b".into(), "-f".into()];
+    match_suggestions(expected, suggestions);
+}
+
+#[rstest]
+fn alias_offset_bug_7748() {
+    let (dir, _, mut engine, mut stack) = new_engine();
+
+    // Create an alias
+    let alias = r#"alias ea = ^$env.EDITOR /tmp/test.s"#;
+    assert!(support::merge_input(alias.as_bytes(), &mut engine, &mut stack, dir).is_ok());
+
+    let mut completer = NuCompleter::new(std::sync::Arc::new(engine), stack);
+
+    // Issue #7748
+    // Nushell crashes when an alias name is shorter than the alias command
+    // and the alias command is a external command
+    // This happens because of offset is not correct.
+    // This crashes before PR #7779
+    let _suggestions = completer.complete("e", 1);
+    //println!(" --------- suggestions: {:?}", suggestions);
+}
+
+#[rstest]
+fn alias_offset_bug_7754() {
+    let (dir, _, mut engine, mut stack) = new_engine();
+
+    // Create an alias
+    let alias = r#"alias ll = ls -l"#;
+    assert!(support::merge_input(alias.as_bytes(), &mut engine, &mut stack, dir).is_ok());
+
+    let mut completer = NuCompleter::new(std::sync::Arc::new(engine), stack);
+
+    // Issue #7754
+    // Nushell crashes when an alias name is shorter than the alias command
+    // and the alias command contains pipes.
+    // This crashes before PR #7756
+    let _suggestions = completer.complete("ll -a | c", 9);
+
+    //println!(" --------- suggestions: {:?}", suggestions);
+}

crates/nu-color-config/Cargo.toml

@@ -5,18 +5,18 @@ repository = "https://github.com/nushell/nushell/tree/main/crates/nu-color-confi
 edition = "2021"
 license = "MIT"
 name = "nu-color-config"
-version = "0.73.0"
+version = "0.75.0"
 
 [dependencies]
 serde = { version="1.0.123", features=["derive"] }
 # used only for text_style Alignments
 tabled = { version = "0.10.0", features = ["color"], default-features = false }
 
-nu-protocol = { path = "../nu-protocol", version = "0.73.0"  }
+nu-protocol = { path = "../nu-protocol", version = "0.75.0"  }
 nu-ansi-term = "0.46.0"
-nu-utils = { path = "../nu-utils", version = "0.73.0" }
-nu-engine = { path = "../nu-engine", version = "0.73.0" }
-nu-json = { path="../nu-json", version = "0.73.0"  }
+nu-utils = { path = "../nu-utils", version = "0.75.0" }
+nu-engine = { path = "../nu-engine", version = "0.75.0" }
+nu-json = { path="../nu-json", version = "0.75.0"  }
 
 [dev-dependencies]
-nu-test-support = { path="../nu-test-support", version = "0.73.0"  }
+nu-test-support = { path="../nu-test-support", version = "0.75.0"  }

crates/nu-color-config/src/nu_style.rs

@@ -65,7 +65,7 @@ fn color_to_string(color: Color) -> Option<String> {
         Color::White => Some(String::from("white")),
         Color::LightGray => Some(String::from("light_gray")),
         Color::Default => Some(String::from("default")),
-        Color::Rgb(r, g, b) => Some(format!("#{:X}{:X}{:X}", r, g, b)),
+        Color::Rgb(r, g, b) => Some(format!("#{r:X}{g:X}{b:X}")),
         Color::Fixed(_) => None,
     }
 }

crates/nu-color-config/src/shape_color.rs

@@ -1,14 +1,10 @@
-use crate::color_config::lookup_ansi_color_style;
+use crate::{color_config::lookup_ansi_color_style, color_record_to_nustyle};
 use nu_ansi_term::{Color, Style};
-use nu_protocol::Config;
+use nu_protocol::{Config, Value};
 
-pub fn get_shape_color(shape: String, conf: &Config) -> Style {
-    match conf.color_config.get(shape.as_str()) {
-        Some(int_color) => match int_color.as_string() {
-            Ok(int_color) => lookup_ansi_color_style(&int_color),
-            Err(_) => Style::default(),
-        },
-        None => match shape.as_ref() {
+// The default colors for shapes, used when there is no config for them.
+pub fn default_shape_color(shape: String) -> Style {
+    match shape.as_ref() {
         "shape_and" => Style::new().fg(Color::Purple).bold(),
         "shape_binary" => Style::new().fg(Color::Purple).bold(),
         "shape_block" => Style::new().fg(Color::Blue).bold(),
@@ -40,6 +36,21 @@ pub fn get_shape_color(shape: String, conf: &Config) -> Style {
         "shape_table" => Style::new().fg(Color::Blue).bold(),
         "shape_variable" => Style::new().fg(Color::Purple),
         _ => Style::default(),
-        },
+    }
+}
+
+pub fn get_shape_color(shape: String, conf: &Config) -> Style {
+    match conf.color_config.get(shape.as_str()) {
+        Some(int_color) => {
+            // Shapes do not use color_config closures, currently.
+            match int_color {
+                Value::Record { .. } => color_record_to_nustyle(int_color),
+                Value::String { val, .. } => lookup_ansi_color_style(val),
+                // Defer to the default in the event of incorrect types being given
+                // (i.e. treat null, etc. as the value being unset)
+                _ => default_shape_color(shape),
+            }
+        }
+        None => default_shape_color(shape),
     }
 }

crates/nu-color-config/src/style_computer.rs

@@ -126,7 +126,7 @@ impl<'a> StyleComputer<'a> {
 
             Value::Filesize { .. } => TextStyle::with_style(AlignmentHorizontal::Right, s),
 
-            Value::Duration { .. } => TextStyle::with_style(AlignmentHorizontal::Left, s),
+            Value::Duration { .. } => TextStyle::with_style(AlignmentHorizontal::Right, s),
 
             Value::Date { .. } => TextStyle::with_style(AlignmentHorizontal::Left, s),
 
@@ -226,10 +226,10 @@ fn test_computable_style_static() {
     let style2 = Style::default().underline();
     // Create a "dummy" style_computer for this test.
     let dummy_engine_state = EngineState::new();
-    let mut dummy_stack = Stack::new();
+    let dummy_stack = Stack::new();
     let style_computer = StyleComputer::new(
         &dummy_engine_state,
-        &mut dummy_stack,
+        &dummy_stack,
         HashMap::from([
             ("string".into(), ComputableStyle::Static(style1)),
             ("row_index".into(), ComputableStyle::Static(style2)),

crates/nu-command/Cargo.toml

@@ -5,72 +5,74 @@ repository = "https://github.com/nushell/nushell/tree/main/crates/nu-command"
 edition = "2021"
 license = "MIT"
 name = "nu-command"
-version = "0.73.0"
+version = "0.75.0"
 build = "build.rs"
 
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
-nu-color-config = { path = "../nu-color-config", version = "0.73.0"  }
-nu-engine = { path = "../nu-engine", version = "0.73.0"  }
-nu-glob = { path = "../nu-glob", version = "0.73.0" }
-nu-json = { path = "../nu-json", version = "0.73.0"  }
-nu-parser = { path = "../nu-parser", version = "0.73.0"  }
-nu-path = { path = "../nu-path", version = "0.73.0"  }
-nu-pretty-hex = { path = "../nu-pretty-hex", version = "0.73.0"  }
-nu-protocol = { path = "../nu-protocol", version = "0.73.0"  }
-nu-system = { path = "../nu-system", version = "0.73.0"  }
-nu-table = { path = "../nu-table", version = "0.73.0"  }
-nu-term-grid = { path = "../nu-term-grid", version = "0.73.0"  }
-nu-utils = { path = "../nu-utils", version = "0.73.0" }
-nu-explore = { path = "../nu-explore", version = "0.73.0" }
+nu-color-config = { path = "../nu-color-config", version = "0.75.0" }
+nu-engine = { path = "../nu-engine", version = "0.75.0" }
+nu-glob = { path = "../nu-glob", version = "0.75.0" }
+nu-json = { path = "../nu-json", version = "0.75.0" }
+nu-parser = { path = "../nu-parser", version = "0.75.0" }
+nu-path = { path = "../nu-path", version = "0.75.0" }
+nu-pretty-hex = { path = "../nu-pretty-hex", version = "0.75.0" }
+nu-protocol = { path = "../nu-protocol", version = "0.75.0" }
+nu-system = { path = "../nu-system", version = "0.75.0" }
+nu-table = { path = "../nu-table", version = "0.75.0" }
+nu-term-grid = { path = "../nu-term-grid", version = "0.75.0" }
+nu-utils = { path = "../nu-utils", version = "0.75.0" }
+nu-explore = { path = "../nu-explore", version = "0.75.0" }
 nu-ansi-term = "0.46.0"
 num-format = { version = "0.4.3" }
 
 # Potential dependencies for extras
 alphanumeric-sort = "1.4.4"
 atty = "0.2.14"
-base64 = "0.13.0"
+base64 = "0.21.0"
 byteorder = "1.4.3"
 bytesize = "1.1.0"
 calamine = "0.19.1"
 chrono = { version = "0.4.23", features = ["unstable-locales", "std"], default-features = false }
 chrono-humanize = "0.2.1"
-chrono-tz = "0.6.3"
+chrono-tz = "0.8.1"
 crossterm = "0.24.0"
 csv = "1.1.6"
-dialoguer = { default-features = false, version = "0.9.0" }
+dialoguer = { default-features = false, version = "0.10.3" }
 digest = { default-features = false, version = "0.10.0" }
 dtparse = "1.2.0"
 eml-parser = "0.1.0"
 encoding_rs = "0.8.30"
-fancy-regex = "0.10.0"
+fancy-regex = "0.11.0"
 filesize = "0.2.0"
 filetime = "0.2.15"
 fs_extra = "1.2.0"
 htmlescape = "0.3.1"
 ical = "0.7.0"
 indexmap = { version = "1.7", features = ["serde-1"] }
+indicatif = "0.17.2"
 Inflector = "0.11"
 is-root = "0.1.2"
 itertools = "0.10.0"
 log = "0.4.14"
 lscolors = { version = "0.12.0", features = ["crossterm"], default-features = false }
 md5 = { package = "md-5", version = "0.10.0" }
-meval = "0.2.0"
 mime = "0.3.16"
+mime_guess = "2.0.4"
 notify = "4.0.17"
 num = { version = "0.4.0", optional = true }
 num-traits = "0.2.14"
-once_cell = "1.0"
+once_cell = "1.17"
+open = "3.2.0"
 pathdiff = "0.2.1"
-powierza-coefficient = "1.0.1"
-quick-xml = "0.25"
+powierza-coefficient = "1.0.2"
+quick-xml = "0.27"
 rand = "0.8"
-rayon = "1.5.1"
-regex = "1.6.0"
+rayon = "1.6.1"
+regex = "1.7.1"
 reqwest = { version = "0.11", features = ["blocking", "json"] }
-roxmltree = "0.16.0"
+roxmltree = "0.17.0"
 rust-embed = "6.3.0"
 same-file = "1.0.6"
 serde = { version = "1.0.123", features = ["derive"] }
@@ -79,20 +81,21 @@ serde_urlencoded = "0.7.0"
 serde_yaml = "0.9.4"
 sha2 = "0.10.0"
 # Disable default features b/c the default features build Git (very slow to compile)
-shadow-rs = { version = "0.16.1", default-features = false }
-sysinfo = "0.26.2"
+shadow-rs = { version = "0.20.0", default-features = false }
+sysinfo = "0.27.7"
 terminal_size = "0.2.1"
 thiserror = "1.0.31"
 titlecase = "2.0.0"
 toml = "0.5.8"
 unicode-segmentation = "1.8.0"
 url = "2.2.1"
-uuid = { version = "1.1.2", features = ["v4"] }
+percent-encoding = "2.2.0"
+uuid = { version = "1.2.2", features = ["v4"] }
 which = { version = "4.3.0", optional = true }
-reedline = { version = "0.14.0", features = ["bashisms", "sqlite"]}
+reedline = { version = "0.15.0", features = ["bashisms", "sqlite"] }
 wax = { version = "0.5.0" }
 rusqlite = { version = "0.28.0", features = ["bundled"], optional = true }
-sqlparser = { version = "0.23.0", features = ["serde"], optional = true }
+sqlparser = { version = "0.30.0", features = ["serde"], optional = true }
 
 [target.'cfg(windows)'.dependencies]
 winreg = "0.10.1"
@@ -103,11 +106,11 @@ users = "0.11.0"
 libc = "0.2"
 
 [target.'cfg(not(any(target_os = "android", target_os = "ios")))'.dependencies.trash]
-version = "3.0.0"
+version = "3.0.1"
 optional = true
 
 [dependencies.polars]
-version = "0.25.0"
+version = "0.26.1"
 optional = true
 features = [
 	"arg_where",
@@ -138,12 +141,8 @@ features = [
 ]
 
 [target.'cfg(windows)'.dependencies.windows]
-version = "0.43.0"
-features = [
-    "Win32_Foundation",
-    "Win32_Storage_FileSystem",
-	"Win32_System_SystemServices",
-]
+version = "0.44.0"
+features = ["Win32_Foundation", "Win32_Storage_FileSystem", "Win32_System_SystemServices"]
 
 [features]
 trash-support = ["trash"]
@@ -153,10 +152,10 @@ dataframe = ["polars", "num", "sqlparser"]
 sqlite = ["rusqlite"]                      # TODO: given that rusqlite is included in reedline, should we just always include it?
 
 [build-dependencies]
-shadow-rs = { version = "0.16.1", default-features = false }
+shadow-rs = { version = "0.20.0", default-features = false }
 
 [dev-dependencies]
-nu-test-support = { path = "../nu-test-support", version = "0.73.0"  }
+nu-test-support = { path = "../nu-test-support", version = "0.75.0" }
 
 hamcrest2 = "0.3.0"
 dirs-next = "2.0.0"

crates/nu-command/build.rs

@@ -4,7 +4,7 @@ fn main() -> shadow_rs::SdResult<()> {
     // Look up the current Git commit ourselves instead of relying on shadow_rs,
     // because shadow_rs does it in a really slow-to-compile way (it builds libgit2)
     let hash = get_git_hash().unwrap_or_default();
-    println!("cargo:rustc-env=NU_COMMIT_HASH={}", hash);
+    println!("cargo:rustc-env=NU_COMMIT_HASH={hash}");
 
     shadow_rs::new()
 }

crates/nu-command/src/bits/and.rs

@@ -43,6 +43,10 @@ impl Command for SubCommand {
         let head = call.head;
         let target: i64 = call.req(engine_state, stack, 0)?;
 
+        // This doesn't match explicit nulls
+        if matches!(input, PipelineData::Empty) {
+            return Err(ShellError::PipelineEmpty(head));
+        }
         input.map(
             move |value| operate(value, target, head),
             engine_state.ctrlc.clone(),
@@ -54,7 +58,7 @@ impl Command for SubCommand {
             Example {
                 description: "Apply bits and to two numbers",
                 example: "2 | bits and 2",
-                result: Some(Value::int(2, Span::test_data())),
+                result: Some(Value::test_int(2)),
             },
             Example {
                 description: "Apply logical and to a list of numbers",
@@ -74,13 +78,15 @@ fn operate(value: Value, target: i64, head: Span) -> Value {
             val: val & target,
             span,
         },
+        // Propagate errors by explicitly matching them before the final case.
+        Value::Error { .. } => value,
         other => Value::Error {
-            error: ShellError::UnsupportedInput(
-                format!(
-                    "Only integer values are supported, input type: {:?}",
-                    other.get_type()
-                ),
-                other.span().unwrap_or(head),
+            error: ShellError::OnlySupportsThisInputType(
+                "integer".into(),
+                other.get_type().to_string(),
+                head,
+                // This line requires the Value::Error match above.
+                other.expect_span(),
             ),
         },
     }

crates/nu-command/src/bits/bits_.rs

@@ -2,7 +2,7 @@ use nu_engine::get_full_help;
 use nu_protocol::{
     ast::Call,
     engine::{Command, EngineState, Stack},
-    Category, IntoPipelineData, PipelineData, Signature, Value,
+    Category, IntoPipelineData, PipelineData, Signature, Type, Value,
 };
 
 #[derive(Clone)]
@@ -14,13 +14,19 @@ impl Command for Bits {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("bits").category(Category::Bits)
+        Signature::build("bits")
+            .category(Category::Bits)
+            .input_output_types(vec![(Type::Nothing, Type::String)])
     }
 
     fn usage(&self) -> &str {
         "Various commands for working with bits"
     }
 
+    fn extra_usage(&self) -> &str {
+        "You must use one of the following subcommands. Using this command as-is will only produce this help message."
+    }
+
     fn run(
         &self,
         engine_state: &EngineState,
@@ -41,15 +47,3 @@ impl Command for Bits {
         .into_pipeline_data())
     }
 }
-
-#[cfg(test)]
-mod test {
-    use crate::Bits;
-
-    #[test]
-    fn test_examples() {
-        use crate::test_examples;
-
-        test_examples(Bits {})
-    }
-}

crates/nu-command/src/bits/not.rs

@@ -56,11 +56,17 @@ impl Command for SubCommand {
             if let Some(val) = number_bytes {
                 return Err(ShellError::UnsupportedInput(
                     "Only 1, 2, 4, 8, or 'auto' bytes are supported as word sizes".to_string(),
+                    "value originates from here".to_string(),
+                    head,
                     val.span,
                 ));
             }
         }
 
+        // This doesn't match explicit nulls
+        if matches!(input, PipelineData::Empty) {
+            return Err(ShellError::PipelineEmpty(head));
+        }
         input.map(
             move |value| operate(value, head, signed, bytes_len),
             engine_state.ctrlc.clone(),
@@ -140,15 +146,18 @@ fn operate(value: Value, head: Span, signed: bool, number_size: NumberBytes) ->
                 Value::Int { val: out_val, span }
             }
         }
-        other => Value::Error {
-            error: ShellError::UnsupportedInput(
-                format!(
-                    "Only numerical values are supported, input type: {:?}",
-                    other.get_type()
-                ),
-                other.span().unwrap_or(head),
+        other => match other {
+            // Propagate errors inside the value
+            Value::Error { .. } => other,
+            _ => Value::Error {
+                error: ShellError::OnlySupportsThisInputType(
+                    "numeric".into(),
+                    other.get_type().to_string(),
+                    head,
+                    other.expect_span(),
                 ),
             },
+        },
     }
 }
 

crates/nu-command/src/bits/or.rs

@@ -43,6 +43,10 @@ impl Command for SubCommand {
         let head = call.head;
         let target: i64 = call.req(engine_state, stack, 0)?;
 
+        // This doesn't match explicit nulls
+        if matches!(input, PipelineData::Empty) {
+            return Err(ShellError::PipelineEmpty(head));
+        }
         input.map(
             move |value| operate(value, target, head),
             engine_state.ctrlc.clone(),
@@ -54,7 +58,7 @@ impl Command for SubCommand {
             Example {
                 description: "Apply bits or to two numbers",
                 example: "2 | bits or 6",
-                result: Some(Value::int(6, Span::test_data())),
+                result: Some(Value::test_int(6)),
             },
             Example {
                 description: "Apply logical or to a list of numbers",
@@ -74,13 +78,15 @@ fn operate(value: Value, target: i64, head: Span) -> Value {
             val: val | target,
             span,
         },
+        // Propagate errors by explicitly matching them before the final case.
+        Value::Error { .. } => value,
         other => Value::Error {
-            error: ShellError::UnsupportedInput(
-                format!(
-                    "Only integer values are supported, input type: {:?}",
-                    other.get_type()
-                ),
-                other.span().unwrap_or(head),
+            error: ShellError::OnlySupportsThisInputType(
+                "integer".into(),
+                other.get_type().to_string(),
+                head,
+                // This line requires the Value::Error match above.
+                other.expect_span(),
             ),
         },
     }

crates/nu-command/src/bits/rotate_left.rs

@@ -60,11 +60,16 @@ impl Command for SubCommand {
             if let Some(val) = number_bytes {
                 return Err(ShellError::UnsupportedInput(
                     "Only 1, 2, 4, 8, or 'auto' bytes are supported as word sizes".to_string(),
+                    "value originates from here".to_string(),
+                    head,
                     val.span,
                 ));
             }
         }
-
+        // This doesn't match explicit nulls
+        if matches!(input, PipelineData::Empty) {
+            return Err(ShellError::PipelineEmpty(head));
+        }
         input.map(
             move |value| operate(value, bits, head, signed, bytes_len),
             engine_state.ctrlc.clone(),
@@ -76,7 +81,7 @@ impl Command for SubCommand {
             Example {
                 description: "Rotate left a number with 2 bits",
                 example: "17 | bits rol 2",
-                result: Some(Value::int(68, Span::test_data())),
+                result: Some(Value::test_int(68)),
             },
             Example {
                 description: "Rotate left a list of numbers with 2 bits",
@@ -101,8 +106,7 @@ where
             error: ShellError::GenericError(
                 "Rotate left result beyond the range of 64 bit signed number".to_string(),
                 format!(
-                    "{} of the specified number of bytes rotate left {} bits exceed limit",
-                    val, bits
+                    "{val} of the specified number of bytes rotate left {bits} bits exceed limit"
                 ),
                 Some(span),
                 None,
@@ -127,16 +131,18 @@ fn operate(value: Value, bits: usize, head: Span, signed: bool, number_size: Num
                 SignedOne => get_rotate_left(val as i8, bits, span),
                 SignedTwo => get_rotate_left(val as i16, bits, span),
                 SignedFour => get_rotate_left(val as i32, bits, span),
-                SignedEight => get_rotate_left(val as i64, bits, span),
+                SignedEight => get_rotate_left(val, bits, span),
             }
         }
+        // Propagate errors by explicitly matching them before the final case.
+        Value::Error { .. } => value,
         other => Value::Error {
-            error: ShellError::UnsupportedInput(
-                format!(
-                    "Only integer values are supported, input type: {:?}",
-                    other.get_type()
-                ),
-                other.span().unwrap_or(head),
+            error: ShellError::OnlySupportsThisInputType(
+                "integer".into(),
+                other.get_type().to_string(),
+                head,
+                // This line requires the Value::Error match above.
+                other.expect_span(),
             ),
         },
     }

crates/nu-command/src/bits/rotate_right.rs

@@ -60,11 +60,16 @@ impl Command for SubCommand {
             if let Some(val) = number_bytes {
                 return Err(ShellError::UnsupportedInput(
                     "Only 1, 2, 4, 8, or 'auto' bytes are supported as word sizes".to_string(),
+                    "value originates from here".to_string(),
+                    head,
                     val.span,
                 ));
             }
         }
-
+        // This doesn't match explicit nulls
+        if matches!(input, PipelineData::Empty) {
+            return Err(ShellError::PipelineEmpty(head));
+        }
         input.map(
             move |value| operate(value, bits, head, signed, bytes_len),
             engine_state.ctrlc.clone(),
@@ -76,7 +81,7 @@ impl Command for SubCommand {
             Example {
                 description: "Rotate right a number with 60 bits",
                 example: "17 | bits ror 60",
-                result: Some(Value::int(272, Span::test_data())),
+                result: Some(Value::test_int(272)),
             },
             Example {
                 description: "Rotate right a list of numbers of one byte",
@@ -105,8 +110,7 @@ where
             error: ShellError::GenericError(
                 "Rotate right result beyond the range of 64 bit signed number".to_string(),
                 format!(
-                    "{} of the specified number of bytes rotate right {} bits exceed limit",
-                    val, bits
+                    "{val} of the specified number of bytes rotate right {bits} bits exceed limit"
                 ),
                 Some(span),
                 None,
@@ -131,16 +135,18 @@ fn operate(value: Value, bits: usize, head: Span, signed: bool, number_size: Num
                 SignedOne => get_rotate_right(val as i8, bits, span),
                 SignedTwo => get_rotate_right(val as i16, bits, span),
                 SignedFour => get_rotate_right(val as i32, bits, span),
-                SignedEight => get_rotate_right(val as i64, bits, span),
+                SignedEight => get_rotate_right(val, bits, span),
             }
         }
+        // Propagate errors by explicitly matching them before the final case.
+        Value::Error { .. } => value,
         other => Value::Error {
-            error: ShellError::UnsupportedInput(
-                format!(
-                    "Only integer values are supported, input type: {:?}",
-                    other.get_type()
-                ),
-                other.span().unwrap_or(head),
+            error: ShellError::OnlySupportsThisInputType(
+                "integer".into(),
+                other.get_type().to_string(),
+                head,
+                // This line requires the Value::Error match above.
+                other.expect_span(),
             ),
         },
     }

crates/nu-command/src/bits/shift_left.rs

@@ -60,11 +60,16 @@ impl Command for SubCommand {
             if let Some(val) = number_bytes {
                 return Err(ShellError::UnsupportedInput(
                     "Only 1, 2, 4, 8, or 'auto' bytes are supported as word sizes".to_string(),
+                    "value originates from here".to_string(),
+                    head,
                     val.span,
                 ));
             }
         }
-
+        // This doesn't match explicit nulls
+        if matches!(input, PipelineData::Empty) {
+            return Err(ShellError::PipelineEmpty(head));
+        }
         input.map(
             move |value| operate(value, bits, head, signed, bytes_len),
             engine_state.ctrlc.clone(),
@@ -76,17 +81,17 @@ impl Command for SubCommand {
             Example {
                 description: "Shift left a number by 7 bits",
                 example: "2 | bits shl 7",
-                result: Some(Value::int(256, Span::test_data())),
+                result: Some(Value::test_int(256)),
             },
             Example {
                 description: "Shift left a number with 1 byte by 7 bits",
                 example: "2 | bits shl 7 -n 1",
-                result: Some(Value::int(0, Span::test_data())),
+                result: Some(Value::test_int(0)),
             },
             Example {
                 description: "Shift left a signed number by 1 bit",
                 example: "0x7F | bits shl 1 -s",
-                result: Some(Value::int(254, Span::test_data())),
+                result: Some(Value::test_int(254)),
             },
             Example {
                 description: "Shift left a list of numbers",
@@ -113,8 +118,7 @@ where
                     error: ShellError::GenericError(
                         "Shift left result beyond the range of 64 bit signed number".to_string(),
                         format!(
-                            "{} of the specified number of bytes shift left {} bits exceed limit",
-                            val, bits
+                            "{val} of the specified number of bytes shift left {bits} bits exceed limit"
                         ),
                         Some(span),
                         None,
@@ -126,10 +130,7 @@ where
         None => Value::Error {
             error: ShellError::GenericError(
                 "Shift left failed".to_string(),
-                format!(
-                    "{} shift left {} bits failed, you may shift too many bits",
-                    val, bits
-                ),
+                format!("{val} shift left {bits} bits failed, you may shift too many bits"),
                 Some(span),
                 None,
                 Vec::new(),
@@ -153,16 +154,18 @@ fn operate(value: Value, bits: usize, head: Span, signed: bool, number_size: Num
                 SignedOne => get_shift_left(val as i8, bits, span),
                 SignedTwo => get_shift_left(val as i16, bits, span),
                 SignedFour => get_shift_left(val as i32, bits, span),
-                SignedEight => get_shift_left(val as i64, bits, span),
+                SignedEight => get_shift_left(val, bits, span),
             }
         }
+        // Propagate errors by explicitly matching them before the final case.
+        Value::Error { .. } => value,
         other => Value::Error {
-            error: ShellError::UnsupportedInput(
-                format!(
-                    "Only integer values are supported, input type: {:?}",
-                    other.get_type()
-                ),
-                other.span().unwrap_or(head),
+            error: ShellError::OnlySupportsThisInputType(
+                "integer".into(),
+                other.get_type().to_string(),
+                head,
+                // This line requires the Value::Error match above.
+                other.expect_span(),
             ),
         },
     }

crates/nu-command/src/bits/shift_right.rs

@@ -60,11 +60,16 @@ impl Command for SubCommand {
             if let Some(val) = number_bytes {
                 return Err(ShellError::UnsupportedInput(
                     "Only 1, 2, 4, 8, or 'auto' bytes are supported as word sizes".to_string(),
+                    "value originates from here".to_string(),
+                    head,
                     val.span,
                 ));
             }
         }
-
+        // This doesn't match explicit nulls
+        if matches!(input, PipelineData::Empty) {
+            return Err(ShellError::PipelineEmpty(head));
+        }
         input.map(
             move |value| operate(value, bits, head, signed, bytes_len),
             engine_state.ctrlc.clone(),
@@ -76,7 +81,7 @@ impl Command for SubCommand {
             Example {
                 description: "Shift right a number with 2 bits",
                 example: "8 | bits shr 2",
-                result: Some(Value::int(2, Span::test_data())),
+                result: Some(Value::test_int(2)),
             },
             Example {
                 description: "Shift right a list of numbers",
@@ -103,8 +108,7 @@ where
                     error: ShellError::GenericError(
                         "Shift right result beyond the range of 64 bit signed number".to_string(),
                         format!(
-                            "{} of the specified number of bytes shift right {} bits exceed limit",
-                            val, bits
+                            "{val} of the specified number of bytes shift right {bits} bits exceed limit"
                         ),
                         Some(span),
                         None,
@@ -116,10 +120,7 @@ where
         None => Value::Error {
             error: ShellError::GenericError(
                 "Shift right failed".to_string(),
-                format!(
-                    "{} shift right {} bits failed, you may shift too many bits",
-                    val, bits
-                ),
+                format!("{val} shift right {bits} bits failed, you may shift too many bits"),
                 Some(span),
                 None,
                 Vec::new(),
@@ -143,16 +144,18 @@ fn operate(value: Value, bits: usize, head: Span, signed: bool, number_size: Num
                 SignedOne => get_shift_right(val as i8, bits, span),
                 SignedTwo => get_shift_right(val as i16, bits, span),
                 SignedFour => get_shift_right(val as i32, bits, span),
-                SignedEight => get_shift_right(val as i64, bits, span),
+                SignedEight => get_shift_right(val, bits, span),
             }
         }
+        // Propagate errors by explicitly matching them before the final case.
+        Value::Error { .. } => value,
         other => Value::Error {
-            error: ShellError::UnsupportedInput(
-                format!(
-                    "Only integer values are supported, input type: {:?}",
-                    other.get_type()
-                ),
-                other.span().unwrap_or(head),
+            error: ShellError::OnlySupportsThisInputType(
+                "integer".into(),
+                other.get_type().to_string(),
+                head,
+                // This line requires the Value::Error match above.
+                other.expect_span(),
             ),
         },
     }

crates/nu-command/src/bits/xor.rs

@@ -42,7 +42,10 @@ impl Command for SubCommand {
     ) -> Result<nu_protocol::PipelineData, nu_protocol::ShellError> {
         let head = call.head;
         let target: i64 = call.req(engine_state, stack, 0)?;
-
+        // This doesn't match explicit nulls
+        if matches!(input, PipelineData::Empty) {
+            return Err(ShellError::PipelineEmpty(head));
+        }
         input.map(
             move |value| operate(value, target, head),
             engine_state.ctrlc.clone(),
@@ -54,7 +57,7 @@ impl Command for SubCommand {
             Example {
                 description: "Apply bits xor to two numbers",
                 example: "2 | bits xor 2",
-                result: Some(Value::int(0, Span::test_data())),
+                result: Some(Value::test_int(0)),
             },
             Example {
                 description: "Apply logical xor to a list of numbers",
@@ -74,13 +77,15 @@ fn operate(value: Value, target: i64, head: Span) -> Value {
             val: val ^ target,
             span,
         },
+        // Propagate errors by explicitly matching them before the final case.
+        Value::Error { .. } => value,
         other => Value::Error {
-            error: ShellError::UnsupportedInput(
-                format!(
-                    "Only integer values are supported, input type: {:?}",
-                    other.get_type()
-                ),
-                other.span().unwrap_or(head),
+            error: ShellError::OnlySupportsThisInputType(
+                "integer".into(),
+                other.get_type().to_string(),
+                head,
+                // This line requires the Value::Error match above.
+                other.expect_span(),
             ),
         },
     }

crates/nu-command/src/bytes/add.rs

@@ -122,13 +122,15 @@ fn add(val: &Value, args: &Arguments, span: Span) -> Value {
             val,
             span: val_span,
         } => add_impl(val, args, *val_span),
+        // Propagate errors by explicitly matching them before the final case.
+        Value::Error { .. } => val.clone(),
         other => Value::Error {
-            error: ShellError::UnsupportedInput(
-                format!(
-                    "Input's type is {}. This command only works with bytes.",
-                    other.get_type()
-                ),
+            error: ShellError::OnlySupportsThisInputType(
+                "integer".into(),
+                other.get_type().to_string(),
                 span,
+                // This line requires the Value::Error match above.
+                other.expect_span(),
             ),
         },
     }

crates/nu-command/src/bytes/at.rs

@@ -30,7 +30,9 @@ fn parse_range(range: Value, head: Span) -> Result<(isize, isize, Span), ShellEr
         Value::List { mut vals, span } => {
             if vals.len() != 2 {
                 return Err(ShellError::UnsupportedInput(
-                    "More than two indices given".to_string(),
+                    "More than two indices in range".to_string(),
+                    "value originates from here".to_string(),
+                    head,
                     span,
                 ));
             } else {
@@ -38,10 +40,14 @@ fn parse_range(range: Value, head: Span) -> Result<(isize, isize, Span), ShellEr
                 let end = match end {
                     Value::Int { val, .. } => val.to_string(),
                     Value::String { val, .. } => val,
+                    // Explicitly propagate errors instead of dropping them.
+                    Value::Error { error } => return Err(error),
                     other => {
                         return Err(ShellError::UnsupportedInput(
-                            "could not perform subbytes. Expecting a string or int".to_string(),
-                            other.span().unwrap_or(head),
+                            "Only string or list<int> ranges are supported".into(),
+                            format!("input type: {:?}", other.get_type()),
+                            head,
+                            other.expect_span(),
                         ))
                     }
                 };
@@ -49,10 +55,14 @@ fn parse_range(range: Value, head: Span) -> Result<(isize, isize, Span), ShellEr
                 let start = match start {
                     Value::Int { val, .. } => val.to_string(),
                     Value::String { val, .. } => val,
+                    // Explicitly propagate errors instead of dropping them.
+                    Value::Error { error } => return Err(error),
                     other => {
                         return Err(ShellError::UnsupportedInput(
-                            "could not perform subbytes. Expecting a string or int".to_string(),
-                            other.span().unwrap_or(head),
+                            "Only string or list<int> ranges are supported".into(),
+                            format!("input type: {:?}", other.get_type()),
+                            head,
+                            other.expect_span(),
                         ))
                     }
                 };
@@ -60,21 +70,27 @@ fn parse_range(range: Value, head: Span) -> Result<(isize, isize, Span), ShellEr
             }
         }
         Value::String { val, span } => {
-            let splitted_result = val.split_once(',');
-            match splitted_result {
+            let split_result = val.split_once(',');
+            match split_result {
                 Some((start, end)) => (start.to_string(), end.to_string(), span),
                 None => {
                     return Err(ShellError::UnsupportedInput(
                         "could not perform subbytes".to_string(),
+                        "with this range".to_string(),
+                        head,
                         span,
                     ))
                 }
             }
         }
+        // Explicitly propagate errors instead of dropping them.
+        Value::Error { error } => return Err(error),
         other => {
             return Err(ShellError::UnsupportedInput(
                 "could not perform subbytes".to_string(),
-                other.span().unwrap_or(head),
+                "with this range".to_string(),
+                head,
+                other.expect_span(),
             ))
         }
     };
@@ -82,28 +98,26 @@ fn parse_range(range: Value, head: Span) -> Result<(isize, isize, Span), ShellEr
     let start: isize = if start.is_empty() || start == "_" {
         0
     } else {
-        match start.trim().parse() {
-            Ok(s) => s,
-            Err(_) => {
-                return Err(ShellError::UnsupportedInput(
+        start.trim().parse().map_err(|_| {
+            ShellError::UnsupportedInput(
                 "could not perform subbytes".to_string(),
+                "with this range".to_string(),
+                head,
                 span,
-                ))
-            }
-        }
+            )
+        })?
     };
     let end: isize = if end.is_empty() || end == "_" {
         isize::max_value()
     } else {
-        match end.trim().parse() {
-            Ok(s) => s,
-            Err(_) => {
-                return Err(ShellError::UnsupportedInput(
+        end.trim().parse().map_err(|_| {
+            ShellError::UnsupportedInput(
                 "could not perform subbytes".to_string(),
+                "with this range".to_string(),
+                head,
                 span,
-                ))
-            }
-        }
+            )
+        })?
     };
     Ok((start, end, span))
 }
@@ -232,13 +246,15 @@ fn at(val: &Value, args: &Arguments, span: Span) -> Value {
             val,
             span: val_span,
         } => at_impl(val, args, *val_span),
+        // Propagate errors by explicitly matching them before the final case.
+        Value::Error { .. } => val.clone(),
         other => Value::Error {
-            error: ShellError::UnsupportedInput(
-                format!(
-                    "Input's type is {}. This command only works with bytes.",
-                    other.get_type()
-                ),
+            error: ShellError::OnlySupportsThisInputType(
+                "integer".into(),
+                other.get_type().to_string(),
                 span,
+                // This line requires the Value::Error match above.
+                other.expect_span(),
             ),
         },
     }
@@ -262,7 +278,7 @@ fn at_impl(input: &[u8], arg: &Arguments, span: Span) -> Value {
         match start.cmp(&end) {
             Ordering::Equal => Value::Binary { val: vec![], span },
             Ordering::Greater => Value::Error {
-                error: ShellError::UnsupportedInput(
+                error: ShellError::TypeMismatch(
                     "End must be greater than or equal to Start".to_string(),
                     arg.arg_span,
                 ),

crates/nu-command/src/bytes/build_.rs

@@ -52,10 +52,12 @@ impl Command for BytesBuild {
             let val = eval_expression(engine_state, stack, expr)?;
             match val {
                 Value::Binary { mut val, .. } => output.append(&mut val),
+                // Explicitly propagate errors instead of dropping them.
+                Value::Error { error } => return Err(error),
                 other => {
-                    return Err(ShellError::UnsupportedInput(
-                        "only support expression which yields to binary data".to_string(),
-                        other.span().unwrap_or(call.head),
+                    return Err(ShellError::TypeMismatch(
+                        "only binary data arguments are supported".to_string(),
+                        other.expect_span(),
                     ))
                 }
             }

crates/nu-command/src/bytes/bytes_.rs

@@ -2,7 +2,7 @@ use nu_engine::get_full_help;
 use nu_protocol::{
     ast::Call,
     engine::{Command, EngineState, Stack},
-    Category, IntoPipelineData, PipelineData, Signature, Value,
+    Category, IntoPipelineData, PipelineData, Signature, Type, Value,
 };
 
 #[derive(Clone)]
@@ -14,13 +14,19 @@ impl Command for Bytes {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("bytes").category(Category::Bytes)
+        Signature::build("bytes")
+            .category(Category::Bytes)
+            .input_output_types(vec![(Type::Nothing, Type::String)])
     }
 
     fn usage(&self) -> &str {
         "Various commands for working with byte data"
     }
 
+    fn extra_usage(&self) -> &str {
+        "You must use one of the following subcommands. Using this command as-is will only produce this help message."
+    }
+
     fn run(
         &self,
         engine_state: &EngineState,
@@ -41,15 +47,3 @@ impl Command for Bytes {
         .into_pipeline_data())
     }
 }
-
-#[cfg(test)]
-mod test {
-    use crate::Bytes;
-
-    #[test]
-    fn test_examples() {
-        use crate::test_examples;
-
-        test_examples(Bytes {})
-    }
-}

crates/nu-command/src/bytes/collect.rs

@@ -54,14 +54,16 @@ impl Command for BytesCollect {
                         output_binary.append(&mut work_sep)
                     }
                 }
+                // Explicitly propagate errors instead of dropping them.
+                Value::Error { error } => return Err(error),
                 other => {
-                    return Err(ShellError::UnsupportedInput(
-                        format!(
-                            "The element type is {}, this command only works with bytes.",
-                            other.get_type()
-                        ),
-                        other.span().unwrap_or(call.head),
-                    ))
+                    return Err(ShellError::OnlySupportsThisInputType(
+                        "integer".into(),
+                        other.get_type().to_string(),
+                        call.head,
+                        // This line requires the Value::Error match above.
+                        other.expect_span(),
+                    ));
                 }
             }
         }

crates/nu-command/src/bytes/ends_with.rs

@@ -68,17 +68,17 @@ impl Command for BytesEndsWith {
             Example {
                 description: "Checks if binary ends with `0x[AA]`",
                 example: "0x[1F FF AA AA] | bytes ends-with 0x[AA]",
-                result: Some(Value::boolean(true, Span::test_data())),
+                result: Some(Value::test_bool(true)),
             },
             Example {
                 description: "Checks if binary ends with `0x[FF AA AA]`",
                 example: "0x[1F FF AA AA] | bytes ends-with 0x[FF AA AA]",
-                result: Some(Value::boolean(true, Span::test_data())),
+                result: Some(Value::test_bool(true)),
             },
             Example {
                 description: "Checks if binary ends with `0x[11]`",
                 example: "0x[1F FF AA AA] | bytes ends-with 0x[11]",
-                result: Some(Value::boolean(false, Span::test_data())),
+                result: Some(Value::test_bool(false)),
             },
         ]
     }
@@ -90,13 +90,15 @@ fn ends_with(val: &Value, args: &Arguments, span: Span) -> Value {
             val,
             span: val_span,
         } => Value::boolean(val.ends_with(&args.pattern), *val_span),
+        // Propagate errors by explicitly matching them before the final case.
+        Value::Error { .. } => val.clone(),
         other => Value::Error {
-            error: ShellError::UnsupportedInput(
-                format!(
-                    "Input's type is {}. This command only works with bytes.",
-                    other.get_type()
-                ),
+            error: ShellError::OnlySupportsThisInputType(
+                "binary".into(),
+                other.get_type().to_string(),
                 span,
+                // This line requires the Value::Error match above.
+                other.expect_span(),
             ),
         },
     }

crates/nu-command/src/bytes/index_of.rs

@@ -132,13 +132,15 @@ fn index_of(val: &Value, args: &Arguments, span: Span) -> Value {
             val,
             span: val_span,
         } => index_of_impl(val, args, *val_span),
+        // Propagate errors by explicitly matching them before the final case.
+        Value::Error { .. } => val.clone(),
         other => Value::Error {
-            error: ShellError::UnsupportedInput(
-                format!(
-                    "Input's type is {}. This command only works with bytes.",
-                    other.get_type()
-                ),
+            error: ShellError::OnlySupportsThisInputType(
+                "binary".into(),
+                other.get_type().to_string(),
                 span,
+                // This line requires the Value::Error match above.
+                other.expect_span(),
             ),
         },
     }

crates/nu-command/src/bytes/length.rs

@@ -71,13 +71,15 @@ fn length(val: &Value, _args: &CellPathOnlyArgs, span: Span) -> Value {
             val,
             span: val_span,
         } => Value::int(val.len() as i64, *val_span),
+        // Propagate errors by explicitly matching them before the final case.
+        Value::Error { .. } => val.clone(),
         other => Value::Error {
-            error: ShellError::UnsupportedInput(
-                format!(
-                    "Input's type is {}. This command only works with bytes.",
-                    other.get_type()
-                ),
+            error: ShellError::OnlySupportsThisInputType(
+                "binary".into(),
+                other.get_type().to_string(),
                 span,
+                // This line requires the Value::Error match above.
+                other.expect_span(),
             ),
         },
     }

crates/nu-command/src/bytes/remove.rs

@@ -61,7 +61,7 @@ impl Command for BytesRemove {
         let cell_paths = (!cell_paths.is_empty()).then_some(cell_paths);
         let pattern_to_remove = call.req::<Spanned<Vec<u8>>>(engine_state, stack, 0)?;
         if pattern_to_remove.item.is_empty() {
-            return Err(ShellError::UnsupportedInput(
+            return Err(ShellError::TypeMismatch(
                 "the pattern to remove cannot be empty".to_string(),
                 pattern_to_remove.span,
             ));
@@ -139,13 +139,15 @@ fn remove(val: &Value, args: &Arguments, span: Span) -> Value {
             val,
             span: val_span,
         } => remove_impl(val, args, *val_span),
+        // Propagate errors by explicitly matching them before the final case.
+        Value::Error { .. } => val.clone(),
         other => Value::Error {
-            error: ShellError::UnsupportedInput(
-                format!(
-                    "Input's type is {}. This command only works with bytes.",
-                    other.get_type()
-                ),
+            error: ShellError::OnlySupportsThisInputType(
+                "binary".into(),
+                other.get_type().to_string(),
                 span,
+                // This line requires the Value::Error match above.
+                other.expect_span(),
             ),
         },
     }
@@ -159,7 +161,7 @@ fn remove_impl(input: &[u8], arg: &Arguments, span: Span) -> Value {
 
     // Note:
     // remove_all from start and end will generate the same result.
-    // so we'll put `remove_all` relative logic into else clouse.
+    // so we'll put `remove_all` relative logic into else clause.
     if arg.end && !remove_all {
         let (mut left, mut right) = (
             input.len() as isize - arg.pattern.len() as isize,
@@ -170,7 +172,7 @@ fn remove_impl(input: &[u8], arg: &Arguments, span: Span) -> Value {
             left -= 1;
             right -= 1;
         }
-        // append the remaining thing to result, this can be happeneed when
+        // append the remaining thing to result, this can be happening when
         // we have something to remove and remove_all is False.
         let mut remain = input[..left as usize].iter().copied().rev().collect();
         result.append(&mut remain);
@@ -191,7 +193,7 @@ fn remove_impl(input: &[u8], arg: &Arguments, span: Span) -> Value {
                 right += 1;
             }
         }
-        // append the remaing thing to result, this can happened when
+        // append the remaining thing to result, this can happened when
         // we have something to remove and remove_all is False.
         let mut remain = input[left..].to_vec();
         result.append(&mut remain);

crates/nu-command/src/bytes/replace.rs

@@ -61,7 +61,7 @@ impl Command for BytesReplace {
         let cell_paths = (!cell_paths.is_empty()).then_some(cell_paths);
         let find = call.req::<Spanned<Vec<u8>>>(engine_state, stack, 0)?;
         if find.item.is_empty() {
-            return Err(ShellError::UnsupportedInput(
+            return Err(ShellError::TypeMismatch(
                 "the pattern to find cannot be empty".to_string(),
                 find.span,
             ));
@@ -130,13 +130,15 @@ fn replace(val: &Value, args: &Arguments, span: Span) -> Value {
             val,
             span: val_span,
         } => replace_impl(val, args, *val_span),
+        // Propagate errors by explicitly matching them before the final case.
+        Value::Error { .. } => val.clone(),
         other => Value::Error {
-            error: ShellError::UnsupportedInput(
-                format!(
-                    "Input's type is {}. This command only works with bytes.",
-                    other.get_type()
-                ),
+            error: ShellError::OnlySupportsThisInputType(
+                "binary".into(),
+                other.get_type().to_string(),
                 span,
+                // This line requires the Value::Error match above.
+                other.expect_span(),
             ),
         },
     }

crates/nu-command/src/bytes/reverse.rs

@@ -81,13 +81,15 @@ fn reverse(val: &Value, _args: &CellPathOnlyArgs, span: Span) -> Value {
                 span: *val_span,
             }
         }
+        // Propagate errors by explicitly matching them before the final case.
+        Value::Error { .. } => val.clone(),
         other => Value::Error {
-            error: ShellError::UnsupportedInput(
-                format!(
-                    "Input's type is {}. This command only works with bytes.",
-                    other.get_type()
-                ),
+            error: ShellError::OnlySupportsThisInputType(
+                "binary".into(),
+                other.get_type().to_string(),
                 span,
+                // This line requires the Value::Error match above.
+                other.expect_span(),
             ),
         },
     }

crates/nu-command/src/bytes/starts_with.rs

@@ -74,17 +74,17 @@ impl Command for BytesStartsWith {
             Example {
                 description: "Checks if binary starts with `0x[1F FF AA]`",
                 example: "0x[1F FF AA AA] | bytes starts-with 0x[1F FF AA]",
-                result: Some(Value::boolean(true, Span::test_data())),
+                result: Some(Value::test_bool(true)),
             },
             Example {
                 description: "Checks if binary starts with `0x[1F]`",
                 example: "0x[1F FF AA AA] | bytes starts-with 0x[1F]",
-                result: Some(Value::boolean(true, Span::test_data())),
+                result: Some(Value::test_bool(true)),
             },
             Example {
                 description: "Checks if binary starts with `0x[1F]`",
                 example: "0x[1F FF AA AA] | bytes starts-with 0x[11]",
-                result: Some(Value::boolean(false, Span::test_data())),
+                result: Some(Value::test_bool(false)),
             },
         ]
     }
@@ -96,13 +96,15 @@ fn starts_with(val: &Value, args: &Arguments, span: Span) -> Value {
             val,
             span: val_span,
         } => Value::boolean(val.starts_with(&args.pattern), *val_span),
+        // Propagate errors by explicitly matching them before the final case.
+        Value::Error { .. } => val.clone(),
         other => Value::Error {
-            error: ShellError::UnsupportedInput(
-                format!(
-                    "Input's type is {}. This command only works with bytes.",
-                    other.get_type()
-                ),
+            error: ShellError::OnlySupportsThisInputType(
+                "binary".into(),
+                other.get_type().to_string(),
                 span,
+                // This line requires the Value::Error match above.
+                other.expect_span(),
             ),
         },
     }

crates/nu-command/src/charting/hashable_value.rs

@@ -78,13 +78,14 @@ impl HashableValue {
             Value::String { val, span } => Ok(HashableValue::String { val, span }),
             Value::Binary { val, span } => Ok(HashableValue::Binary { val, span }),
 
-            _ => {
-                let input_span = value.span().unwrap_or(span);
-                Err(ShellError::UnsupportedInput(
-                    format!("input value {value:?} is not hashable"),
-                    input_span,
-                ))
-            }
+            // Explicitly propagate errors instead of dropping them.
+            Value::Error { error } => Err(error),
+            _ => Err(ShellError::UnsupportedInput(
+                "input value is not hashable".into(),
+                format!("input type: {:?}", value.get_type()),
+                span,
+                value.expect_span(),
+            )),
         }
     }
 

crates/nu-command/src/charting/histogram.rs

@@ -98,12 +98,11 @@ impl Command for Histogram {
         let frequency_name_arg = call.opt::<Spanned<String>>(engine_state, stack, 1)?;
         let frequency_column_name = match frequency_name_arg {
             Some(inner) => {
-                let span = inner.span;
                 if ["value", "count", "quantile", "percentage"].contains(&inner.item.as_str()) {
-                    return Err(ShellError::UnsupportedInput(
+                    return Err(ShellError::TypeMismatch(
                         "frequency-column-name can't be 'value', 'count' or 'percentage'"
                             .to_string(),
-                        span,
+                        inner.span,
                     ));
                 }
                 inner.item
@@ -119,7 +118,7 @@ impl Command for Histogram {
                 "normalize" => PercentageCalcMethod::Normalize,
                 "relative" => PercentageCalcMethod::Relative,
                 _ => {
-                    return Err(ShellError::UnsupportedInput(
+                    return Err(ShellError::TypeMismatch(
                         "calc method can only be 'normalize' or 'relative'".to_string(),
                         inner.span,
                     ))
@@ -130,16 +129,15 @@ impl Command for Histogram {
         let span = call.head;
         let data_as_value = input.into_value(span);
         // `input` is not a list, here we can return an error.
-        match data_as_value.as_list() {
-            Ok(list_value) => run_histogram(
-                list_value.to_vec(),
+        run_histogram(
+            data_as_value.as_list()?.to_vec(),
             column_name,
             frequency_column_name,
             calc_method,
             span,
-            ),
-            Err(e) => Err(e),
-        }
+            // Note that as_list() filters out Value::Error here.
+            data_as_value.expect_span(),
+        )
     }
 }
 
@@ -149,6 +147,7 @@ fn run_histogram(
     freq_column: String,
     calc_method: PercentageCalcMethod,
     head_span: Span,
+    list_span: Span,
 ) -> Result<PipelineData, ShellError> {
     let mut inputs = vec![];
     // convert from inputs to hashable values.
@@ -157,14 +156,24 @@ fn run_histogram(
             // some invalid input scenario needs to handle:
             // Expect input is a list of hashable value, if one value is not hashable, throw out error.
             for v in values {
-                let current_span = v.span().unwrap_or(head_span);
+                match v {
+                    // Propagate existing errors.
+                    Value::Error { error } => return Err(error),
+                    _ => {
+                        let t = v.get_type();
+                        let span = v.expect_span();
                         inputs.push(HashableValue::from_value(v, head_span).map_err(|_| {
                         ShellError::UnsupportedInput(
-                        "--column-name is not provided, can only support a list of simple value."
-                            .to_string(),
-                        current_span,
+                            "Since --column-name was not provided, only lists of hashable values are supported.".to_string(),
+                            format!(
+                                "input type: {t:?}"
+                            ),
+                            head_span,
+                            span,
                         )
-                })?);
+                    })?)
+                    }
+                }
             }
         }
         Some(ref col) => {
@@ -186,14 +195,17 @@ fn run_histogram(
                             }
                         }
                     }
+                    // Propagate existing errors.
+                    Value::Error { error } => return Err(error),
                     _ => continue,
                 }
             }
 
             if inputs.is_empty() {
-                return Err(ShellError::UnsupportedInput(
-                    format!("expect input is table, and inputs doesn't contain any value which has {col_name} column"),
+                return Err(ShellError::CantFindColumn(
+                    col_name.clone(),
                     head_span,
+                    list_span,
                 ));
             }
         }

crates/nu-command/src/conversions/fmt.rs

@@ -44,14 +44,14 @@ impl Command for Fmt {
                     "upperhex".into(),
                 ],
                 vals: vec![
-                    Value::string("0b101010", Span::test_data()),
-                    Value::string("42", Span::test_data()),
-                    Value::string("42", Span::test_data()),
-                    Value::string("4.2e1", Span::test_data()),
-                    Value::string("0x2a", Span::test_data()),
-                    Value::string("0o52", Span::test_data()),
-                    Value::string("4.2E1", Span::test_data()),
-                    Value::string("0x2A", Span::test_data()),
+                    Value::test_string("0b101010"),
+                    Value::test_string("42"),
+                    Value::test_string("42"),
+                    Value::test_string("4.2e1"),
+                    Value::test_string("0x2a"),
+                    Value::test_string("0o52"),
+                    Value::test_string("4.2E1"),
+                    Value::test_string("0x2A"),
                 ],
                 span: Span::test_data(),
             }),
@@ -84,10 +84,15 @@ fn action(input: &Value, _args: &CellPathOnlyArgs, span: Span) -> Value {
     match input {
         Value::Int { val, .. } => fmt_it(*val, span),
         Value::Filesize { val, .. } => fmt_it(*val, span),
-        _ => Value::Error {
-            error: ShellError::UnsupportedInput(
-                format!("unsupported input type: {:?}", input.get_type()),
+        // Propagate errors by explicitly matching them before the final case.
+        Value::Error { .. } => input.clone(),
+        other => Value::Error {
+            error: ShellError::OnlySupportsThisInputType(
+                "integer or filesize".into(),
+                other.get_type().to_string(),
                 span,
+                // This line requires the Value::Error match above.
+                other.expect_span(),
             ),
         },
     }
@@ -98,31 +103,31 @@ fn fmt_it(num: i64, span: Span) -> Value {
     let mut vals = vec![];
 
     cols.push("binary".into());
-    vals.push(Value::string(format!("{:#b}", num), span));
+    vals.push(Value::string(format!("{num:#b}"), span));
 
     cols.push("debug".into());
-    vals.push(Value::string(format!("{:#?}", num), span));
+    vals.push(Value::string(format!("{num:#?}"), span));
 
     cols.push("display".into());
-    vals.push(Value::string(format!("{}", num), span));
+    vals.push(Value::string(format!("{num}"), span));
 
     cols.push("lowerexp".into());
-    vals.push(Value::string(format!("{:#e}", num), span));
+    vals.push(Value::string(format!("{num:#e}"), span));
 
     cols.push("lowerhex".into());
-    vals.push(Value::string(format!("{:#x}", num), span));
+    vals.push(Value::string(format!("{num:#x}"), span));
 
     cols.push("octal".into());
-    vals.push(Value::string(format!("{:#o}", num), span));
+    vals.push(Value::string(format!("{num:#o}"), span));
 
     // cols.push("pointer".into());
     // vals.push(Value::string(format!("{:#p}", &num), span));
 
     cols.push("upperexp".into());
-    vals.push(Value::string(format!("{:#E}", num), span));
+    vals.push(Value::string(format!("{num:#E}"), span));
 
     cols.push("upperhex".into());
-    vals.push(Value::string(format!("{:#X}", num), span));
+    vals.push(Value::string(format!("{num:#X}"), span));
 
     Value::Record { cols, vals, span }
 }

crates/nu-command/src/conversions/into/binary.rs

@@ -177,13 +177,24 @@ pub fn action(input: &Value, _args: &CellPathOnlyArgs, span: Span) -> Value {
             val: int_to_endian(i64::from(*val)),
             span,
         },
+        Value::Duration { val, .. } => Value::Binary {
+            val: int_to_endian(*val),
+            span,
+        },
         Value::Date { val, .. } => Value::Binary {
             val: val.format("%c").to_string().as_bytes().to_vec(),
             span,
         },
-
-        _ => Value::Error {
-            error: ShellError::UnsupportedInput("'into binary' for unsupported type".into(), span),
+        // Propagate errors by explicitly matching them before the final case.
+        Value::Error { .. } => input.clone(),
+        other => Value::Error {
+            error: ShellError::OnlySupportsThisInputType(
+                "integer, float, filesize, string, date, duration, binary or bool".into(),
+                other.get_type().to_string(),
+                span,
+                // This line requires the Value::Error match above.
+                other.expect_span(),
+            ),
         },
     }
 }

crates/nu-command/src/conversions/into/bool.rs

@@ -163,10 +163,15 @@ fn action(input: &Value, _args: &CellPathOnlyArgs, span: Span) -> Value {
             Ok(val) => Value::Bool { val, span },
             Err(error) => Value::Error { error },
         },
-        _ => Value::Error {
-            error: ShellError::UnsupportedInput(
-                "'into bool' does not support this input".into(),
+        // Propagate errors by explicitly matching them before the final case.
+        Value::Error { .. } => input.clone(),
+        other => Value::Error {
+            error: ShellError::OnlySupportsThisInputType(
+                "bool, integer, float or string".into(),
+                other.get_type().to_string(),
                 span,
+                // This line requires the Value::Error match above.
+                other.expect_span(),
             ),
         },
     }

crates/nu-command/src/conversions/into/command.rs

@@ -2,7 +2,7 @@ use nu_engine::get_full_help;
 use nu_protocol::{
     ast::Call,
     engine::{Command, EngineState, Stack},
-    Category, IntoPipelineData, PipelineData, Signature, Value,
+    Category, IntoPipelineData, PipelineData, Signature, Type, Value,
 };
 
 #[derive(Clone)]
@@ -14,13 +14,19 @@ impl Command for Into {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("into").category(Category::Conversions)
+        Signature::build("into")
+            .category(Category::Conversions)
+            .input_output_types(vec![(Type::Nothing, Type::String)])
     }
 
     fn usage(&self) -> &str {
         "Commands to convert data from one type to another."
     }
 
+    fn extra_usage(&self) -> &str {
+        "You must use one of the following subcommands. Using this command as-is will only produce this help message."
+    }
+
     fn run(
         &self,
         engine_state: &EngineState,
@@ -41,15 +47,3 @@ impl Command for Into {
         .into_pipeline_data())
     }
 }
-
-#[cfg(test)]
-mod test {
-    use super::*;
-
-    #[test]
-    fn test_examples() {
-        use crate::test_examples;
-
-        test_examples(Into {})
-    }
-}

crates/nu-command/src/conversions/into/datetime.rs

@@ -147,41 +147,19 @@ impl Command for SubCommand {
     }
 
     fn examples(&self) -> Vec<Example> {
-        let example_result_1 = |secs: i64, nsecs: u32| {
-            let dt = match Utc.timestamp_opt(secs, nsecs) {
-                LocalResult::Single(dt) => Some(dt),
-                _ => None,
-            };
-            match dt {
-                Some(dt) => Some(Value::Date {
+        let example_result_1 = |secs: i64, nsecs: u32| match Utc.timestamp_opt(secs, nsecs) {
+            LocalResult::Single(dt) => Some(Value::Date {
                 val: dt.into(),
                 span: Span::test_data(),
             }),
-                None => Some(Value::Error {
-                    error: ShellError::UnsupportedInput(
-                        "The given datetime representation is unsupported.".to_string(),
-                        Span::test_data(),
-                    ),
-                }),
-            }
+            _ => panic!("datetime: help example is invalid"),
         };
-        let example_result_2 = |millis: i64| {
-            let dt = match Utc.timestamp_millis_opt(millis) {
-                LocalResult::Single(dt) => Some(dt),
-                _ => None,
-            };
-            match dt {
-                Some(dt) => Some(Value::Date {
+        let example_result_2 = |millis: i64| match Utc.timestamp_millis_opt(millis) {
+            LocalResult::Single(dt) => Some(Value::Date {
                 val: dt.into(),
                 span: Span::test_data(),
             }),
-                None => Some(Value::Error {
-                    error: ShellError::UnsupportedInput(
-                        "The given datetime representation is unsupported.".to_string(),
-                        Span::test_data(),
-                    ),
-                }),
-            }
+            _ => panic!("datetime: help example is invalid"),
         };
         vec![
             Example {
@@ -213,7 +191,7 @@ impl Command for SubCommand {
             },
             Example {
                 description:
-                    "Convert timestamps like the sqlite history t",
+                    "Convert a millisecond-precise timestamp",
                 example: "1656165681720 | into datetime",
                 result: example_result_2(1656165681720)
             },
@@ -231,11 +209,16 @@ fn action(input: &Value, args: &Arguments, head: Span) -> Value {
     let timestamp = match input {
         Value::Int { val, .. } => Ok(*val),
         Value::String { val, .. } => val.parse::<i64>(),
+        // Propagate errors by explicitly matching them before the final case.
+        Value::Error { .. } => return input.clone(),
         other => {
             return Value::Error {
-                error: ShellError::UnsupportedInput(
-                    format!("Expected string or int, got {} instead", other.get_type()),
+                error: ShellError::OnlySupportsThisInputType(
+                    "string and integer".into(),
+                    other.get_type().to_string(),
                     head,
+                    // This line requires the Value::Error match above.
+                    other.expect_span(),
                 ),
             };
         }
@@ -248,113 +231,68 @@ fn action(input: &Value, args: &Arguments, head: Span) -> Value {
         if ts.abs() > TIMESTAMP_BOUND {
             return Value::Error {
                 error: ShellError::UnsupportedInput(
-                    "Given timestamp is out of range, it should between -8e+12 and 8e+12"
-                        .to_string(),
+                    "timestamp is out of range; it should between -8e+12 and 8e+12".to_string(),
+                    format!("timestamp is {ts:?}"),
+                    head,
+                    // Again, can safely unwrap this from here on
+                    input.expect_span(),
+                ),
+            };
+        }
+
+        macro_rules! match_datetime {
+            ($expr:expr) => {
+                match $expr {
+                    LocalResult::Single(dt) => Value::Date {
+                        val: dt.into(),
+                        span: head,
+                    },
+                    _ => {
+                        return Value::Error {
+                            error: ShellError::UnsupportedInput(
+                                "The given local datetime representation is invalid.".into(),
+                                format!("timestamp is {:?}", ts),
+                                head,
                                 head,
                             ),
                         };
                     }
+                }
+            };
+        }
 
         return match timezone {
             // default to UTC
             None => {
                 // be able to convert chrono::Utc::now()
-                let dt = match ts.to_string().len() {
-                    x if x > 13 => Utc.timestamp_nanos(ts).into(),
-                    x if x > 10 => match Utc.timestamp_millis_opt(ts) {
-                        LocalResult::Single(dt) => dt.into(),
-                        _ => {
-                            return Value::Error {
-                                // This error message is from chrono
-                                error: ShellError::UnsupportedInput(
-                                    "The given local datetime representation is invalid."
-                                        .to_string(),
-                                    head,
-                                ),
-                            };
-                        }
-                    },
-                    _ => match Utc.timestamp_opt(ts, 0) {
-                        LocalResult::Single(dt) => dt.into(),
-                        _ => {
-                            return Value::Error {
-                                error: ShellError::UnsupportedInput(
-                                    "The given local datetime representation is invalid."
-                                        .to_string(),
-                                    head,
-                                ),
-                            }
-                        }
-                    },
-                };
-
-                Value::Date {
-                    val: dt,
+                match ts.to_string().len() {
+                    x if x > 13 => Value::Date {
+                        val: Utc.timestamp_nanos(ts).into(),
                         span: head,
+                    },
+                    x if x > 10 => match_datetime!(Utc.timestamp_millis_opt(ts)),
+                    _ => match_datetime!(Utc.timestamp_opt(ts, 0)),
                 }
             }
             Some(Spanned { item, span }) => match item {
-                Zone::Utc => match Utc.timestamp_opt(ts, 0) {
-                    LocalResult::Single(val) => Value::Date {
-                        val: val.into(),
-                        span: head,
-                    },
-                    _ => Value::Error {
-                        error: ShellError::UnsupportedInput(
-                            "The given local datetime representation is invalid.".to_string(),
-                            *span,
-                        ),
-                    },
-                },
-                Zone::Local => match Local.timestamp_opt(ts, 0) {
-                    LocalResult::Single(val) => Value::Date {
-                        val: val.into(),
-                        span: head,
-                    },
-                    _ => Value::Error {
-                        error: ShellError::UnsupportedInput(
-                            "The given local datetime representation is invalid.".to_string(),
-                            *span,
-                        ),
-                    },
-                },
+                Zone::Utc => match_datetime!(Utc.timestamp_opt(ts, 0)),
+                Zone::Local => match_datetime!(Local.timestamp_opt(ts, 0)),
                 Zone::East(i) => match FixedOffset::east_opt((*i as i32) * HOUR) {
-                    Some(eastoffset) => match eastoffset.timestamp_opt(ts, 0) {
-                        LocalResult::Single(val) => Value::Date { val, span: head },
-                        _ => Value::Error {
-                            error: ShellError::UnsupportedInput(
-                                "The given local datetime representation is invalid.".to_string(),
-                                *span,
-                            ),
-                        },
-                    },
+                    Some(eastoffset) => match_datetime!(eastoffset.timestamp_opt(ts, 0)),
                     None => Value::Error {
-                        error: ShellError::UnsupportedInput(
-                            "The given local datetime representation is invalid.".to_string(),
-                            *span,
-                        ),
+                        error: ShellError::DatetimeParseError(*span),
                     },
                 },
                 Zone::West(i) => match FixedOffset::west_opt((*i as i32) * HOUR) {
-                    Some(westoffset) => match westoffset.timestamp_opt(ts, 0) {
-                        LocalResult::Single(val) => Value::Date { val, span: head },
-                        _ => Value::Error {
-                            error: ShellError::UnsupportedInput(
-                                "The given local datetime representation is invalid.".to_string(),
-                                *span,
-                            ),
-                        },
-                    },
+                    Some(westoffset) => match_datetime!(westoffset.timestamp_opt(ts, 0)),
                     None => Value::Error {
-                        error: ShellError::UnsupportedInput(
-                            "The given local datetime representation is invalid.".to_string(),
-                            *span,
-                        ),
+                        error: ShellError::DatetimeParseError(*span),
                     },
                 },
                 Zone::Error => Value::Error {
-                    error: ShellError::UnsupportedInput(
-                        "Cannot convert given timezone or offset to timestamp".to_string(),
+                    // This is an argument error, not an input error
+                    error: ShellError::TypeMismatch(
+                        "Invalid timezone or offset".to_string(),
                         *span,
                     ),
                 },
@@ -391,10 +329,15 @@ fn action(input: &Value, args: &Arguments, head: Span) -> Value {
                 },
             }
         }
+        // Propagate errors by explicitly matching them before the final case.
+        Value::Error { .. } => input.clone(),
         other => Value::Error {
-            error: ShellError::UnsupportedInput(
-                format!("Expected string, got {} instead", other.get_type()),
+            error: ShellError::OnlySupportsThisInputType(
+                "string".into(),
+                other.get_type().to_string(),
                 head,
+                // This line requires the Value::Error match above.
+                other.expect_span(),
             ),
         },
     }

crates/nu-command/src/conversions/into/decimal.rs

@@ -105,18 +105,17 @@ fn action(input: &Value, _args: &CellPathOnlyArgs, head: Span) -> Value {
             },
             span: *span,
         },
-        other => {
-            let span = other.span();
-            match span {
-                Ok(s) => {
-                    let got = format!("Expected a string, got {} instead", other.get_type());
-                    Value::Error {
-                        error: ShellError::UnsupportedInput(got, s),
-                    }
-                }
-                Err(e) => Value::Error { error: e },
-            }
-        }
+        // Propagate errors by explicitly matching them before the final case.
+        Value::Error { .. } => input.clone(),
+        other => Value::Error {
+            error: ShellError::OnlySupportsThisInputType(
+                "string, integer or bool".into(),
+                other.get_type().to_string(),
+                head,
+                // This line requires the Value::Error match above.
+                other.expect_span(),
+            ),
+        },
     }
 }
 

crates/nu-command/src/conversions/into/duration.rs

@@ -468,9 +468,11 @@ fn action(
                     }
                 } else {
                     Value::Error {
-                        error: ShellError::UnsupportedInput(
-                            "'into duration' does not support this string input".into(),
+                        error: ShellError::CantConvert(
+                            "string".into(),
+                            "duration".into(),
                             span,
+                            None,
                         ),
                     }
                 }
@@ -481,10 +483,15 @@ fn action(
                 }
             }
         }
-        _ => Value::Error {
-            error: ShellError::UnsupportedInput(
-                "'into duration' does not support this input".into(),
+        // Propagate errors by explicitly matching them before the final case.
+        Value::Error { .. } => input.clone(),
+        other => Value::Error {
+            error: ShellError::OnlySupportsThisInputType(
+                "string or duration".into(),
+                other.get_type().to_string(),
                 span,
+                // This line requires the Value::Error match above.
+                other.expect_span(),
             ),
         },
     }

crates/nu-command/src/conversions/into/filesize.rs

@@ -116,20 +116,18 @@ pub fn action(input: &Value, _args: &CellPathOnlyArgs, span: Span) -> Value {
                 val: 0,
                 span: value_span,
             },
-            _ => Value::Error {
-                error: ShellError::UnsupportedInput(
-                    "'into filesize' for unsupported type".into(),
+            other => Value::Error {
+                error: ShellError::OnlySupportsThisInputType(
+                    "string and integer".into(),
+                    other.get_type().to_string(),
+                    span,
                     value_span,
                 ),
             },
         }
     } else {
-        Value::Error {
-            error: ShellError::UnsupportedInput(
-                "'into filesize' for unsupported type".into(),
-                span,
-            ),
-        }
+        // Propagate existing errors
+        input.clone()
     }
 }
 fn int_from_string(a_string: &str, span: Span) -> Result<i64, ShellError> {

crates/nu-command/src/conversions/into/int.rs

@@ -70,7 +70,7 @@ impl Command for SubCommand {
         let radix: u32 = match radix {
             Some(Value::Int { val, span }) => {
                 if !(2..=36).contains(&val) {
-                    return Err(ShellError::UnsupportedInput(
+                    return Err(ShellError::TypeMismatch(
                         "Radix must lie in the range [2, 36]".to_string(),
                         span,
                     ));
@@ -113,7 +113,7 @@ impl Command for SubCommand {
             Example {
                 description: "Convert file size to integer",
                 example: "4KB | into int",
-                result: Some(Value::int(4000, Span::test_data())),
+                result: Some(Value::test_int(4000)),
             },
             Example {
                 description: "Convert bool to integer",
@@ -187,9 +187,11 @@ fn action(input: &Value, args: &Arguments, span: Span) -> Value {
                         Ok(v) => v,
                         _ => {
                             return Value::Error {
-                                error: ShellError::UnsupportedInput(
-                                    "Could not convert float to integer".to_string(),
+                                error: ShellError::CantConvert(
+                                    "float".to_string(),
+                                    "integer".to_string(),
                                     span,
+                                    None,
                                 ),
                             }
                         }
@@ -219,6 +221,7 @@ fn action(input: &Value, args: &Arguments, span: Span) -> Value {
             val: val.timestamp(),
             span,
         },
+        Value::Duration { val, .. } => Value::Int { val: *val, span },
         Value::Binary { val, span } => {
             use byteorder::{BigEndian, ByteOrder, LittleEndian};
 
@@ -240,10 +243,15 @@ fn action(input: &Value, args: &Arguments, span: Span) -> Value {
                 Value::int(BigEndian::read_i64(&val), *span)
             }
         }
-        _ => Value::Error {
-            error: ShellError::UnsupportedInput(
-                format!("'into int' for unsupported type '{}'", input.get_type()),
+        // Propagate errors by explicitly matching them before the final case.
+        Value::Error { .. } => input.clone(),
+        other => Value::Error {
+            error: ShellError::OnlySupportsThisInputType(
+                "integer, float, filesize, date, string, binary, duration or bool".into(),
+                other.get_type().to_string(),
                 span,
+                // This line requires the Value::Error match above.
+                other.expect_span(),
             ),
         },
     }
@@ -281,13 +289,18 @@ fn convert_int(input: &Value, head: Span, radix: u32) -> Value {
             }
             val.to_string()
         }
-        _ => {
+        // Propagate errors by explicitly matching them before the final case.
+        Value::Error { .. } => return input.clone(),
+        other => {
             return Value::Error {
-                error: ShellError::UnsupportedInput(
-                    "only strings or integers are supported".to_string(),
+                error: ShellError::OnlySupportsThisInputType(
+                    "string and integer".into(),
+                    other.get_type().to_string(),
                     head,
+                    // This line requires the Value::Error match above.
+                    other.expect_span(),
                 ),
-            }
+            };
         }
     };
     match i64::from_str_radix(i.trim(), radix) {
@@ -354,8 +367,7 @@ fn int_from_string(a_string: &str, span: Span) -> Result<i64, ShellError> {
                     "string".to_string(),
                     span,
                     Some(format!(
-                        r#"string "{}" does not represent a valid integer"#,
-                        trimmed
+                        r#"string "{trimmed}" does not represent a valid integer"#
                     )),
                 )),
             },

crates/nu-command/src/conversions/into/record.rs

@@ -183,12 +183,16 @@ fn into_record(
             Value::Record { cols, vals, span }
         }
         Value::Record { cols, vals, span } => Value::Record { cols, vals, span },
-        other => {
-            return Err(ShellError::UnsupportedInput(
-                "'into record' does not support this input".into(),
-                other.span().unwrap_or(call.head),
-            ))
-        }
+        Value::Error { .. } => input,
+        other => Value::Error {
+            error: ShellError::OnlySupportsThisInputType(
+                "string".into(),
+                other.get_type().to_string(),
+                call.head,
+                // This line requires the Value::Error match above.
+                other.expect_span(),
+            ),
+        },
     };
     Ok(res.into_pipeline_data())
 }

crates/nu-command/src/conversions/into/string.rs

@@ -79,22 +79,22 @@ impl Command for SubCommand {
             Example {
                 description: "convert integer to string and append three decimal places",
                 example: "5 | into string -d 3",
-                result: Some(Value::string("5.000", Span::test_data())),
+                result: Some(Value::test_string("5.000")),
             },
             Example {
                 description: "convert decimal to string and round to nearest integer",
                 example: "1.7 | into string -d 0",
-                result: Some(Value::string("2", Span::test_data())),
+                result: Some(Value::test_string("2")),
             },
             Example {
                 description: "convert decimal to string",
                 example: "1.7 | into string -d 1",
-                result: Some(Value::string("1.7", Span::test_data())),
+                result: Some(Value::test_string("1.7")),
             },
             Example {
                 description: "convert decimal to string and limit to 2 decimals",
                 example: "1.734 | into string -d 2",
-                result: Some(Value::string("1.73", Span::test_data())),
+                result: Some(Value::test_string("1.73")),
             },
             Example {
                 description: "try to convert decimal to string and provide negative decimal points",
@@ -111,17 +111,17 @@ impl Command for SubCommand {
             Example {
                 description: "convert decimal to string",
                 example: "4.3 | into string",
-                result: Some(Value::string("4.3", Span::test_data())),
+                result: Some(Value::test_string("4.3")),
             },
             Example {
                 description: "convert string to string",
                 example: "'1234' | into string",
-                result: Some(Value::string("1234", Span::test_data())),
+                result: Some(Value::test_string("1234")),
             },
             Example {
                 description: "convert boolean to string",
                 example: "true | into string",
-                result: Some(Value::string("true", Span::test_data())),
+                result: Some(Value::test_string("true")),
             },
             // TODO: This should work but does not; see https://github.com/nushell/nushell/issues/7032
             // Example {
@@ -154,7 +154,7 @@ fn string_helper(
     let decimals_value: Option<i64> = call.get_flag(engine_state, stack, "decimals")?;
     if let Some(decimal_val) = decimals_value {
         if decimals && decimal_val.is_negative() {
-            return Err(ShellError::UnsupportedInput(
+            return Err(ShellError::TypeMismatch(
                 "Cannot accept negative integers for decimals arguments".to_string(),
                 head,
             ));
@@ -206,7 +206,7 @@ fn action(input: &Value, args: &Arguments, span: Span) -> Value {
             if decimals {
                 let decimal_value = digits.unwrap_or(2) as usize;
                 Value::String {
-                    val: format!("{:.*}", decimal_value, val),
+                    val: format!("{val:.decimal_value$}"),
                     span,
                 }
             } else {
@@ -234,12 +234,7 @@ fn action(input: &Value, args: &Arguments, span: Span) -> Value {
             span,
         },
         Value::Error { error } => Value::String {
-            val: {
-                match into_code(error) {
-                    Some(code) => code,
-                    None => "".to_string(),
-                }
-            },
+            val: into_code(error).unwrap_or_default(),
             span,
         },
         Value::Nothing { .. } => Value::String {
@@ -251,9 +246,11 @@ fn action(input: &Value, args: &Arguments, span: Span) -> Value {
             vals: _,
             span: _,
         } => Value::Error {
-            error: ShellError::UnsupportedInput(
-                "Cannot convert Record into string".to_string(),
+            error: ShellError::CantConvert(
+                "record".into(),
+                "string".into(),
                 span,
+                Some("try using the `to nuon` command".into()),
             ),
         },
         Value::Binary { .. } => Value::Error {

crates/nu-command/src/core_commands/ast.rs

@@ -41,7 +41,7 @@ impl Command for Ast {
         let mut working_set = StateWorkingSet::new(engine_state);
 
         let (output, err) = parse(&mut working_set, None, pipeline.item.as_bytes(), false, &[]);
-        eprintln!("output: {:#?}\nerror: {:#?}", output, err);
+        eprintln!("output: {output:#?}\nerror: {err:#?}");
 
         Ok(PipelineData::empty())
     }

crates/nu-command/src/core_commands/const_.rs

@@ -0,0 +1,104 @@
+use nu_protocol::ast::Call;
+use nu_protocol::engine::{Command, EngineState, Stack};
+use nu_protocol::{Category, Example, PipelineData, ShellError, Signature, SyntaxShape, Type};
+
+#[derive(Clone)]
+pub struct Const;
+
+impl Command for Const {
+    fn name(&self) -> &str {
+        "const"
+    }
+
+    fn usage(&self) -> &str {
+        "Create a parse-time constant."
+    }
+
+    fn signature(&self) -> nu_protocol::Signature {
+        Signature::build("const")
+            .input_output_types(vec![(Type::Nothing, Type::Nothing)])
+            .allow_variants_without_examples(true)
+            .required("const_name", SyntaxShape::VarWithOptType, "constant name")
+            .required(
+                "initial_value",
+                SyntaxShape::Keyword(b"=".to_vec(), Box::new(SyntaxShape::Expression)),
+                "equals sign followed by constant value",
+            )
+            .category(Category::Core)
+    }
+
+    fn extra_usage(&self) -> &str {
+        r#"This command is a parser keyword. For details, check:
+  https://www.nushell.sh/book/thinking_in_nu.html"#
+    }
+
+    fn is_parser_keyword(&self) -> bool {
+        true
+    }
+
+    fn search_terms(&self) -> Vec<&str> {
+        vec!["set", "let"]
+    }
+
+    fn run(
+        &self,
+        engine_state: &EngineState,
+        stack: &mut Stack,
+        call: &Call,
+        _input: PipelineData,
+    ) -> Result<nu_protocol::PipelineData, nu_protocol::ShellError> {
+        let var_id = call
+            .positional_nth(0)
+            .expect("checked through parser")
+            .as_var()
+            .expect("internal error: missing variable");
+
+        if let Some(constval) = engine_state.find_constant(var_id, &[]) {
+            // Instead of creating a second copy of the value in the stack, we could change
+            // stack.get_var() to check engine_state.find_constant().
+            stack.add_var(var_id, constval.clone());
+
+            Ok(PipelineData::empty())
+        } else {
+            Err(ShellError::NushellFailedSpanned(
+                "Missing Constant".to_string(),
+                "constant not added by the parser".to_string(),
+                call.head,
+            ))
+        }
+    }
+
+    fn examples(&self) -> Vec<Example> {
+        vec![
+            Example {
+                description: "Create a new parse-time constant.",
+                example: "const x = 10",
+                result: None,
+            },
+            Example {
+                description: "Create a composite constant value",
+                example: "const x = { a: 10, b: 20 }",
+                result: None,
+            },
+        ]
+    }
+}
+
+#[cfg(test)]
+mod test {
+    use nu_protocol::engine::CommandType;
+
+    use super::*;
+
+    #[test]
+    fn test_examples() {
+        use crate::test_examples;
+
+        test_examples(Const {})
+    }
+
+    #[test]
+    fn test_command_type() {
+        assert!(matches!(Const.command_type(), CommandType::Keyword));
+    }
+}

crates/nu-command/src/core_commands/debug.rs

@@ -39,6 +39,8 @@ impl Command for Debug {
         let config = engine_state.get_config().clone();
         let raw = call.has_flag("raw");
 
+        // Should PipelineData::Empty result in an error here?
+
         input.map(
             move |x| {
                 if raw {

crates/nu-command/src/core_commands/def_env.rs

@@ -1,6 +1,6 @@
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{Category, Example, PipelineData, Signature, Span, SyntaxShape, Type, Value};
+use nu_protocol::{Category, Example, PipelineData, Signature, SyntaxShape, Type, Value};
 
 #[derive(Clone)]
 pub struct DefEnv;
@@ -72,7 +72,7 @@ def-env cd_with_fallback [arg = ""] {
         vec![Example {
             description: "Set environment variable by call a custom command",
             example: r#"def-env foo [] { let-env BAR = "BAZ" }; foo; $env.BAR"#,
-            result: Some(Value::string("BAZ", Span::test_data())),
+            result: Some(Value::test_string("BAZ")),
         }]
     }
 }

crates/nu-command/src/core_commands/describe.rs

@@ -19,6 +19,11 @@ impl Command for Describe {
     fn signature(&self) -> Signature {
         Signature::build("describe")
             .input_output_types(vec![(Type::Any, Type::String)])
+            .switch(
+                "no-collect",
+                "do not collect streams of structured data",
+                Some('n'),
+            )
             .category(Category::Core)
     }
 
@@ -30,32 +35,58 @@ impl Command for Describe {
         input: PipelineData,
     ) -> Result<PipelineData, ShellError> {
         let head = call.head;
-        if matches!(input, PipelineData::ExternalStream { .. }) {
-            Ok(PipelineData::Value(
-                Value::string("raw input", call.head),
-                None,
-            ))
+
+        let no_collect: bool = call.has_flag("no-collect");
+
+        let description = match input {
+            PipelineData::ExternalStream { .. } => "raw input".into(),
+            PipelineData::ListStream(_, _) => {
+                if no_collect {
+                    "stream".into()
                 } else {
-            let value = input.into_value(call.head);
-            let description = match value {
+                    let value = input.into_value(head);
+                    let base_description = match value {
                         Value::CustomValue { val, .. } => val.value_string(),
                         _ => value.get_type().to_string(),
                     };
 
+                    format!("{base_description} (stream)")
+                }
+            }
+            _ => {
+                let value = input.into_value(head);
+                match value {
+                    Value::CustomValue { val, .. } => val.value_string(),
+                    _ => value.get_type().to_string(),
+                }
+            }
+        };
+
         Ok(Value::String {
             val: description,
             span: head,
         }
         .into_pipeline_data())
     }
-    }
 
     fn examples(&self) -> Vec<Example> {
-        vec![Example {
+        vec![
+            Example {
                 description: "Describe the type of a string",
                 example: "'hello' | describe",
                 result: Some(Value::test_string("string")),
-        }]
+            },
+            Example {
+                description: "Describe a stream of data, collecting it first",
+                example: "[1 2 3] | each {|i| $i} | describe",
+                result: Some(Value::test_string("list<int> (stream)")),
+            },
+            Example {
+                description: "Describe the input but do not collect streams",
+                example: "[1 2 3] | each {|i| $i} | describe --no-collect",
+                result: Some(Value::test_string("stream")),
+            },
+        ]
     }
 
     fn search_terms(&self) -> Vec<&str> {

crates/nu-command/src/core_commands/do_.rs

@@ -1,8 +1,11 @@
+use std::thread;
+
 use nu_engine::{eval_block_with_early_return, CallExt};
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Closure, Command, EngineState, Stack};
 use nu_protocol::{
-    Category, Example, ListStream, PipelineData, ShellError, Signature, SyntaxShape, Type, Value,
+    Category, Example, ListStream, PipelineData, RawStream, ShellError, Signature, SyntaxShape,
+    Type, Value,
 };
 
 #[derive(Clone)]
@@ -106,7 +109,7 @@ impl Command for Do {
             block,
             input,
             call.redirect_stdout,
-            capture_errors || ignore_shell_errors || ignore_program_errors,
+            call.redirect_stdout,
         );
 
         match result {
@@ -118,6 +121,58 @@ impl Command for Do {
                 metadata,
                 trim_end_newline,
             }) if capture_errors => {
+                // Use a thread to receive stdout message.
+                // Or we may get a deadlock if child process sends out too much bytes to stderr.
+                //
+                // For example: in normal linux system, stderr pipe's limit is 65535 bytes.
+                // if child process sends out 65536 bytes, the process will be hanged because no consumer
+                // consumes the first 65535 bytes
+                // So we need a thread to receive stdout message, then the current thread can continue to consume
+                // stderr messages.
+                let stdout_handler = stdout.map(|stdout_stream| {
+                    thread::Builder::new()
+                        .name("stderr redirector".to_string())
+                        .spawn(move || {
+                            let ctrlc = stdout_stream.ctrlc.clone();
+                            let span = stdout_stream.span;
+                            RawStream::new(
+                                Box::new(
+                                    vec![stdout_stream.into_bytes().map(|s| s.item)].into_iter(),
+                                ),
+                                ctrlc,
+                                span,
+                                None,
+                            )
+                        })
+                        .expect("Failed to create thread")
+                });
+
+                // Intercept stderr so we can return it in the error if the exit code is non-zero.
+                // The threading issues mentioned above dictate why we also need to intercept stdout.
+                let mut stderr_ctrlc = None;
+                let stderr_msg = match stderr {
+                    None => "".to_string(),
+                    Some(stderr_stream) => {
+                        stderr_ctrlc = stderr_stream.ctrlc.clone();
+                        stderr_stream.into_string().map(|s| s.item)?
+                    }
+                };
+
+                let stdout = if let Some(handle) = stdout_handler {
+                    match handle.join() {
+                        Err(err) => {
+                            return Err(ShellError::ExternalCommand(
+                                "Fail to receive external commands stdout message".to_string(),
+                                format!("{err:?}"),
+                                span,
+                            ));
+                        }
+                        Ok(res) => Some(res),
+                    }
+                } else {
+                    None
+                };
+
                 let mut exit_code_ctrlc = None;
                 let exit_code: Vec<Value> = match exit_code {
                     None => vec![],
@@ -128,11 +183,6 @@ impl Command for Do {
                 };
                 if let Some(Value::Int { val: code, .. }) = exit_code.last() {
                     if *code != 0 {
-                        let stderr_msg = match stderr {
-                            None => "".to_string(),
-                            Some(stderr_stream) => stderr_stream.into_string().map(|s| s.item)?,
-                        };
-
                         return Err(ShellError::ExternalCommand(
                             "External command failed".to_string(),
                             stderr_msg,
@@ -143,7 +193,12 @@ impl Command for Do {
 
                 Ok(PipelineData::ExternalStream {
                     stdout,
-                    stderr,
+                    stderr: Some(RawStream::new(
+                        Box::new(vec![Ok(stderr_msg.into_bytes())].into_iter()),
+                        stderr_ctrlc,
+                        span,
+                        None,
+                    )),
                     exit_code: Some(ListStream::from_stream(
                         exit_code.into_iter(),
                         exit_code_ctrlc,
@@ -168,10 +223,9 @@ impl Command for Do {
                 metadata,
                 trim_end_newline,
             }),
-            Ok(PipelineData::Value(Value::Error { .. }, ..)) if ignore_shell_errors => {
+            Ok(PipelineData::Value(Value::Error { .. }, ..)) | Err(_) if ignore_shell_errors => {
                 Ok(PipelineData::empty())
             }
-            Err(_) if ignore_shell_errors => Ok(PipelineData::empty()),
             r => r,
         }
     }

crates/nu-command/src/core_commands/error_make.rs

@@ -2,7 +2,7 @@ use nu_engine::CallExt;
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
 use nu_protocol::{
-    Category, Example, PipelineData, ShellError, Signature, Span, SyntaxShape, Value,
+    Category, Example, PipelineData, ShellError, Signature, Span, SyntaxShape, Type, Value,
 };
 
 #[derive(Clone)]
@@ -15,6 +15,7 @@ impl Command for ErrorMake {
 
     fn signature(&self) -> Signature {
         Signature::build("error make")
+            .input_output_types(vec![(Type::Nothing, Type::Error)])
             .required("error_struct", SyntaxShape::Record, "the error to create")
             .switch(
                 "unspanned",

crates/nu-command/src/core_commands/export.rs

@@ -2,7 +2,7 @@ use nu_engine::get_full_help;
 use nu_protocol::{
     ast::Call,
     engine::{Command, EngineState, Stack},
-    Category, Example, IntoPipelineData, PipelineData, Signature, Span, Type, Value,
+    Category, Example, IntoPipelineData, PipelineData, Signature, Type, Value,
 };
 
 #[derive(Clone)]
@@ -56,7 +56,7 @@ impl Command for ExportCommand {
         vec![Example {
             description: "Export a definition from a module",
             example: r#"module utils { export def my-command [] { "hello" } }; use utils my-command; my-command"#,
-            result: Some(Value::string("hello", Span::test_data())),
+            result: Some(Value::test_string("hello")),
         }]
     }
 

crates/nu-command/src/core_commands/export_def.rs

@@ -1,6 +1,6 @@
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{Category, Example, PipelineData, Signature, Span, SyntaxShape, Type, Value};
+use nu_protocol::{Category, Example, PipelineData, Signature, SyntaxShape, Type, Value};
 
 #[derive(Clone)]
 pub struct ExportDef;
@@ -46,7 +46,7 @@ impl Command for ExportDef {
         vec![Example {
             description: "Define a custom command in a module and call it",
             example: r#"module spam { export def foo [] { "foo" } }; use spam foo; foo"#,
-            result: Some(Value::string("foo", Span::test_data())),
+            result: Some(Value::test_string("foo")),
         }]
     }
 

crates/nu-command/src/core_commands/export_def_env.rs

@@ -1,6 +1,6 @@
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{Category, Example, PipelineData, Signature, Span, SyntaxShape, Type, Value};
+use nu_protocol::{Category, Example, PipelineData, Signature, SyntaxShape, Type, Value};
 
 #[derive(Clone)]
 pub struct ExportDefEnv;
@@ -72,7 +72,7 @@ export def-env cd_with_fallback [arg = ""] {
         vec![Example {
             description: "Define a custom command that participates in the environment in a module and call it",
             example: r#"module foo { export def-env bar [] { let-env FOO_BAR = "BAZ" } }; use foo bar; bar; $env.FOO_BAR"#,
-            result: Some(Value::string("BAZ", Span::test_data())),
+            result: Some(Value::test_string("BAZ")),
         }]
     }
 

crates/nu-command/src/core_commands/export_use.rs

@@ -1,6 +1,6 @@
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{Category, Example, PipelineData, Signature, Span, SyntaxShape, Type, Value};
+use nu_protocol::{Category, Example, PipelineData, Signature, SyntaxShape, Type, Value};
 
 #[derive(Clone)]
 pub struct ExportUse;
@@ -17,7 +17,12 @@ impl Command for ExportUse {
     fn signature(&self) -> nu_protocol::Signature {
         Signature::build("export use")
             .input_output_types(vec![(Type::Nothing, Type::Nothing)])
-            .required("pattern", SyntaxShape::ImportPattern, "import pattern")
+            .required("module", SyntaxShape::String, "Module or module file")
+            .optional(
+                "members",
+                SyntaxShape::Any,
+                "Which members of the module to import",
+            )
             .category(Category::Core)
     }
 
@@ -48,7 +53,7 @@ impl Command for ExportUse {
     use eggs foo
     foo
             "#,
-            result: Some(Value::string("foo", Span::test_data())),
+            result: Some(Value::test_string("foo")),
         }]
     }
 

crates/nu-command/src/core_commands/for_.rs

@@ -2,7 +2,7 @@ use nu_engine::{eval_block, eval_expression, CallExt};
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Block, Command, EngineState, Stack};
 use nu_protocol::{
-    Category, Example, ListStream, PipelineData, ShellError, Signature, SyntaxShape, Value,
+    Category, Example, ListStream, PipelineData, ShellError, Signature, SyntaxShape, Type, Value,
 };
 
 #[derive(Clone)]
@@ -19,6 +19,8 @@ impl Command for For {
 
     fn signature(&self) -> nu_protocol::Signature {
         Signature::build("for")
+            .input_output_types(vec![(Type::Nothing, Type::Nothing)])
+            .allow_variants_without_examples(true)
             .required(
                 "var_name",
                 SyntaxShape::VarWithOptType,

crates/nu-command/src/core_commands/help.rs

@@ -1,17 +1,18 @@
+use crate::help_aliases::help_aliases;
+use crate::help_commands::help_commands;
+use crate::help_modules::help_modules;
 use fancy_regex::Regex;
 use nu_ansi_term::{
     Color::{Red, White},
     Style,
 };
-use nu_color_config::StyleComputer;
-use nu_engine::{get_full_help, CallExt};
+use nu_engine::CallExt;
 use nu_protocol::{
     ast::Call,
     engine::{Command, EngineState, Stack},
-    span, Category, Example, IntoInterruptiblePipelineData, IntoPipelineData, PipelineData,
-    ShellError, Signature, Span, Spanned, SyntaxShape, Type, Value,
+    span, Category, Example, IntoPipelineData, PipelineData, ShellError, Signature, Span, Spanned,
+    SyntaxShape, Type, Value,
 };
-use std::borrow::Borrow;
 #[derive(Clone)]
 pub struct Help;
 
@@ -26,7 +27,7 @@ impl Command for Help {
             .rest(
                 "rest",
                 SyntaxShape::String,
-                "the name of command to get help on",
+                "the name of command, alias or module to get help on",
             )
             .named(
                 "find",
@@ -38,7 +39,11 @@ impl Command for Help {
     }
 
     fn usage(&self) -> &str {
-        "Display help information about commands."
+        "Display help information about different parts of Nushell."
+    }
+
+    fn extra_usage(&self) -> &str {
+        r#"`help word` searches for "word" in commands, aliases and modules, in that order."#
     }
 
     fn run(
@@ -47,270 +52,19 @@ impl Command for Help {
         stack: &mut Stack,
         call: &Call,
         _input: PipelineData,
-    ) -> Result<PipelineData, ShellError> {
-        help(engine_state, stack, call)
-    }
-
-    fn examples(&self) -> Vec<Example> {
-        vec![
-            Example {
-                description: "show all commands and sub-commands",
-                example: "help commands",
-                result: None,
-            },
-            Example {
-                description: "show help for single command",
-                example: "help match",
-                result: None,
-            },
-            Example {
-                description: "show help for single sub-command",
-                example: "help str lpad",
-                result: None,
-            },
-            Example {
-                description: "search for string in command names, usage and search terms",
-                example: "help --find char",
-                result: None,
-            },
-        ]
-    }
-}
-
-fn help(
-    engine_state: &EngineState,
-    stack: &mut Stack,
-    call: &Call,
     ) -> Result<PipelineData, ShellError> {
         let head = call.head;
         let find: Option<Spanned<String>> = call.get_flag(engine_state, stack, "find")?;
         let rest: Vec<Spanned<String>> = call.rest(engine_state, stack, 0)?;
-    let commands = engine_state.get_decl_ids_sorted(false);
 
-    // 🚩The following two-lines are copied from filters/find.rs:
-    let style_computer = StyleComputer::from_config(engine_state, stack);
-    // Currently, search results all use the same style.
-    // Also note that this sample string is passed into user-written code (the closure that may or may not be
-    // defined for "string").
-    let string_style = style_computer.compute("string", &Value::string("search result", head));
-
-    if let Some(f) = find {
-        let org_search_string = f.item.clone();
-        let search_string = f.item.to_lowercase();
-        let mut found_cmds_vec = Vec::new();
-
-        for decl_id in commands {
-            let mut cols = vec![];
-            let mut vals = vec![];
-            let decl = engine_state.get_decl(decl_id);
-            let sig = decl.signature().update_from_command(decl.borrow());
-            let signatures = sig.to_string();
-            let key = sig.name;
-            let usage = sig.usage;
-            let search_terms = sig.search_terms;
-
-            let matches_term = if !search_terms.is_empty() {
-                search_terms
-                    .iter()
-                    .any(|term| term.to_lowercase().contains(&search_string))
-            } else {
-                false
-            };
-
-            let key_match = key.to_lowercase().contains(&search_string);
-            let usage_match = usage.to_lowercase().contains(&search_string);
-            if key_match || usage_match || matches_term {
-                cols.push("name".into());
-                vals.push(Value::String {
-                    val: if key_match {
-                        highlight_search_string(&key, &org_search_string, &string_style)?
-                    } else {
-                        key
-                    },
-                    span: head,
-                });
-
-                cols.push("category".into());
-                vals.push(Value::string(sig.category.to_string(), head));
-
-                cols.push("command_type".into());
-                vals.push(Value::String {
-                    val: format!("{:?}", decl.command_type()).to_lowercase(),
-                    span: head,
-                });
-
-                cols.push("usage".into());
-                vals.push(Value::String {
-                    val: if usage_match {
-                        highlight_search_string(&usage, &org_search_string, &string_style)?
-                    } else {
-                        usage
-                    },
-                    span: head,
-                });
-
-                cols.push("signatures".into());
-                vals.push(Value::String {
-                    val: if decl.is_parser_keyword() {
-                        "".to_string()
-                    } else {
-                        signatures
-                    },
-                    span: head,
-                });
-
-                cols.push("search_terms".into());
-                vals.push(if search_terms.is_empty() {
-                    Value::nothing(head)
-                } else {
-                    Value::String {
-                        val: if matches_term {
-                            search_terms
-                                .iter()
-                                .map(|term| {
-                                    if term.to_lowercase().contains(&search_string) {
-                                        match highlight_search_string(
-                                            term,
-                                            &org_search_string,
-                                            &string_style,
-                                        ) {
-                                            Ok(s) => s,
-                                            Err(_) => {
-                                                string_style.paint(term.to_string()).to_string()
-                                            }
-                                        }
-                                    } else {
-                                        string_style.paint(term.to_string()).to_string()
-                                    }
-                                })
-                                .collect::<Vec<_>>()
-                                .join(", ")
-                        } else {
-                            search_terms.join(", ")
-                        },
-                        span: head,
-                    }
-                });
-
-                found_cmds_vec.push(Value::Record {
-                    cols,
-                    vals,
-                    span: head,
-                });
-            }
-        }
-
-        return Ok(found_cmds_vec
-            .into_iter()
-            .into_pipeline_data(engine_state.ctrlc.clone()));
-    }
-
-    if !rest.is_empty() {
-        let mut found_cmds_vec = Vec::new();
-
-        if rest[0].item == "commands" {
-            for decl_id in commands {
-                let mut cols = vec![];
-                let mut vals = vec![];
-
-                let decl = engine_state.get_decl(decl_id);
-                let sig = decl.signature().update_from_command(decl.borrow());
-
-                let signatures = sig.to_string();
-                let key = sig.name;
-                let usage = sig.usage;
-                let search_terms = sig.search_terms;
-
-                cols.push("name".into());
-                vals.push(Value::String {
-                    val: key,
-                    span: head,
-                });
-
-                cols.push("category".into());
-                vals.push(Value::string(sig.category.to_string(), head));
-
-                cols.push("command_type".into());
-                vals.push(Value::String {
-                    val: format!("{:?}", decl.command_type()).to_lowercase(),
-                    span: head,
-                });
-
-                cols.push("usage".into());
-                vals.push(Value::String {
-                    val: usage,
-                    span: head,
-                });
-
-                cols.push("signatures".into());
-                vals.push(Value::String {
-                    val: if decl.is_parser_keyword() {
-                        "".to_string()
-                    } else {
-                        signatures
-                    },
-                    span: head,
-                });
-
-                cols.push("search_terms".into());
-                vals.push(if search_terms.is_empty() {
-                    Value::nothing(head)
-                } else {
-                    Value::String {
-                        val: search_terms.join(", "),
-                        span: head,
-                    }
-                });
-
-                found_cmds_vec.push(Value::Record {
-                    cols,
-                    vals,
-                    span: head,
-                });
-            }
-
-            Ok(found_cmds_vec
-                .into_iter()
-                .into_pipeline_data(engine_state.ctrlc.clone()))
-        } else {
-            let mut name = String::new();
-
-            for r in &rest {
-                if !name.is_empty() {
-                    name.push(' ');
-                }
-                name.push_str(&r.item);
-            }
-
-            let output = engine_state
-                .get_signatures_with_examples(false)
-                .iter()
-                .filter(|(signature, _, _, _, _)| signature.name == name)
-                .map(|(signature, examples, _, _, is_parser_keyword)| {
-                    get_full_help(signature, examples, engine_state, stack, *is_parser_keyword)
-                })
-                .collect::<Vec<String>>();
-
-            if !output.is_empty() {
-                Ok(Value::String {
-                    val: output.join("======================\n\n"),
-                    span: call.head,
-                }
-                .into_pipeline_data())
-            } else {
-                Err(ShellError::CommandNotFound(span(&[
-                    rest[0].span,
-                    rest[rest.len() - 1].span,
-                ])))
-            }
-        }
-    } else {
+        if rest.is_empty() && find.is_none() {
             let msg = r#"Welcome to Nushell.
 
 Here are some tips to help you get started.
+  * help -h or help help - show available `help` subcommands and examples
   * help commands - list all available commands
-  * help <command name> - display help about a particular command
-  * help --find <text to search> - search through all of help
+  * help <name> - display help about a particular command, alias, or module
+  * help --find <text to search> - search through all help commands table
 
 Nushell works on the idea of a "pipeline". Pipelines are commands connected with the '|' character.
 Each stage in the pipeline works together to load, parse, and display information to you.
@@ -329,8 +83,111 @@ Get the processes on your system actively using CPU:
 You can also learn more at https://www.nushell.sh/book/"#;
 
             Ok(Value::string(msg, head).into_pipeline_data())
+        } else if find.is_some() {
+            help_commands(engine_state, stack, call)
+        } else {
+            let result = help_commands(engine_state, stack, call);
+
+            let result = if let Err(ShellError::CommandNotFound(_)) = result {
+                help_aliases(engine_state, stack, call)
+            } else {
+                result
+            };
+
+            let result = if let Err(ShellError::AliasNotFound(_)) = result {
+                help_modules(engine_state, stack, call)
+            } else {
+                result
+            };
+
+            if let Err(ShellError::ModuleNotFoundAtRuntime(_, _)) = result {
+                let rest_spans: Vec<Span> = rest.iter().map(|arg| arg.span).collect();
+                Err(ShellError::NotFound(span(&rest_spans)))
+            } else {
+                result
             }
         }
+    }
+
+    fn examples(&self) -> Vec<Example> {
+        vec![
+            Example {
+                description: "show help for single command, alias, or module",
+                example: "help match",
+                result: None,
+            },
+            Example {
+                description: "show help for single sub-command, alias, or module",
+                example: "help str lpad",
+                result: None,
+            },
+            Example {
+                description: "search for string in command names, usage and search terms",
+                example: "help --find char",
+                result: None,
+            },
+        ]
+    }
+}
+
+pub fn highlight_search_in_table(
+    table: Vec<Value>, // list of records
+    search_string: &str,
+    searched_cols: &[&str],
+    string_style: &Style,
+) -> Result<Vec<Value>, ShellError> {
+    let orig_search_string = search_string;
+    let search_string = search_string.to_lowercase();
+    let mut matches = vec![];
+
+    for record in table {
+        let (cols, mut vals, record_span) = if let Value::Record { cols, vals, span } = record {
+            (cols, vals, span)
+        } else {
+            return Err(ShellError::NushellFailedSpanned(
+                "Expected record".to_string(),
+                format!("got {}", record.get_type()),
+                record.span()?,
+            ));
+        };
+
+        let has_match = cols.iter().zip(vals.iter_mut()).fold(
+            Ok(false),
+            |acc: Result<bool, ShellError>, (col, val)| {
+                if searched_cols.contains(&col.as_str()) {
+                    if let Value::String { val: s, span } = val {
+                        if s.to_lowercase().contains(&search_string) {
+                            *val = Value::String {
+                                val: highlight_search_string(s, orig_search_string, string_style)?,
+                                span: *span,
+                            };
+                            Ok(true)
+                        } else {
+                            // column does not contain the searched string
+                            acc
+                        }
+                    } else {
+                        // ignore non-string values
+                        acc
+                    }
+                } else {
+                    // don't search this column
+                    acc
+                }
+            },
+        )?;
+
+        if has_match {
+            matches.push(Value::Record {
+                cols,
+                vals,
+                span: record_span,
+            });
+        }
+    }
+
+    Ok(matches)
+}
 
 // Highlight the search string using ANSI escape sequences and regular expressions.
 pub fn highlight_search_string(
@@ -338,7 +195,7 @@ pub fn highlight_search_string(
     needle: &str,
     string_style: &Style,
 ) -> Result<String, ShellError> {
-    let regex_string = format!("(?i){}", needle);
+    let regex_string = format!("(?i){needle}");
     let regex = match Regex::new(&regex_string) {
         Ok(regex) => regex,
         Err(err) => {

crates/nu-command/src/core_commands/help_aliases.rs

@@ -0,0 +1,181 @@
+use crate::help::highlight_search_in_table;
+use nu_color_config::StyleComputer;
+use nu_engine::{scope::ScopeData, CallExt};
+use nu_protocol::{
+    ast::Call,
+    engine::{Command, EngineState, Stack},
+    span, Category, Example, IntoInterruptiblePipelineData, IntoPipelineData, PipelineData,
+    ShellError, Signature, Span, Spanned, SyntaxShape, Type, Value,
+};
+use std::borrow::Cow;
+
+#[derive(Clone)]
+pub struct HelpAliases;
+
+impl Command for HelpAliases {
+    fn name(&self) -> &str {
+        "help aliases"
+    }
+
+    fn usage(&self) -> &str {
+        "Show help on nushell aliases."
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("help aliases")
+            .category(Category::Core)
+            .rest(
+                "rest",
+                SyntaxShape::String,
+                "the name of alias to get help on",
+            )
+            .named(
+                "find",
+                SyntaxShape::String,
+                "string to find in alias names and usage",
+                Some('f'),
+            )
+            .input_output_types(vec![(Type::Nothing, Type::Table(vec![]))])
+            .allow_variants_without_examples(true)
+    }
+
+    fn examples(&self) -> Vec<Example> {
+        vec![
+            Example {
+                description: "show all aliases",
+                example: "help aliases",
+                result: None,
+            },
+            Example {
+                description: "show help for single alias",
+                example: "help aliases my-alias",
+                result: None,
+            },
+            Example {
+                description: "search for string in alias names and usages",
+                example: "help aliases --find my-alias",
+                result: None,
+            },
+        ]
+    }
+
+    fn run(
+        &self,
+        engine_state: &EngineState,
+        stack: &mut Stack,
+        call: &Call,
+        _input: PipelineData,
+    ) -> Result<PipelineData, ShellError> {
+        help_aliases(engine_state, stack, call)
+    }
+}
+
+pub fn help_aliases(
+    engine_state: &EngineState,
+    stack: &mut Stack,
+    call: &Call,
+) -> Result<PipelineData, ShellError> {
+    let head = call.head;
+    let find: Option<Spanned<String>> = call.get_flag(engine_state, stack, "find")?;
+    let rest: Vec<Spanned<String>> = call.rest(engine_state, stack, 0)?;
+
+    // 🚩The following two-lines are copied from filters/find.rs:
+    let style_computer = StyleComputer::from_config(engine_state, stack);
+    // Currently, search results all use the same style.
+    // Also note that this sample string is passed into user-written code (the closure that may or may not be
+    // defined for "string").
+    let string_style = style_computer.compute("string", &Value::string("search result", head));
+
+    if let Some(f) = find {
+        let all_cmds_vec = build_help_aliases(engine_state, stack, head);
+        let found_cmds_vec =
+            highlight_search_in_table(all_cmds_vec, &f.item, &["name", "usage"], &string_style)?;
+
+        return Ok(found_cmds_vec
+            .into_iter()
+            .into_pipeline_data(engine_state.ctrlc.clone()));
+    }
+
+    if rest.is_empty() {
+        let found_cmds_vec = build_help_aliases(engine_state, stack, head);
+
+        Ok(found_cmds_vec
+            .into_iter()
+            .into_pipeline_data(engine_state.ctrlc.clone()))
+    } else {
+        let mut name = String::new();
+
+        for r in &rest {
+            if !name.is_empty() {
+                name.push(' ');
+            }
+            name.push_str(&r.item);
+        }
+
+        let alias_id = if let Some(id) = engine_state.find_alias(name.as_bytes(), &[]) {
+            id
+        } else {
+            return Err(ShellError::AliasNotFound(span(
+                &rest.iter().map(|r| r.span).collect::<Vec<Span>>(),
+            )));
+        };
+
+        let alias_expansion = engine_state
+            .get_alias(alias_id)
+            .iter()
+            .map(|span| String::from_utf8_lossy(engine_state.get_span_contents(span)))
+            .collect::<Vec<Cow<str>>>()
+            .join(" ");
+
+        let alias_usage = engine_state.build_alias_usage(alias_id);
+
+        // TODO: merge this into documentation.rs at some point
+        const G: &str = "\x1b[32m"; // green
+        const C: &str = "\x1b[36m"; // cyan
+        const RESET: &str = "\x1b[0m"; // reset
+
+        let mut long_desc = String::new();
+
+        if let Some((usage, extra_usage)) = alias_usage {
+            long_desc.push_str(&usage);
+            long_desc.push_str("\n\n");
+
+            if !extra_usage.is_empty() {
+                long_desc.push_str(&extra_usage);
+                long_desc.push_str("\n\n");
+            }
+        }
+
+        long_desc.push_str(&format!("{G}Alias{RESET}: {C}{name}{RESET}"));
+        long_desc.push_str("\n\n");
+        long_desc.push_str(&format!("{G}Expansion{RESET}:\n  {alias_expansion}"));
+
+        let config = engine_state.get_config();
+        if !config.use_ansi_coloring {
+            long_desc = nu_utils::strip_ansi_string_likely(long_desc);
+        }
+
+        Ok(Value::String {
+            val: long_desc,
+            span: call.head,
+        }
+        .into_pipeline_data())
+    }
+}
+
+fn build_help_aliases(engine_state: &EngineState, stack: &Stack, span: Span) -> Vec<Value> {
+    let mut scope_data = ScopeData::new(engine_state, stack);
+    scope_data.populate_aliases();
+
+    scope_data.collect_aliases(span)
+}
+
+#[cfg(test)]
+mod test {
+    #[test]
+    fn test_examples() {
+        use super::HelpAliases;
+        use crate::test_examples;
+        test_examples(HelpAliases {})
+    }
+}

crates/nu-command/src/core_commands/help_commands.rs

@@ -0,0 +1,185 @@
+use crate::help::highlight_search_in_table;
+use nu_color_config::StyleComputer;
+use nu_engine::{get_full_help, CallExt};
+use nu_protocol::{
+    ast::Call,
+    engine::{Command, EngineState, Stack},
+    span, Category, IntoInterruptiblePipelineData, IntoPipelineData, PipelineData, ShellError,
+    Signature, Span, Spanned, SyntaxShape, Type, Value,
+};
+use std::borrow::Borrow;
+
+#[derive(Clone)]
+pub struct HelpCommands;
+
+impl Command for HelpCommands {
+    fn name(&self) -> &str {
+        "help commands"
+    }
+
+    fn usage(&self) -> &str {
+        "Show help on nushell commands."
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("help commands")
+            .category(Category::Core)
+            .rest(
+                "rest",
+                SyntaxShape::String,
+                "the name of command to get help on",
+            )
+            .named(
+                "find",
+                SyntaxShape::String,
+                "string to find in command names, usage, and search terms",
+                Some('f'),
+            )
+            .input_output_types(vec![(Type::Nothing, Type::Table(vec![]))])
+            .allow_variants_without_examples(true)
+    }
+
+    fn run(
+        &self,
+        engine_state: &EngineState,
+        stack: &mut Stack,
+        call: &Call,
+        _input: PipelineData,
+    ) -> Result<PipelineData, ShellError> {
+        help_commands(engine_state, stack, call)
+    }
+}
+
+pub fn help_commands(
+    engine_state: &EngineState,
+    stack: &mut Stack,
+    call: &Call,
+) -> Result<PipelineData, ShellError> {
+    let head = call.head;
+    let find: Option<Spanned<String>> = call.get_flag(engine_state, stack, "find")?;
+    let rest: Vec<Spanned<String>> = call.rest(engine_state, stack, 0)?;
+
+    // 🚩The following two-lines are copied from filters/find.rs:
+    let style_computer = StyleComputer::from_config(engine_state, stack);
+    // Currently, search results all use the same style.
+    // Also note that this sample string is passed into user-written code (the closure that may or may not be
+    // defined for "string").
+    let string_style = style_computer.compute("string", &Value::string("search result", head));
+
+    if let Some(f) = find {
+        let all_cmds_vec = build_help_commands(engine_state, head);
+        let found_cmds_vec = highlight_search_in_table(
+            all_cmds_vec,
+            &f.item,
+            &["name", "usage", "search_terms"],
+            &string_style,
+        )?;
+
+        return Ok(found_cmds_vec
+            .into_iter()
+            .into_pipeline_data(engine_state.ctrlc.clone()));
+    }
+
+    if rest.is_empty() {
+        let found_cmds_vec = build_help_commands(engine_state, head);
+
+        Ok(found_cmds_vec
+            .into_iter()
+            .into_pipeline_data(engine_state.ctrlc.clone()))
+    } else {
+        let mut name = String::new();
+
+        for r in &rest {
+            if !name.is_empty() {
+                name.push(' ');
+            }
+            name.push_str(&r.item);
+        }
+
+        let output = engine_state
+            .get_signatures_with_examples(false)
+            .iter()
+            .filter(|(signature, _, _, _, _)| signature.name == name)
+            .map(|(signature, examples, _, _, is_parser_keyword)| {
+                get_full_help(signature, examples, engine_state, stack, *is_parser_keyword)
+            })
+            .collect::<Vec<String>>();
+
+        if !output.is_empty() {
+            Ok(Value::String {
+                val: output.join("======================\n\n"),
+                span: call.head,
+            }
+            .into_pipeline_data())
+        } else {
+            Err(ShellError::CommandNotFound(span(&[
+                rest[0].span,
+                rest[rest.len() - 1].span,
+            ])))
+        }
+    }
+}
+
+fn build_help_commands(engine_state: &EngineState, span: Span) -> Vec<Value> {
+    let commands = engine_state.get_decls_sorted(false);
+    let mut found_cmds_vec = Vec::new();
+
+    for (name_bytes, decl_id) in commands {
+        let mut cols = vec![];
+        let mut vals = vec![];
+
+        let name = String::from_utf8_lossy(&name_bytes).to_string();
+        let decl = engine_state.get_decl(decl_id);
+        let sig = decl.signature().update_from_command(name, decl.borrow());
+
+        let signatures = sig.to_string().trim_start().replace("\n  ", "\n");
+        let key = sig.name;
+        let usage = sig.usage;
+        let search_terms = sig.search_terms;
+
+        cols.push("name".into());
+        vals.push(Value::String { val: key, span });
+
+        cols.push("category".into());
+        vals.push(Value::string(sig.category.to_string(), span));
+
+        cols.push("command_type".into());
+        vals.push(Value::String {
+            val: format!("{:?}", decl.command_type()).to_lowercase(),
+            span,
+        });
+
+        cols.push("usage".into());
+        vals.push(Value::String { val: usage, span });
+
+        cols.push("signatures".into());
+        vals.push(Value::String {
+            val: if decl.is_parser_keyword() {
+                "".to_string()
+            } else {
+                signatures
+            },
+            span,
+        });
+
+        cols.push("search_terms".into());
+        vals.push(Value::String {
+            val: search_terms.join(", "),
+            span,
+        });
+
+        found_cmds_vec.push(Value::Record { cols, vals, span });
+    }
+
+    found_cmds_vec
+}
+
+#[cfg(test)]
+mod test {
+    #[test]
+    fn test_examples() {
+        use super::HelpCommands;
+        use crate::test_examples;
+        test_examples(HelpCommands {})
+    }
+}

crates/nu-command/src/core_commands/help_modules.rs

@@ -0,0 +1,254 @@
+use crate::help::highlight_search_in_table;
+use nu_color_config::StyleComputer;
+use nu_engine::{scope::ScopeData, CallExt};
+use nu_protocol::{
+    ast::Call,
+    engine::{Command, EngineState, Stack},
+    span, AliasId, Category, DeclId, Example, IntoInterruptiblePipelineData, IntoPipelineData,
+    PipelineData, ShellError, Signature, Span, Spanned, SyntaxShape, Type, Value,
+};
+
+#[derive(Clone)]
+pub struct HelpModules;
+
+impl Command for HelpModules {
+    fn name(&self) -> &str {
+        "help modules"
+    }
+
+    fn usage(&self) -> &str {
+        "Show help on nushell modules."
+    }
+
+    fn extra_usage(&self) -> &str {
+        r#"When requesting help for a single module, its commands and aliases will be highlighted if they
+are also available in the current scope. Commands/aliases that were imported under a different name
+(such as with a prefix after `use some-module`) will be highlighted in parentheses."#
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("help modules")
+            .category(Category::Core)
+            .rest(
+                "rest",
+                SyntaxShape::String,
+                "the name of module to get help on",
+            )
+            .named(
+                "find",
+                SyntaxShape::String,
+                "string to find in module names and usage",
+                Some('f'),
+            )
+            .input_output_types(vec![(Type::Nothing, Type::Table(vec![]))])
+            .allow_variants_without_examples(true)
+    }
+
+    fn examples(&self) -> Vec<Example> {
+        vec![
+            Example {
+                description: "show all modules",
+                example: "help modules",
+                result: None,
+            },
+            Example {
+                description: "show help for single module",
+                example: "help modules my-module",
+                result: None,
+            },
+            Example {
+                description: "search for string in module names and usages",
+                example: "help modules --find my-module",
+                result: None,
+            },
+        ]
+    }
+
+    fn run(
+        &self,
+        engine_state: &EngineState,
+        stack: &mut Stack,
+        call: &Call,
+        _input: PipelineData,
+    ) -> Result<PipelineData, ShellError> {
+        help_modules(engine_state, stack, call)
+    }
+}
+
+pub fn help_modules(
+    engine_state: &EngineState,
+    stack: &mut Stack,
+    call: &Call,
+) -> Result<PipelineData, ShellError> {
+    let head = call.head;
+    let find: Option<Spanned<String>> = call.get_flag(engine_state, stack, "find")?;
+    let rest: Vec<Spanned<String>> = call.rest(engine_state, stack, 0)?;
+
+    // 🚩The following two-lines are copied from filters/find.rs:
+    let style_computer = StyleComputer::from_config(engine_state, stack);
+    // Currently, search results all use the same style.
+    // Also note that this sample string is passed into user-written code (the closure that may or may not be
+    // defined for "string").
+    let string_style = style_computer.compute("string", &Value::string("search result", head));
+
+    if let Some(f) = find {
+        let all_cmds_vec = build_help_modules(engine_state, stack, head);
+        let found_cmds_vec =
+            highlight_search_in_table(all_cmds_vec, &f.item, &["name", "usage"], &string_style)?;
+
+        return Ok(found_cmds_vec
+            .into_iter()
+            .into_pipeline_data(engine_state.ctrlc.clone()));
+    }
+
+    if rest.is_empty() {
+        let found_cmds_vec = build_help_modules(engine_state, stack, head);
+
+        Ok(found_cmds_vec
+            .into_iter()
+            .into_pipeline_data(engine_state.ctrlc.clone()))
+    } else {
+        let mut name = String::new();
+
+        for r in &rest {
+            if !name.is_empty() {
+                name.push(' ');
+            }
+            name.push_str(&r.item);
+        }
+
+        let module_id = if let Some(id) = engine_state.find_module(name.as_bytes(), &[]) {
+            id
+        } else {
+            return Err(ShellError::ModuleNotFoundAtRuntime(
+                name,
+                span(&rest.iter().map(|r| r.span).collect::<Vec<Span>>()),
+            ));
+        };
+
+        let module = engine_state.get_module(module_id);
+
+        let module_usage = engine_state.build_module_usage(module_id);
+
+        // TODO: merge this into documentation.rs at some point
+        const G: &str = "\x1b[32m"; // green
+        const C: &str = "\x1b[36m"; // cyan
+        const CB: &str = "\x1b[1;36m"; // cyan bold
+        const RESET: &str = "\x1b[0m"; // reset
+
+        let mut long_desc = String::new();
+
+        if let Some((usage, extra_usage)) = module_usage {
+            long_desc.push_str(&usage);
+            long_desc.push_str("\n\n");
+
+            if !extra_usage.is_empty() {
+                long_desc.push_str(&extra_usage);
+                long_desc.push_str("\n\n");
+            }
+        }
+
+        long_desc.push_str(&format!("{G}Module{RESET}: {C}{name}{RESET}"));
+        long_desc.push_str("\n\n");
+
+        if !module.decls.is_empty() || module.main.is_some() {
+            let commands: Vec<(Vec<u8>, DeclId)> = engine_state.get_decls_sorted(false).collect();
+
+            let mut module_commands = module.decls();
+            module_commands.sort_by(|a, b| a.0.cmp(&b.0));
+
+            let commands_str = module_commands
+                .iter()
+                .map(|(name_bytes, id)| {
+                    let name = String::from_utf8_lossy(name_bytes);
+                    if let Some((used_name_bytes, _)) =
+                        commands.iter().find(|(_, decl_id)| id == decl_id)
+                    {
+                        if engine_state.find_decl(name.as_bytes(), &[]).is_some() {
+                            format!("{CB}{name}{RESET}")
+                        } else {
+                            let command_name = String::from_utf8_lossy(used_name_bytes);
+                            format!("{name} ({CB}{command_name}{RESET})")
+                        }
+                    } else {
+                        format!("{name}")
+                    }
+                })
+                .collect::<Vec<String>>()
+                .join(", ");
+
+            long_desc.push_str(&format!("{G}Exported commands{RESET}:\n  {commands_str}"));
+            long_desc.push_str("\n\n");
+        }
+
+        if !module.aliases.is_empty() {
+            let aliases: Vec<(Vec<u8>, AliasId)> = engine_state.get_aliases_sorted(false).collect();
+
+            let mut module_aliases: Vec<(&[u8], AliasId)> = module
+                .aliases
+                .iter()
+                .map(|(name, id)| (name.as_ref(), *id))
+                .collect();
+            module_aliases.sort_by(|a, b| a.0.cmp(b.0));
+
+            let aliases_str = module_aliases
+                .iter()
+                .map(|(name_bytes, id)| {
+                    let name = String::from_utf8_lossy(name_bytes);
+                    if let Some((used_name_bytes, _)) =
+                        aliases.iter().find(|(_, alias_id)| id == alias_id)
+                    {
+                        if engine_state.find_alias(name.as_bytes(), &[]).is_some() {
+                            format!("{CB}{name}{RESET}")
+                        } else {
+                            let alias_name = String::from_utf8_lossy(used_name_bytes);
+                            format!("{name} ({CB}{alias_name}{RESET})")
+                        }
+                    } else {
+                        format!("{name}")
+                    }
+                })
+                .collect::<Vec<String>>()
+                .join(", ");
+
+            long_desc.push_str(&format!("{G}Exported aliases{RESET}:\n  {aliases_str}"));
+            long_desc.push_str("\n\n");
+        }
+
+        if module.env_block.is_some() {
+            long_desc.push_str(&format!("This module {C}exports{RESET} environment."));
+        } else {
+            long_desc.push_str(&format!(
+                "This module {C}does not export{RESET} environment."
+            ));
+        }
+
+        let config = engine_state.get_config();
+        if !config.use_ansi_coloring {
+            long_desc = nu_utils::strip_ansi_string_likely(long_desc);
+        }
+
+        Ok(Value::String {
+            val: long_desc,
+            span: call.head,
+        }
+        .into_pipeline_data())
+    }
+}
+
+fn build_help_modules(engine_state: &EngineState, stack: &Stack, span: Span) -> Vec<Value> {
+    let mut scope_data = ScopeData::new(engine_state, stack);
+    scope_data.populate_modules();
+
+    scope_data.collect_modules(span)
+}
+
+#[cfg(test)]
+mod test {
+    #[test]
+    fn test_examples() {
+        use super::HelpModules;
+        use crate::test_examples;
+        test_examples(HelpModules {})
+    }
+}

crates/nu-command/src/core_commands/help_operators.rs

@@ -1,7 +1,7 @@
 use nu_protocol::{
     ast::Call,
     engine::{Command, EngineState, Stack},
-    Category, IntoInterruptiblePipelineData, PipelineData, ShellError, Signature, Value,
+    Category, IntoInterruptiblePipelineData, PipelineData, ShellError, Signature, Type, Value,
 };
 
 #[derive(Clone)]
@@ -17,7 +17,10 @@ impl Command for HelpOperators {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("help operators").category(Category::Core)
+        Signature::build("help operators")
+            .category(Category::Core)
+            .input_output_types(vec![(Type::Nothing, Type::Table(vec![]))])
+            .allow_variants_without_examples(true)
     }
 
     fn run(

crates/nu-command/src/core_commands/hide.rs

@@ -1,8 +1,6 @@
-use nu_protocol::ast::{Call, Expr, Expression};
+use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{
-    Category, Example, PipelineData, ShellError, Signature, Span, Spanned, SyntaxShape, Type, Value,
-};
+use nu_protocol::{Category, Example, PipelineData, Signature, SyntaxShape, Type};
 
 #[derive(Clone)]
 pub struct Hide;
@@ -15,7 +13,12 @@ impl Command for Hide {
     fn signature(&self) -> nu_protocol::Signature {
         Signature::build("hide")
             .input_output_types(vec![(Type::Nothing, Type::Nothing)])
-            .required("pattern", SyntaxShape::ImportPattern, "import pattern")
+            .required("module", SyntaxShape::String, "Module or module file")
+            .optional(
+                "members",
+                SyntaxShape::Any,
+                "Which members of the module to import",
+            )
             .category(Category::Core)
     }
 
@@ -36,32 +39,11 @@ This command is a parser keyword. For details, check:
 
     fn run(
         &self,
-        engine_state: &EngineState,
-        stack: &mut Stack,
-        call: &Call,
+        _engine_state: &EngineState,
+        _stack: &mut Stack,
+        _call: &Call,
         _input: PipelineData,
     ) -> Result<nu_protocol::PipelineData, nu_protocol::ShellError> {
-        let env_var_name = if let Some(Expression {
-            expr: Expr::ImportPattern(pat),
-            ..
-        }) = call.positional_nth(0)
-        {
-            Spanned {
-                item: String::from_utf8_lossy(&pat.head.name).to_string(),
-                span: pat.head.span,
-            }
-        } else {
-            return Err(ShellError::GenericError(
-                "Unexpected import".into(),
-                "import pattern not supported".into(),
-                Some(call.head),
-                None,
-                Vec::new(),
-            ));
-        };
-
-        stack.remove_env_var(engine_state, &env_var_name.item);
-
         Ok(PipelineData::empty())
     }
 
@@ -77,11 +59,6 @@ This command is a parser keyword. For details, check:
                 example: r#"def say-hi [] { echo 'Hi!' }; hide say-hi"#,
                 result: None,
             },
-            Example {
-                description: "Hide an environment variable",
-                example: r#"let-env HZ_ENV_ABC = 1; hide HZ_ENV_ABC; 'HZ_ENV_ABC' in (env).name"#,
-                result: Some(Value::boolean(false, Span::test_data())),
-            },
         ]
     }
 }

crates/nu-command/src/core_commands/hide_env.rs

@@ -2,8 +2,8 @@ use nu_engine::CallExt;
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
 use nu_protocol::{
-    did_you_mean, Category, Example, PipelineData, ShellError, Signature, Span, Spanned,
-    SyntaxShape, Type, Value,
+    did_you_mean, Category, Example, PipelineData, ShellError, Signature, Spanned, SyntaxShape,
+    Type, Value,
 };
 
 #[derive(Clone)]
@@ -70,7 +70,7 @@ impl Command for HideEnv {
         vec![Example {
             description: "Hide an environment variable",
             example: r#"let-env HZ_ENV_ABC = 1; hide-env HZ_ENV_ABC; 'HZ_ENV_ABC' in (env).name"#,
-            result: Some(Value::boolean(false, Span::test_data())),
+            result: Some(Value::test_bool(false)),
         }]
     }
 }

crates/nu-command/src/core_commands/let_.rs

@@ -70,9 +70,8 @@ impl Command for Let {
         )?
         .0;
 
-        //println!("Adding: {:?} to {}", rhs, var_id);
-
         stack.add_var(var_id, rhs.into_value(call.head));
+
         Ok(PipelineData::empty())
     }
 

crates/nu-command/src/core_commands/loop_.rs

@@ -2,7 +2,7 @@ use nu_engine::{eval_block, CallExt};
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Block, Command, EngineState, Stack};
 use nu_protocol::{
-    Category, Example, PipelineData, ShellError, Signature, Span, SyntaxShape, Value,
+    Category, Example, PipelineData, ShellError, Signature, SyntaxShape, Type, Value,
 };
 
 #[derive(Clone)]
@@ -19,6 +19,8 @@ impl Command for Loop {
 
     fn signature(&self) -> nu_protocol::Signature {
         Signature::build("loop")
+            .input_output_types(vec![(Type::Nothing, Type::Nothing)])
+            .allow_variants_without_examples(true)
             .required("block", SyntaxShape::Block, "block to loop")
             .category(Category::Core)
     }
@@ -79,7 +81,7 @@ impl Command for Loop {
         vec![Example {
             description: "Loop while a condition is true",
             example: "mut x = 0; loop { if $x > 10 { break }; $x = $x + 1 }; $x",
-            result: Some(Value::int(11, Span::test_data())),
+            result: Some(Value::test_int(11)),
         }]
     }
 }

crates/nu-command/src/core_commands/metadata.rs

@@ -106,7 +106,7 @@ impl Command for Metadata {
         vec![
             Example {
                 description: "Get the metadata of a variable",
-                example: "metadata $a",
+                example: "let a = 42; metadata $a",
                 result: None,
             },
             Example {

crates/nu-command/src/core_commands/mod.rs

@@ -2,6 +2,7 @@ mod alias;
 mod ast;
 mod break_;
 mod commandline;
+mod const_;
 mod continue_;
 mod debug;
 mod def;
@@ -19,6 +20,9 @@ mod export_use;
 mod extern_;
 mod for_;
 pub mod help;
+pub mod help_aliases;
+pub mod help_commands;
+pub mod help_modules;
 mod help_operators;
 mod hide;
 mod hide_env;
@@ -40,6 +44,7 @@ pub use alias::Alias;
 pub use ast::Ast;
 pub use break_::Break;
 pub use commandline::Commandline;
+pub use const_::Const;
 pub use continue_::Continue;
 pub use debug::Debug;
 pub use def::Def;
@@ -57,6 +62,9 @@ pub use export_use::ExportUse;
 pub use extern_::Extern;
 pub use for_::For;
 pub use help::Help;
+pub use help_aliases::HelpAliases;
+pub use help_commands::HelpCommands;
+pub use help_modules::HelpModules;
 pub use help_operators::HelpOperators;
 pub use hide::Hide;
 pub use hide_env::HideEnv;

crates/nu-command/src/core_commands/module.rs

@@ -1,6 +1,6 @@
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{Category, Example, PipelineData, Signature, Span, SyntaxShape, Type, Value};
+use nu_protocol::{Category, Example, PipelineData, Signature, SyntaxShape, Type, Value};
 
 #[derive(Clone)]
 pub struct Module;
@@ -46,17 +46,17 @@ impl Command for Module {
             Example {
                 description: "Define a custom command in a module and call it",
                 example: r#"module spam { export def foo [] { "foo" } }; use spam foo; foo"#,
-                result: Some(Value::string("foo", Span::test_data())),
+                result: Some(Value::test_string("foo")),
             },
             Example {
                 description: "Define an environment variable in a module",
                 example: r#"module foo { export-env { let-env FOO = "BAZ" } }; use foo; $env.FOO"#,
-                result: Some(Value::string("BAZ", Span::test_data())),
+                result: Some(Value::test_string("BAZ")),
             },
             Example {
                 description: "Define a custom command that participates in the environment in a module and call it",
                 example: r#"module foo { export def-env bar [] { let-env FOO_BAR = "BAZ" } }; use foo bar; bar; $env.FOO_BAR"#,
-                result: Some(Value::string("BAZ", Span::test_data())),
+                result: Some(Value::test_string("BAZ")),
             },
         ]
     }