Update main.wxs (#4007)

Remove references to the old binaries

.github/ISSUE_TEMPLATE/bug_report.yml

@@ -4,14 +4,14 @@ body:
   - type: textarea
     id: description
     attributes:
-      label: Describe the Bug
+      label: Describe the bug
       description: A clear and concise description of what the bug is.
     validations:
       required: true
   - type: textarea
     id: repro
     attributes:
-      label: To Reproduce
+      label: How to reproduce
       description: Steps to reproduce the behavior
       placeholder: |
         1.
@@ -38,11 +38,11 @@ body:
     id: config
     attributes:
       label: Configuration
-      description: "Please run `> version | pivot` and paste the output to show OS, features, etc"
+      description: "Please run `> version | pivot key value | to md` and paste the output to show OS, features, etc"
       placeholder: |
-        > version | pivot
+        > version | pivot key value | to md
         ╭───┬────────────────────┬───────────────────────────────────────────────────────────────────────╮
-        │ # │ Column0            │ Column1                                                               │
+        │ # │ key                │ value                                                                 │
         ├───┼────────────────────┼───────────────────────────────────────────────────────────────────────┤
         │ 0 │ version            │ 0.24.1                                                                │
         │ 1 │ build_os           │ macos-x86_64                                                          │
@@ -59,7 +59,7 @@ body:
   - type: textarea
     id: context
     attributes:
-      label: Additional Context
+      label: Additional context
       description: Add any other context about the problem here.
     validations:
       required: false

.github/ISSUE_TEMPLATE/feature_request.yml

@@ -4,7 +4,7 @@ body:
   - type: textarea
     id: problem
     attributes:
-      label: Related Problem
+      label: Related problem
       description: Is your feature request related to a problem? Please describe.
       placeholder: |
         A clear and concise description of what the problem is.
@@ -28,7 +28,7 @@ body:
   - type: textarea
     id: context
     attributes:
-      label: Additional Context and Details
+      label: Additional context and details
       description: Add any other context or screenshots about the feature request here.
     validations:
       required: false

Cargo.toml

@@ -10,7 +10,7 @@ license = "MIT"
 name = "nu"
 readme = "README.md"
 repository = "https://github.com/nushell/nushell"
-version = "0.35.0"
+version = "0.37.0"
 
 [workspace]
 members = ["crates/*/"]
@@ -18,38 +18,34 @@ members = ["crates/*/"]
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
-nu-cli = { version = "0.35.0", path="./crates/nu-cli", default-features=false }
-nu-command = { version = "0.35.0", path="./crates/nu-command" }
-nu-completion = { version = "0.35.0", path="./crates/nu-completion" }
-nu-data = { version = "0.35.0", path="./crates/nu-data" }
-nu-engine = { version = "0.35.0", path="./crates/nu-engine" }
-nu-errors = { version = "0.35.0", path="./crates/nu-errors" }
-nu-parser = { version = "0.35.0", path="./crates/nu-parser" }
-nu-path = { version = "0.35.0", path="./crates/nu-path" }
-nu-plugin = { version = "0.35.0", path="./crates/nu-plugin" }
-nu-protocol = { version = "0.35.0", path="./crates/nu-protocol" }
-nu-source = { version = "0.35.0", path="./crates/nu-source" }
-nu-value-ext = { version = "0.35.0", path="./crates/nu-value-ext" }
+nu-cli = { version = "0.37.0", path="./crates/nu-cli", default-features=false }
+nu-command = { version = "0.37.0", path="./crates/nu-command" }
+nu-completion = { version = "0.37.0", path="./crates/nu-completion" }
+nu-data = { version = "0.37.0", path="./crates/nu-data" }
+nu-engine = { version = "0.37.0", path="./crates/nu-engine" }
+nu-errors = { version = "0.37.0", path="./crates/nu-errors" }
+nu-parser = { version = "0.37.0", path="./crates/nu-parser" }
+nu-path = { version = "0.37.0", path="./crates/nu-path" }
+nu-plugin = { version = "0.37.0", path="./crates/nu-plugin" }
+nu-protocol = { version = "0.37.0", path="./crates/nu-protocol" }
+nu-source = { version = "0.37.0", path="./crates/nu-source" }
+nu-value-ext = { version = "0.37.0", path="./crates/nu-value-ext" }
 
-nu_plugin_binaryview = { version = "0.35.0", path="./crates/nu_plugin_binaryview", optional=true }
-nu_plugin_chart = { version = "0.35.0", path="./crates/nu_plugin_chart", optional=true }
-nu_plugin_fetch = { version = "0.35.0", path="./crates/nu_plugin_fetch", optional=true }
-nu_plugin_from_bson = { version = "0.35.0", path="./crates/nu_plugin_from_bson", optional=true }
-nu_plugin_from_sqlite = { version = "0.35.0", path="./crates/nu_plugin_from_sqlite", optional=true }
-nu_plugin_inc = { version = "0.35.0", path="./crates/nu_plugin_inc", optional=true }
-nu_plugin_match = { version = "0.35.0", path="./crates/nu_plugin_match", optional=true }
-nu_plugin_post = { version = "0.35.0", path="./crates/nu_plugin_post", optional=true }
-nu_plugin_ps = { version = "0.35.0", path="./crates/nu_plugin_ps", optional=true }
-nu_plugin_query_json = { version = "0.35.0", path="./crates/nu_plugin_query_json", optional=true }
-nu_plugin_s3 = { version = "0.35.0", path="./crates/nu_plugin_s3", optional=true }
-nu_plugin_selector = { version = "0.35.0", path="./crates/nu_plugin_selector", optional=true }
-nu_plugin_start = { version = "0.35.0", path="./crates/nu_plugin_start", optional=true }
-nu_plugin_sys = { version = "0.35.0", path="./crates/nu_plugin_sys", optional=true }
-nu_plugin_textview = { version = "0.35.0", path="./crates/nu_plugin_textview", optional=true }
-nu_plugin_to_bson = { version = "0.35.0", path="./crates/nu_plugin_to_bson", optional=true }
-nu_plugin_to_sqlite = { version = "0.35.0", path="./crates/nu_plugin_to_sqlite", optional=true }
-nu_plugin_tree = { version = "0.35.0", path="./crates/nu_plugin_tree", optional=true }
-nu_plugin_xpath = { version = "0.35.0", path="./crates/nu_plugin_xpath", optional=true }
+nu_plugin_binaryview = { version = "0.37.0", path="./crates/nu_plugin_binaryview", optional=true }
+nu_plugin_chart = { version = "0.37.0", path="./crates/nu_plugin_chart", optional=true }
+nu_plugin_from_bson = { version = "0.37.0", path="./crates/nu_plugin_from_bson", optional=true }
+nu_plugin_from_sqlite = { version = "0.37.0", path="./crates/nu_plugin_from_sqlite", optional=true }
+nu_plugin_inc = { version = "0.37.0", path="./crates/nu_plugin_inc", optional=true }
+nu_plugin_match = { version = "0.37.0", path="./crates/nu_plugin_match", optional=true }
+nu_plugin_query_json = { version = "0.37.0", path="./crates/nu_plugin_query_json", optional=true }
+nu_plugin_s3 = { version = "0.37.0", path="./crates/nu_plugin_s3", optional=true }
+nu_plugin_selector = { version = "0.37.0", path="./crates/nu_plugin_selector", optional=true }
+nu_plugin_start = { version = "0.37.0", path="./crates/nu_plugin_start", optional=true }
+nu_plugin_textview = { version = "0.37.0", path="./crates/nu_plugin_textview", optional=true }
+nu_plugin_to_bson = { version = "0.37.0", path="./crates/nu_plugin_to_bson", optional=true }
+nu_plugin_to_sqlite = { version = "0.37.0", path="./crates/nu_plugin_to_sqlite", optional=true }
+nu_plugin_tree = { version = "0.37.0", path="./crates/nu_plugin_tree", optional=true }
+nu_plugin_xpath = { version = "0.37.0", path="./crates/nu_plugin_xpath", optional=true }
 
 # Required to bootstrap the main binary
 ctrlc = { version="3.1.7", optional=true }
@@ -57,8 +53,7 @@ futures = { version="0.3.12", features=["compat", "io-compat"] }
 itertools = "0.10.0"
 
 [dev-dependencies]
-nu-test-support = { version = "0.35.0", path="./crates/nu-test-support" }
-dunce = "1.0.1"
+nu-test-support = { version = "0.37.0", path="./crates/nu-test-support" }
 serial_test = "0.5.1"
 hamcrest2 = "0.3.0"
 rstest = "0.10.0"
@@ -66,6 +61,8 @@ rstest = "0.10.0"
 [build-dependencies]
 
 [features]
+fetch-support = ["nu-command/fetch", "nu-command/post"]
+sys-support = ["nu-command/sys", "nu-command/ps"]
 ctrlc-support = ["nu-cli/ctrlc", "nu-command/ctrlc"]
 rustyline-support = ["nu-cli/rustyline-support", "nu-command/rustyline-support"]
 term-support = ["nu-command/term"]
@@ -74,15 +71,13 @@ which-support = ["nu-command/which", "nu-engine/which"]
 
 default = [
     "nu-cli/shadow-rs",
-    "sys",
-    "ps",
+    "sys-support",
     "ctrlc-support",
     "which-support",
     "term-support",
     "rustyline-support",
     "match",
-    "post",
-    "fetch",
+    "fetch-support",
     "zip-support",
     "dataframe",
 ]
@@ -110,12 +105,8 @@ extra = [
 wasi = ["inc", "match", "match", "tree", "rustyline-support"]
 
 # Stable (Default)
-fetch = ["nu_plugin_fetch"]
 inc = ["nu_plugin_inc"]
 match = ["nu_plugin_match"]
-post = ["nu_plugin_post"]
-ps = ["nu_plugin_ps"]
-sys = ["nu_plugin_sys"]
 textview = ["nu_plugin_textview"]
 
 # Extra
@@ -146,10 +137,12 @@ dataframe = [
     "nu-command/dataframe",
     "nu-value-ext/dataframe",
     "nu-data/dataframe",
-    "nu_plugin_post/dataframe",
     "nu_plugin_to_bson/dataframe",
 ]
 
+[profile.release]
+opt-level = "z"  # Optimize for size.
+
 # Core plugins that ship with `cargo install nu` by default
 # Currently, Cargo limits us to installing only one binary
 # unless we use [[bin]], so we use this as a workaround
@@ -163,31 +156,11 @@ name = "nu_plugin_core_inc"
 path = "src/plugins/nu_plugin_core_inc.rs"
 required-features = ["inc"]
 
-[[bin]]
-name = "nu_plugin_core_ps"
-path = "src/plugins/nu_plugin_core_ps.rs"
-required-features = ["ps"]
-
-[[bin]]
-name = "nu_plugin_core_sys"
-path = "src/plugins/nu_plugin_core_sys.rs"
-required-features = ["sys"]
-
-[[bin]]
-name = "nu_plugin_core_fetch"
-path = "src/plugins/nu_plugin_core_fetch.rs"
-required-features = ["fetch"]
-
 [[bin]]
 name = "nu_plugin_core_match"
 path = "src/plugins/nu_plugin_core_match.rs"
 required-features = ["match"]
 
-[[bin]]
-name = "nu_plugin_core_post"
-path = "src/plugins/nu_plugin_core_post.rs"
-required-features = ["post"]
-
 # Extra plugins
 
 [[bin]]

README.md

@@ -310,9 +310,15 @@ Nu is in heavy development and will naturally change as it matures and people us
 | Completions   |             |           |  X  |         |        | Completions for filepaths                                            |
 | Type-checking |             |           |  X  |         |        | Commands check basic types, but input/output isn't checked           |
 
-## Current Roadmap
+## Officially Supported By
 
-We've added a `Roadmap Board` to help collaboratively capture the direction we're going for the current release and capture some important issues we'd like to see in Nushell. You can find the Roadmap [here](https://github.com/nushell/nushell/projects/2).
+Please submit an issue or PR to be added to this list.
+
+###   Integrations
+-   [zoxide](https://github.com/ajeetdsouza/zoxide)
+-   [starship](https://github.com/starship/starship)
+###   Mentions
+-   [The Python Launcher for Unix](https://github.com/brettcannon/python-launcher#how-do-i-get-a-table-of-python-executables-in-nushell)
 
 ## Contributing
 

crates/nu-ansi-term/Cargo.toml

@@ -9,7 +9,7 @@ description = "Library for ANSI terminal colors and styles (bold, underline)"
 edition = "2018"
 license = "MIT"
 name = "nu-ansi-term"
-version = "0.35.0"
+version = "0.37.0"
 
 [lib]
 doctest = false

crates/nu-ansi-term/src/ansi.rs

@@ -93,7 +93,7 @@ pub static RESET: &str = "\x1B[0m";
 
 impl Color {
     fn write_foreground_code<W: AnyWrite + ?Sized>(&self, f: &mut W) -> Result<(), W::Error> {
-        match *self {
+        match self {
             Color::Black => write!(f, "30"),
             Color::Red => write!(f, "31"),
             Color::Green => write!(f, "32"),
@@ -103,8 +103,8 @@ impl Color {
             Color::Magenta => write!(f, "35"),
             Color::Cyan => write!(f, "36"),
             Color::White => write!(f, "37"),
-            Color::Fixed(num) => write!(f, "38;5;{}", &num),
-            Color::Rgb(r, g, b) => write!(f, "38;2;{};{};{}", &r, &g, &b),
+            Color::Fixed(num) => write!(f, "38;5;{}", num),
+            Color::Rgb(r, g, b) => write!(f, "38;2;{};{};{}", r, g, b),
             Color::DarkGray => write!(f, "90"),
             Color::LightRed => write!(f, "91"),
             Color::LightGreen => write!(f, "92"),
@@ -118,7 +118,7 @@ impl Color {
     }
 
     fn write_background_code<W: AnyWrite + ?Sized>(&self, f: &mut W) -> Result<(), W::Error> {
-        match *self {
+        match self {
             Color::Black => write!(f, "40"),
             Color::Red => write!(f, "41"),
             Color::Green => write!(f, "42"),
@@ -128,8 +128,8 @@ impl Color {
             Color::Magenta => write!(f, "45"),
             Color::Cyan => write!(f, "46"),
             Color::White => write!(f, "47"),
-            Color::Fixed(num) => write!(f, "48;5;{}", &num),
-            Color::Rgb(r, g, b) => write!(f, "48;2;{};{};{}", &r, &g, &b),
+            Color::Fixed(num) => write!(f, "48;5;{}", num),
+            Color::Rgb(r, g, b) => write!(f, "48;2;{};{};{}", r, g, b),
             Color::DarkGray => write!(f, "100"),
             Color::LightRed => write!(f, "101"),
             Color::LightGreen => write!(f, "102"),

crates/nu-ansi-term/src/display.rs

@@ -297,7 +297,7 @@ mod tests {
     fn no_control_codes_for_plain() {
         let one = Style::default().paint("one");
         let two = Style::default().paint("two");
-        let output = format!("{}", AnsiStrings(&[one, two]));
-        assert_eq!(&*output, "onetwo");
+        let output = AnsiStrings(&[one, two]).to_string();
+        assert_eq!(output, "onetwo");
     }
 }

crates/nu-ansi-term/src/style.rs

@@ -602,14 +602,14 @@ mod serde_json_tests {
 
     #[test]
     fn color_deserialization() {
-        let colors = &[
+        let colors = [
             Color::Red,
             Color::Blue,
             Color::Rgb(123, 123, 123),
             Color::Fixed(255),
         ];
 
-        for color in colors.iter() {
+        for color in colors {
             let serialized = serde_json::to_string(&color).unwrap();
             let deserialized: Color = serde_json::from_str(&serialized).unwrap();
 

crates/nu-ansi-term/src/util.rs

@@ -75,6 +75,6 @@ mod test {
         assert_eq!(unstyled_len(&a), 18);
 
         let l2 = [Black.paint("st"), Red.paint("-second"), White.paint("-t")];
-        assert_eq!(sub_string(3, 11, &a).as_slice(), &l2);
+        assert_eq!(sub_string(3, 11, &a), l2);
     }
 }

crates/nu-cli/Cargo.toml

@@ -4,29 +4,29 @@ description = "CLI for nushell"
 edition = "2018"
 license = "MIT"
 name = "nu-cli"
-version = "0.35.0"
+version = "0.37.0"
 build = "build.rs"
 
 [lib]
 doctest = false
 
 [dependencies]
-nu-completion = { version = "0.35.0", path="../nu-completion" }
-nu-command = { version = "0.35.0", path="../nu-command" }
-nu-data = { version = "0.35.0", path="../nu-data" }
-nu-engine = { version = "0.35.0", path="../nu-engine" }
-nu-errors = { version = "0.35.0", path="../nu-errors" }
-nu-parser = { version = "0.35.0", path="../nu-parser" }
-nu-protocol = { version = "0.35.0", path="../nu-protocol" }
-nu-source = { version = "0.35.0", path="../nu-source" }
-nu-stream = { version = "0.35.0", path="../nu-stream" }
-nu-ansi-term = { version = "0.35.0", path="../nu-ansi-term" }
+nu-completion = { version = "0.37.0", path="../nu-completion" }
+nu-command = { version = "0.37.0", path="../nu-command" }
+nu-data = { version = "0.37.0", path="../nu-data" }
+nu-engine = { version = "0.37.0", path="../nu-engine" }
+nu-errors = { version = "0.37.0", path="../nu-errors" }
+nu-parser = { version = "0.37.0", path="../nu-parser" }
+nu-protocol = { version = "0.37.0", path="../nu-protocol" }
+nu-source = { version = "0.37.0", path="../nu-source" }
+nu-stream = { version = "0.37.0", path="../nu-stream" }
+nu-ansi-term = { version = "0.37.0", path="../nu-ansi-term" }
 
 indexmap ="1.6.1"
 log = "0.4.14"
 pretty_env_logger = "0.4.0"
 strip-ansi-escapes = "0.1.0"
-rustyline = { version="8.1.0", optional=true }
+rustyline = { version="9.0.0", optional=true }
 ctrlc = { version="3.1.7", optional=true }
 shadow-rs = { version="0.6", default-features=false, optional=true }
 serde = { version="1.0.123", features=["derive"] }

crates/nu-cli/src/app.rs

@@ -508,14 +508,14 @@ mod tests {
 
     #[test]
     fn can_use_loglevels() -> Result<(), ShellError> {
-        for level in &["error", "warn", "info", "debug", "trace"] {
+        for level in ["error", "warn", "info", "debug", "trace"] {
             let ui = cli_app();
-            let args = format!("nu --loglevel={}", *level);
+            let args = format!("nu --loglevel={}", level);
             ui.parse(&args)?;
             assert_eq!(ui.loglevel().unwrap(), Ok(level.to_string()));
 
             let ui = cli_app();
-            let args = format!("nu -l {}", *level);
+            let args = format!("nu -l {}", level);
             ui.parse(&args)?;
             assert_eq!(ui.loglevel().unwrap(), Ok(level.to_string()));
         }
@@ -541,11 +541,11 @@ mod tests {
 
     #[test]
     fn can_use_test_binaries() -> Result<(), ShellError> {
-        for binarie_name in &[
+        for binarie_name in [
             "echo_env", "cococo", "iecho", "fail", "nonu", "chop", "repeater", "meow",
         ] {
             let ui = cli_app();
-            let args = format!("nu --testbin={}", *binarie_name);
+            let args = format!("nu --testbin={}", binarie_name);
             ui.parse(&args)?;
             assert_eq!(ui.testbin().unwrap(), Ok(binarie_name.to_string()));
         }

crates/nu-cli/src/app/options.rs

@@ -44,7 +44,7 @@ impl Options {
     }
 
     pub fn get(&self, key: &str) -> Option<Value> {
-        self.inner.borrow().get(key).map(Clone::clone)
+        self.inner.borrow().get(key).cloned()
     }
 
     pub fn put(&self, key: &str, value: Value) {

crates/nu-cli/src/app/options_parser.rs

@@ -67,48 +67,37 @@ impl OptionsParser for NuParser {
                             }
                         };
 
-                        let value =
-                            value
-                                .map(|v| match k.as_ref() {
-                                    "testbin" => {
-                                        if let Ok(name) = v.as_string() {
-                                            if testbins().iter().any(|n| name == *n) {
-                                                Some(v)
-                                            } else {
-                                                Some(
-                                                    UntaggedValue::Error(
-                                                        ShellError::untagged_runtime_error(
-                                                            format!("{} is not supported.", name),
-                                                        ),
-                                                    )
-                                                    .into_value(v.tag),
-                                                )
-                                            }
-                                        } else {
-                                            Some(v)
-                                        }
+                        let value = value.map(|v| match k.as_ref() {
+                            "testbin" => {
+                                if let Ok(name) = v.as_string() {
+                                    if testbins().iter().any(|n| name == *n) {
+                                        v
+                                    } else {
+                                        UntaggedValue::Error(ShellError::untagged_runtime_error(
+                                            format!("{} is not supported.", name),
+                                        ))
+                                        .into_value(v.tag)
                                     }
-                                    "loglevel" => {
-                                        if let Ok(name) = v.as_string() {
-                                            if loglevels().iter().any(|n| name == *n) {
-                                                Some(v)
-                                            } else {
-                                                Some(
-                                                    UntaggedValue::Error(
-                                                        ShellError::untagged_runtime_error(
-                                                            format!("{} is not supported.", name),
-                                                        ),
-                                                    )
-                                                    .into_value(v.tag),
-                                                )
-                                            }
-                                        } else {
-                                            Some(v)
-                                        }
+                                } else {
+                                    v
+                                }
+                            }
+                            "loglevel" => {
+                                if let Ok(name) = v.as_string() {
+                                    if loglevels().iter().any(|n| name == *n) {
+                                        v
+                                    } else {
+                                        UntaggedValue::Error(ShellError::untagged_runtime_error(
+                                            format!("{} is not supported.", name),
+                                        ))
+                                        .into_value(v.tag)
                                     }
-                                    _ => Some(v),
-                                })
-                                .flatten();
+                                } else {
+                                    v
+                                }
+                            }
+                            _ => v,
+                        });
 
                         if let Some(value) = value {
                             options.put(k, value);

crates/nu-cli/src/cli.rs

@@ -31,9 +31,12 @@ use std::error::Error;
 use std::iter::Iterator;
 use std::path::PathBuf;
 
+// Name of environment variable where the prompt could be stored
+#[cfg(feature = "rustyline-support")]
+const PROMPT_COMMAND: &str = "PROMPT_COMMAND";
+
 pub fn search_paths() -> Vec<std::path::PathBuf> {
     use std::env;
-
     let mut search_paths = Vec::new();
 
     // Automatically add path `nu` is in as a search path
@@ -83,6 +86,66 @@ pub fn run_script_file(
     Ok(())
 }
 
+#[cfg(feature = "rustyline-support")]
+fn default_prompt_string(cwd: &str) -> String {
+    format!(
+        "{}{}{}{}{}{}> ",
+        Color::Green.bold().prefix().to_string(),
+        cwd,
+        nu_ansi_term::ansi::RESET,
+        Color::Cyan.bold().prefix().to_string(),
+        current_branch(),
+        nu_ansi_term::ansi::RESET
+    )
+}
+
+#[cfg(feature = "rustyline-support")]
+fn evaluate_prompt_string(prompt_line: &str, context: &EvaluationContext, cwd: &str) -> String {
+    context.scope.enter_scope();
+    let (prompt_block, err) = nu_parser::parse(prompt_line, 0, &context.scope);
+
+    if err.is_some() {
+        context.scope.exit_scope();
+        default_prompt_string(cwd)
+    } else {
+        let run_result = run_block(
+            &prompt_block,
+            context,
+            InputStream::empty(),
+            ExternalRedirection::Stdout,
+        );
+        context.scope.exit_scope();
+
+        match run_result {
+            Ok(result) => match result.collect_string(Tag::unknown()) {
+                Ok(string_result) => {
+                    let errors = context.get_errors();
+                    maybe_print_errors(context, Text::from(prompt_line));
+                    context.clear_errors();
+
+                    if !errors.is_empty() {
+                        "> ".into()
+                    } else {
+                        string_result.item
+                    }
+                }
+                Err(e) => {
+                    context.host().lock().print_err(e, &Text::from(prompt_line));
+                    context.clear_errors();
+
+                    "> ".into()
+                }
+            },
+            Err(e) => {
+                context.host().lock().print_err(e, &Text::from(prompt_line));
+                context.clear_errors();
+
+                "> ".into()
+            }
+        }
+    }
+}
+
 #[cfg(feature = "rustyline-support")]
 pub fn cli(
     context: EvaluationContext,
@@ -102,7 +165,10 @@ pub fn cli(
     // Store cmd duration in an env var
     context.scope.add_env_var(
         "CMD_DURATION_MS",
-        format!("{}", startup_commands_start_time.elapsed().as_millis()),
+        startup_commands_start_time
+            .elapsed()
+            .as_millis()
+            .to_string(),
     );
 
     if options.perf {
@@ -235,72 +301,17 @@ pub fn cli(
 
         let cwd = context.shell_manager().path();
 
-        let colored_prompt = {
-            if let Some(prompt) = &prompt {
-                let prompt_line = prompt.as_string()?;
-
-                context.scope.enter_scope();
-                let (prompt_block, err) = nu_parser::parse(&prompt_line, 0, &context.scope);
-
-                if err.is_some() {
-                    context.scope.exit_scope();
-
-                    format!(
-                        "{}{}{}{}{}{}> ",
-                        Color::Green.bold().prefix().to_string(),
-                        cwd,
-                        nu_ansi_term::ansi::RESET,
-                        Color::Cyan.bold().prefix().to_string(),
-                        current_branch(),
-                        nu_ansi_term::ansi::RESET
-                    )
+        // Check if the PROMPT_COMMAND env variable is set. This env variable
+        // contains nu code that is used to overwrite the prompt
+        let colored_prompt = match context.scope.get_env(PROMPT_COMMAND) {
+            Some(env_prompt) => evaluate_prompt_string(&env_prompt, &context, &cwd),
+            None => {
+                if let Some(prompt) = &prompt {
+                    let prompt_line = prompt.as_string()?;
+                    evaluate_prompt_string(&prompt_line, &context, &cwd)
                 } else {
-                    let run_result = run_block(
-                        &prompt_block,
-                        &context,
-                        InputStream::empty(),
-                        ExternalRedirection::Stdout,
-                    );
-                    context.scope.exit_scope();
-
-                    match run_result {
-                        Ok(result) => match result.collect_string(Tag::unknown()) {
-                            Ok(string_result) => {
-                                let errors = context.get_errors();
-                                maybe_print_errors(&context, Text::from(prompt_line));
-                                context.clear_errors();
-
-                                if !errors.is_empty() {
-                                    "> ".to_string()
-                                } else {
-                                    string_result.item
-                                }
-                            }
-                            Err(e) => {
-                                context.host().lock().print_err(e, &Text::from(prompt_line));
-                                context.clear_errors();
-
-                                "> ".to_string()
-                            }
-                        },
-                        Err(e) => {
-                            context.host().lock().print_err(e, &Text::from(prompt_line));
-                            context.clear_errors();
-
-                            "> ".to_string()
-                        }
-                    }
+                    default_prompt_string(&cwd)
                 }
-            } else {
-                format!(
-                    "{}{}{}{}{}{}> ",
-                    Color::Green.bold().prefix().to_string(),
-                    cwd,
-                    nu_ansi_term::ansi::RESET,
-                    Color::Cyan.bold().prefix().to_string(),
-                    current_branch(),
-                    nu_ansi_term::ansi::RESET
-                )
             }
         };
 
@@ -345,7 +356,7 @@ pub fn cli(
         // Store cmd duration in an env var
         context.scope.add_env_var(
             "CMD_DURATION_MS",
-            format!("{}", cmd_start_time.elapsed().as_millis()),
+            cmd_start_time.elapsed().as_millis().to_string(),
         );
 
         match line {
@@ -389,8 +400,7 @@ pub fn cli(
                     .lock()
                     .global_config
                     .as_ref()
-                    .map(|cfg| cfg.var("ctrlc_exit"))
-                    .flatten()
+                    .and_then(|cfg| cfg.var("ctrlc_exit"))
                     .map(|ctrl_c| ctrl_c.is_true())
                     .unwrap_or(false); // default behavior is to allow CTRL-C spamming similar to other shells
 
@@ -432,6 +442,7 @@ pub fn cli(
     Ok(())
 }
 
+#[cfg(feature = "rustyline-support")]
 pub fn load_local_cfg_if_present(context: &EvaluationContext) {
     trace!("Loading local cfg if present");
     match config::loadable_cfg_exists_in_dir(PathBuf::from(context.shell_manager().path())) {

crates/nu-cli/src/keybinding.rs

@@ -461,7 +461,7 @@ pub(crate) fn load_keybindings(
     if let Ok(contents) = contents {
         let keybindings: Keybindings = serde_yaml::from_str(&contents)?;
         // eprintln!("{:#?}", keybindings);
-        for keybinding in keybindings.into_iter() {
+        for keybinding in keybindings {
             let (k, b) = convert_keybinding(keybinding);
             // eprintln!("{:?} {:?}", k, b);
 

crates/nu-cli/src/line_editor.rs

@@ -76,6 +76,8 @@ pub fn default_rustyline_editor_configuration() -> Editor<Helper> {
     let config = Config::builder()
         .check_cursor_position(true)
         .color_mode(ColorMode::Forced)
+        .history_ignore_dups(false)
+        .max_history_size(10_000)
         .build();
     let mut rl: Editor<_> = Editor::with_config(config);
 

crates/nu-command/Cargo.toml

@@ -5,32 +5,35 @@ description = "CLI for nushell"
 edition = "2018"
 license = "MIT"
 name = "nu-command"
-version = "0.35.0"
+version = "0.37.0"
 
 [lib]
 doctest = false
 
 [dependencies]
-nu-data = { version = "0.35.0", path="../nu-data" }
-nu-engine = { version = "0.35.0", path="../nu-engine" }
-nu-errors = { version = "0.35.0", path="../nu-errors" }
-nu-json = { version = "0.35.0", path="../nu-json" }
-nu-path = { version = "0.35.0", path="../nu-path" }
-nu-parser = { version = "0.35.0", path="../nu-parser" }
-nu-plugin = { version = "0.35.0", path="../nu-plugin" }
-nu-protocol = { version = "0.35.0", path="../nu-protocol" }
-nu-source = { version = "0.35.0", path="../nu-source" }
-nu-stream = { version = "0.35.0", path="../nu-stream" }
-nu-table = { version = "0.35.0", path="../nu-table" }
-nu-test-support = { version = "0.35.0", path="../nu-test-support" }
-nu-value-ext = { version = "0.35.0", path="../nu-value-ext" }
-nu-ansi-term = { version = "0.35.0", path="../nu-ansi-term" }
-nu-pretty-hex = { version = "0.35.0", path="../nu-pretty-hex" }
+nu-data = { version = "0.37.0", path="../nu-data" }
+nu-engine = { version = "0.37.0", path="../nu-engine" }
+nu-errors = { version = "0.37.0", path="../nu-errors" }
+nu-json = { version = "0.37.0", path="../nu-json" }
+nu-path = { version = "0.37.0", path="../nu-path" }
+nu-parser = { version = "0.37.0", path="../nu-parser" }
+nu-plugin = { version = "0.37.0", path="../nu-plugin" }
+nu-protocol = { version = "0.37.0", path="../nu-protocol" }
+nu-serde = { version = "0.37.0", path="../nu-serde" }
+nu-source = { version = "0.37.0", path="../nu-source" }
+nu-stream = { version = "0.37.0", path="../nu-stream" }
+nu-table = { version = "0.37.0", path="../nu-table" }
+nu-test-support = { version = "0.37.0", path="../nu-test-support" }
+nu-value-ext = { version = "0.37.0", path="../nu-value-ext" }
+nu-ansi-term = { version = "0.37.0", path="../nu-ansi-term" }
+nu-pretty-hex = { version = "0.37.0", path="../nu-pretty-hex" }
 
+url = "2.2.1"
+mime = "0.3.16"
 Inflector = "0.11"
 arboard = { version="1.1.0", optional=true }
 base64 = "0.13.0"
-bigdecimal = { version="0.2.0", features=["serde"] }
+bigdecimal = { package = "bigdecimal-rs", version = "0.2.1", features = ["serde"] }
 byte-unit = "4.0.9"
 bytes = "1.0.1"
 calamine = "0.18.0"
@@ -44,7 +47,6 @@ derive-new = "0.5.8"
 directories-next = "2.0.0"
 dirs-next = "2.0.0"
 dtparse = "1.2.0"
-dunce = "1.0.1"
 eml-parser = "0.1.0"
 encoding_rs = "0.8.28"
 filesize = "0.2.0"
@@ -71,9 +73,10 @@ quick-xml = "0.22"
 rand = "0.8"
 rayon = "1.5.0"
 regex = "1.4.3"
+reqwest = {version = "0.11", optional = true }
 roxmltree = "0.14.0"
 rust-embed = "5.9.0"
-rustyline = { version="8.1.0", optional=true }
+rustyline = { version="9.0.0", optional=true }
 serde = { version="1.0.123", features=["derive"] }
 serde_bytes = "0.11.5"
 serde_ini = "0.2.0"
@@ -84,24 +87,26 @@ sha2 = "0.9.3"
 strip-ansi-escapes = "0.1.0"
 sxd-document = "0.3.2"
 sxd-xpath = "0.4.2"
+sysinfo = { version = "0.20.2", optional = true }
+thiserror = "1.0.26"
 tempfile = "3.2.0"
 term = { version="0.7.0", optional=true }
 term_size = "0.3.2"
 termcolor = "1.1.2"
 titlecase = "1.1.0"
+tokio = { version = "1", features = ["rt-multi-thread"], optional = true }
 toml = "0.5.8"
 trash = { version="1.3.0", optional=true }
 unicode-segmentation = "1.8"
-url = "2.2.0"
 uuid_crate = { package="uuid", version="0.8.2", features=["v4"], optional=true }
 which = { version="4.1.0", optional=true }
 zip = { version="0.5.9", optional=true }
 digest = "0.9.0"
 
 [dependencies.polars]
-version = "0.14.8"
+version = "0.15.1"
 optional = true
-features = ["parquet", "json", "random", "pivot", "strings", "is_in"]
+features = ["parquet", "json", "random", "pivot", "strings", "is_in", "temporal"]
 
 [target.'cfg(unix)'.dependencies]
 umask = "1.0.0"
@@ -133,3 +138,7 @@ stable = []
 trash-support = ["trash"]
 table-pager = ["minus", "crossterm"]
 dataframe = ["nu-protocol/dataframe", "polars"]
+fetch = ["reqwest", "tokio"]
+post = ["reqwest", "tokio"]
+sys = ["sysinfo"]
+ps = ["sysinfo"]

crates/nu-command/src/classified/external.rs

@@ -4,7 +4,10 @@ use nu_engine::{MaybeTextCodec, StringOrBinary};
 use nu_test_support::NATIVE_PATH_ENV_VAR;
 use parking_lot::Mutex;
 
+#[allow(unused)]
+use std::env;
 use std::io::Write;
+use std::path::PathBuf;
 use std::process::{Command, Stdio};
 use std::sync::mpsc;
 use std::{borrow::Cow, io::BufReader};
@@ -17,6 +20,9 @@ use nu_protocol::hir::{ExternalCommand, ExternalRedirection};
 use nu_protocol::{Primitive, ShellTypeName, UntaggedValue, Value};
 use nu_source::Tag;
 
+#[cfg(feature = "which")]
+use which::which_in;
+
 pub(crate) fn run_external_command(
     command: ExternalCommand,
     context: &mut EvaluationContext,
@@ -104,7 +110,7 @@ fn run_with_stdin(
     let process_args = command_args
         .iter()
         .map(|(arg, _is_literal)| {
-            let arg = nu_path::expand_tilde_string(Cow::Borrowed(arg));
+            let arg = nu_path::expand_tilde(arg).to_string_lossy().to_string();
 
             #[cfg(not(windows))]
             {
@@ -141,6 +147,79 @@ fn run_with_stdin(
     )
 }
 
+/// Spawn a direct exe
+#[allow(unused)]
+fn spawn_exe(full_path: PathBuf, args: &[String]) -> Command {
+    let mut process = Command::new(full_path);
+    for arg in args {
+        process.arg(&arg);
+    }
+    process
+}
+
+/// Spawn a cmd command with `cmd /c args...`
+fn spawn_cmd_command(command: &ExternalCommand, args: &[String]) -> Command {
+    let mut process = Command::new("cmd");
+    process.arg("/c");
+    process.arg(&command.name);
+    for arg in args {
+        // Clean the args before we use them:
+        // https://stackoverflow.com/questions/1200235/how-to-pass-a-quoted-pipe-character-to-cmd-exe
+        // cmd.exe needs to have a caret to escape a pipe
+        let arg = arg.replace("|", "^|");
+        process.arg(&arg);
+    }
+    process
+}
+
+/// Spawn a sh command with `sh -c args...`
+fn spawn_sh_command(command: &ExternalCommand, args: &[String]) -> Command {
+    let cmd_with_args = vec![command.name.clone(), args.join(" ")].join(" ");
+    let mut process = Command::new("sh");
+    process.arg("-c").arg(cmd_with_args);
+    process
+}
+
+/// a function to spawn any external command
+#[allow(unused)] // for minimal builds cwd is unused
+fn spawn_any(command: &ExternalCommand, args: &[String], cwd: &str) -> Command {
+    // resolve the executable name if it is spawnable directly
+    #[cfg(feature = "which")]
+    // TODO add more available paths to `env::var_os("PATH")`?
+    if let Result::Ok(full_path) = which_in(&command.name, env::var_os("PATH"), cwd) {
+        if let Some(extension) = full_path.extension() {
+            #[cfg(windows)]
+            if extension.eq_ignore_ascii_case("exe") {
+                // if exe spawn it directly
+                return spawn_exe(full_path, args);
+            } else {
+                // TODO implement special care for various executable types such as .bat, .ps1, .cmd, etc
+                // https://github.com/mklement0/Native/blob/e0e0b8785cad39a73053e35084d1f60d87fbac58/Native.psm1#L749
+                // otherwise shell out to cmd
+                return spawn_cmd_command(command, args);
+            }
+            #[cfg(not(windows))]
+            if !["sh", "bash"]
+                .iter()
+                .any(|ext| extension.eq_ignore_ascii_case(ext))
+            {
+                // if exe spawn it directly
+                return spawn_exe(full_path, args);
+            } else {
+                // otherwise shell out to sh
+                return spawn_sh_command(command, args);
+            }
+        }
+    }
+    // in all the other cases shell out
+    if cfg!(windows) {
+        spawn_cmd_command(command, args)
+    } else {
+        // TODO what happens if that os doesn't support spawning sh?
+        spawn_sh_command(command, args)
+    }
+}
+
 fn spawn(
     command: &ExternalCommand,
     path: &str,
@@ -151,31 +230,7 @@ fn spawn(
 ) -> Result<InputStream, ShellError> {
     let command = command.clone();
 
-    let mut process = {
-        #[cfg(windows)]
-        {
-            let mut process = Command::new("cmd");
-            process.arg("/c");
-            process.arg(&command.name);
-            for arg in args {
-                // Clean the args before we use them:
-                // https://stackoverflow.com/questions/1200235/how-to-pass-a-quoted-pipe-character-to-cmd-exe
-                // cmd.exe needs to have a caret to escape a pipe
-                let arg = arg.replace("|", "^|");
-                process.arg(&arg);
-            }
-            process
-        }
-
-        #[cfg(not(windows))]
-        {
-            let cmd_with_args = vec![command.name.clone(), args.join(" ")].join(" ");
-            let mut process = Command::new("sh");
-            process.arg("-c").arg(cmd_with_args);
-            process
-        }
-    };
-
+    let mut process = spawn_any(&command, args, path);
     process.current_dir(path);
     trace!(target: "nu::run::external", "cwd = {:?}", &path);
 
@@ -454,7 +509,7 @@ fn spawn(
             Ok(stream.into_input_stream())
         }
         Err(e) => Err(ShellError::labeled_error(
-            format!("{}", e),
+            e.to_string(),
             "failed to spawn",
             &command.name_tag,
         )),

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

@@ -22,6 +22,7 @@ impl WholeStreamCommand for Histogram {
                 None,
             )
             .rest(
+                "rest",
                 SyntaxShape::ColumnPath,
                 "column name to give the histogram's frequency column",
             )

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

@@ -13,6 +13,7 @@ impl WholeStreamCommand for SubCommand {
 
     fn signature(&self) -> Signature {
         Signature::build("into binary").rest(
+            "rest",
             SyntaxShape::ColumnPath,
             "column paths to convert to binary (for table input)",
         )

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

@@ -14,6 +14,7 @@ impl WholeStreamCommand for SubCommand {
 
     fn signature(&self) -> Signature {
         Signature::build("into path").rest(
+            "rest",
             SyntaxShape::ColumnPath,
             "column paths to convert to filepath (for table input)",
         )

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

@@ -0,0 +1,182 @@
+use std::convert::TryInto;
+
+use crate::prelude::*;
+use nu_engine::WholeStreamCommand;
+use nu_errors::ShellError;
+use nu_protocol::{ColumnPath, Primitive, Signature, SyntaxShape, UntaggedValue, Value};
+use num_bigint::ToBigInt;
+
+pub struct SubCommand;
+
+impl WholeStreamCommand for SubCommand {
+    fn name(&self) -> &str {
+        "into filesize"
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("into filesize").rest(
+            "rest",
+            SyntaxShape::ColumnPath,
+            "column paths to convert to filesize (for table input)",
+        )
+    }
+
+    fn usage(&self) -> &str {
+        "Convert value to filesize"
+    }
+
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
+        into_filesize(args)
+    }
+
+    fn examples(&self) -> Vec<Example> {
+        vec![
+            Example {
+                description: "Convert string to filesize in table",
+                example: "echo [[bytes]; ['5'] [3.2] [4] [2kb]] | into filesize bytes",
+                result: Some(vec![
+                    UntaggedValue::row(indexmap! {
+                        "bytes".to_string() => UntaggedValue::filesize(5).into(),
+                    })
+                    .into(),
+                    UntaggedValue::row(indexmap! {
+                        "bytes".to_string() => UntaggedValue::filesize(3).into(),
+                    })
+                    .into(),
+                    UntaggedValue::row(indexmap! {
+                        "bytes".to_string() => UntaggedValue::filesize(4).into(),
+                    })
+                    .into(),
+                    UntaggedValue::row(indexmap! {
+                        "bytes".to_string() => UntaggedValue::filesize(2000).into(),
+                    })
+                    .into(),
+                ]),
+            },
+            Example {
+                description: "Convert string to filesize",
+                example: "echo '2' | into filesize",
+                result: Some(vec![UntaggedValue::filesize(2).into()]),
+            },
+            Example {
+                description: "Convert decimal to filesize",
+                example: "echo 8.3 | into filesize",
+                result: Some(vec![UntaggedValue::filesize(8).into()]),
+            },
+            Example {
+                description: "Convert int to filesize",
+                example: "echo 5 | into filesize",
+                result: Some(vec![UntaggedValue::filesize(5).into()]),
+            },
+            Example {
+                description: "Convert file size to filesize",
+                example: "echo 4KB | into filesize",
+                result: Some(vec![UntaggedValue::filesize(4000).into()]),
+            },
+        ]
+    }
+}
+
+fn into_filesize(args: CommandArgs) -> Result<OutputStream, ShellError> {
+    let column_paths: Vec<ColumnPath> = args.rest(0)?;
+
+    Ok(args
+        .input
+        .map(move |v| {
+            if column_paths.is_empty() {
+                action(&v, v.tag())
+            } else {
+                let mut ret = v;
+                for path in &column_paths {
+                    ret = ret.swap_data_by_column_path(
+                        path,
+                        Box::new(move |old| action(old, old.tag())),
+                    )?;
+                }
+
+                Ok(ret)
+            }
+        })
+        .into_input_stream())
+}
+
+pub fn action(input: &Value, tag: impl Into<Tag>) -> Result<Value, ShellError> {
+    let tag = tag.into();
+    match &input.value {
+        UntaggedValue::Primitive(prim) => Ok(UntaggedValue::filesize(match prim {
+            Primitive::String(a_string) => match int_from_string(a_string.trim(), &tag) {
+                Ok(n) => n,
+                Err(e) => {
+                    return Err(e);
+                }
+            },
+            Primitive::Decimal(dec) => match dec.to_bigint() {
+                Some(n) => match n.to_u64() {
+                    Some(i) => i,
+                    None => {
+                        return Err(ShellError::unimplemented(
+                            "failed to convert decimal to filesize",
+                        ));
+                    }
+                },
+                None => {
+                    return Err(ShellError::unimplemented(
+                        "failed to convert decimal to filesize",
+                    ));
+                }
+            },
+            Primitive::Int(n_ref) => (*n_ref).try_into().map_err(|_| {
+                ShellError::unimplemented("cannot convert negative integer to filesize")
+            })?,
+            Primitive::Filesize(a_filesize) => *a_filesize,
+            _ => {
+                return Err(ShellError::unimplemented(
+                    "'into filesize' for non-numeric primitives",
+                ))
+            }
+        })
+        .into_value(&tag)),
+        UntaggedValue::Row(_) => Err(ShellError::labeled_error(
+            "specify column name to use, with 'into filesize COLUMN'",
+            "found table",
+            tag,
+        )),
+        _ => Err(ShellError::unimplemented(
+            "'into filesize' for unsupported type",
+        )),
+    }
+}
+
+fn int_from_string(a_string: &str, tag: &Tag) -> Result<u64, ShellError> {
+    match a_string.parse::<u64>() {
+        Ok(n) => Ok(n),
+        Err(_) => match a_string.parse::<f64>() {
+            Ok(f) => match f.to_u64() {
+                Some(i) => Ok(i),
+                None => Err(ShellError::labeled_error(
+                    "Could not convert string value to filesize",
+                    "original value",
+                    tag.clone(),
+                )),
+            },
+            Err(_) => Err(ShellError::labeled_error(
+                "Could not convert string value to filesize",
+                "original value",
+                tag.clone(),
+            )),
+        },
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::ShellError;
+    use super::SubCommand;
+
+    #[test]
+    fn examples_work_as_expected() -> Result<(), ShellError> {
+        use crate::examples::test as test_examples;
+
+        test_examples(SubCommand {})
+    }
+}

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

@@ -13,6 +13,7 @@ impl WholeStreamCommand for SubCommand {
 
     fn signature(&self) -> Signature {
         Signature::build("into int").rest(
+            "rest",
             SyntaxShape::ColumnPath,
             "column paths to convert to int (for table input)",
         )

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

@@ -1,9 +1,11 @@
 mod binary;
 mod command;
 mod filepath;
+mod filesize;
 mod int;
 pub mod string;
 
+pub use self::filesize::SubCommand as IntoFilesize;
 pub use binary::SubCommand as IntoBinary;
 pub use command::Command as Into;
 pub use filepath::SubCommand as IntoFilepath;

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

@@ -20,6 +20,7 @@ impl WholeStreamCommand for SubCommand {
     fn signature(&self) -> Signature {
         Signature::build("into string")
             .rest(
+                "rest",
                 SyntaxShape::ColumnPath,
                 "column paths to convert to string (for table input)",
             )
@@ -158,7 +159,7 @@ pub fn action(
 }
 
 fn format_int(int: i64) -> String {
-    format!("{}", int)
+    int.to_string()
 
     // TODO once platform-specific dependencies are stable (see Cargo.toml)
     // #[cfg(windows)]
@@ -175,7 +176,7 @@ fn format_int(int: i64) -> String {
 }
 
 fn format_bigint(int: &BigInt) -> String {
-    format!("{}", int)
+    int.to_string()
 
     // TODO once platform-specific dependencies are stable (see Cargo.toml)
     // #[cfg(windows)]
@@ -229,7 +230,7 @@ fn format_decimal(mut decimal: BigDecimal, digits: Option<u64>, group_digits: bo
     let format_default_loc = |int_part: BigInt| {
         let loc = Locale::en;
         //TODO: when num_format is available for recent bigint, replace this with the locale-based format
-        let (int_str, sep) = (format!("{}", int_part), String::from(loc.decimal()));
+        let (int_str, sep) = (int_part.to_string(), String::from(loc.decimal()));
 
         format!("{}{}{}", int_str, sep, dec_str)
     };

crates/nu-command/src/commands/core_commands/alias.rs

@@ -2,7 +2,7 @@ use crate::prelude::*;
 use nu_engine::WholeStreamCommand;
 
 use nu_errors::ShellError;
-use nu_protocol::{Signature, SyntaxShape};
+use nu_protocol::{Signature, SyntaxShape, UntaggedValue};
 
 pub struct Alias;
 
@@ -15,7 +15,7 @@ impl WholeStreamCommand for Alias {
         Signature::build("alias")
             .required("name", SyntaxShape::String, "the name of the alias")
             .required("equals", SyntaxShape::String, "the equals sign")
-            .rest(SyntaxShape::Any, "the expansion for the alias")
+            .rest("rest", SyntaxShape::Any, "the expansion for the alias")
     }
 
     fn usage(&self) -> &str {
@@ -35,6 +35,18 @@ impl WholeStreamCommand for Alias {
     }
 }
 
-pub fn alias(_: CommandArgs) -> Result<OutputStream, ShellError> {
+pub fn alias(args: CommandArgs) -> Result<OutputStream, ShellError> {
+    // TODO: is there a better way of checking whether no arguments were passed?
+    if args.nth(0).is_none() {
+        let aliases = UntaggedValue::string(
+            &args
+                .scope()
+                .get_aliases()
+                .iter()
+                .map(|val| format!("{} = '{}'", val.0, val.1.iter().map(|x| &x.item).join(" ")))
+                .join("\n"),
+        );
+        return Ok(OutputStream::one(aliases));
+    }
     Ok(OutputStream::empty())
 }

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

@@ -27,7 +27,7 @@ impl WholeStreamCommand for Do {
                 "ignore errors as the block runs",
                 Some('i'),
             )
-            .rest(SyntaxShape::Any, "the parameter(s) for the block")
+            .rest("rest", SyntaxShape::Any, "the parameter(s) for the block")
     }
 
     fn usage(&self) -> &str {

crates/nu-command/src/commands/core_commands/echo.rs

@@ -12,7 +12,7 @@ impl WholeStreamCommand for Echo {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("echo").rest(SyntaxShape::Any, "the values to echo")
+        Signature::build("echo").rest("rest", SyntaxShape::Any, "the values to echo")
     }
 
     fn usage(&self) -> &str {

crates/nu-command/src/commands/core_commands/error/make.rs

@@ -0,0 +1,109 @@
+use crate::prelude::*;
+use nu_engine::WholeStreamCommand;
+use nu_errors::ShellError;
+use nu_protocol::{Primitive, Signature, UntaggedValue, Value};
+
+pub struct SubCommand;
+
+impl WholeStreamCommand for SubCommand {
+    fn name(&self) -> &str {
+        "error make"
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("error make")
+    }
+
+    fn usage(&self) -> &str {
+        "Create an error."
+    }
+
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
+        let input = args.input;
+
+        Ok(input
+            .map(|value| {
+                make_error(&value)
+                    .map(|err| UntaggedValue::Error(err).into_value(value.tag()))
+                    .unwrap_or_else(|| {
+                        UntaggedValue::Error(ShellError::untagged_runtime_error(
+                            "Creating error value not supported.",
+                        ))
+                        .into_value(value.tag())
+                    })
+            })
+            .into_output_stream())
+    }
+
+    fn examples(&self) -> Vec<Example> {
+        vec![Example {
+            description: "Creates a labeled error",
+            example: r#"[
+  [          msg,                 labels,                      span];
+  ["The message", "Helpful message here", ([[start, end]; [0, 141]])]
+] | error make"#,
+            result: None,
+        }]
+    }
+}
+
+fn make_error(value: &Value) -> Option<ShellError> {
+    if let Value {
+        value: UntaggedValue::Row(dict),
+        ..
+    } = value
+    {
+        let msg = dict.get_data_by_key("msg".spanned_unknown());
+
+        let labels =
+            dict.get_data_by_key("labels".spanned_unknown())
+                .and_then(|table| match &table.value {
+                    UntaggedValue::Table(_) => table
+                        .table_entries()
+                        .map(|value| value.as_string().ok())
+                        .collect(),
+                    UntaggedValue::Primitive(Primitive::String(label)) => {
+                        Some(vec![label.to_string()])
+                    }
+                    _ => None,
+                });
+
+        let _anchor = dict.get_data_by_key("tag".spanned_unknown());
+        let span = dict.get_data_by_key("span".spanned_unknown());
+
+        if msg.is_none() || labels.is_none() || span.is_none() {
+            return None;
+        }
+
+        let msg = msg.and_then(|msg| msg.as_string().ok());
+
+        if let Some(labels) = labels {
+            if labels.is_empty() {
+                return None;
+            }
+
+            return Some(ShellError::labeled_error(
+                msg.expect("Message will always be present."),
+                &labels[0],
+                span.map(|data| match data {
+                    Value {
+                        value: UntaggedValue::Row(vals),
+                        ..
+                    } => match (vals.entries.get("start"), vals.entries.get("end")) {
+                        (Some(start), Some(end)) => {
+                            let start = start.as_usize().ok().unwrap_or(0);
+                            let end = end.as_usize().ok().unwrap_or(0);
+
+                            Span::new(start, end)
+                        }
+                        (_, _) => Span::unknown(),
+                    },
+                    _ => Span::unknown(),
+                })
+                .unwrap_or_else(Span::unknown),
+            ));
+        }
+    }
+
+    None
+}

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

@@ -0,0 +1,3 @@
+mod make;
+
+pub use make::SubCommand as ErrorMake;

crates/nu-command/src/commands/core_commands/find.rs

@@ -0,0 +1,110 @@
+use crate::prelude::*;
+use nu_engine::WholeStreamCommand;
+use nu_errors::ShellError;
+use nu_protocol::{Dictionary, Signature, SyntaxShape, UntaggedValue, Value};
+
+pub struct Find;
+
+impl WholeStreamCommand for Find {
+    fn name(&self) -> &str {
+        "find"
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("find").rest("rest", SyntaxShape::String, "search term")
+    }
+
+    fn usage(&self) -> &str {
+        "Find text in the output of a previous command"
+    }
+
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
+        find(args)
+    }
+
+    fn examples(&self) -> Vec<Example> {
+        vec![
+            Example {
+                description: "Search pipeline output for multiple terms",
+                example: r#"ls | find toml md sh"#,
+                result: None,
+            },
+            Example {
+                description: "Search strings for term(s)",
+                example: r#"echo Cargo.toml | find toml"#,
+                result: Some(vec![Value::from("Cargo.toml")]),
+            },
+            Example {
+                description: "Search a number list for term(s)",
+                example: r#"[1 2 3 4 5] | find 5"#,
+                result: Some(vec![UntaggedValue::int(5).into()]),
+            },
+            Example {
+                description: "Search string list for term(s)",
+                example: r#"[moe larry curly] | find l"#,
+                result: Some(vec![Value::from("larry"), Value::from("curly")]),
+            },
+        ]
+    }
+}
+
+fn row_contains(row: &Dictionary, search_terms: Vec<String>) -> bool {
+    for term in search_terms {
+        for (k, v) in &row.entries {
+            let key = k.to_string().trim().to_lowercase();
+            let value = v.convert_to_string().trim().to_lowercase();
+            if key.contains(&term) || value.contains(&term) {
+                return true;
+            }
+        }
+    }
+
+    false
+}
+
+fn find(args: CommandArgs) -> Result<OutputStream, ShellError> {
+    let rest: Vec<Value> = args.rest(0)?;
+
+    Ok(args
+        .input
+        .filter(move |row| match &row.value {
+            UntaggedValue::Row(row) => {
+                let sterms: Vec<String> = rest
+                    .iter()
+                    .map(|t| t.convert_to_string().trim().to_lowercase())
+                    .collect();
+                row_contains(row, sterms)
+            }
+            UntaggedValue::Primitive(_p) => {
+                // eprint!("prim {}", p.type_name());
+                let sterms: Vec<String> = rest
+                    .iter()
+                    .map(|t| t.convert_to_string().trim().to_lowercase())
+                    .collect();
+
+                let prim_string = &row.convert_to_string().trim().to_lowercase();
+                for term in sterms {
+                    if prim_string.contains(&term) {
+                        return true;
+                    }
+                }
+
+                false
+            }
+            _ => false,
+        })
+        .into_output_stream())
+}
+
+#[cfg(test)]
+mod tests {
+    use super::Find;
+    use super::ShellError;
+
+    #[test]
+    fn examples_work_as_expected() -> Result<(), ShellError> {
+        use crate::examples::test as test_examples;
+
+        test_examples(Find {})
+    }
+}

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

@@ -1,14 +1,12 @@
 use crate::prelude::*;
 use crate::TaggedListBuilder;
-use nu_engine::documentation::generate_docs;
-use nu_engine::{Command, WholeStreamCommand};
+use nu_engine::{documentation::generate_docs, Command, WholeStreamCommand};
 use nu_errors::ShellError;
 use nu_protocol::{
-    NamedType, PositionalType, ReturnSuccess, Signature, SyntaxShape, TaggedDictBuilder,
-    UntaggedValue, Value,
+    Dictionary, NamedType, PositionalType, ReturnSuccess, Signature, SyntaxShape,
+    TaggedDictBuilder, UntaggedValue, Value,
 };
-use nu_source::Tag;
-use nu_source::{SpannedItem, Tagged};
+use nu_source::{SpannedItem, Tag, Tagged};
 use nu_value_ext::ValueExt;
 
 pub struct Help;
@@ -19,7 +17,18 @@ impl WholeStreamCommand for Help {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("help").rest(SyntaxShape::String, "the name of command to get help on")
+        Signature::build("help")
+            .rest(
+                "rest",
+                SyntaxShape::String,
+                "the name of command to get help on",
+            )
+            .named(
+                "find",
+                SyntaxShape::String,
+                "string to find in command usage",
+                Some('f'),
+            )
     }
 
     fn usage(&self) -> &str {
@@ -29,14 +38,81 @@ impl WholeStreamCommand for Help {
     fn run_with_actions(&self, args: CommandArgs) -> Result<ActionStream, ShellError> {
         help(args)
     }
+
+    fn examples(&self) -> Vec<Example> {
+        vec![
+            Example {
+                description: "show all commands and sub-commands",
+                example: "help commands",
+                result: None,
+            },
+            Example {
+                description: "generate documentation",
+                example: "help generate_docs",
+                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 usage",
+                example: "help --find char",
+                result: None,
+            },
+        ]
+    }
 }
 
 fn help(args: CommandArgs) -> Result<ActionStream, ShellError> {
     let name = args.call_info.name_tag.clone();
     let scope = args.scope().clone();
-
+    let find: Option<Tagged<String>> = args.get_flag("find")?;
     let rest: Vec<Tagged<String>> = args.rest(0)?;
 
+    if let Some(f) = find {
+        let search_string = f.item;
+        let full_commands = scope.get_commands_info();
+        let mut found_cmds_vec = Vec::new();
+
+        for (key, cmd) in full_commands {
+            let mut indexmap = IndexMap::new();
+
+            let c = cmd.usage().to_string();
+            let e = cmd.extra_usage().to_string();
+            if key.to_lowercase().contains(&search_string)
+                || c.to_lowercase().contains(&search_string)
+                || e.to_lowercase().contains(&search_string)
+            {
+                indexmap.insert(
+                    "name".to_string(),
+                    UntaggedValue::string(key).into_value(&name),
+                );
+
+                indexmap.insert(
+                    "usage".to_string(),
+                    UntaggedValue::string(cmd.usage().to_string()).into_value(&name),
+                );
+
+                indexmap.insert(
+                    "extra_usage".to_string(),
+                    UntaggedValue::string(cmd.extra_usage().to_string()).into_value(&name),
+                );
+
+                found_cmds_vec
+                    .push(UntaggedValue::Row(Dictionary::from(indexmap)).into_value(&name));
+            }
+        }
+
+        return Ok(found_cmds_vec.into_iter().into_action_stream());
+    }
+
     if !rest.is_empty() {
         if rest[0].item == "commands" {
             let mut sorted_names = scope.get_command_names();
@@ -226,7 +302,7 @@ pub fn signature_dict(signature: Signature, tag: impl Into<Tag>) -> Value {
     let tag = tag.into();
     let mut sig = TaggedListBuilder::new(&tag);
 
-    for arg in signature.positional.iter() {
+    for arg in &signature.positional {
         let is_required = matches!(arg.0, PositionalType::Mandatory(_, _));
 
         sig.push_value(for_spec(arg.0.name(), "argument", is_required, &tag));
@@ -237,7 +313,7 @@ pub fn signature_dict(signature: Signature, tag: impl Into<Tag>) -> Value {
         sig.push_value(for_spec("rest", "argument", is_required, &tag));
     }
 
-    for (name, ty) in signature.named.iter() {
+    for (name, ty) in &signature.named {
         match ty.0 {
             NamedType::Mandatory(_, _) => sig.push_value(for_spec(name, "flag", true, &tag)),
             NamedType::Optional(_, _) => sig.push_value(for_spec(name, "flag", false, &tag)),

crates/nu-command/src/commands/core_commands/if_.rs

@@ -100,14 +100,14 @@ fn if_command(args: CommandArgs) -> Result<OutputStream, ShellError> {
     context.scope.add_vars(&condition.captured.entries);
 
     //FIXME: should we use the scope that's brought in as well?
-    let condition = evaluate_baseline_expr(cond, &*context);
+    let condition = evaluate_baseline_expr(cond, &context);
     match condition {
         Ok(condition) => match condition.as_bool() {
             Ok(b) => {
                 let result = if b {
-                    run_block(&then_case.block, &*context, input, external_redirection)
+                    run_block(&then_case.block, &context, input, external_redirection)
                 } else {
-                    run_block(&else_case.block, &*context, input, external_redirection)
+                    run_block(&else_case.block, &context, input, external_redirection)
                 };
                 context.scope.exit_scope();
 

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

@@ -4,6 +4,8 @@ mod def;
 mod describe;
 mod do_;
 pub(crate) mod echo;
+mod error;
+mod find;
 mod help;
 mod history;
 mod if_;
@@ -13,6 +15,8 @@ mod nu_plugin;
 mod nu_signature;
 mod source;
 mod tags;
+mod tutor;
+mod unalias;
 mod version;
 
 pub use self::nu_plugin::SubCommand as NuPlugin;
@@ -25,6 +29,8 @@ pub use def::Def;
 pub use describe::Describe;
 pub use do_::Do;
 pub use echo::Echo;
+pub use error::*;
+pub use find::Find;
 pub use help::Help;
 pub use history::History;
 pub use if_::If;
@@ -32,4 +38,6 @@ pub use ignore::Ignore;
 pub use let_::Let;
 pub use source::Source;
 pub use tags::Tags;
+pub use tutor::Tutor;
+pub use unalias::Unalias;
 pub use version::{version, Version};

crates/nu-command/src/commands/core_commands/nu_plugin.rs

@@ -4,7 +4,7 @@ use crate::prelude::*;
 use nu_engine::WholeStreamCommand;
 
 use nu_errors::ShellError;
-use nu_path::canonicalize;
+use nu_path::canonicalize_with;
 use nu_protocol::{CommandAction, ReturnSuccess, Signature, SyntaxShape, UntaggedValue};
 use nu_source::Tagged;
 
@@ -56,7 +56,7 @@ impl WholeStreamCommand for SubCommand {
             tag,
         }) = load_path
         {
-            let path = canonicalize(shell_manager.path(), load_path).map_err(|_| {
+            let path = canonicalize_with(load_path, shell_manager.path()).map_err(|_| {
                 ShellError::labeled_error(
                     "Cannot load plugins from directory",
                     "directory not found",

crates/nu-command/src/commands/core_commands/nu_signature.rs

@@ -41,7 +41,7 @@ impl WholeStreamCommand for Command {
                 "custom configuration source file",
                 None,
             )
-            .rest(SyntaxShape::String, "source file(s) to run")
+            .rest("rest", SyntaxShape::String, "source file(s) to run")
     }
 
     fn usage(&self) -> &str {

crates/nu-command/src/commands/core_commands/source.rs

@@ -2,11 +2,11 @@ use crate::prelude::*;
 use nu_engine::{script, WholeStreamCommand};
 
 use nu_errors::ShellError;
-use nu_path::expand_path;
+use nu_path::{canonicalize, canonicalize_with};
 use nu_protocol::{Signature, SyntaxShape};
 use nu_source::Tagged;
 
-use std::{borrow::Cow, path::Path};
+use std::path::Path;
 
 pub struct Source;
 
@@ -32,7 +32,7 @@ impl WholeStreamCommand for Source {
         "Runs a script file in the current context."
     }
 
-    fn run_with_actions(&self, args: CommandArgs) -> Result<ActionStream, ShellError> {
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
         source(args)
     }
 
@@ -41,14 +41,68 @@ impl WholeStreamCommand for Source {
     }
 }
 
-pub fn source(args: CommandArgs) -> Result<ActionStream, ShellError> {
+pub fn source(args: CommandArgs) -> Result<OutputStream, ShellError> {
     let ctx = &args.context;
     let filename: Tagged<String> = args.req(0)?;
 
+    let source_file = Path::new(&filename.item);
+
     // Note: this is a special case for setting the context from a command
     // In this case, if we don't set it now, we'll lose the scope that this
     // variable should be set into.
-    let contents = std::fs::read_to_string(&expand_path(Cow::Borrowed(Path::new(&filename.item))));
+
+    let lib_dirs = &ctx
+        .configs()
+        .lock()
+        .global_config
+        .as_ref()
+        .map(|configuration| match configuration.var("lib_dirs") {
+            Some(paths) => paths
+                .table_entries()
+                .cloned()
+                .map(|path| path.as_string())
+                .collect(),
+            None => vec![],
+        });
+
+    if let Some(dir) = lib_dirs {
+        for lib_path in dir {
+            match lib_path {
+                Ok(name) => {
+                    let path = canonicalize_with(&source_file, name).map_err(|e| {
+                        ShellError::labeled_error(
+                            format!("Can't load source file. Reason: {}", e.to_string()),
+                            "Can't load this file",
+                            filename.span(),
+                        )
+                    })?;
+
+                    if let Ok(contents) = std::fs::read_to_string(path) {
+                        let result = script::run_script_standalone(contents, true, ctx, false);
+
+                        if let Err(err) = result {
+                            ctx.error(err);
+                        }
+                        return Ok(OutputStream::empty());
+                    }
+                }
+                Err(reason) => {
+                    ctx.error(reason.clone());
+                }
+            }
+        }
+    }
+
+    let path = canonicalize(source_file).map_err(|e| {
+        ShellError::labeled_error(
+            format!("Can't load source file. Reason: {}", e.to_string()),
+            "Can't load this file",
+            filename.span(),
+        )
+    })?;
+
+    let contents = std::fs::read_to_string(path);
+
     match contents {
         Ok(contents) => {
             let result = script::run_script_standalone(contents, true, ctx, false);
@@ -56,16 +110,16 @@ pub fn source(args: CommandArgs) -> Result<ActionStream, ShellError> {
             if let Err(err) = result {
                 ctx.error(err);
             }
-            Ok(ActionStream::empty())
+            Ok(OutputStream::empty())
         }
-        Err(_) => {
+        Err(e) => {
             ctx.error(ShellError::labeled_error(
-                "Can't load file to source",
-                "can't load file",
+                format!("Can't load source file. Reason: {}", e.to_string()),
+                "Can't load this file",
                 filename.span(),
             ));
 
-            Ok(ActionStream::empty())
+            Ok(OutputStream::empty())
         }
     }
 }

crates/nu-command/src/commands/core_commands/tags.rs

@@ -1,7 +1,7 @@
 use crate::prelude::*;
 use nu_engine::WholeStreamCommand;
 use nu_errors::ShellError;
-use nu_protocol::{Signature, TaggedDictBuilder, UntaggedValue};
+use nu_protocol::{Primitive, Signature, TaggedDictBuilder, UntaggedValue, Value};
 
 pub struct Tags;
 
@@ -18,37 +18,64 @@ impl WholeStreamCommand for Tags {
         "Read the tags (metadata) for values."
     }
 
-    fn run_with_actions(&self, args: CommandArgs) -> Result<ActionStream, ShellError> {
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
         Ok(tags(args))
     }
 }
 
-fn tags(args: CommandArgs) -> ActionStream {
-    args.input
-        .map(move |v| {
-            let mut tags = TaggedDictBuilder::new(v.tag());
-            {
-                let anchor = v.anchor();
-                let span = v.tag.span;
-                let mut dict = TaggedDictBuilder::new(v.tag());
-                dict.insert_untagged("start", UntaggedValue::int(span.start() as i64));
-                dict.insert_untagged("end", UntaggedValue::int(span.end() as i64));
-                tags.insert_value("span", dict.into_value());
+fn build_tag_table(tag: impl Into<Tag>) -> Value {
+    let tag = tag.into();
+    let span = tag.span;
 
-                match anchor {
-                    Some(AnchorLocation::File(source)) => {
-                        tags.insert_untagged("anchor", UntaggedValue::string(source));
-                    }
-                    Some(AnchorLocation::Url(source)) => {
-                        tags.insert_untagged("anchor", UntaggedValue::string(source));
-                    }
-                    _ => {}
-                }
+    TaggedDictBuilder::build(tag.clone(), |tags| {
+        if let Some(anchor) = anchor_as_value(&tag) {
+            tags.insert_value("anchor", anchor);
+        }
+
+        tags.insert_value(
+            "span",
+            TaggedDictBuilder::build(tag.clone(), |span_dict| {
+                span_dict.insert_untagged("start", UntaggedValue::int(span.start() as i64));
+                span_dict.insert_untagged("end", UntaggedValue::int(span.end() as i64));
+            }),
+        );
+    })
+}
+
+fn tags(args: CommandArgs) -> OutputStream {
+    if args.input.is_empty() {
+        OutputStream::one(build_tag_table(&args.name_tag()))
+    } else {
+        args.input
+            .map(move |v| build_tag_table(v.tag()))
+            .into_output_stream()
+    }
+}
+
+fn anchor_as_value(tag: &Tag) -> Option<Value> {
+    let anchor = tag.anchor.as_ref();
+
+    anchor.as_ref()?;
+
+    Some(TaggedDictBuilder::build(tag, |table| {
+        let value = match anchor {
+            Some(AnchorLocation::File(path)) => {
+                Some(("file", UntaggedValue::from(path.to_string())))
             }
+            Some(AnchorLocation::Url(destination)) => {
+                Some(("url", UntaggedValue::from(destination.to_string())))
+            }
+            Some(AnchorLocation::Source(text)) => Some((
+                "source",
+                UntaggedValue::Primitive(Primitive::String(text.to_string())),
+            )),
+            None => None,
+        };
 
-            tags.into_value()
-        })
-        .into_action_stream()
+        if let Some((key, value)) = value {
+            table.insert_untagged(key, value);
+        }
+    }))
 }
 
 #[cfg(test)]

crates/nu-command/src/commands/core_commands/tutor.rs

@@ -0,0 +1,407 @@
+use crate::prelude::*;
+use nu_engine::WholeStreamCommand;
+use nu_errors::ShellError;
+use nu_protocol::{Signature, SyntaxShape, UntaggedValue};
+
+pub struct Tutor;
+
+impl WholeStreamCommand for Tutor {
+    fn name(&self) -> &str {
+        "tutor"
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("tutor")
+            .optional(
+                "search",
+                SyntaxShape::String,
+                "item to search for, or 'list' to list available tutorials",
+            )
+            .named(
+                "find",
+                SyntaxShape::String,
+                "Search tutorial for a phrase",
+                Some('f'),
+            )
+    }
+
+    fn usage(&self) -> &str {
+        "Run the tutorial. To begin, run: tutor"
+    }
+
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
+        tutor(args)
+    }
+
+    fn examples(&self) -> Vec<Example> {
+        vec![
+            Example {
+                description: "Begin the tutorial",
+                example: "tutor begin",
+                result: None,
+            },
+            Example {
+                description: "Search a tutorial by phrase",
+                example: "tutor -f \"$in\"",
+                result: None,
+            },
+        ]
+    }
+}
+
+fn tutor(args: CommandArgs) -> Result<OutputStream, ShellError> {
+    let tag = args.name_tag();
+    let scope = args.scope().clone();
+
+    let search: Option<String> = args.opt(0).unwrap_or(None);
+    let find: Option<String> = args.get_flag("find")?;
+
+    let search_space = [
+        (vec!["begin"], begin_tutor()),
+        (
+            vec!["table", "tables", "row", "rows", "column", "columns"],
+            table_tutor(),
+        ),
+        (vec!["cell", "cells"], cell_tutor()),
+        (
+            vec![
+                "expr",
+                "exprs",
+                "expressions",
+                "subexpression",
+                "subexpressions",
+                "sub-expression",
+                "sub-expressions",
+            ],
+            expression_tutor(),
+        ),
+        (vec!["echo"], echo_tutor()),
+        (vec!["each", "iteration", "iter"], each_tutor()),
+        (
+            vec!["var", "vars", "variable", "variables"],
+            variable_tutor(),
+        ),
+        (vec!["block", "blocks"], block_tutor()),
+        (vec!["shorthand", "shorthands"], shorthand_tutor()),
+    ];
+
+    if let Some(find) = find {
+        let mut results = vec![];
+        for search_group in search_space {
+            if search_group.1.contains(&find) {
+                results.push(search_group.0[0].to_string())
+            }
+        }
+
+        let message = format!("You can find '{}' in the following topics:\n{}\n\nYou can learn about a topic using `tutor` followed by the name of the topic.\nFor example: `tutor table` to open the table topic.\n\n",
+            find,
+            results.into_iter().map(|x| format!("- {}", x)).join("\n")
+        );
+
+        return Ok(display(tag, &scope, &message));
+    } else if let Some(search) = search {
+        for search_group in search_space {
+            if search_group.0.contains(&search.as_str()) {
+                return Ok(display(tag, &scope, search_group.1));
+            }
+        }
+    }
+    Ok(display(tag, &scope, default_tutor()))
+}
+
+fn default_tutor() -> &'static str {
+    r#"
+Welcome to the Nushell tutorial!
+
+With the `tutor` command, you'll be able to learn a lot about how Nushell
+works along with many fun tips and tricks to speed up everyday tasks.
+
+To get started, you can use `tutor begin`.
+
+"#
+}
+
+fn begin_tutor() -> &'static str {
+    r#"
+Nushell is a structured shell and programming language. One way to begin
+using it is to try a few of the commands.
+
+The first command to try is `ls`. The `ls` command will show you a list
+of the files in the current directory. Notice that these files are shown
+as a table. Each column of this table not only tells us what is being
+shown, but also gives us a way to work with the data.
+
+You can combine the `ls` command with other commands using the pipeline
+symbol '|'. This allows data to flow from one command to the next.
+
+For example, if we only wanted the name column, we could do:
+```
+ls | select name
+```
+Notice that we still get a table, but this time it only has one column:
+the name column.
+
+You can continue to learn more about tables by running:
+```
+tutor tables
+```
+If at any point, you'd like to restart this tutorial, you can run:
+```
+tutor begin
+```
+"#
+}
+
+fn table_tutor() -> &'static str {
+    r#"
+The most common form of data in Nushell is the table. Tables contain rows and
+columns of data. In each cell of the table, there is data that you can access
+using Nushell commands.
+
+To get the 3rd row in the table, you can use the `nth` command:
+```
+ls | nth 2
+```
+This will get the 3rd (note that `nth` is zero-based) row in the table created
+by the `ls` command. You can use `nth` on any table created by other commands
+as well.
+
+You can also access the column of data in one of two ways. If you want to want
+to keep the column as part of a new table, you can use `select`.
+```
+ls | select name
+```
+This runs `ls` and returns only the "name" column of the table.
+
+If, instead, you'd like to get access to the values inside of the column, you
+can use the `get` command.
+```
+ls | get name
+```
+This allows us to get to the list of strings that are the filenames rather
+than having a full table. In some cases, this can make the names easier to 
+work with.
+
+You can continue to learn more about working with cells of the table by
+running:
+```
+tutor cells
+```
+"#
+}
+
+fn cell_tutor() -> &'static str {
+    r#"
+Working with cells of data in the table is a key part of working with data in
+Nushell. Because of this, there is a rich list of commands to work with cells
+as well as handy shorthands for accessing cells.
+
+Cells can hold simple values like strings and numbers, or more complex values
+like lists and tables.
+
+To reach a cell of data from a table, you can combine a row operation and a
+column operation.
+```
+ls | nth 4 | get name
+```
+You can combine these operations into one step using a shortcut.
+```
+(ls).4.name
+```
+Names/strings represent columns names and numbers represent row numbers.
+
+The `(ls)` is a form of expression. You can continue to learn more about
+expressions by running:
+```
+tutor expressions
+```
+You can also learn about these cell shorthands by running:
+```
+tutor shorthands
+```
+"#
+}
+
+fn expression_tutor() -> &'static str {
+    r#"
+Expressions give you the power to mix calls to commands with math. The
+simplest expression is a single value like a string or number.
+```
+3
+```
+Expressions can also include math operations like addition or division.
+```
+10 / 2
+```
+Normally, an expression is one type of operation: math or commands. You can
+mix these types by using subexpressions. Subexpressions are just like
+expressions, but they're wrapped in parentheses `()`.
+```
+10 * (3 + 4)
+```
+Here we use parentheses to create a higher math precedence in the math 
+expression.
+```
+echo (2 + 3)
+```
+You can continue to learn more about the `echo` command by running:
+```
+tutor echo
+```
+"#
+}
+
+fn echo_tutor() -> &'static str {
+    r#"
+The `echo` command in Nushell is a powerful tool for not only seeing values,
+but also for creating new ones.
+```
+echo "Hello"
+```
+You can echo output. This output, if it's not redirected using a "|" pipeline
+will be displayed to the screen.
+```
+echo 1..10
+```
+You can also use echo to work with individual values of a range. In this
+example, `echo` will create the values from 1 to 10 as a list.
+```
+echo 1 2 3 4 5
+```
+You can also create lists of values by passing `echo` multiple arguments.
+This can be helpful if you want to later processes these values.
+
+The `echo` command can pair well with the `each` command which can run
+code on each row, or item, of input.
+
+You can continue to learn more about the `echo` command by running:
+```
+tutor each
+```
+"#
+}
+
+fn each_tutor() -> &'static str {
+    r#"
+The `each` command gives us a way of working with each individual row or
+element of a list one at a time. It reads these in from the pipeline and
+runs a block on each element. A block is a group of pipelines.
+```
+echo 1 2 3 | each { $it + 10}
+```
+This example iterates over each element sent by `echo`, giving us three new
+values that are the original value + 10. Here, the `$it` is a variable that
+is the name given to the block's parameter by default.
+
+You can learn more about blocks by running:
+```
+tutor blocks
+```
+You can also learn more about variables by running:
+```
+tutor variables
+```
+"#
+}
+
+fn variable_tutor() -> &'static str {
+    r#"
+Variables are an important way to store values to be used later. To create a
+variable, you can use the `let` keyword. The `let` command will create a
+variable and then assign it a value in one step.
+```
+let $x = 3
+```
+Once created, we can refer to this variable by name.
+```
+$x
+```
+Nushell also comes with built-in variables. The `$nu` variable is a reserved
+variable that contains a lot of information about the currently running
+instance of Nushell. The `$it` variable is the name given to block parameters
+if you don't specify one. And `$in` is the variable that allows you to work
+with all of the data coming in from the pipeline in one place.
+
+"#
+}
+
+fn block_tutor() -> &'static str {
+    r#"
+Blocks are a special form of expression that hold code to be run at a later
+time. Often, you'll see blocks as one of the arguments given to commands
+like `each` and `if`.
+```
+ls | each {|x| $x.name}
+```
+The above will create a list of the filenames in the directory.
+```
+if $true { echo "it's true" } { echo "it's not true" }
+```
+This `if` call will run the first block if the expression is true, or the
+second block if the expression is false.
+
+"#
+}
+
+fn shorthand_tutor() -> &'static str {
+    r#"
+You can access cells in a table using a shorthand notation sometimes called a
+"column path" or "cell path". These paths allow you to go from a table to
+rows, columns, or cells inside of the table.
+
+Shorthand paths are made from rows numbers, column names, or both. You can use
+them on any variable or subexpression.
+```
+$nu.cwd
+```
+The above accesses the built-in `$nu` variable, gets its table, and then uses
+the shorthand path to retrieve only the cell data inside the "cwd" column.
+```
+(ls).name.4
+```
+This will retrieve the cell data in the "name" column on the 5th row (note: 
+row numbers are zero-based).
+
+Rows and columns don't need to come in any specific order. You can get the
+same value using:
+```
+(ls).4.name
+```
+"#
+}
+
+fn display(tag: Tag, scope: &Scope, help: &str) -> OutputStream {
+    let help = help.split('`');
+
+    let mut build = String::new();
+    let mut code_mode = false;
+    let palette = nu_engine::DefaultPalette {};
+
+    for item in help {
+        if code_mode {
+            code_mode = false;
+
+            //TODO: support no-color mode
+            let colored_example = nu_engine::Painter::paint_string(item, scope, &palette);
+            build.push_str(&colored_example);
+        } else {
+            code_mode = true;
+            build.push_str(item);
+        }
+    }
+
+    OutputStream::one(UntaggedValue::string(build).into_value(tag))
+}
+
+#[cfg(test)]
+mod tests {
+    use super::ShellError;
+    use super::Tutor;
+
+    #[test]
+    fn examples_work_as_expected() -> Result<(), ShellError> {
+        use crate::examples::test as test_examples;
+
+        test_examples(Tutor {})
+    }
+}

crates/nu-command/src/commands/core_commands/unalias.rs

@@ -0,0 +1,37 @@
+use crate::prelude::*;
+use nu_engine::WholeStreamCommand;
+
+use nu_errors::ShellError;
+use nu_protocol::{Signature, SyntaxShape};
+
+pub struct Unalias;
+
+impl WholeStreamCommand for Unalias {
+    fn name(&self) -> &str {
+        "unalias"
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("unalias").required("name", SyntaxShape::String, "the name of the alias")
+    }
+
+    fn usage(&self) -> &str {
+        "Removes an alias"
+    }
+
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
+        unalias(args)
+    }
+
+    fn examples(&self) -> Vec<Example> {
+        vec![Example {
+            description: "Remove the 'v' alias",
+            example: "unalias v",
+            result: None,
+        }]
+    }
+}
+
+pub fn unalias(_: CommandArgs) -> Result<OutputStream, ShellError> {
+    Ok(OutputStream::empty())
+}

crates/nu-command/src/commands/dataframe/aggregate.rs

@@ -245,7 +245,7 @@ fn perform_groupby_aggregation(
                 None => &col[..],
             };
 
-            res.rename(col.as_str(), new_col)
+            res.rename(&col, new_col)
                 .expect("Column is always there. Looping with known names");
         }
     }

crates/nu-command/src/commands/dataframe/append.rs

@@ -107,7 +107,7 @@ fn command(mut args: CommandArgs) -> Result<OutputStream, ShellError> {
     let other: Value = args.req_named("other")?;
     let axis: Tagged<String> = args.req_named("axis")?;
 
-    let axis = Axis::try_from_str(axis.item.as_str(), &axis.tag.span)?;
+    let axis = Axis::try_from_str(&axis.item, &axis.tag.span)?;
 
     let df_other = match other.value {
         UntaggedValue::DataFrame(df) => Ok(df),

crates/nu-command/src/commands/dataframe/column.rs

@@ -53,7 +53,7 @@ fn command(mut args: CommandArgs) -> Result<OutputStream, ShellError> {
 
     let res = df
         .as_ref()
-        .column(column.item.as_ref())
+        .column(&column.item)
         .map_err(|e| parse_polars_error::<&str>(&e, &column.tag.span, None))?;
 
     let df = NuDataFrame::try_from_series(vec![res.clone()], &tag.span)?;

crates/nu-command/src/commands/dataframe/describe.rs

@@ -0,0 +1,232 @@
+use crate::prelude::*;
+use nu_engine::WholeStreamCommand;
+use nu_errors::ShellError;
+use nu_protocol::{
+    dataframe::{Column, NuDataFrame},
+    Signature, UntaggedValue,
+};
+use polars::{
+    chunked_array::ChunkedArray,
+    prelude::{
+        AnyValue, DataFrame as PolarsDF, DataType, Float64Type, IntoSeries, NewChunkedArray,
+        Series, Utf8Type,
+    },
+};
+
+use super::utils::parse_polars_error;
+
+pub struct DataFrame;
+
+impl WholeStreamCommand for DataFrame {
+    fn name(&self) -> &str {
+        "dataframe describe"
+    }
+
+    fn usage(&self) -> &str {
+        "[DataFrame] Describes dataframes numeric columns"
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("dataframe describe")
+    }
+
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
+        command(args)
+    }
+
+    fn examples(&self) -> Vec<Example> {
+        vec![Example {
+            description: "Describes dataframe",
+            example: "[[a b]; [1 1] [1 1]] | dataframe to-df | dataframe describe",
+            result: Some(vec![NuDataFrame::try_from_columns(
+                vec![
+                    Column::new(
+                        "descriptor".to_string(),
+                        vec![
+                            UntaggedValue::string("count").into(),
+                            UntaggedValue::string("sum").into(),
+                            UntaggedValue::string("mean").into(),
+                            UntaggedValue::string("median").into(),
+                            UntaggedValue::string("std").into(),
+                            UntaggedValue::string("min").into(),
+                            UntaggedValue::string("25%").into(),
+                            UntaggedValue::string("50%").into(),
+                            UntaggedValue::string("75%").into(),
+                            UntaggedValue::string("max").into(),
+                        ],
+                    ),
+                    Column::new(
+                        "a (i64)".to_string(),
+                        vec![
+                            UntaggedValue::decimal_from_float(2.0, Span::default()).into(),
+                            UntaggedValue::decimal_from_float(2.0, Span::default()).into(),
+                            UntaggedValue::decimal_from_float(1.0, Span::default()).into(),
+                            UntaggedValue::decimal_from_float(1.0, Span::default()).into(),
+                            UntaggedValue::decimal_from_float(0.0, Span::default()).into(),
+                            UntaggedValue::decimal_from_float(1.0, Span::default()).into(),
+                            UntaggedValue::decimal_from_float(1.0, Span::default()).into(),
+                            UntaggedValue::decimal_from_float(1.0, Span::default()).into(),
+                            UntaggedValue::decimal_from_float(1.0, Span::default()).into(),
+                            UntaggedValue::decimal_from_float(1.0, Span::default()).into(),
+                        ],
+                    ),
+                    Column::new(
+                        "b (i64)".to_string(),
+                        vec![
+                            UntaggedValue::decimal_from_float(2.0, Span::default()).into(),
+                            UntaggedValue::decimal_from_float(2.0, Span::default()).into(),
+                            UntaggedValue::decimal_from_float(1.0, Span::default()).into(),
+                            UntaggedValue::decimal_from_float(1.0, Span::default()).into(),
+                            UntaggedValue::decimal_from_float(0.0, Span::default()).into(),
+                            UntaggedValue::decimal_from_float(1.0, Span::default()).into(),
+                            UntaggedValue::decimal_from_float(1.0, Span::default()).into(),
+                            UntaggedValue::decimal_from_float(1.0, Span::default()).into(),
+                            UntaggedValue::decimal_from_float(1.0, Span::default()).into(),
+                            UntaggedValue::decimal_from_float(1.0, Span::default()).into(),
+                        ],
+                    ),
+                ],
+                &Span::default(),
+            )
+            .expect("simple df for test should not fail")
+            .into_value(Tag::default())]),
+        }]
+    }
+}
+
+fn command(mut args: CommandArgs) -> Result<OutputStream, ShellError> {
+    let tag = args.call_info.name_tag.clone();
+
+    let (df, _) = NuDataFrame::try_from_stream(&mut args.input, &tag.span)?;
+
+    let names = ChunkedArray::<Utf8Type>::new_from_opt_slice(
+        "descriptor",
+        &[
+            Some("count"),
+            Some("sum"),
+            Some("mean"),
+            Some("median"),
+            Some("std"),
+            Some("min"),
+            Some("25%"),
+            Some("50%"),
+            Some("75%"),
+            Some("max"),
+        ],
+    )
+    .into_series();
+
+    let head = std::iter::once(names);
+
+    let tail = df.as_ref().get_columns().iter().map(|col| {
+        let count = col.len() as f64;
+
+        let sum = match col.sum_as_series().cast_with_dtype(&DataType::Float64) {
+            Ok(ca) => match ca.get(0) {
+                AnyValue::Float64(v) => Some(v),
+                _ => None,
+            },
+            Err(_) => None,
+        };
+
+        let mean = match col.mean_as_series().get(0) {
+            AnyValue::Float64(v) => Some(v),
+            _ => None,
+        };
+
+        let median = match col.median_as_series().get(0) {
+            AnyValue::Float64(v) => Some(v),
+            _ => None,
+        };
+
+        let std = match col.std_as_series().get(0) {
+            AnyValue::Float64(v) => Some(v),
+            _ => None,
+        };
+
+        let min = match col.min_as_series().cast_with_dtype(&DataType::Float64) {
+            Ok(ca) => match ca.get(0) {
+                AnyValue::Float64(v) => Some(v),
+                _ => None,
+            },
+            Err(_) => None,
+        };
+
+        let q_25 = match col.quantile_as_series(0.25) {
+            Ok(ca) => match ca.cast_with_dtype(&DataType::Float64) {
+                Ok(ca) => match ca.get(0) {
+                    AnyValue::Float64(v) => Some(v),
+                    _ => None,
+                },
+                Err(_) => None,
+            },
+            Err(_) => None,
+        };
+
+        let q_50 = match col.quantile_as_series(0.50) {
+            Ok(ca) => match ca.cast_with_dtype(&DataType::Float64) {
+                Ok(ca) => match ca.get(0) {
+                    AnyValue::Float64(v) => Some(v),
+                    _ => None,
+                },
+                Err(_) => None,
+            },
+            Err(_) => None,
+        };
+
+        let q_75 = match col.quantile_as_series(0.75) {
+            Ok(ca) => match ca.cast_with_dtype(&DataType::Float64) {
+                Ok(ca) => match ca.get(0) {
+                    AnyValue::Float64(v) => Some(v),
+                    _ => None,
+                },
+                Err(_) => None,
+            },
+            Err(_) => None,
+        };
+
+        let max = match col.max_as_series().cast_with_dtype(&DataType::Float64) {
+            Ok(ca) => match ca.get(0) {
+                AnyValue::Float64(v) => Some(v),
+                _ => None,
+            },
+            Err(_) => None,
+        };
+
+        let name = format!("{} ({})", col.name(), col.dtype());
+        ChunkedArray::<Float64Type>::new_from_opt_slice(
+            &name,
+            &[
+                Some(count),
+                sum,
+                mean,
+                median,
+                std,
+                min,
+                q_25,
+                q_50,
+                q_75,
+                max,
+            ],
+        )
+        .into_series()
+    });
+
+    let res = head.chain(tail).collect::<Vec<Series>>();
+    let df = PolarsDF::new(res).map_err(|e| parse_polars_error::<&str>(&e, &tag.span, None))?;
+    let df = NuDataFrame::dataframe_to_value(df, tag);
+    Ok(OutputStream::one(df))
+}
+
+#[cfg(test)]
+mod tests {
+    use super::DataFrame;
+    use super::ShellError;
+
+    #[test]
+    fn examples_work_as_expected() -> Result<(), ShellError> {
+        use crate::examples::test_dataframe as test_examples;
+
+        test_examples(DataFrame {})
+    }
+}

crates/nu-command/src/commands/dataframe/drop.rs

@@ -20,7 +20,11 @@ impl WholeStreamCommand for DataFrame {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("dataframe drop").rest(SyntaxShape::Any, "column names to be dropped")
+        Signature::build("dataframe drop").rest(
+            "rest",
+            SyntaxShape::Any,
+            "column names to be dropped",
+        )
     }
 
     fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {

crates/nu-command/src/commands/dataframe/dtypes.rs

@@ -72,7 +72,7 @@ fn command(mut args: CommandArgs) -> Result<OutputStream, ShellError> {
                 .expect("using name from list of names from dataframe")
                 .dtype();
 
-            let dtype_str = format!("{}", dtype);
+            let dtype_str = dtype.to_string();
             dtypes.push(Value {
                 value: dtype_str.into(),
                 tag: Tag::default(),

crates/nu-command/src/commands/dataframe/get.rs

@@ -19,7 +19,11 @@ impl WholeStreamCommand for DataFrame {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("dataframe get").rest(SyntaxShape::Any, "column names to sort dataframe")
+        Signature::build("dataframe get").rest(
+            "rest",
+            SyntaxShape::Any,
+            "column names to sort dataframe",
+        )
     }
 
     fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {

crates/nu-command/src/commands/dataframe/groupby.rs

@@ -20,7 +20,7 @@ impl WholeStreamCommand for DataFrame {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("dataframe group-by").rest(SyntaxShape::Any, "groupby columns")
+        Signature::build("dataframe group-by").rest("rest", SyntaxShape::Any, "groupby columns")
     }
 
     fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {

crates/nu-command/src/commands/dataframe/join.rs

@@ -177,7 +177,7 @@ fn check_column_datatypes<T: AsRef<str>>(
         ));
     }
 
-    for (l, r) in l_cols.iter().zip(r_cols.iter()) {
+    for (l, r) in l_cols.iter().zip(r_cols) {
         let l_series = df_l
             .column(l.as_ref())
             .map_err(|e| parse_polars_error::<&str>(&e, l_col_span, None))?;

crates/nu-command/src/commands/dataframe/melt.rs

@@ -5,6 +5,7 @@ use nu_protocol::{
     dataframe::{Column, NuDataFrame},
     Signature, SyntaxShape, UntaggedValue, Value,
 };
+use nu_source::Tagged;
 
 use super::utils::convert_columns;
 
@@ -33,6 +34,18 @@ impl WholeStreamCommand for DataFrame {
                 "column names used as value columns",
                 Some('v'),
             )
+            .named(
+                "variable_name",
+                SyntaxShape::String,
+                "optional name for variable column",
+                Some('r'),
+            )
+            .named(
+                "value_name",
+                SyntaxShape::String,
+                "optional name for value column",
+                Some('l'),
+            )
     }
 
     fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
@@ -105,6 +118,9 @@ fn command(mut args: CommandArgs) -> Result<OutputStream, ShellError> {
     let id_col: Vec<Value> = args.req_named("columns")?;
     let val_col: Vec<Value> = args.req_named("values")?;
 
+    let value_name: Option<Tagged<String>> = args.get_flag("value_name")?;
+    let variable_name: Option<Tagged<String>> = args.get_flag("variable_name")?;
+
     let (id_col_string, id_col_span) = convert_columns(&id_col, &tag)?;
     let (val_col_string, val_col_span) = convert_columns(&val_col, &tag)?;
 
@@ -113,11 +129,21 @@ fn command(mut args: CommandArgs) -> Result<OutputStream, ShellError> {
     check_column_datatypes(df.as_ref(), &id_col_string, &id_col_span)?;
     check_column_datatypes(df.as_ref(), &val_col_string, &val_col_span)?;
 
-    let res = df
+    let mut res = df
         .as_ref()
         .melt(&id_col_string, &val_col_string)
         .map_err(|e| parse_polars_error::<&str>(&e, &tag.span, None))?;
 
+    if let Some(name) = &variable_name {
+        res.rename("variable", &name.item)
+            .map_err(|e| parse_polars_error::<&str>(&e, &name.tag.span, None))?;
+    }
+
+    if let Some(name) = &value_name {
+        res.rename("value", &name.item)
+            .map_err(|e| parse_polars_error::<&str>(&e, &name.tag.span, None))?;
+    }
+
     Ok(OutputStream::one(NuDataFrame::dataframe_to_value(res, tag)))
 }
 

crates/nu-command/src/commands/dataframe/mod.rs

@@ -2,6 +2,7 @@ pub mod aggregate;
 pub mod append;
 pub mod column;
 pub mod command;
+pub mod describe;
 pub mod drop;
 pub mod drop_duplicates;
 pub mod drop_nulls;
@@ -17,6 +18,7 @@ pub mod list;
 pub mod melt;
 pub mod open;
 pub mod pivot;
+pub mod rename;
 pub mod sample;
 pub mod select;
 pub mod shape;
@@ -35,6 +37,7 @@ pub use aggregate::DataFrame as DataFrameAggregate;
 pub use append::DataFrame as DataFrameAppend;
 pub use column::DataFrame as DataFrameColumn;
 pub use command::Command as DataFrame;
+pub use describe::DataFrame as DataFrameDescribe;
 pub use drop::DataFrame as DataFrameDrop;
 pub use drop_duplicates::DataFrame as DataFrameDropDuplicates;
 pub use drop_nulls::DataFrame as DataFrameDropNulls;
@@ -50,6 +53,7 @@ pub use list::DataFrame as DataFrameList;
 pub use melt::DataFrame as DataFrameMelt;
 pub use open::DataFrame as DataFrameOpen;
 pub use pivot::DataFrame as DataFramePivot;
+pub use rename::DataFrame as DataFrameRename;
 pub use sample::DataFrame as DataFrameSample;
 pub use select::DataFrame as DataFrameSelect;
 pub use shape::DataFrame as DataFrameShape;
@@ -73,6 +77,17 @@ pub use series::DataFrameArgTrue;
 pub use series::DataFrameArgUnique;
 pub use series::DataFrameConcatenate;
 pub use series::DataFrameContains;
+pub use series::DataFrameCumulative;
+pub use series::DataFrameGetDay;
+pub use series::DataFrameGetHour;
+pub use series::DataFrameGetMinute;
+pub use series::DataFrameGetMonth;
+pub use series::DataFrameGetNanoSecond;
+pub use series::DataFrameGetOrdinal;
+pub use series::DataFrameGetSecond;
+pub use series::DataFrameGetWeek;
+pub use series::DataFrameGetWeekDay;
+pub use series::DataFrameGetYear;
 pub use series::DataFrameIsDuplicated;
 pub use series::DataFrameIsIn;
 pub use series::DataFrameIsNotNull;
@@ -83,10 +98,12 @@ pub use series::DataFrameNUnique;
 pub use series::DataFrameNot;
 pub use series::DataFrameReplace;
 pub use series::DataFrameReplaceAll;
+pub use series::DataFrameRolling;
 pub use series::DataFrameSeriesRename;
 pub use series::DataFrameSet;
 pub use series::DataFrameSetWithIdx;
 pub use series::DataFrameShift;
+pub use series::DataFrameStrFTime;
 pub use series::DataFrameStringLengths;
 pub use series::DataFrameStringSlice;
 pub use series::DataFrameToLowercase;

crates/nu-command/src/commands/dataframe/pivot.rs

@@ -100,7 +100,7 @@ fn command(mut args: CommandArgs) -> Result<OutputStream, ShellError> {
 
     let mut groupby = nu_groupby.to_groupby()?;
 
-    let pivot = groupby.pivot(pivot_col.item.as_ref(), value_col.item.as_ref());
+    let pivot = groupby.pivot(&pivot_col.item, &value_col.item);
 
     let res = match op {
         Operation::Mean => pivot.mean(),
@@ -120,7 +120,7 @@ fn check_pivot_column(
     col: &Tagged<String>,
 ) -> Result<(), ShellError> {
     let series = df
-        .column(col.item.as_ref())
+        .column(&col.item)
         .map_err(|e| parse_polars_error::<&str>(&e, &col.tag.span, None))?;
 
     match series.dtype() {
@@ -146,7 +146,7 @@ fn check_value_column(
     col: &Tagged<String>,
 ) -> Result<(), ShellError> {
     let series = df
-        .column(col.item.as_ref())
+        .column(&col.item)
         .map_err(|e| parse_polars_error::<&str>(&e, &col.tag.span, None))?;
 
     match series.dtype() {

crates/nu-command/src/commands/dataframe/rename.rs

@@ -0,0 +1,81 @@
+use crate::prelude::*;
+use nu_engine::WholeStreamCommand;
+use nu_errors::ShellError;
+use nu_protocol::{
+    dataframe::{Column, NuDataFrame},
+    Signature, SyntaxShape, UntaggedValue,
+};
+
+use nu_source::Tagged;
+
+use super::utils::parse_polars_error;
+pub struct DataFrame;
+
+impl WholeStreamCommand for DataFrame {
+    fn name(&self) -> &str {
+        "dataframe rename-col"
+    }
+
+    fn usage(&self) -> &str {
+        "[DataFrame] rename a dataframe column"
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("dataframe rename-col")
+            .required("from", SyntaxShape::String, "column name to be renamed")
+            .required("to", SyntaxShape::String, "new column name")
+    }
+
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
+        command(args)
+    }
+
+    fn examples(&self) -> Vec<Example> {
+        vec![Example {
+            description: "Renames a dataframe column",
+            example: "[[a b]; [1 2] [3 4]] | dataframe to-df | dataframe rename-col a ab",
+            result: Some(vec![NuDataFrame::try_from_columns(
+                vec![
+                    Column::new(
+                        "ab".to_string(),
+                        vec![UntaggedValue::int(1).into(), UntaggedValue::int(3).into()],
+                    ),
+                    Column::new(
+                        "b".to_string(),
+                        vec![UntaggedValue::int(2).into(), UntaggedValue::int(4).into()],
+                    ),
+                ],
+                &Span::default(),
+            )
+            .expect("simple df for test should not fail")
+            .into_value(Tag::default())]),
+        }]
+    }
+}
+
+fn command(mut args: CommandArgs) -> Result<OutputStream, ShellError> {
+    let tag = args.call_info.name_tag.clone();
+    let from: Tagged<String> = args.req(0)?;
+    let to: Tagged<String> = args.req(1)?;
+
+    let (mut df, df_tag) = NuDataFrame::try_from_stream(&mut args.input, &tag.span)?;
+
+    df.as_mut()
+        .rename(&from.item, &to.item)
+        .map_err(|e| parse_polars_error::<&str>(&e, &df_tag.span, None))?;
+
+    Ok(OutputStream::one(df.into_value(tag)))
+}
+
+#[cfg(test)]
+mod tests {
+    use super::DataFrame;
+    use super::ShellError;
+
+    #[test]
+    fn examples_work_as_expected() -> Result<(), ShellError> {
+        use crate::examples::test_dataframe as test_examples;
+
+        test_examples(DataFrame {})
+    }
+}

crates/nu-command/src/commands/dataframe/sample.rs

@@ -41,7 +41,7 @@ impl WholeStreamCommand for DataFrame {
         vec![
             Example {
                 description: "Sample rows from dataframe",
-                example: "[[a b]; [1 2] [3 4]] | dataframe to-df | dataframe sample -r 1",
+                example: "[[a b]; [1 2] [3 4]] | dataframe to-df | dataframe sample -n 1",
                 result: None, // No expected value because sampling is random
             },
             Example {

crates/nu-command/src/commands/dataframe/select.rs

@@ -20,7 +20,7 @@ impl WholeStreamCommand for DataFrame {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("dataframe select").rest(SyntaxShape::Any, "selected column names")
+        Signature::build("dataframe select").rest("rest", SyntaxShape::Any, "selected column names")
     }
 
     fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {

crates/nu-command/src/commands/dataframe/series/contains.rs

@@ -16,7 +16,7 @@ impl WholeStreamCommand for DataFrame {
     }
 
     fn usage(&self) -> &str {
-        "[Series] Checks if a patter is contained in a string"
+        "[Series] Checks if a pattern is contained in a string"
     }
 
     fn signature(&self) -> Signature {
@@ -33,7 +33,7 @@ impl WholeStreamCommand for DataFrame {
 
     fn examples(&self) -> Vec<Example> {
         vec![Example {
-            description: "Returns boolean indicating if patter was found",
+            description: "Returns boolean indicating if pattern was found",
             example: "[abc acb acb] | dataframe to-df | dataframe contains ab",
             result: Some(vec![NuDataFrame::try_from_columns(
                 vec![Column::new(
@@ -68,7 +68,7 @@ fn command(mut args: CommandArgs) -> Result<OutputStream, ShellError> {
     })?;
 
     let res = chunked
-        .contains(pattern.as_str())
+        .contains(&pattern.item)
         .map_err(|e| parse_polars_error::<&str>(&e, &tag.span, None))?;
 
     let df = NuDataFrame::try_from_series(vec![res.into_series()], &tag.span)?;

crates/nu-command/src/commands/dataframe/series/cumulative.rs

@@ -0,0 +1,127 @@
+use crate::prelude::*;
+use nu_engine::WholeStreamCommand;
+use nu_errors::ShellError;
+use nu_protocol::{
+    dataframe::{Column, NuDataFrame},
+    Signature, SyntaxShape, UntaggedValue,
+};
+use nu_source::Tagged;
+use polars::prelude::DataType;
+
+enum CumType {
+    Min,
+    Max,
+    Sum,
+}
+
+impl CumType {
+    fn from_str(roll_type: &str, span: &Span) -> Result<Self, ShellError> {
+        match roll_type {
+            "min" => Ok(Self::Min),
+            "max" => Ok(Self::Max),
+            "sum" => Ok(Self::Sum),
+            _ => Err(ShellError::labeled_error_with_secondary(
+                "Wrong operation",
+                "Operation not valid for cumulative",
+                span,
+                "Perhaps you want to use: max, min, sum",
+                span,
+            )),
+        }
+    }
+
+    fn to_str(&self) -> &'static str {
+        match self {
+            CumType::Min => "cum_min",
+            CumType::Max => "cum_max",
+            CumType::Sum => "cum_sum",
+        }
+    }
+}
+
+pub struct DataFrame;
+
+impl WholeStreamCommand for DataFrame {
+    fn name(&self) -> &str {
+        "dataframe cum"
+    }
+
+    fn usage(&self) -> &str {
+        "[Series] Cumulative calculation for a series"
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("dataframe cum")
+            .required("type", SyntaxShape::String, "rolling operation")
+            .switch("reverse", "Reverse cumulative calculation", Some('r'))
+    }
+
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
+        command(args)
+    }
+
+    fn examples(&self) -> Vec<Example> {
+        vec![Example {
+            description: "Cumulative sum for a series",
+            example: "[1 2 3 4 5] | dataframe to-df | dataframe cum sum",
+            result: Some(vec![NuDataFrame::try_from_columns(
+                vec![Column::new(
+                    "0_cum_sum".to_string(),
+                    vec![
+                        UntaggedValue::int(1).into(),
+                        UntaggedValue::int(3).into(),
+                        UntaggedValue::int(6).into(),
+                        UntaggedValue::int(10).into(),
+                        UntaggedValue::int(15).into(),
+                    ],
+                )],
+                &Span::default(),
+            )
+            .expect("simple df for test should not fail")
+            .into_value(Tag::default())]),
+        }]
+    }
+}
+
+fn command(mut args: CommandArgs) -> Result<OutputStream, ShellError> {
+    let tag = args.call_info.name_tag.clone();
+    let cum_type: Tagged<String> = args.req(0)?;
+    let reverse = args.has_flag("reverse");
+
+    let (df, df_tag) = NuDataFrame::try_from_stream(&mut args.input, &tag.span)?;
+    let series = df.as_series(&df_tag.span)?;
+
+    if let DataType::Object(_) = series.dtype() {
+        return Err(ShellError::labeled_error(
+            "Found object series",
+            "Series of type object cannot be used for cumulative operation",
+            &df_tag.span,
+        ));
+    }
+
+    let cum_type = CumType::from_str(&cum_type.item, &cum_type.tag.span)?;
+    let mut res = match cum_type {
+        CumType::Max => series.cum_max(reverse),
+        CumType::Min => series.cum_min(reverse),
+        CumType::Sum => series.cum_sum(reverse),
+    };
+
+    let name = format!("{}_{}", series.name(), cum_type.to_str());
+    res.rename(&name);
+
+    let df = NuDataFrame::try_from_series(vec![res], &tag.span)?;
+    Ok(OutputStream::one(df.into_value(df_tag)))
+}
+
+#[cfg(test)]
+mod tests {
+    use super::DataFrame;
+    use super::ShellError;
+
+    #[test]
+    fn examples_work_as_expected() -> Result<(), ShellError> {
+        use crate::examples::test_dataframe as test_examples;
+
+        test_examples(DataFrame {})
+    }
+}

crates/nu-command/src/commands/dataframe/series/get_day.rs

@@ -0,0 +1,75 @@
+use crate::{commands::dataframe::utils::parse_polars_error, prelude::*};
+use nu_engine::WholeStreamCommand;
+use nu_errors::ShellError;
+use nu_protocol::{
+    dataframe::{Column, NuDataFrame},
+    Signature, UntaggedValue,
+};
+
+use polars::prelude::IntoSeries;
+
+pub struct DataFrame;
+
+impl WholeStreamCommand for DataFrame {
+    fn name(&self) -> &str {
+        "dataframe get-day"
+    }
+
+    fn usage(&self) -> &str {
+        "[Series] Gets day from date"
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("dataframe get-day")
+    }
+
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
+        command(args)
+    }
+
+    fn examples(&self) -> Vec<Example> {
+        vec![Example {
+            description: "Returns day from a date",
+            example: r#"let dt = ('2020-08-04T16:39:18+00:00' | str to-datetime -z 'UTC');
+    let df = ([$dt $dt] | dataframe to-df);
+    $df | dataframe get-day"#,
+            result: Some(vec![NuDataFrame::try_from_columns(
+                vec![Column::new(
+                    "0".to_string(),
+                    vec![UntaggedValue::int(4).into(), UntaggedValue::int(4).into()],
+                )],
+                &Span::default(),
+            )
+            .expect("simple df for test should not fail")
+            .into_value(Tag::default())]),
+        }]
+    }
+}
+
+fn command(mut args: CommandArgs) -> Result<OutputStream, ShellError> {
+    let tag = args.call_info.name_tag.clone();
+
+    let (df, df_tag) = NuDataFrame::try_from_stream(&mut args.input, &tag.span)?;
+    let series = df.as_series(&df_tag.span)?;
+
+    let casted = series
+        .date64()
+        .map_err(|e| parse_polars_error::<&str>(&e, &df_tag.span, None))?;
+
+    let res = casted.day().into_series();
+    let df = NuDataFrame::try_from_series(vec![res], &tag.span)?;
+    Ok(OutputStream::one(df.into_value(df_tag)))
+}
+
+#[cfg(test)]
+mod tests {
+    use super::DataFrame;
+    use super::ShellError;
+
+    #[test]
+    fn examples_work_as_expected() -> Result<(), ShellError> {
+        use crate::examples::test_dataframe as test_examples;
+
+        test_examples(DataFrame {})
+    }
+}

crates/nu-command/src/commands/dataframe/series/get_hour.rs

@@ -0,0 +1,75 @@
+use crate::{commands::dataframe::utils::parse_polars_error, prelude::*};
+use nu_engine::WholeStreamCommand;
+use nu_errors::ShellError;
+use nu_protocol::{
+    dataframe::{Column, NuDataFrame},
+    Signature, UntaggedValue,
+};
+
+use polars::prelude::IntoSeries;
+
+pub struct DataFrame;
+
+impl WholeStreamCommand for DataFrame {
+    fn name(&self) -> &str {
+        "dataframe get-hour"
+    }
+
+    fn usage(&self) -> &str {
+        "[Series] Gets hour from date"
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("dataframe get-hour")
+    }
+
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
+        command(args)
+    }
+
+    fn examples(&self) -> Vec<Example> {
+        vec![Example {
+            description: "Returns hour from a date",
+            example: r#"let dt = ('2020-08-04T16:39:18+00:00' | str to-datetime -z 'UTC');
+    let df = ([$dt $dt] | dataframe to-df);
+    $df | dataframe get-hour"#,
+            result: Some(vec![NuDataFrame::try_from_columns(
+                vec![Column::new(
+                    "0".to_string(),
+                    vec![UntaggedValue::int(16).into(), UntaggedValue::int(16).into()],
+                )],
+                &Span::default(),
+            )
+            .expect("simple df for test should not fail")
+            .into_value(Tag::default())]),
+        }]
+    }
+}
+
+fn command(mut args: CommandArgs) -> Result<OutputStream, ShellError> {
+    let tag = args.call_info.name_tag.clone();
+
+    let (df, df_tag) = NuDataFrame::try_from_stream(&mut args.input, &tag.span)?;
+    let series = df.as_series(&df_tag.span)?;
+
+    let casted = series
+        .date64()
+        .map_err(|e| parse_polars_error::<&str>(&e, &df_tag.span, None))?;
+
+    let res = casted.hour().into_series();
+    let df = NuDataFrame::try_from_series(vec![res], &tag.span)?;
+    Ok(OutputStream::one(df.into_value(df_tag)))
+}
+
+#[cfg(test)]
+mod tests {
+    use super::DataFrame;
+    use super::ShellError;
+
+    #[test]
+    fn examples_work_as_expected() -> Result<(), ShellError> {
+        use crate::examples::test_dataframe as test_examples;
+
+        test_examples(DataFrame {})
+    }
+}

crates/nu-command/src/commands/dataframe/series/get_minute.rs

@@ -0,0 +1,75 @@
+use crate::{commands::dataframe::utils::parse_polars_error, prelude::*};
+use nu_engine::WholeStreamCommand;
+use nu_errors::ShellError;
+use nu_protocol::{
+    dataframe::{Column, NuDataFrame},
+    Signature, UntaggedValue,
+};
+
+use polars::prelude::IntoSeries;
+
+pub struct DataFrame;
+
+impl WholeStreamCommand for DataFrame {
+    fn name(&self) -> &str {
+        "dataframe get-minute"
+    }
+
+    fn usage(&self) -> &str {
+        "[Series] Gets minute from date"
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("dataframe get-minute")
+    }
+
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
+        command(args)
+    }
+
+    fn examples(&self) -> Vec<Example> {
+        vec![Example {
+            description: "Returns minute from a date",
+            example: r#"let dt = ('2020-08-04T16:39:18+00:00' | str to-datetime -z 'UTC');
+    let df = ([$dt $dt] | dataframe to-df);
+    $df | dataframe get-minute"#,
+            result: Some(vec![NuDataFrame::try_from_columns(
+                vec![Column::new(
+                    "0".to_string(),
+                    vec![UntaggedValue::int(39).into(), UntaggedValue::int(39).into()],
+                )],
+                &Span::default(),
+            )
+            .expect("simple df for test should not fail")
+            .into_value(Tag::default())]),
+        }]
+    }
+}
+
+fn command(mut args: CommandArgs) -> Result<OutputStream, ShellError> {
+    let tag = args.call_info.name_tag.clone();
+
+    let (df, df_tag) = NuDataFrame::try_from_stream(&mut args.input, &tag.span)?;
+    let series = df.as_series(&df_tag.span)?;
+
+    let casted = series
+        .date64()
+        .map_err(|e| parse_polars_error::<&str>(&e, &df_tag.span, None))?;
+
+    let res = casted.minute().into_series();
+    let df = NuDataFrame::try_from_series(vec![res], &tag.span)?;
+    Ok(OutputStream::one(df.into_value(df_tag)))
+}
+
+#[cfg(test)]
+mod tests {
+    use super::DataFrame;
+    use super::ShellError;
+
+    #[test]
+    fn examples_work_as_expected() -> Result<(), ShellError> {
+        use crate::examples::test_dataframe as test_examples;
+
+        test_examples(DataFrame {})
+    }
+}

crates/nu-command/src/commands/dataframe/series/get_month.rs

@@ -0,0 +1,75 @@
+use crate::{commands::dataframe::utils::parse_polars_error, prelude::*};
+use nu_engine::WholeStreamCommand;
+use nu_errors::ShellError;
+use nu_protocol::{
+    dataframe::{Column, NuDataFrame},
+    Signature, UntaggedValue,
+};
+
+use polars::prelude::IntoSeries;
+
+pub struct DataFrame;
+
+impl WholeStreamCommand for DataFrame {
+    fn name(&self) -> &str {
+        "dataframe get-month"
+    }
+
+    fn usage(&self) -> &str {
+        "[Series] Gets month from date"
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("dataframe get-month")
+    }
+
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
+        command(args)
+    }
+
+    fn examples(&self) -> Vec<Example> {
+        vec![Example {
+            description: "Returns month from a date",
+            example: r#"let dt = ('2020-08-04T16:39:18+00:00' | str to-datetime -z 'UTC');
+    let df = ([$dt $dt] | dataframe to-df);
+    $df | dataframe get-month"#,
+            result: Some(vec![NuDataFrame::try_from_columns(
+                vec![Column::new(
+                    "0".to_string(),
+                    vec![UntaggedValue::int(8).into(), UntaggedValue::int(8).into()],
+                )],
+                &Span::default(),
+            )
+            .expect("simple df for test should not fail")
+            .into_value(Tag::default())]),
+        }]
+    }
+}
+
+fn command(mut args: CommandArgs) -> Result<OutputStream, ShellError> {
+    let tag = args.call_info.name_tag.clone();
+
+    let (df, df_tag) = NuDataFrame::try_from_stream(&mut args.input, &tag.span)?;
+    let series = df.as_series(&df_tag.span)?;
+
+    let casted = series
+        .date64()
+        .map_err(|e| parse_polars_error::<&str>(&e, &df_tag.span, None))?;
+
+    let res = casted.month().into_series();
+    let df = NuDataFrame::try_from_series(vec![res], &tag.span)?;
+    Ok(OutputStream::one(df.into_value(df_tag)))
+}
+
+#[cfg(test)]
+mod tests {
+    use super::DataFrame;
+    use super::ShellError;
+
+    #[test]
+    fn examples_work_as_expected() -> Result<(), ShellError> {
+        use crate::examples::test_dataframe as test_examples;
+
+        test_examples(DataFrame {})
+    }
+}

crates/nu-command/src/commands/dataframe/series/get_nanosecond.rs

@@ -0,0 +1,75 @@
+use crate::{commands::dataframe::utils::parse_polars_error, prelude::*};
+use nu_engine::WholeStreamCommand;
+use nu_errors::ShellError;
+use nu_protocol::{
+    dataframe::{Column, NuDataFrame},
+    Signature, UntaggedValue,
+};
+
+use polars::prelude::IntoSeries;
+
+pub struct DataFrame;
+
+impl WholeStreamCommand for DataFrame {
+    fn name(&self) -> &str {
+        "dataframe get-nanosecond"
+    }
+
+    fn usage(&self) -> &str {
+        "[Series] Gets nanosecond from date"
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("dataframe get-nanosecond")
+    }
+
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
+        command(args)
+    }
+
+    fn examples(&self) -> Vec<Example> {
+        vec![Example {
+            description: "Returns nanosecond from a date",
+            example: r#"let dt = ('2020-08-04T16:39:18+00:00' | str to-datetime -z 'UTC');
+    let df = ([$dt $dt] | dataframe to-df);
+    $df | dataframe get-nanosecond"#,
+            result: Some(vec![NuDataFrame::try_from_columns(
+                vec![Column::new(
+                    "0".to_string(),
+                    vec![UntaggedValue::int(0).into(), UntaggedValue::int(0).into()],
+                )],
+                &Span::default(),
+            )
+            .expect("simple df for test should not fail")
+            .into_value(Tag::default())]),
+        }]
+    }
+}
+
+fn command(mut args: CommandArgs) -> Result<OutputStream, ShellError> {
+    let tag = args.call_info.name_tag.clone();
+
+    let (df, df_tag) = NuDataFrame::try_from_stream(&mut args.input, &tag.span)?;
+    let series = df.as_series(&df_tag.span)?;
+
+    let casted = series
+        .date64()
+        .map_err(|e| parse_polars_error::<&str>(&e, &df_tag.span, None))?;
+
+    let res = casted.nanosecond().into_series();
+    let df = NuDataFrame::try_from_series(vec![res], &tag.span)?;
+    Ok(OutputStream::one(df.into_value(df_tag)))
+}
+
+#[cfg(test)]
+mod tests {
+    use super::DataFrame;
+    use super::ShellError;
+
+    #[test]
+    fn examples_work_as_expected() -> Result<(), ShellError> {
+        use crate::examples::test_dataframe as test_examples;
+
+        test_examples(DataFrame {})
+    }
+}

crates/nu-command/src/commands/dataframe/series/get_ordinal.rs

@@ -0,0 +1,78 @@
+use crate::{commands::dataframe::utils::parse_polars_error, prelude::*};
+use nu_engine::WholeStreamCommand;
+use nu_errors::ShellError;
+use nu_protocol::{
+    dataframe::{Column, NuDataFrame},
+    Signature, UntaggedValue,
+};
+
+use polars::prelude::IntoSeries;
+
+pub struct DataFrame;
+
+impl WholeStreamCommand for DataFrame {
+    fn name(&self) -> &str {
+        "dataframe get-ordinal"
+    }
+
+    fn usage(&self) -> &str {
+        "[Series] Gets ordinal date from date"
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("dataframe get-ordinal")
+    }
+
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
+        command(args)
+    }
+
+    fn examples(&self) -> Vec<Example> {
+        vec![Example {
+            description: "Returns ordinal from a date",
+            example: r#"let dt = ('2020-08-04T16:39:18+00:00' | str to-datetime -z 'UTC');
+    let df = ([$dt $dt] | dataframe to-df);
+    $df | dataframe get-ordinal"#,
+            result: Some(vec![NuDataFrame::try_from_columns(
+                vec![Column::new(
+                    "0".to_string(),
+                    vec![
+                        UntaggedValue::int(217).into(),
+                        UntaggedValue::int(217).into(),
+                    ],
+                )],
+                &Span::default(),
+            )
+            .expect("simple df for test should not fail")
+            .into_value(Tag::default())]),
+        }]
+    }
+}
+
+fn command(mut args: CommandArgs) -> Result<OutputStream, ShellError> {
+    let tag = args.call_info.name_tag.clone();
+
+    let (df, df_tag) = NuDataFrame::try_from_stream(&mut args.input, &tag.span)?;
+    let series = df.as_series(&df_tag.span)?;
+
+    let casted = series
+        .date64()
+        .map_err(|e| parse_polars_error::<&str>(&e, &df_tag.span, None))?;
+
+    let res = casted.ordinal().into_series();
+    let df = NuDataFrame::try_from_series(vec![res], &tag.span)?;
+    Ok(OutputStream::one(df.into_value(df_tag)))
+}
+
+#[cfg(test)]
+mod tests {
+    use super::DataFrame;
+    use super::ShellError;
+
+    #[test]
+    fn examples_work_as_expected() -> Result<(), ShellError> {
+        use crate::examples::test_dataframe as test_examples;
+
+        test_examples(DataFrame {})
+    }
+}

crates/nu-command/src/commands/dataframe/series/get_second.rs

@@ -0,0 +1,75 @@
+use crate::{commands::dataframe::utils::parse_polars_error, prelude::*};
+use nu_engine::WholeStreamCommand;
+use nu_errors::ShellError;
+use nu_protocol::{
+    dataframe::{Column, NuDataFrame},
+    Signature, UntaggedValue,
+};
+
+use polars::prelude::IntoSeries;
+
+pub struct DataFrame;
+
+impl WholeStreamCommand for DataFrame {
+    fn name(&self) -> &str {
+        "dataframe get-second"
+    }
+
+    fn usage(&self) -> &str {
+        "[Series] Gets second from date"
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("dataframe get-second")
+    }
+
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
+        command(args)
+    }
+
+    fn examples(&self) -> Vec<Example> {
+        vec![Example {
+            description: "Returns second from a date",
+            example: r#"let dt = ('2020-08-04T16:39:18+00:00' | str to-datetime -z 'UTC');
+    let df = ([$dt $dt] | dataframe to-df);
+    $df | dataframe get-second"#,
+            result: Some(vec![NuDataFrame::try_from_columns(
+                vec![Column::new(
+                    "0".to_string(),
+                    vec![UntaggedValue::int(18).into(), UntaggedValue::int(18).into()],
+                )],
+                &Span::default(),
+            )
+            .expect("simple df for test should not fail")
+            .into_value(Tag::default())]),
+        }]
+    }
+}
+
+fn command(mut args: CommandArgs) -> Result<OutputStream, ShellError> {
+    let tag = args.call_info.name_tag.clone();
+
+    let (df, df_tag) = NuDataFrame::try_from_stream(&mut args.input, &tag.span)?;
+    let series = df.as_series(&df_tag.span)?;
+
+    let casted = series
+        .date64()
+        .map_err(|e| parse_polars_error::<&str>(&e, &df_tag.span, None))?;
+
+    let res = casted.second().into_series();
+    let df = NuDataFrame::try_from_series(vec![res], &tag.span)?;
+    Ok(OutputStream::one(df.into_value(df_tag)))
+}
+
+#[cfg(test)]
+mod tests {
+    use super::DataFrame;
+    use super::ShellError;
+
+    #[test]
+    fn examples_work_as_expected() -> Result<(), ShellError> {
+        use crate::examples::test_dataframe as test_examples;
+
+        test_examples(DataFrame {})
+    }
+}

crates/nu-command/src/commands/dataframe/series/get_week.rs

@@ -0,0 +1,75 @@
+use crate::{commands::dataframe::utils::parse_polars_error, prelude::*};
+use nu_engine::WholeStreamCommand;
+use nu_errors::ShellError;
+use nu_protocol::{
+    dataframe::{Column, NuDataFrame},
+    Signature, UntaggedValue,
+};
+
+use polars::prelude::IntoSeries;
+
+pub struct DataFrame;
+
+impl WholeStreamCommand for DataFrame {
+    fn name(&self) -> &str {
+        "dataframe get-week"
+    }
+
+    fn usage(&self) -> &str {
+        "[Series] Gets week from date"
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("dataframe get-week")
+    }
+
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
+        command(args)
+    }
+
+    fn examples(&self) -> Vec<Example> {
+        vec![Example {
+            description: "Returns week from a date",
+            example: r#"let dt = ('2020-08-04T16:39:18+00:00' | str to-datetime -z 'UTC');
+    let df = ([$dt $dt] | dataframe to-df);
+    $df | dataframe get-week"#,
+            result: Some(vec![NuDataFrame::try_from_columns(
+                vec![Column::new(
+                    "0".to_string(),
+                    vec![UntaggedValue::int(32).into(), UntaggedValue::int(32).into()],
+                )],
+                &Span::default(),
+            )
+            .expect("simple df for test should not fail")
+            .into_value(Tag::default())]),
+        }]
+    }
+}
+
+fn command(mut args: CommandArgs) -> Result<OutputStream, ShellError> {
+    let tag = args.call_info.name_tag.clone();
+
+    let (df, df_tag) = NuDataFrame::try_from_stream(&mut args.input, &tag.span)?;
+    let series = df.as_series(&df_tag.span)?;
+
+    let casted = series
+        .date64()
+        .map_err(|e| parse_polars_error::<&str>(&e, &df_tag.span, None))?;
+
+    let res = casted.week().into_series();
+    let df = NuDataFrame::try_from_series(vec![res], &tag.span)?;
+    Ok(OutputStream::one(df.into_value(df_tag)))
+}
+
+#[cfg(test)]
+mod tests {
+    use super::DataFrame;
+    use super::ShellError;
+
+    #[test]
+    fn examples_work_as_expected() -> Result<(), ShellError> {
+        use crate::examples::test_dataframe as test_examples;
+
+        test_examples(DataFrame {})
+    }
+}

crates/nu-command/src/commands/dataframe/series/get_weekday.rs

@@ -0,0 +1,75 @@
+use crate::{commands::dataframe::utils::parse_polars_error, prelude::*};
+use nu_engine::WholeStreamCommand;
+use nu_errors::ShellError;
+use nu_protocol::{
+    dataframe::{Column, NuDataFrame},
+    Signature, UntaggedValue,
+};
+
+use polars::prelude::IntoSeries;
+
+pub struct DataFrame;
+
+impl WholeStreamCommand for DataFrame {
+    fn name(&self) -> &str {
+        "dataframe get-weekday"
+    }
+
+    fn usage(&self) -> &str {
+        "[Series] Gets weekday from date"
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("dataframe get-weekday")
+    }
+
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
+        command(args)
+    }
+
+    fn examples(&self) -> Vec<Example> {
+        vec![Example {
+            description: "Returns weekday from a date",
+            example: r#"let dt = ('2020-08-04T16:39:18+00:00' | str to-datetime -z 'UTC');
+    let df = ([$dt $dt] | dataframe to-df);
+    $df | dataframe get-weekday"#,
+            result: Some(vec![NuDataFrame::try_from_columns(
+                vec![Column::new(
+                    "0".to_string(),
+                    vec![UntaggedValue::int(1).into(), UntaggedValue::int(1).into()],
+                )],
+                &Span::default(),
+            )
+            .expect("simple df for test should not fail")
+            .into_value(Tag::default())]),
+        }]
+    }
+}
+
+fn command(mut args: CommandArgs) -> Result<OutputStream, ShellError> {
+    let tag = args.call_info.name_tag.clone();
+
+    let (df, df_tag) = NuDataFrame::try_from_stream(&mut args.input, &tag.span)?;
+    let series = df.as_series(&df_tag.span)?;
+
+    let casted = series
+        .date64()
+        .map_err(|e| parse_polars_error::<&str>(&e, &df_tag.span, None))?;
+
+    let res = casted.weekday().into_series();
+    let df = NuDataFrame::try_from_series(vec![res], &tag.span)?;
+    Ok(OutputStream::one(df.into_value(df_tag)))
+}
+
+#[cfg(test)]
+mod tests {
+    use super::DataFrame;
+    use super::ShellError;
+
+    #[test]
+    fn examples_work_as_expected() -> Result<(), ShellError> {
+        use crate::examples::test_dataframe as test_examples;
+
+        test_examples(DataFrame {})
+    }
+}

crates/nu-command/src/commands/dataframe/series/get_year.rs

@@ -0,0 +1,78 @@
+use crate::{commands::dataframe::utils::parse_polars_error, prelude::*};
+use nu_engine::WholeStreamCommand;
+use nu_errors::ShellError;
+use nu_protocol::{
+    dataframe::{Column, NuDataFrame},
+    Signature, UntaggedValue,
+};
+
+use polars::prelude::IntoSeries;
+
+pub struct DataFrame;
+
+impl WholeStreamCommand for DataFrame {
+    fn name(&self) -> &str {
+        "dataframe get-year"
+    }
+
+    fn usage(&self) -> &str {
+        "[Series] Gets year from date"
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("dataframe get-year")
+    }
+
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
+        command(args)
+    }
+
+    fn examples(&self) -> Vec<Example> {
+        vec![Example {
+            description: "Returns year from a date",
+            example: r#"let dt = ('2020-08-04T16:39:18+00:00' | str to-datetime -z 'UTC');
+    let df = ([$dt $dt] | dataframe to-df);
+    $df | dataframe get-year"#,
+            result: Some(vec![NuDataFrame::try_from_columns(
+                vec![Column::new(
+                    "0".to_string(),
+                    vec![
+                        UntaggedValue::int(2020).into(),
+                        UntaggedValue::int(2020).into(),
+                    ],
+                )],
+                &Span::default(),
+            )
+            .expect("simple df for test should not fail")
+            .into_value(Tag::default())]),
+        }]
+    }
+}
+
+fn command(mut args: CommandArgs) -> Result<OutputStream, ShellError> {
+    let tag = args.call_info.name_tag.clone();
+
+    let (df, df_tag) = NuDataFrame::try_from_stream(&mut args.input, &tag.span)?;
+    let series = df.as_series(&df_tag.span)?;
+
+    let casted = series
+        .date64()
+        .map_err(|e| parse_polars_error::<&str>(&e, &df_tag.span, None))?;
+
+    let res = casted.year().into_series();
+    let df = NuDataFrame::try_from_series(vec![res], &tag.span)?;
+    Ok(OutputStream::one(df.into_value(df_tag)))
+}
+
+#[cfg(test)]
+mod tests {
+    use super::DataFrame;
+    use super::ShellError;
+
+    #[test]
+    fn examples_work_as_expected() -> Result<(), ShellError> {
+        use crate::examples::test_dataframe as test_examples;
+
+        test_examples(DataFrame {})
+    }
+}

crates/nu-command/src/commands/dataframe/series/mod.rs

@@ -7,6 +7,17 @@ pub mod arg_true;
 pub mod arg_unique;
 pub mod concatenate;
 pub mod contains;
+pub mod cumulative;
+pub mod get_day;
+pub mod get_hour;
+pub mod get_minute;
+pub mod get_month;
+pub mod get_nanosecond;
+pub mod get_ordinal;
+pub mod get_second;
+pub mod get_week;
+pub mod get_weekday;
+pub mod get_year;
 pub mod is_duplicated;
 pub mod is_in;
 pub mod is_not_null;
@@ -18,11 +29,13 @@ pub mod not;
 pub mod rename;
 pub mod replace;
 pub mod replace_all;
+pub mod rolling;
 pub mod set;
 pub mod set_with_idx;
 pub mod shift;
 pub mod str_lengths;
 pub mod str_slice;
+pub mod strftime;
 pub mod to_lowercase;
 pub mod to_uppercase;
 pub mod unique;
@@ -37,6 +50,17 @@ pub use arg_true::DataFrame as DataFrameArgTrue;
 pub use arg_unique::DataFrame as DataFrameArgUnique;
 pub use concatenate::DataFrame as DataFrameConcatenate;
 pub use contains::DataFrame as DataFrameContains;
+pub use cumulative::DataFrame as DataFrameCumulative;
+pub use get_day::DataFrame as DataFrameGetDay;
+pub use get_hour::DataFrame as DataFrameGetHour;
+pub use get_minute::DataFrame as DataFrameGetMinute;
+pub use get_month::DataFrame as DataFrameGetMonth;
+pub use get_nanosecond::DataFrame as DataFrameGetNanoSecond;
+pub use get_ordinal::DataFrame as DataFrameGetOrdinal;
+pub use get_second::DataFrame as DataFrameGetSecond;
+pub use get_week::DataFrame as DataFrameGetWeek;
+pub use get_weekday::DataFrame as DataFrameGetWeekDay;
+pub use get_year::DataFrame as DataFrameGetYear;
 pub use is_duplicated::DataFrame as DataFrameIsDuplicated;
 pub use is_in::DataFrame as DataFrameIsIn;
 pub use is_not_null::DataFrame as DataFrameIsNotNull;
@@ -48,11 +72,13 @@ pub use not::DataFrame as DataFrameNot;
 pub use rename::DataFrame as DataFrameSeriesRename;
 pub use replace::DataFrame as DataFrameReplace;
 pub use replace_all::DataFrame as DataFrameReplaceAll;
+pub use rolling::DataFrame as DataFrameRolling;
 pub use set::DataFrame as DataFrameSet;
 pub use set_with_idx::DataFrame as DataFrameSetWithIdx;
 pub use shift::DataFrame as DataFrameShift;
 pub use str_lengths::DataFrame as DataFrameStringLengths;
 pub use str_slice::DataFrame as DataFrameStringSlice;
+pub use strftime::DataFrame as DataFrameStrFTime;
 pub use to_lowercase::DataFrame as DataFrameToLowercase;
 pub use to_uppercase::DataFrame as DataFrameToUppercase;
 pub use unique::DataFrame as DataFrameUnique;

crates/nu-command/src/commands/dataframe/series/rename.rs

@@ -60,7 +60,7 @@ fn command(mut args: CommandArgs) -> Result<OutputStream, ShellError> {
 
     let mut series = df.as_series(&df_tag.span)?;
 
-    series.rename(name.item.as_ref());
+    series.rename(&name.item);
 
     let df = NuDataFrame::try_from_series(vec![series], &tag.span)?;
     Ok(OutputStream::one(df.into_value(df_tag)))

crates/nu-command/src/commands/dataframe/series/replace.rs

@@ -77,7 +77,7 @@ fn command(mut args: CommandArgs) -> Result<OutputStream, ShellError> {
     })?;
 
     let mut res = chunked
-        .replace(pattern.as_str(), replace.as_str())
+        .replace(&pattern.item, &replace.item)
         .map_err(|e| parse_polars_error::<&str>(&e, &tag.span, None))?;
 
     res.rename(series.name());

crates/nu-command/src/commands/dataframe/series/replace_all.rs

@@ -77,7 +77,7 @@ fn command(mut args: CommandArgs) -> Result<OutputStream, ShellError> {
     })?;
 
     let mut res = chunked
-        .replace_all(pattern.as_str(), replace.as_str())
+        .replace_all(&pattern.item, &replace.item)
         .map_err(|e| parse_polars_error::<&str>(&e, &tag.span, None))?;
 
     res.rename(series.name());

crates/nu-command/src/commands/dataframe/series/rolling.rs

@@ -0,0 +1,176 @@
+use crate::{commands::dataframe::utils::parse_polars_error, prelude::*};
+use nu_engine::WholeStreamCommand;
+use nu_errors::ShellError;
+use nu_protocol::{
+    dataframe::{Column, NuDataFrame},
+    Signature, SyntaxShape, UntaggedValue,
+};
+use nu_source::Tagged;
+use polars::prelude::DataType;
+
+enum RollType {
+    Min,
+    Max,
+    Sum,
+    Mean,
+}
+
+impl RollType {
+    fn from_str(roll_type: &str, span: &Span) -> Result<Self, ShellError> {
+        match roll_type {
+            "min" => Ok(Self::Min),
+            "max" => Ok(Self::Max),
+            "sum" => Ok(Self::Sum),
+            "mean" => Ok(Self::Mean),
+            _ => Err(ShellError::labeled_error_with_secondary(
+                "Wrong operation",
+                "Operation not valid for rolling",
+                span,
+                "Perhaps you want to use: max, min, sum, mean",
+                span,
+            )),
+        }
+    }
+
+    fn to_str(&self) -> &'static str {
+        match self {
+            RollType::Min => "rolling_min",
+            RollType::Max => "rolling_max",
+            RollType::Sum => "rolling_sum",
+            RollType::Mean => "rolling_mean",
+        }
+    }
+}
+
+pub struct DataFrame;
+
+impl WholeStreamCommand for DataFrame {
+    fn name(&self) -> &str {
+        "dataframe rolling"
+    }
+
+    fn usage(&self) -> &str {
+        "[Series] Rolling calculation for a series"
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("dataframe rolling")
+            .required("type", SyntaxShape::String, "rolling operation")
+            .required("window", SyntaxShape::Int, "Window size for rolling")
+            .switch("ignore_nulls", "Ignore nulls in column", Some('i'))
+    }
+
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
+        command(args)
+    }
+
+    fn examples(&self) -> Vec<Example> {
+        vec![
+            Example {
+                description: "Rolling sum for a series",
+                example:
+                    "[1 2 3 4 5] | dataframe to-df | dataframe rolling sum 2 | dataframe drop-nulls",
+                result: Some(vec![NuDataFrame::try_from_columns(
+                    vec![Column::new(
+                        "0_rolling_sum".to_string(),
+                        vec![
+                            UntaggedValue::int(3).into(),
+                            UntaggedValue::int(5).into(),
+                            UntaggedValue::int(7).into(),
+                            UntaggedValue::int(9).into(),
+                        ],
+                    )],
+                    &Span::default(),
+                )
+                .expect("simple df for test should not fail")
+                .into_value(Tag::default())]),
+            },
+            Example {
+                description: "Rolling max for a series",
+                example:
+                    "[1 2 3 4 5] | dataframe to-df | dataframe rolling max 2 | dataframe drop-nulls",
+                result: Some(vec![NuDataFrame::try_from_columns(
+                    vec![Column::new(
+                        "0_rolling_max".to_string(),
+                        vec![
+                            UntaggedValue::int(2).into(),
+                            UntaggedValue::int(3).into(),
+                            UntaggedValue::int(4).into(),
+                            UntaggedValue::int(5).into(),
+                        ],
+                    )],
+                    &Span::default(),
+                )
+                .expect("simple df for test should not fail")
+                .into_value(Tag::default())]),
+            },
+        ]
+    }
+}
+
+fn command(mut args: CommandArgs) -> Result<OutputStream, ShellError> {
+    let tag = args.call_info.name_tag.clone();
+    let roll_type: Tagged<String> = args.req(0)?;
+    let window_size: Tagged<i64> = args.req(1)?;
+    let ignore_nulls = args.has_flag("ignore_nulls");
+
+    let (df, df_tag) = NuDataFrame::try_from_stream(&mut args.input, &tag.span)?;
+    let series = df.as_series(&df_tag.span)?;
+
+    if let DataType::Object(_) = series.dtype() {
+        return Err(ShellError::labeled_error(
+            "Found object series",
+            "Series of type object cannot be used for rolling operation",
+            &df_tag.span,
+        ));
+    }
+
+    let roll_type = RollType::from_str(&roll_type.item, &roll_type.tag.span)?;
+    let res = match roll_type {
+        RollType::Max => series.rolling_max(
+            window_size.item as u32,
+            None,
+            ignore_nulls,
+            window_size.item as u32,
+        ),
+        RollType::Min => series.rolling_min(
+            window_size.item as u32,
+            None,
+            ignore_nulls,
+            window_size.item as u32,
+        ),
+        RollType::Sum => series.rolling_sum(
+            window_size.item as u32,
+            None,
+            ignore_nulls,
+            window_size.item as u32,
+        ),
+        RollType::Mean => series.rolling_mean(
+            window_size.item as u32,
+            None,
+            ignore_nulls,
+            window_size.item as u32,
+        ),
+    };
+
+    let mut res = res.map_err(|e| parse_polars_error::<&str>(&e, &df_tag.span, None))?;
+
+    let name = format!("{}_{}", series.name(), roll_type.to_str());
+    res.rename(&name);
+
+    let df = NuDataFrame::try_from_series(vec![res], &tag.span)?;
+    Ok(OutputStream::one(df.into_value(df_tag)))
+}
+
+#[cfg(test)]
+mod tests {
+    use super::DataFrame;
+    use super::ShellError;
+
+    #[test]
+    fn examples_work_as_expected() -> Result<(), ShellError> {
+        use crate::examples::test_dataframe as test_examples;
+
+        test_examples(DataFrame {})
+    }
+}

crates/nu-command/src/commands/dataframe/series/strftime.rs

@@ -0,0 +1,80 @@
+use crate::{commands::dataframe::utils::parse_polars_error, prelude::*};
+use nu_engine::WholeStreamCommand;
+use nu_errors::ShellError;
+use nu_protocol::{
+    dataframe::{Column, NuDataFrame},
+    Signature, SyntaxShape, UntaggedValue,
+};
+
+use nu_source::Tagged;
+use polars::prelude::IntoSeries;
+
+pub struct DataFrame;
+
+impl WholeStreamCommand for DataFrame {
+    fn name(&self) -> &str {
+        "dataframe strftime"
+    }
+
+    fn usage(&self) -> &str {
+        "[Series] Formats date based on string rule"
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("dataframe strftime").required("fmt", SyntaxShape::String, "Format rule")
+    }
+
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
+        command(args)
+    }
+
+    fn examples(&self) -> Vec<Example> {
+        vec![Example {
+            description: "Formats date",
+            example: r#"let dt = ('2020-08-04T16:39:18+00:00' | str to-datetime -z 'UTC');
+    let df = ([$dt $dt] | dataframe to-df);
+    $df | dataframe strftime "%Y/%m/%d""#,
+            result: Some(vec![NuDataFrame::try_from_columns(
+                vec![Column::new(
+                    "0".to_string(),
+                    vec![
+                        UntaggedValue::string("2020/08/04").into(),
+                        UntaggedValue::string("2020/08/04").into(),
+                    ],
+                )],
+                &Span::default(),
+            )
+            .expect("simple df for test should not fail")
+            .into_value(Tag::default())]),
+        }]
+    }
+}
+
+fn command(mut args: CommandArgs) -> Result<OutputStream, ShellError> {
+    let tag = args.call_info.name_tag.clone();
+    let fmt: Tagged<String> = args.req(0)?;
+
+    let (df, df_tag) = NuDataFrame::try_from_stream(&mut args.input, &tag.span)?;
+    let series = df.as_series(&df_tag.span)?;
+
+    let casted = series
+        .date64()
+        .map_err(|e| parse_polars_error::<&str>(&e, &df_tag.span, None))?;
+
+    let res = casted.strftime(&fmt.item).into_series();
+    let df = NuDataFrame::try_from_series(vec![res], &tag.span)?;
+    Ok(OutputStream::one(df.into_value(df_tag)))
+}
+
+#[cfg(test)]
+mod tests {
+    use super::DataFrame;
+    use super::ShellError;
+
+    #[test]
+    fn examples_work_as_expected() -> Result<(), ShellError> {
+        use crate::examples::test_dataframe as test_examples;
+
+        test_examples(DataFrame {})
+    }
+}

crates/nu-command/src/commands/dataframe/sort.rs

@@ -21,7 +21,7 @@ impl WholeStreamCommand for DataFrame {
     fn signature(&self) -> Signature {
         Signature::build("dataframe sort")
             .switch("reverse", "invert sort", Some('r'))
-            .rest(SyntaxShape::Any, "column names to sort dataframe")
+            .rest("rest", SyntaxShape::Any, "column names to sort dataframe")
     }
 
     fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {

crates/nu-command/src/commands/dataframe/take.rs

@@ -111,9 +111,12 @@ fn command(mut args: CommandArgs) -> Result<OutputStream, ShellError> {
         ShellError::labeled_error("Empty stream", "No value found in the stream", &tag)
     })?;
 
-    match value.value {
+    match &value.value {
         UntaggedValue::DataFrame(df) => {
-            let res = df.as_ref().take(indices);
+            let res = df
+                .as_ref()
+                .take(indices)
+                .map_err(|e| parse_polars_error::<&str>(&e, &value.tag.span, None))?;
 
             Ok(OutputStream::one(NuDataFrame::dataframe_to_value(res, tag)))
         }

crates/nu-command/src/commands/dataframe/to_csv.rs

@@ -45,7 +45,7 @@ impl WholeStreamCommand for DataFrame {
         vec![
             Example {
                 description: "Saves dataframe to csv file",
-                example: "[[a b]; [1 2] [3 4]] | dataframe to-df | dataframe to_csv test.csv",
+                example: "[[a b]; [1 2] [3 4]] | dataframe to-df | dataframe to-csv test.csv",
                 result: None,
             },
             Example {
@@ -64,14 +64,10 @@ fn command(mut args: CommandArgs) -> Result<OutputStream, ShellError> {
     let delimiter: Option<Tagged<String>> = args.get_flag("delimiter")?;
     let no_header: bool = args.has_flag("no_header");
 
-    let (mut df, _) = NuDataFrame::try_from_stream(&mut args.input, &tag.span)?;
+    let (df, _) = NuDataFrame::try_from_stream(&mut args.input, &tag.span)?;
 
     let mut file = File::create(&file_name.item).map_err(|e| {
-        ShellError::labeled_error(
-            "Error with file name",
-            format!("{}", e),
-            &file_name.tag.span,
-        )
+        ShellError::labeled_error("Error with file name", e.to_string(), &file_name.tag.span)
     })?;
 
     let writer = CsvWriter::new(&mut file);
@@ -103,7 +99,7 @@ fn command(mut args: CommandArgs) -> Result<OutputStream, ShellError> {
     };
 
     writer
-        .finish(df.as_mut())
+        .finish(df.as_ref())
         .map_err(|e| parse_polars_error::<&str>(&e, &file_name.tag.span, None))?;
 
     let tagged_value = Value {

crates/nu-command/src/commands/dataframe/to_parquet.rs

@@ -48,18 +48,14 @@ fn command(mut args: CommandArgs) -> Result<OutputStream, ShellError> {
     let tag = args.call_info.name_tag.clone();
     let file_name: Tagged<PathBuf> = args.req(0)?;
 
-    let (mut df, _) = NuDataFrame::try_from_stream(&mut args.input, &tag.span)?;
+    let (df, _) = NuDataFrame::try_from_stream(&mut args.input, &tag.span)?;
 
     let file = File::create(&file_name.item).map_err(|e| {
-        ShellError::labeled_error(
-            "Error with file name",
-            format!("{}", e),
-            &file_name.tag.span,
-        )
+        ShellError::labeled_error("Error with file name", e.to_string(), &file_name.tag.span)
     })?;
 
     ParquetWriter::new(file)
-        .finish(df.as_mut())
+        .finish(df.as_ref())
         .map_err(|e| parse_polars_error::<&str>(&e, &file_name.tag.span, None))?;
 
     let tagged_value = Value {

crates/nu-command/src/commands/dataframe/utils.rs

@@ -46,30 +46,32 @@ pub(crate) fn parse_polars_error<T: AsRef<str>>(
     span: &Span,
     secondary: Option<T>,
 ) -> ShellError {
-    let (msg, label) = match e {
-        PolarsError::PolarsArrowError(_) => ("PolarsArrow Error", format!("{}", e)),
-        PolarsError::ArrowError(_) => ("Arrow Error", format!("{}", e)),
-        PolarsError::InvalidOperation(_) => ("Invalid Operation", format!("{}", e)),
-        PolarsError::DataTypeMisMatch(_) => ("Data Type Mismatch", format!("{}", e)),
-        PolarsError::NotFound(_) => ("Not Found", format!("{}", e)),
-        PolarsError::ShapeMisMatch(_) => ("Shape Mismatch", format!("{}", e)),
-        PolarsError::Other(_) => ("Other", format!("{}", e)),
-        PolarsError::OutOfBounds(_) => ("Out Of Bounds", format!("{}", e)),
-        PolarsError::NoSlice => ("No Slice", format!("{}", e)),
-        PolarsError::NoData(_) => ("No Data", format!("{}", e)),
-        PolarsError::ValueError(_) => ("Value Error", format!("{}", e)),
-        PolarsError::MemoryNotAligned => ("Memory Not Aligned", format!("{}", e)),
-        PolarsError::ParquetError(_) => ("Parquet Error", format!("{}", e)),
-        PolarsError::RandError(_) => ("Rand Error", format!("{}", e)),
-        PolarsError::HasNullValues(_) => ("Has Null Values", format!("{}", e)),
-        PolarsError::UnknownSchema(_) => ("Unknown Schema", format!("{}", e)),
-        PolarsError::Various(_) => ("Various", format!("{}", e)),
-        PolarsError::Io(_) => ("Io Error", format!("{}", e)),
-        PolarsError::Regex(_) => ("Regex Error", format!("{}", e)),
-        PolarsError::Duplicate(_) => ("Duplicate Error", format!("{}", e)),
-        PolarsError::ImplementationError => ("Implementation Error", format!("{}", e)),
+    let msg = match e {
+        PolarsError::PolarsArrowError(_) => "PolarsArrow Error",
+        PolarsError::ArrowError(_) => "Arrow Error",
+        PolarsError::InvalidOperation(_) => "Invalid Operation",
+        PolarsError::DataTypeMisMatch(_) => "Data Type Mismatch",
+        PolarsError::NotFound(_) => "Not Found",
+        PolarsError::ShapeMisMatch(_) => "Shape Mismatch",
+        PolarsError::Other(_) => "Other",
+        PolarsError::OutOfBounds(_) => "Out Of Bounds",
+        PolarsError::NoSlice => "No Slice",
+        PolarsError::NoData(_) => "No Data",
+        PolarsError::ValueError(_) => "Value Error",
+        PolarsError::MemoryNotAligned => "Memory Not Aligned",
+        PolarsError::ParquetError(_) => "Parquet Error",
+        PolarsError::RandError(_) => "Rand Error",
+        PolarsError::HasNullValues(_) => "Has Null Values",
+        PolarsError::UnknownSchema(_) => "Unknown Schema",
+        PolarsError::Various(_) => "Various",
+        PolarsError::Io(_) => "Io Error",
+        PolarsError::Regex(_) => "Regex Error",
+        PolarsError::Duplicate(_) => "Duplicate Error",
+        PolarsError::ImplementationError => "Implementation Error",
     };
 
+    let label = e.to_string();
+
     match secondary {
         None => ShellError::labeled_error(msg, label, span),
         Some(s) => ShellError::labeled_error_with_secondary(msg, label, span, s.as_ref(), span),

crates/nu-command/src/commands/dataframe/with_column.rs

@@ -82,7 +82,7 @@ fn command(mut args: CommandArgs) -> Result<OutputStream, ShellError> {
 
     let mut series = df.as_series(&value.tag.span)?;
 
-    let series = series.rename(name.item.as_ref()).clone();
+    let series = series.rename(&name.item).clone();
 
     let (mut df, _) = NuDataFrame::try_from_stream(&mut args.input, &tag.span)?;
 

crates/nu-command/src/commands/env/autoenv_trust.rs

@@ -31,12 +31,12 @@ impl WholeStreamCommand for AutoenvTrust {
                 value: UntaggedValue::Primitive(Primitive::String(ref path)),
                 tag: _,
             }) => {
-                let mut dir = fs::canonicalize(path)?;
+                let mut dir = nu_path::canonicalize(path)?;
                 dir.push(".nu-env");
                 dir
             }
             _ => {
-                let mut dir = fs::canonicalize(std::env::current_dir()?)?;
+                let mut dir = nu_path::canonicalize(std::env::current_dir()?)?;
                 dir.push(".nu-env");
                 dir
             }

crates/nu-command/src/commands/env/autoenv_untrust.rs

@@ -30,7 +30,7 @@ impl WholeStreamCommand for AutoenvUntrust {
                 value: UntaggedValue::Primitive(Primitive::String(ref path)),
                 tag: _,
             }) => {
-                let mut dir = fs::canonicalize(path)?;
+                let mut dir = nu_path::canonicalize(path)?;
                 dir.push(".nu-env");
                 dir
             }
@@ -61,7 +61,7 @@ impl WholeStreamCommand for AutoenvUntrust {
         let mut doc = String::new();
         file.read_to_string(&mut doc)?;
 
-        let mut allowed: Trusted = toml::from_str(doc.as_str()).unwrap_or_else(|_| Trusted::new());
+        let mut allowed: Trusted = toml::from_str(&doc).unwrap_or_else(|_| Trusted::new());
 
         let file_to_untrust = file_to_untrust.to_string_lossy().to_string();
 

crates/nu-command/src/commands/env/let_env.rs

@@ -1,5 +1,7 @@
+use std::convert::TryInto;
+
 use crate::prelude::*;
-use nu_engine::{evaluate_baseline_expr, WholeStreamCommand};
+use nu_engine::{evaluate_baseline_expr, EnvVar, WholeStreamCommand};
 
 use nu_errors::ShellError;
 use nu_protocol::{hir::CapturedBlock, hir::ClassifiedCommand, Signature, SyntaxShape};
@@ -90,9 +92,7 @@ pub fn set_env(args: CommandArgs) -> Result<ActionStream, ShellError> {
 
     ctx.scope.exit_scope();
 
-    let value = value?;
-    let value = value.as_string()?;
-
+    let value: EnvVar = value?.try_into()?;
     let name = name.item;
 
     // Note: this is a special case for setting the context from a command

crates/nu-command/src/commands/env/load_env.rs

@@ -1,5 +1,7 @@
+use std::convert::TryInto;
+
 use crate::prelude::*;
-use nu_engine::WholeStreamCommand;
+use nu_engine::{EnvVar, WholeStreamCommand};
 
 use nu_errors::ShellError;
 use nu_protocol::{Signature, SyntaxShape, Value};
@@ -60,14 +62,17 @@ fn load_env_from_table(
 
         for (key, value) in value.row_entries() {
             if key == "name" {
-                var_name = Some(value.as_string()?);
+                var_name = Some(value);
             } else if key == "value" {
-                var_value = Some(value.as_string()?);
+                var_value = Some(value);
             }
         }
 
         match (var_name, var_value) {
-            (Some(name), Some(value)) => ctx.scope.add_env_var(name, value),
+            (Some(name), Some(value)) => {
+                let env_var: EnvVar = value.try_into()?;
+                ctx.scope.add_env_var(name.as_string()?, env_var);
+            }
             _ => {
                 return Err(ShellError::labeled_error(
                     r#"Expected each row in the table to have a "name" and "value" field."#,

crates/nu-command/src/commands/env/with_env.rs

@@ -1,5 +1,8 @@
+use std::convert::TryInto;
+
 use crate::prelude::*;
 use nu_engine::run_block;
+use nu_engine::EnvVar;
 use nu_engine::WholeStreamCommand;
 use nu_errors::ShellError;
 use nu_protocol::{
@@ -73,20 +76,20 @@ fn with_env(args: CommandArgs) -> Result<ActionStream, ShellError> {
     let variable: Value = args.req(0)?;
     let block: CapturedBlock = args.req(1)?;
 
-    let mut env = IndexMap::new();
+    let mut env: IndexMap<String, EnvVar> = IndexMap::new();
 
     match &variable.value {
         UntaggedValue::Table(table) => {
             if table.len() == 1 {
                 // single row([[X W]; [Y Z]])
                 for (k, v) in table[0].row_entries() {
-                    env.insert(k.clone(), v.convert_to_string());
+                    env.insert(k.clone(), v.try_into()?);
                 }
             } else {
                 // primitive values([X Y W Z])
                 for row in table.chunks(2) {
                     if row.len() == 2 && row[0].is_primitive() && row[1].is_primitive() {
-                        env.insert(row[0].convert_to_string(), row[1].convert_to_string());
+                        env.insert(row[0].convert_to_string(), (&row[1]).try_into()?);
                     }
                 }
             }
@@ -94,7 +97,7 @@ fn with_env(args: CommandArgs) -> Result<ActionStream, ShellError> {
         // when get object by `open x.json` or `from json`
         UntaggedValue::Row(row) => {
             for (k, v) in &row.entries {
-                env.insert(k.clone(), v.convert_to_string());
+                env.insert(k.clone(), v.try_into()?);
             }
         }
         _ => {

crates/nu-command/src/commands/filesystem/mkdir.rs

@@ -12,6 +12,7 @@ impl WholeStreamCommand for Mkdir {
     fn signature(&self) -> Signature {
         Signature::build("mkdir")
             .rest(
+                "rest",
                 SyntaxShape::FilePath,
                 "the name(s) of the path(s) to create",
             )

crates/nu-command/src/commands/filesystem/open.rs

@@ -6,6 +6,7 @@ use log::debug;
 use nu_engine::StringOrBinary;
 use nu_engine::WholeStreamCommand;
 use nu_errors::ShellError;
+use nu_path::canonicalize;
 use nu_protocol::{CommandAction, ReturnSuccess, Signature, SyntaxShape, UntaggedValue, Value};
 use nu_source::{AnchorLocation, Span, Tagged};
 use std::path::{Path, PathBuf};
@@ -172,9 +173,9 @@ fn open(args: CommandArgs) -> Result<ActionStream, ShellError> {
             Ok(StringOrBinary::String(s)) => {
                 ReturnSuccess::value(UntaggedValue::string(s).into_value(file_tag))
             }
-            Ok(StringOrBinary::Binary(b)) => ReturnSuccess::value(
-                UntaggedValue::binary(b.into_iter().collect()).into_value(file_tag),
-            ),
+            Ok(StringOrBinary::Binary(b)) => {
+                ReturnSuccess::value(UntaggedValue::binary(b).into_value(file_tag))
+            }
             Err(se) => Err(se),
         }
     });
@@ -193,7 +194,7 @@ pub fn fetch(
     // TODO: I don't understand the point of this? Maybe for better error reporting
     let mut cwd = PathBuf::from(cwd);
     cwd.push(location);
-    let nice_location = dunce::canonicalize(&cwd).map_err(|e| match e.kind() {
+    let nice_location = canonicalize(&cwd).map_err(|e| match e.kind() {
         std::io::ErrorKind::NotFound => ShellError::labeled_error(
             format!("Cannot find file {:?}", cwd),
             "cannot find file",

crates/nu-command/src/commands/filesystem/rm.rs

@@ -26,7 +26,11 @@ impl WholeStreamCommand for Remove {
             )
             .switch("recursive", "delete subdirectories recursively", Some('r'))
             .switch("force", "suppress error when no file", Some('f'))
-            .rest(SyntaxShape::GlobPattern, "the file path(s) to remove")
+            .rest(
+                "rest",
+                SyntaxShape::GlobPattern,
+                "the file path(s) to remove",
+            )
     }
 
     fn usage(&self) -> &str {

crates/nu-command/src/commands/filesystem/save.rs

@@ -142,6 +142,7 @@ impl WholeStreamCommand for Save {
                 "treat values as-is rather than auto-converting based on file extension",
                 Some('r'),
             )
+            .switch("append", "append values rather than overriding", Some('a'))
     }
 
     fn usage(&self) -> &str {
@@ -165,6 +166,7 @@ fn save(args: CommandArgs) -> Result<OutputStream, ShellError> {
 
     let path: Option<Tagged<PathBuf>> = args.opt(0)?;
     let save_raw = args.has_flag("raw");
+    let append = args.has_flag("append");
 
     let input: Vec<Value> = args.input.collect();
     if path.is_none() {
@@ -231,7 +233,7 @@ fn save(args: CommandArgs) -> Result<OutputStream, ShellError> {
         };
     };
 
-    shell_manager.save(&full_path, &content?, name.span)
+    shell_manager.save(&full_path, &content?, name.span, append)
 }
 
 fn string_from(input: &[Value]) -> String {
@@ -239,7 +241,7 @@ fn string_from(input: &[Value]) -> String {
 
     if !input.is_empty() {
         let mut first = true;
-        for i in input.iter() {
+        for i in input {
             if !first {
                 save_data.push('\n');
             } else {

crates/nu-command/src/commands/filesystem/touch.rs

@@ -19,7 +19,7 @@ impl WholeStreamCommand for Touch {
                 SyntaxShape::FilePath,
                 "the path of the file you want to create",
             )
-            .rest(SyntaxShape::FilePath, "additional files to create")
+            .rest("rest", SyntaxShape::FilePath, "additional files to create")
     }
     fn usage(&self) -> &str {
         "Creates one or more files."
@@ -48,7 +48,7 @@ fn touch(args: CommandArgs) -> Result<ActionStream, ShellError> {
     let target: Tagged<PathBuf> = args.req(0)?;
     let rest: Vec<Tagged<PathBuf>> = args.rest(1)?;
 
-    for item in vec![target].into_iter().chain(rest.into_iter()) {
+    for item in vec![target].into_iter().chain(rest) {
         match OpenOptions::new().write(true).create(true).open(&item) {
             Ok(_) => continue,
             Err(err) => {

crates/nu-command/src/commands/filters/append.rs

@@ -45,7 +45,7 @@ impl WholeStreamCommand for Command {
 
         Ok(prepend
             .into_iter()
-            .chain(args.input.into_iter().chain(vec![value]))
+            .chain(args.input.into_iter().chain([value]))
             .into_output_stream())
     }
 

crates/nu-command/src/commands/filters/compact.rs

@@ -17,7 +17,11 @@ impl WholeStreamCommand for Compact {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("compact").rest(SyntaxShape::Any, "the columns to compact from the table")
+        Signature::build("compact").rest(
+            "rest",
+            SyntaxShape::Any,
+            "the columns to compact from the table",
+        )
     }
 
     fn usage(&self) -> &str {

crates/nu-command/src/commands/filters/drop/mod.rs

@@ -1,5 +1,7 @@
 mod column;
 mod command;
+mod nth;
 
 pub use column::SubCommand as DropColumn;
 pub use command::Command as Drop;
+pub use nth::SubCommand as DropNth;

crates/nu-command/src/commands/filters/drop/nth.rs

@@ -0,0 +1,91 @@
+use crate::prelude::*;
+use nu_engine::WholeStreamCommand;
+use nu_errors::ShellError;
+use nu_protocol::{Signature, SyntaxShape, Value};
+use nu_source::Tagged;
+
+pub struct SubCommand;
+
+impl WholeStreamCommand for SubCommand {
+    fn name(&self) -> &str {
+        "drop nth"
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("drop nth")
+            .required(
+                "row number",
+                SyntaxShape::Int,
+                "the number of the row to drop",
+            )
+            .rest("rest", SyntaxShape::Any, "Optionally drop more rows")
+    }
+
+    fn usage(&self) -> &str {
+        "Drops the selected rows."
+    }
+
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
+        drop(args)
+    }
+
+    fn examples(&self) -> Vec<Example> {
+        vec![
+            Example {
+                description: "Drop the second row",
+                example: "echo [first second third] | drop nth 1",
+                result: Some(vec![Value::from("first"), Value::from("third")]),
+            },
+            Example {
+                description: "Drop the first and third rows",
+                example: "echo [first second third] | drop nth 0 2",
+                result: Some(vec![Value::from("second")]),
+            },
+        ]
+    }
+}
+
+fn drop(args: CommandArgs) -> Result<OutputStream, ShellError> {
+    let row_number: Tagged<u64> = args.req(0)?;
+    let and_rows: Vec<Tagged<u64>> = args.rest(1)?;
+    let input = args.input;
+
+    let mut rows: Vec<_> = and_rows.into_iter().map(|x| x.item as usize).collect();
+    rows.push(row_number.item as usize);
+    rows.sort_unstable();
+
+    Ok(DropNthIterator {
+        input,
+        rows,
+        current: 0,
+    }
+    .into_output_stream())
+}
+
+struct DropNthIterator {
+    input: InputStream,
+    rows: Vec<usize>,
+    current: usize,
+}
+
+impl Iterator for DropNthIterator {
+    type Item = Value;
+
+    fn next(&mut self) -> Option<Self::Item> {
+        loop {
+            if let Some(row) = self.rows.get(0) {
+                if self.current == *row {
+                    self.rows.remove(0);
+                    self.current += 1;
+                    let _ = self.input.next();
+                    continue;
+                } else {
+                    self.current += 1;
+                    return self.input.next();
+                }
+            } else {
+                return self.input.next();
+            }
+        }
+    }
+}

crates/nu-command/src/commands/filters/each/command.rs

@@ -69,7 +69,7 @@ impl WholeStreamCommand for Each {
 }
 
 pub fn process_row(
-    captured_block: Arc<Box<CapturedBlock>>,
+    captured_block: Arc<CapturedBlock>,
     context: Arc<EvaluationContext>,
     input: Value,
     external_redirection: ExternalRedirection,
@@ -96,7 +96,7 @@ pub fn process_row(
 
     let result = run_block(
         &captured_block.block,
-        &*context,
+        &context,
         input_stream,
         external_redirection,
     );
@@ -121,13 +121,13 @@ fn each(args: CommandArgs) -> Result<OutputStream, ShellError> {
     let block: CapturedBlock = args.req(0)?;
     let numbered: bool = args.has_flag("numbered");
 
-    let block = Arc::new(Box::new(block));
+    let block = Arc::new(block);
 
     if numbered {
         Ok(args
             .input
             .enumerate()
-            .map(move |input| {
+            .flat_map(move |input| {
                 let block = block.clone();
                 let context = context.clone();
                 let row = make_indexed_item(input.0, input.1);
@@ -137,12 +137,11 @@ fn each(args: CommandArgs) -> Result<OutputStream, ShellError> {
                     Err(e) => OutputStream::one(Value::error(e)),
                 }
             })
-            .flatten()
             .into_output_stream())
     } else {
         Ok(args
             .input
-            .map(move |input| {
+            .flat_map(move |input| {
                 let block = block.clone();
                 let context = context.clone();
 
@@ -151,7 +150,6 @@ fn each(args: CommandArgs) -> Result<OutputStream, ShellError> {
                     Err(e) => OutputStream::one(Value::error(e)),
                 }
             })
-            .flatten()
             .into_output_stream())
     }
 }

crates/nu-command/src/commands/filters/each/group.rs

@@ -43,7 +43,7 @@ impl WholeStreamCommand for EachGroup {
 
         let group_size: Tagged<usize> = args.req(0)?;
         let block: CapturedBlock = args.req(1)?;
-        let block = Arc::new(Box::new(block));
+        let block = Arc::new(block);
 
         let each_group_iterator = EachGroupIterator {
             block,
@@ -58,7 +58,7 @@ impl WholeStreamCommand for EachGroup {
 }
 
 struct EachGroupIterator {
-    block: Arc<Box<CapturedBlock>>,
+    block: Arc<CapturedBlock>,
     context: Arc<EvaluationContext>,
     group_size: usize,
     input: InputStream,
@@ -96,7 +96,7 @@ impl Iterator for EachGroupIterator {
 
 pub(crate) fn run_block_on_vec(
     input: Vec<Value>,
-    block: Arc<Box<CapturedBlock>>,
+    block: Arc<CapturedBlock>,
     context: Arc<EvaluationContext>,
     external_redirection: ExternalRedirection,
 ) -> OutputStream {

crates/nu-command/src/commands/filters/each/window.rs

@@ -49,7 +49,7 @@ impl WholeStreamCommand for EachWindow {
         let block: CapturedBlock = args.req(1)?;
         let stride: Option<Tagged<usize>> = args.get_flag("stride")?;
 
-        let block = Arc::new(Box::new(block));
+        let block = Arc::new(block);
 
         let mut window: Vec<_> = args
             .input
@@ -64,7 +64,7 @@ impl WholeStreamCommand for EachWindow {
         Ok(args
             .input
             .enumerate()
-            .map(move |(i, input)| {
+            .flat_map(move |(i, input)| {
                 // This would probably be more efficient if `last` was a VecDeque
                 // But we can't have that because it needs to be put into a Table
                 window.remove(0);
@@ -86,7 +86,6 @@ impl WholeStreamCommand for EachWindow {
                 }
             })
             .flatten()
-            .flatten()
             .map(Ok)
             .into_input_stream())
     }

crates/nu-command/src/commands/filters/empty.rs

@@ -19,6 +19,7 @@ impl WholeStreamCommand for Command {
     fn signature(&self) -> Signature {
         Signature::build("empty?")
             .rest(
+                "rest",
                 SyntaxShape::ColumnPath,
                 "the names of the columns to check emptiness",
             )
@@ -139,7 +140,7 @@ fn process_row(
 
         let stream = run_block(
             &default_block.block,
-            &*context,
+            context,
             input_stream,
             ExternalRedirection::Stdout,
         );

crates/nu-command/src/commands/filters/flatten.rs

@@ -14,7 +14,11 @@ impl WholeStreamCommand for Command {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("flatten").rest(SyntaxShape::String, "optionally flatten data by column")
+        Signature::build("flatten").rest(
+            "rest",
+            SyntaxShape::String,
+            "optionally flatten data by column",
+        )
     }
 
     fn usage(&self) -> &str {
@@ -52,8 +56,7 @@ fn flatten(args: CommandArgs) -> Result<ActionStream, ShellError> {
     let input = args.input;
 
     Ok(input
-        .map(move |item| flat_value(&columns, &item, &tag).into_iter())
-        .flatten()
+        .flat_map(move |item| flat_value(&columns, &item, &tag))
         .into_action_stream())
 }
 
@@ -92,7 +95,7 @@ fn flat_value(
                         continue;
                     }
 
-                    for (k, v) in mapa.into_iter() {
+                    for (k, v) in mapa {
                         if out.contains_key(k) {
                             out.insert_value(format!("{}_{}", column, k), v.clone());
                         } else {
@@ -155,7 +158,7 @@ fn flat_value(
             let mut expanded = vec![];
 
             if let Some(TableInside::Entries(column, _, entries)) = a_table {
-                for entry in entries.into_iter() {
+                for entry in entries {
                     let mut base = out.clone();
                     base.insert_value(column, entry.clone());
                     expanded.push(base.into_value());
@@ -166,7 +169,7 @@ fn flat_value(
 
             expanded
         } else if item.is_table() {
-            item.table_entries().map(Clone::clone).collect()
+            item.table_entries().cloned().collect()
         } else {
             vec![item.clone()]
         }

crates/nu-command/src/commands/filters/get.rs

@@ -19,6 +19,7 @@ impl WholeStreamCommand for Command {
 
     fn signature(&self) -> Signature {
         Signature::build("get").rest(
+            "rest",
             SyntaxShape::ColumnPath,
             "optionally return additional data by path",
         )
@@ -64,14 +65,12 @@ pub fn get(args: CommandArgs) -> Result<ActionStream, ShellError> {
     } else {
         trace!("get {:?}", column_paths);
         let output_stream = input
-            .map(move |item| {
+            .flat_map(move |item| {
                 column_paths
                     .iter()
-                    .map(move |path| get_output(&item, path))
-                    .flatten()
+                    .flat_map(move |path| get_output(&item, path))
                     .collect::<Vec<_>>()
             })
-            .flatten()
             .into_action_stream();
         Ok(output_stream)
     }