<!--
if this PR closes one or more issues, you can automatically link the PR
with
them by using one of the [*linking
keywords*](https://docs.github.com/en/issues/tracking-your-work-with-issues/linking-a-pull-request-to-an-issue#linking-a-pull-request-to-an-issue-using-a-keyword),
e.g.
- this PR should close #xxxx
- fixes #xxxx
you can also mention related issues, PRs or discussions!
-->
# Description
<!--
Thank you for improving Nushell. Please, check our [contributing
guide](../CONTRIBUTING.md) and talk to the core team before making major
changes.
Description of your pull request goes here. **Provide examples and/or
screenshots** if your changes affect the user experience.
-->
The [nushell/demo](https://github.com/nushell/demo) project successfully
demonstrated running Nushell in the browser using WASM. However, the
current version of Nushell cannot be easily built for the
`wasm32-unknown-unknown` target, the default for `wasm-bindgen`.
This PR introduces initial support for the `wasm32-unknown-unknown`
target by disabling OS-dependent features such as filesystem access, IO,
and platform/system-specific functionality. This separation is achieved
using a new `os` feature in the following crates:
- `nu-cmd-lang`
- `nu-command`
- `nu-engine`
- `nu-protocol`
The `os` feature includes all functionality that interacts with an
operating system. It is enabled by default, but can be disabled using
`--no-default-features`. All crates that depend on these core crates now
use `--no-default-features` to allow compilation for WASM.
To demonstrate compatibility, the following script builds all crates
expected to work with WASM. Direct user interaction, running external
commands, working with plugins, and features requiring `openssl` are out
of scope for now due to their complexity or reliance on C libraries,
which are difficult to compile and link in a WASM environment.
```nushell
[ # compatible crates
"nu-cmd-base",
"nu-cmd-extra",
"nu-cmd-lang",
"nu-color-config",
"nu-command",
"nu-derive-value",
"nu-engine",
"nu-glob",
"nu-json",
"nu-parser",
"nu-path",
"nu-pretty-hex",
"nu-protocol",
"nu-std",
"nu-system",
"nu-table",
"nu-term-grid",
"nu-utils",
"nuon"
] | each {cargo build -p $in --target wasm32-unknown-unknown --no-default-features}
```
## Caveats
This PR has a few caveats:
1. **`miette` and `terminal-size` Dependency Issue**
`miette` depends on `terminal-size`, which uses `rustix` when the target
is not Windows. However, `rustix` requires `std::os::unix`, which is
unavailable in WASM. To address this, I opened a
[PR](https://github.com/eminence/terminal-size/pull/68) for
`terminal-size` to conditionally compile `rustix` only when the target
is Unix. For now, the `Cargo.toml` includes patches to:
- Use my forked version of `terminal-size`.
- ~~Use an unreleased version of `miette` that depends on
`terminal-size@0.4`.~~
These patches are temporary and can be removed once the upstream changes
are merged and released.
2. **Test Output Adjustments**
Due to the slight bump in the `miette` version, one test required
adjustments to accommodate minor formatting changes in the error output,
such as shifted newlines.
# User-Facing Changes
<!-- List of all changes that impact the user experience here. This
helps us keep track of breaking changes. -->
This shouldn't break anything but allows using some crates for targeting
`wasm32-unknown-unknown` to revive the demo page eventually.
# Tests + Formatting
<!--
Don't forget to add tests that cover your changes.
Make sure you've run and fixed any issues with these commands:
- `cargo fmt --all -- --check` to check standard code formatting (`cargo
fmt --all` applies these changes)
- `cargo clippy --workspace -- -D warnings -D clippy::unwrap_used` to
check that you're using the standard code style
- `cargo test --workspace` to check that all tests pass (on Windows make
sure to [enable developer
mode](https://learn.microsoft.com/en-us/windows/apps/get-started/developer-mode-features-and-debugging))
- `cargo run -- -c "use toolkit.nu; toolkit test stdlib"` to run the
tests for the standard library
> **Note**
> from `nushell` you can also use the `toolkit` as follows
> ```bash
> use toolkit.nu # or use an `env_change` hook to activate it
automatically
> toolkit check pr
> ```
-->
- 🟢 `toolkit fmt`
- 🟢 `toolkit clippy`
- 🟢 `toolkit test`
- 🟢 `toolkit test stdlib`
I did not add any extra tests, I just checked that compiling works, also
when using the host target but unselecting the `os` feature.
# After Submitting
<!-- If your PR had any user-facing changes, update [the
documentation](https://github.com/nushell/nushell.github.io) after the
PR is merged, if necessary. This will help us keep the docs up to date.
-->
~~Breaking the wasm support can be easily done by adding some `use`s or
by adding a new dependency, we should definitely add some CI that also
at least builds against wasm to make sure that building for it keep
working.~~
I added a job to build wasm.
---------
Co-authored-by: Ian Manske <ian.manske@pm.me>
# Description
This PR removes the `terminal_size` crate everywhere that it made sense.
I replaced it with crossterm's version called `size`. The places I
didn't remove it were the places that did not have a dependency on
crossterm. So, I thought it was "cheaper" to have a dep on term_size vs
crossterm in those locations.
# Description
By request, this PR introduces a new `--flatten` parameter to the ast
command for generating a more readable version of the AST output. This
enhancement improves usability by allowing users to easily visualize the
structure of the AST.

```nushell
❯ ast 'ls | sort-by type name -i' --flatten --json
[
{
"content": "ls",
"shape": "shape_internalcall",
"span": {
"start": 0,
"end": 2
}
},
{
"content": "|",
"shape": "shape_pipe",
"span": {
"start": 3,
"end": 4
}
},
{
"content": "sort-by",
"shape": "shape_internalcall",
"span": {
"start": 5,
"end": 12
}
},
{
"content": "type",
"shape": "shape_string",
"span": {
"start": 13,
"end": 17
}
},
{
"content": "name",
"shape": "shape_string",
"span": {
"start": 18,
"end": 22
}
},
{
"content": "-i",
"shape": "shape_flag",
"span": {
"start": 23,
"end": 25
}
}
]
❯ ast 'ls | sort-by type name -i' --flatten --json --minify
[{"content":"ls","shape":"shape_internalcall","span":{"start":0,"end":2}},{"content":"|","shape":"shape_pipe","span":{"start":3,"end":4}},{"content":"sort-by","shape":"shape_internalcall","span":{"start":5,"end":12}},{"content":"type","shape":"shape_string","span":{"start":13,"end":17}},{"content":"name","shape":"shape_string","span":{"start":18,"end":22}},{"content":"-i","shape":"shape_flag","span":{"start":23,"end":25}}]
```
# User-Facing Changes
<!-- List of all changes that impact the user experience here. This
helps us keep track of breaking changes. -->
# Tests + Formatting
<!--
Don't forget to add tests that cover your changes.
Make sure you've run and fixed any issues with these commands:
- `cargo fmt --all -- --check` to check standard code formatting (`cargo
fmt --all` applies these changes)
- `cargo clippy --workspace -- -D warnings -D clippy::unwrap_used` to
check that you're using the standard code style
- `cargo test --workspace` to check that all tests pass (on Windows make
sure to [enable developer
mode](https://learn.microsoft.com/en-us/windows/apps/get-started/developer-mode-features-and-debugging))
- `cargo run -- -c "use toolkit.nu; toolkit test stdlib"` to run the
tests for the standard library
> **Note**
> from `nushell` you can also use the `toolkit` as follows
> ```bash
> use toolkit.nu # or use an `env_change` hook to activate it
automatically
> toolkit check pr
> ```
-->
# After Submitting
<!-- If your PR had any user-facing changes, update [the
documentation](https://github.com/nushell/nushell.github.io) after the
PR is merged, if necessary. This will help us keep the docs up to date.
-->
# Description
Removes the `NU_DISABLE_IR` option and some code related to evaluating
blocks with the AST
evaluator.
Does not entirely remove the AST evaluator yet. We still have some
dependencies on expression
evaluation in a few minor places which will take a little bit of effort
to fix.
Also changes `debug profile` to always include instructions, because the
output is a little
confusing otherwise, and removes the different options for
instructions/exprs.
# User-Facing Changes
- `NU_DISABLE_IR` no longer has any effect, and is removed. There is no
way to use the AST
evaluator.
- `debug profile` no longer has `--exprs`, `--instructions` options.
- `debug profile` lists `pc` and `instruction` columns by default now.
# Tests + Formatting
Eval tests fixed to only use IR.
# After Submitting
- [ ] release notes
- [ ] finish removing AST evaluator, come up with solutions for the
expression evaluation.
Nushell currently depends on three different versions of the `windows`
crate: `0.44.0`, `0.52.0`, and `0.54.0`. This PR bumps several
dependencies so that the `nu` binary only depends on `0.56.0`.
On my machine, this PR makes `cargo build` about 10% faster.
The polars plugin still uses its own version of the `windows` crate
though, which is not ideal. We'll need to bump the `polars` crate to fix
that, but it breaks a lot of our code. (`polars 1.0` release anyone?)
Nushell currently depends on three different versions of the `windows`
crate: `0.44.0`, `0.52.0`, and `0.54.0`. This PR bumps several
dependencies so that the `nu` binary only depends on `0.56.0`.
On my machine, this PR makes `cargo build` about 10% faster.
The polars plugin still uses its own version of the `windows` crate
though, which is not ideal. We'll need to bump the `polars` crate to fix
that, but it breaks a lot of our code. (`polars 1.0` release anyone?)
# Description
In this PR I replaced most of the raw usize IDs with
[newtypes](https://doc.rust-lang.org/rust-by-example/generics/new_types.html).
Some other IDs already started using new types and in this PR I did not
want to touch them. To make the implementation less repetitive, I made
use of a generic `Id<T>` with marker structs. If this lands I would try
to move make other IDs also in this pattern.
Also at some places I needed to use `cast`, I'm not sure if the type was
incorrect and therefore casting not needed or if actually different ID
types intermingle sometimes.
# User-Facing Changes
Probably few, if you got a `DeclId` via a function and placed it later
again it will still work.
# Description
Fixes a couple panics:
```
> {} | inspect
Error: x Main thread panicked.
|-> at crates/nu-command/src/debug/inspect_table.rs:87:15
`-> attempt to divide by zero
```
```
> {} | explore
# see an empty column, press Down
Error: x Main thread panicked.
|-> at crates/nu-explore/src/views/cursor/mod.rs:39:9
`-> attempt to subtract with overflow
```
# User-Facing Changes
`{} | inspect` now outputs an empty table:
```
╭─────────────┬────────╮
│ description │ record │
├─────────────┴────────┤
│ │
├──────────────────────┤
```
`{} | explore` opens the help menu.
Both match the empty list behavior.
# Tests
I'm not sure how to test `explore`, as it waits for interaction.
# Description
Add content type metadata to the output of `view source`.
I've gone along with the mime type used [here][xdg], but this shouldn't
be merged until there is consensus #13858.
`to nuon`'s output has content type `application/x-nuon`
[xdg]:
https://gitlab.freedesktop.org/xdg/shared-mime-info/-/merge_requests/231
# User-Facing Changes
Combined with `metadata access`, allows richer display_output hooks.
Might be useful with other commands that make use of content_type like
the `http` commands.
# Description
Add `metadata access`, which allows accessing/inspecting the metadata of
a stream in a closure.
```nu
ls | metadata access {|meta|
...
}
```
- The metadata is provided as an argument to the closure, identical to
the record obtained with `metadata` command.
- `metadata access` passes its input stream into the closure as it is.
- Within the closure, both the metadata and the stream are available.
The closure may modify, collect or pass the stream as it is.
# Motivation
- Without this command, nu code can't act on metadata without losing the
stream, use cases requiring both the stream and metadata must be
implemented either as a built-in or a plugin.
- This command allows users to enhance presentation of data, similar to
`table` coloring the output of `ls`.
# Description
This PR makes it so that non-zero exit codes and termination by signal
are treated as a normal `ShellError`. Currently, these are silent
errors. That is, if an external command fails, then it's code block is
aborted, but the parent block can sometimes continue execution. E.g.,
see #8569 and this example:
```nushell
[1 2] | each { ^false }
```
Before this would give:
```
╭───┬──╮
│ 0 │ │
│ 1 │ │
╰───┴──╯
```
Now, this shows an error:
```
Error: nu:🐚:eval_block_with_input
× Eval block failed with pipeline input
╭─[entry #1:1:2]
1 │ [1 2] | each { ^false }
· ┬
· ╰── source value
╰────
Error: nu:🐚:non_zero_exit_code
× External command had a non-zero exit code
╭─[entry #1:1:17]
1 │ [1 2] | each { ^false }
· ──┬──
· ╰── exited with code 1
╰────
```
This PR fixes#12874, fixes#5960, fixes#10856, and fixes#5347. This
PR also partially addresses #10633 and #10624 (only the last command of
a pipeline is currently checked). It looks like #8569 is already fixed,
but this PR will make sure it is definitely fixed (fixes#8569).
# User-Facing Changes
- Non-zero exit codes and termination by signal now cause an error to be
thrown.
- The error record value passed to a `catch` block may now have an
`exit_code` column containing the integer exit code if the error was due
to an external command.
- Adds new config values, `display_errors.exit_code` and
`display_errors.termination_signal`, which determine whether an error
message should be printed in the respective error cases. For
non-interactive sessions, these are set to `true`, and for interactive
sessions `display_errors.exit_code` is false (via the default config).
# Tests
Added a few tests.
# After Submitting
- Update docs and book.
- Future work:
- Error if other external commands besides the last in a pipeline exit
with a non-zero exit code. Then, deprecate `do -c` since this will be
the default behavior everywhere.
- Add a better mechanism for exit codes and deprecate
`$env.LAST_EXIT_CODE` (it's buggy).
Hi there
Here I am using latest tabled.
My tests shows it does fixes panics, but I am wanna be sure.
@fdncred could you verify that it does fixes those panics/errors?
Closes#13405Closes#12786
# Description
The meaning of the word usage is specific to describing how a command
function is *used* and not a synonym for general description. Usage can
be used to describe the SYNOPSIS or EXAMPLES sections of a man page
where the permitted argument combinations are shown or example *uses*
are given.
Let's not confuse people and call it what it is a description.
Our `help` command already creates its own *Usage* section based on the
available arguments and doesn't refer to the description with usage.
# User-Facing Changes
`help commands` and `scope commands` will now use `description` or
`extra_description`
`usage`-> `description`
`extra_usage` -> `extra_description`
Breaking change in the plugin protocol:
In the signature record communicated with the engine.
`usage`-> `description`
`extra_usage` -> `extra_description`
The same rename also takes place for the methods on
`SimplePluginCommand` and `PluginCommand`
# Tests + Formatting
- Updated plugin protocol specific changes
# After Submitting
- [ ] update plugin protocol doc
# Description
Setting metadata on a byte stream converts it to a list stream. This PR
makes it so that `metadata set` does not alter its input besides the
metadata.
```nushell
open --raw test.json
| metadata set --content-type application/json
| http post https://httpbin.org/post
```
# Description
This adds tracing for each individual instruction to the `Debugger`
trait. Register contents can be inspected both when entering and leaving
an instruction, and if an instruction produced an error, a reference to
the error is also available. It's not the full `EvalContext` but it's
most of the important parts for getting an idea of what's going on.
Added support for all of this to the `Profiler` / `debug profile` as
well, and the output is quite incredible - super verbose, but you can
see every instruction that's executed and also what the result was if
it's an instruction that has a clearly defined output (many do).
# User-Facing Changes
- Added `--instructions` to `debug profile`, which adds the `pc` and
`instruction` columns to the output.
- `--expr` only works in AST mode, and `--instructions` only works in IR
mode. In the wrong mode, the output for those columns is just blank.
# Tests + Formatting
All passing.
# After Submitting
- [ ] release notes
# Description
Allows `Stack` to have a modified local `Config`, which is updated
immediately when `$env.config` is assigned to. This means that even
within a script, commands that come after `$env.config` changes will
always see those changes in `Stack::get_config()`.
Also fixed a lot of cases where `engine_state.get_config()` was used
even when `Stack` was available.
Closes#13324.
# User-Facing Changes
- Config changes apply immediately after the assignment is executed,
rather than whenever config is read by a command that needs it.
- Potentially slower performance when executing a lot of lines that
change `$env.config` one after another. Recommended to get `$env.config`
into a `mut` variable first and do modifications, then assign it back.
- Much faster performance when executing a script that made
modifications to `$env.config`, as the changes are only parsed once.
# Tests + Formatting
All passing.
# After Submitting
- [ ] release notes
# Description
Add a few more options to `view ir` for finding blocks, which I found
myself wanting while trying to trace through the generated code.
If we end up adding support for plugins to call commands that are in
scope by name, this will also make it possible for
`nu_plugin_explore_ir` to just step through IR automatically (by passing
the block/decl ids) without exposing too many internals. With that I
could potentially add keys that allow you to step in to closures or
decls with the press of a button, just by calling `view ir --json`
appropriately.
# User-Facing Changes
- `view ir` can now take names of custom commands that are in scope.
- integer arguments are treated as block IDs, which sometimes show up in
IR (closure, block, row condition literals).
- `--decl-id` provided to treat the argument as a decl ID instead, which
is also sometimes necessary to access something that isn't in scope.
# Description
Fix `view ir` to use `Signature::build()` rather than `new()`, which is
required for `--help` to work. Also add `Category::Debug`, as that's
most appropriate.
# Description
This PR adds an internal representation language to Nushell, offering an
alternative evaluator based on simple instructions, stream-containing
registers, and indexed control flow. The number of registers required is
determined statically at compile-time, and the fixed size required is
allocated upon entering the block.
Each instruction is associated with a span, which makes going backwards
from IR instructions to source code very easy.
Motivations for IR:
1. **Performance.** By simplifying the evaluation path and making it
more cache-friendly and branch predictor-friendly, code that does a lot
of computation in Nushell itself can be sped up a decent bit. Because
the IR is fairly easy to reason about, we can also implement
optimization passes in the future to eliminate and simplify code.
2. **Correctness.** The instructions mostly have very simple and
easily-specified behavior, so hopefully engine changes are a little bit
easier to reason about, and they can be specified in a more formal way
at some point. I have made an effort to document each of the
instructions in the docs for the enum itself in a reasonably specific
way. Some of the errors that would have happened during evaluation
before are now moved to the compilation step instead, because they don't
make sense to check during evaluation.
3. **As an intermediate target.** This is a good step for us to bring
the [`new-nu-parser`](https://github.com/nushell/new-nu-parser) in at
some point, as code generated from new AST can be directly compared to
code generated from old AST. If the IR code is functionally equivalent,
it will behave the exact same way.
4. **Debugging.** With a little bit more work, we can probably give
control over advancing the virtual machine that `IrBlock`s run on to
some sort of external driver, making things like breakpoints and single
stepping possible. Tools like `view ir` and [`explore
ir`](https://github.com/devyn/nu_plugin_explore_ir) make it easier than
before to see what exactly is going on with your Nushell code.
The goal is to eventually replace the AST evaluator entirely, once we're
sure it's working just as well. You can help dogfood this by running
Nushell with `$env.NU_USE_IR` set to some value. The environment
variable is checked when Nushell starts, so config runs with IR, or it
can also be set on a line at the REPL to change it dynamically. It is
also checked when running `do` in case within a script you want to just
run a specific piece of code with or without IR.
# Example
```nushell
view ir { |data|
mut sum = 0
for n in $data {
$sum += $n
}
$sum
}
```
```gas
# 3 registers, 19 instructions, 0 bytes of data
0: load-literal %0, int(0)
1: store-variable var 904, %0 # let
2: drain %0
3: drop %0
4: load-variable %1, var 903
5: iterate %0, %1, end 15 # for, label(1), from(14:)
6: store-variable var 905, %0
7: load-variable %0, var 904
8: load-variable %2, var 905
9: binary-op %0, Math(Plus), %2
10: span %0
11: store-variable var 904, %0
12: load-literal %0, nothing
13: drain %0
14: jump 5
15: drop %0 # label(0), from(5:)
16: drain %0
17: load-variable %0, var 904
18: return %0
```
# Benchmarks
All benchmarks run on a base model Mac Mini M1.
## Iterative Fibonacci sequence
This is about as best case as possible, making use of the much faster
control flow. Most code will not experience a speed improvement nearly
this large.
```nushell
def fib [n: int] {
mut a = 0
mut b = 1
for _ in 2..=$n {
let c = $a + $b
$a = $b
$b = $c
}
$b
}
use std bench
bench { 0..50 | each { |n| fib $n } }
```
IR disabled:
```
╭───────┬─────────────────╮
│ mean │ 1ms 924µs 665ns │
│ min │ 1ms 700µs 83ns │
│ max │ 3ms 450µs 125ns │
│ std │ 395µs 759ns │
│ times │ [list 50 items] │
╰───────┴─────────────────╯
```
IR enabled:
```
╭───────┬─────────────────╮
│ mean │ 452µs 820ns │
│ min │ 427µs 417ns │
│ max │ 540µs 167ns │
│ std │ 17µs 158ns │
│ times │ [list 50 items] │
╰───────┴─────────────────╯
```

##
[gradient_benchmark_no_check.nu](https://github.com/nushell/nu_scripts/blob/main/benchmarks/gradient_benchmark_no_check.nu)
IR disabled:
```
╭───┬──────────────────╮
│ 0 │ 27ms 929µs 958ns │
│ 1 │ 21ms 153µs 459ns │
│ 2 │ 18ms 639µs 666ns │
│ 3 │ 19ms 554µs 583ns │
│ 4 │ 13ms 383µs 375ns │
│ 5 │ 11ms 328µs 208ns │
│ 6 │ 5ms 659µs 542ns │
╰───┴──────────────────╯
```
IR enabled:
```
╭───┬──────────────────╮
│ 0 │ 22ms 662µs │
│ 1 │ 17ms 221µs 792ns │
│ 2 │ 14ms 786µs 708ns │
│ 3 │ 13ms 876µs 834ns │
│ 4 │ 13ms 52µs 875ns │
│ 5 │ 11ms 269µs 666ns │
│ 6 │ 6ms 942µs 500ns │
╰───┴──────────────────╯
```
##
[random-bytes.nu](https://github.com/nushell/nu_scripts/blob/main/benchmarks/random-bytes.nu)
I got pretty random results out of this benchmark so I decided not to
include it. Not clear why.
# User-Facing Changes
- IR compilation errors may appear even if the user isn't evaluating
with IR.
- IR evaluation can be enabled by setting the `NU_USE_IR` environment
variable to any value.
- New command `view ir` pretty-prints the IR for a block, and `view ir
--json` can be piped into an external tool like [`explore
ir`](https://github.com/devyn/nu_plugin_explore_ir).
# Tests + Formatting
All tests are passing with `NU_USE_IR=1`, and I've added some more eval
tests to compare the results for some very core operations. I will
probably want to add some more so we don't have to always check
`NU_USE_IR=1 toolkit test --workspace` on a regular basis.
# After Submitting
- [ ] release notes
- [ ] further documentation of instructions?
- [ ] post-release: publish `nu_plugin_explore_ir`
# Description
This PR introduces a new `Signals` struct to replace our adhoc passing
around of `ctrlc: Option<Arc<AtomicBool>>`. Doing so has a few benefits:
- We can better enforce when/where resetting or triggering an interrupt
is allowed.
- Consolidates `nu_utils::ctrl_c::was_pressed` and other ad-hoc
re-implementations into a single place: `Signals::check`.
- This allows us to add other types of signals later if we want. E.g.,
exiting or suspension.
- Similarly, we can more easily change the underlying implementation if
we need to in the future.
- Places that used to have a `ctrlc` of `None` now use
`Signals::empty()`, so we can double check these usages for correctness
in the future.
This reverts commit 0cfd5fbece.
The original PR messed up syntax higlighting of aliases and causes
panics of completion in the presence of alias.
<!--
if this PR closes one or more issues, you can automatically link the PR
with
them by using one of the [*linking
keywords*](https://docs.github.com/en/issues/tracking-your-work-with-issues/linking-a-pull-request-to-an-issue#linking-a-pull-request-to-an-issue-using-a-keyword),
e.g.
- this PR should close #xxxx
- fixes #xxxx
you can also mention related issues, PRs or discussions!
-->
# Description
<!--
Thank you for improving Nushell. Please, check our [contributing
guide](../CONTRIBUTING.md) and talk to the core team before making major
changes.
Description of your pull request goes here. **Provide examples and/or
screenshots** if your changes affect the user experience.
-->
# User-Facing Changes
<!-- List of all changes that impact the user experience here. This
helps us keep track of breaking changes. -->
# Tests + Formatting
<!--
Don't forget to add tests that cover your changes.
Make sure you've run and fixed any issues with these commands:
- `cargo fmt --all -- --check` to check standard code formatting (`cargo
fmt --all` applies these changes)
- `cargo clippy --workspace -- -D warnings -D clippy::unwrap_used` to
check that you're using the standard code style
- `cargo test --workspace` to check that all tests pass (on Windows make
sure to [enable developer
mode](https://learn.microsoft.com/en-us/windows/apps/get-started/developer-mode-features-and-debugging))
- `cargo run -- -c "use toolkit.nu; toolkit test stdlib"` to run the
tests for the standard library
> **Note**
> from `nushell` you can also use the `toolkit` as follows
> ```bash
> use toolkit.nu # or use an `env_change` hook to activate it
automatically
> toolkit check pr
> ```
-->
# After Submitting
<!-- If your PR had any user-facing changes, update [the
documentation](https://github.com/nushell/nushell.github.io) after the
PR is merged, if necessary. This will help us keep the docs up to date.
-->
<!--
if this PR closes one or more issues, you can automatically link the PR
with
them by using one of the [*linking
keywords*](https://docs.github.com/en/issues/tracking-your-work-with-issues/linking-a-pull-request-to-an-issue#linking-a-pull-request-to-an-issue-using-a-keyword),
e.g.
- this PR should close #xxxx
- fixes #xxxx
you can also mention related issues, PRs or discussions!
-->
# Description
<!--
Thank you for improving Nushell. Please, check our [contributing
guide](../CONTRIBUTING.md) and talk to the core team before making major
changes.
Description of your pull request goes here. **Provide examples and/or
screenshots** if your changes affect the user experience.
-->
Part of https://github.com/nushell/nushell/issues/12963, step 2.
This PR refactors Call and related argument structures to remove their
dependency on `Expression::span` which will be removed in the future.
# User-Facing Changes
<!-- List of all changes that impact the user experience here. This
helps us keep track of breaking changes. -->
Should be none. If you see some error messages that look broken, please
report.
# Tests + Formatting
<!--
Don't forget to add tests that cover your changes.
Make sure you've run and fixed any issues with these commands:
- `cargo fmt --all -- --check` to check standard code formatting (`cargo
fmt --all` applies these changes)
- `cargo clippy --workspace -- -D warnings -D clippy::unwrap_used` to
check that you're using the standard code style
- `cargo test --workspace` to check that all tests pass (on Windows make
sure to [enable developer
mode](https://learn.microsoft.com/en-us/windows/apps/get-started/developer-mode-features-and-debugging))
- `cargo run -- -c "use toolkit.nu; toolkit test stdlib"` to run the
tests for the standard library
> **Note**
> from `nushell` you can also use the `toolkit` as follows
> ```bash
> use toolkit.nu # or use an `env_change` hook to activate it
automatically
> toolkit check pr
> ```
-->
# After Submitting
<!-- If your PR had any user-facing changes, update [the
documentation](https://github.com/nushell/nushell.github.io) after the
PR is merged, if necessary. This will help us keep the docs up to date.
-->
# Description
With #13254, the content-type pipeline metadata field was added. This
pull request allows it to be manipulated with `metadata set`
# User-Facing Changes
* `metadata set` now has a `--content-type` flag
# Description
Provides the ability to use http commands as part of a pipeline.
Additionally, this pull requests extends the pipeline metadata to add a
content_type field. The content_type metadata field allows commands such
as `to json` to set the metadata in the pipeline allowing the http
commands to use it when making requests.
This pull request also introduces the ability to directly stream http
requests from streaming pipelines.
One other small change is that Content-Type will always be set if it is
passed in to the http commands, either indirectly or throw the content
type flag. Previously it was not preserved with requests that were not
of type json or form data.
# User-Facing Changes
* `http post`, `http put`, `http patch`, `http delete` can be used as
part of a pipeline
* `to text`, `to json`, `from json` all set the content_type metadata
field and the http commands will utilize them when making requests.
<!--
if this PR closes one or more issues, you can automatically link the PR
with
them by using one of the [*linking
keywords*](https://docs.github.com/en/issues/tracking-your-work-with-issues/linking-a-pull-request-to-an-issue#linking-a-pull-request-to-an-issue-using-a-keyword),
e.g.
- this PR should close #xxxx
- fixes #xxxx
you can also mention related issues, PRs or discussions!
-->
# Description
<!--
Thank you for improving Nushell. Please, check our [contributing
guide](../CONTRIBUTING.md) and talk to the core team before making major
changes.
Description of your pull request goes here. **Provide examples and/or
screenshots** if your changes affect the user experience.
-->
1. With the `-l` flag, `debug profile` now collects files and line
numbers of profiled pipeline elements

2. Error from the profiled closure will be reported instead of silently
ignored.

# User-Facing Changes
<!-- List of all changes that impact the user experience here. This
helps us keep track of breaking changes. -->
New `--lines(-l)` flag to `debug profile`. The command will also fail if
the profiled closure fails, so technically it is a breaking change.
# Tests + Formatting
<!--
Don't forget to add tests that cover your changes.
Make sure you've run and fixed any issues with these commands:
- `cargo fmt --all -- --check` to check standard code formatting (`cargo
fmt --all` applies these changes)
- `cargo clippy --workspace -- -D warnings -D clippy::unwrap_used` to
check that you're using the standard code style
- `cargo test --workspace` to check that all tests pass (on Windows make
sure to [enable developer
mode](https://learn.microsoft.com/en-us/windows/apps/get-started/developer-mode-features-and-debugging))
- `cargo run -- -c "use toolkit.nu; toolkit test stdlib"` to run the
tests for the standard library
> **Note**
> from `nushell` you can also use the `toolkit` as follows
> ```bash
> use toolkit.nu # or use an `env_change` hook to activate it
automatically
> toolkit check pr
> ```
-->
# After Submitting
<!-- If your PR had any user-facing changes, update [the
documentation](https://github.com/nushell/nushell.github.io) after the
PR is merged, if necessary. This will help us keep the docs up to date.
-->
---------
Co-authored-by: Ian Manske <ian.manske@pm.me>
# Description
Changes `get_full_help` to take a `&dyn Command` instead of multiple
arguments (`&Signature`, `&Examples` `is_parser_keyword`). All of these
arguments can be gathered from a `Command`, so there is no need to pass
the pieces to `get_full_help`.
This PR also fixes an issue where the search terms are not shown if
`--help` is used on a command.
# Description
Kind of a vague title, but this PR does two main things:
1. Rather than overriding functions like `Command::is_parser_keyword`,
this PR instead changes commands to override `Command::command_type`.
The `CommandType` returned by `Command::command_type` is then used to
automatically determine whether `Command::is_parser_keyword` and the
other `is_{type}` functions should return true. These changes allow us
to remove the `CommandType::Other` case and should also guarantee than
only one of the `is_{type}` functions on `Command` will return true.
2. Uses the new, reworked `Command::command_type` function in the `scope
commands` and `which` commands.
# User-Facing Changes
- Breaking change for `scope commands`: multiple columns (`is_builtin`,
`is_keyword`, `is_plugin`, etc.) have been merged into the `type`
column.
- Breaking change: the `which` command can now report `plugin` or
`keyword` instead of `built-in` in the `type` column. It may also now
report `external` instead of `custom` in the `type` column for known
`extern`s.
# Description
This PR introduces a `ByteStream` type which is a `Read`-able stream of
bytes. Internally, it has an enum over three different byte stream
sources:
```rust
pub enum ByteStreamSource {
Read(Box<dyn Read + Send + 'static>),
File(File),
Child(ChildProcess),
}
```
This is in comparison to the current `RawStream` type, which is an
`Iterator<Item = Vec<u8>>` and has to allocate for each read chunk.
Currently, `PipelineData::ExternalStream` serves a weird dual role where
it is either external command output or a wrapper around `RawStream`.
`ByteStream` makes this distinction more clear (via `ByteStreamSource`)
and replaces `PipelineData::ExternalStream` in this PR:
```rust
pub enum PipelineData {
Empty,
Value(Value, Option<PipelineMetadata>),
ListStream(ListStream, Option<PipelineMetadata>),
ByteStream(ByteStream, Option<PipelineMetadata>),
}
```
The PR is relatively large, but a decent amount of it is just repetitive
changes.
This PR fixes#7017, fixes#10763, and fixes#12369.
This PR also improves performance when piping external commands. Nushell
should, in most cases, have competitive pipeline throughput compared to,
e.g., bash.
| Command | Before (MB/s) | After (MB/s) | Bash (MB/s) |
| -------------------------------------------------- | -------------:|
------------:| -----------:|
| `throughput \| rg 'x'` | 3059 | 3744 | 3739 |
| `throughput \| nu --testbin relay o> /dev/null` | 3508 | 8087 | 8136 |
# User-Facing Changes
- This is a breaking change for the plugin communication protocol,
because the `ExternalStreamInfo` was replaced with `ByteStreamInfo`.
Plugins now only have to deal with a single input stream, as opposed to
the previous three streams: stdout, stderr, and exit code.
- The output of `describe` has been changed for external/byte streams.
- Temporary breaking change: `bytes starts-with` no longer works with
byte streams. This is to keep the PR smaller, and `bytes ends-with`
already does not work on byte streams.
- If a process core dumped, then instead of having a `Value::Error` in
the `exit_code` column of the output returned from `complete`, it now is
a `Value::Int` with the negation of the signal number.
# After Submitting
- Update docs and book as necessary
- Release notes (e.g., plugin protocol changes)
- Adapt/convert commands to work with byte streams (high priority is
`str length`, `bytes starts-with`, and maybe `bytes ends-with`).
- Refactor the `tee` code, Devyn has already done some work on this.
---------
Co-authored-by: Devyn Cairns <devyn.cairns@gmail.com>
# Description
Does some misc changes to `ListStream`:
- Moves it into its own module/file separate from `RawStream`.
- `ListStream`s now have an associated `Span`.
- This required changes to `ListStreamInfo` in `nu-plugin`. Note sure if
this is a breaking change for the plugin protocol.
- Hides the internals of `ListStream` but also adds a few more methods.
- This includes two functions to more easily alter a stream (these take
a `ListStream` and return a `ListStream` instead of having to go through
the whole `into_pipeline_data(..)` route).
- `map`: takes a `FnMut(Value) -> Value`
- `modify`: takes a function to modify the inner stream.
# Description
Removes lazy records from the language, following from the reasons
outlined in #12622. Namely, this should make semantics more clear and
will eliminate concerns regarding maintainability.
# User-Facing Changes
- Breaking change: `lazy make` is removed.
- Breaking change: `describe --collect-lazyrecords` flag is removed.
- `sys` and `debug info` now return regular records.
# After Submitting
- Update nushell book if necessary.
- Explore new `sys` and `debug info` APIs to prevent them from taking
too long (e.g., subcommands or taking an optional column/cell-path
argument).
# Description
Continuing from #12568, this PR further reduces the size of `Expr` from
64 to 40 bytes. It also reduces `Expression` from 128 to 96 bytes and
`Type` from 32 to 24 bytes.
This was accomplished by:
- for `Expr` with multiple fields (e.g., `Expr::Thing(A, B, C)`),
merging the fields into new AST struct types and then boxing this struct
(e.g. `Expr::Thing(Box<ABC>)`).
- replacing `Vec<T>` with `Box<[T]>` in multiple places. `Expr`s and
`Expression`s should rarely be mutated, if at all, so this optimization
makes sense.
By reducing the size of these types, I didn't notice a large performance
improvement (at least compared to #12568). But this PR does reduce the
memory usage of nushell. My config is somewhat light so I only noticed a
difference of 1.4MiB (38.9MiB vs 37.5MiB).
---------
Co-authored-by: Stefan Holderbach <sholderbach@users.noreply.github.com>
# Description
Adds two new types in `nu-engine` for evaluating closures: `ClosureEval`
and `ClosureEvalOnce`. This removed some duplicate code and centralizes
our logic for setting up, running, and cleaning up closures. For
example, in the future if we are able to reduce the cloning necessary to
run a closure, then we only have to change the code related to these
types.
`ClosureEval` and `ClosureEvalOnce` are designed with a builder API.
`ClosureEval` is used to run a closure multiple times whereas
`ClosureEvalOnce` is used for a one-shot closure.
# User-Facing Changes
Should be none, unless I messed up one of the command migrations.
Actually, this will fix any unreported environment bugs for commands
that didn't reset the env after running a closure.
# Description
`Value` describes the types of first-class values that users and scripts
can create, manipulate, pass around, and store. However, `Block`s are
not first-class values in the language, so this PR removes it from
`Value`. This removes some unnecessary code, and this change should be
invisible to the user except for the change to `scope modules` described
below.
# User-Facing Changes
Breaking change: the output of `scope modules` was changed so that
`env_block` is now `has_env_block` which is a boolean value instead of a
`Block`.
# After Submitting
Update the language guide possibly.
# Description
This PR adds the ability to set metadata. This is especially useful for
activating LS_COLORS when using table literals.

You can also set the filepath metadata, although I'm not really user how
useful this is. We may end up removing this option entirely.
```nushell
❯ "crates" | metadata set --datasource-filepath $'(pwd)/crates' | metadata
╭────────┬───────────────────────────────────╮
│ source │ /Users/fdncred/src/nushell/crates │
╰────────┴───────────────────────────────────╯
```
No file paths are checked. You could also do this.
```nushell
❯ "crates" | metadata set --datasource-filepath $'a/b/c/d/crates' | metadata
╭────────┬────────────────╮
│ source │ a/b/c/d/crates │
╰────────┴────────────────╯
```
The command name and parameter names are still WIP. We could change
them.
There are currently 3 kinds of metadata in nushell.
```rust
pub enum DataSource {
Ls,
HtmlThemes,
FilePath(PathBuf),
}
```
I've skipped adding `HtmlThemes` because it seems to be specific to our
`to html` command only.
# Description
Duration can not be negative, and an underflow causes a panic.
This should fix#12539 as from what I can tell that bug was caused in
`nu-explore:📟:events` from subtracting durations, but I figured
this might be more widespread, and saturating to zero generally makes
sense.
I also added the relevant clippy lint to try to prevent this from
happening in the future. I can't think of a reason we would ever want to
subtract durations without checking first.
cc @fdncred
# Tests + Formatting
- 🟢 `toolkit fmt`
- 🟢 `toolkit clippy`
- 🟢 `toolkit test`
- 🟢 `toolkit test stdlib`
# Description
This adds a `SharedCow` type as a transparent copy-on-write pointer that
clones to unique on mutate.
As an initial test, the `Record` within `Value::Record` is shared.
There are some pretty big wins for performance. I'll post benchmark
results in a comment. The biggest winner is nested access, as that would
have cloned the records for each cell path follow before and it doesn't
have to anymore.
The reusability of the `SharedCow` type is nice and I think it could be
used to clean up the previous work I did with `Arc` in `EngineState`.
It's meant to be a mostly transparent clone-on-write that just clones on
`.to_mut()` or `.into_owned()` if there are actually multiple
references, but avoids cloning if the reference is unique.
# User-Facing Changes
- `Value::Record` field is a different type (plugin authors)
# Tests + Formatting
- 🟢 `toolkit fmt`
- 🟢 `toolkit clippy`
- 🟢 `toolkit test`
- 🟢 `toolkit test stdlib`
# After Submitting
- [ ] use for `EngineState`
- [ ] use for `Value::List`
# Description
Fixes: #11996
After this change `let t = timeit ^ls` will list current directory to
stdout.
```
❯ let t = timeit ^ls
CODE_OF_CONDUCT.md Cargo.lock Cross.toml README.md aaa benches devdocs here11 scripts target toolkit.nu wix
CONTRIBUTING.md Cargo.toml LICENSE a.txt assets crates docker rust-toolchain.toml src tests typos.toml
```
If user don't want such behavior, he can redirect the stdout to `std
null-stream` easily
```
> use std
> let t = timeit { ^ls o> (std null-device) }
```
# User-Facing Changes
NaN
# Tests + Formatting
Done
# After Submitting
Nan
---------
Co-authored-by: Ian Manske <ian.manske@pm.me>
# Description
Currently, `Range` is a struct with a `from`, `to`, and `incr` field,
which are all type `Value`. This PR changes `Range` to be an enum over
`IntRange` and `FloatRange` for better type safety / stronger compile
time guarantees.
Fixes: #11778Fixes: #11777Fixes: #11776Fixes: #11775Fixes: #11774Fixes: #11773Fixes: #11769.
# User-Facing Changes
Hopefully none, besides bug fixes.
Although, the `serde` representation might have changed.
<!--
if this PR closes one or more issues, you can automatically link the PR
with
them by using one of the [*linking
keywords*](https://docs.github.com/en/issues/tracking-your-work-with-issues/linking-a-pull-request-to-an-issue#linking-a-pull-request-to-an-issue-using-a-keyword),
e.g.
- this PR should close #xxxx
- fixes #xxxx
you can also mention related issues, PRs or discussions!
-->
# Description
<!--
Thank you for improving Nushell. Please, check our [contributing
guide](../CONTRIBUTING.md) and talk to the core team before making major
changes.
Description of your pull request goes here. **Provide examples and/or
screenshots** if your changes affect the user experience.
-->
Resolves#11800.
```
~/CodingProjects/nushell> def "url expand" [$urls:any = []]: [string -> string, list -> table] {
::: let urls = ($in | default $urls)
::: def expand-link [] {
::: http head --redirect-mode manual $in | where name == location | get value.0
::: }
::: match ($urls | describe) {
::: string => { $urls | expand-link }
::: $type if ($type =~ list) => { $urls | wrap link | insert expanded {|url| $url.link | expand-link}}
::: }
::: }; view source "url expand"
def "url expand" [ $urls: any = [] ]: [string -> string, list<any> -> table] {
let urls = ($in | default $urls)
def expand-link [] {
http head --redirect-mode manual $in | where name == location | get value.0
}
match ($urls | describe) {
string => { $urls | expand-link }
$type if ($type =~ list) => { $urls | wrap link | insert expanded {|url| $url.link | expand-link}}
}
}
```
# User-Facing Changes
<!-- List of all changes that impact the user experience here. This
helps us keep track of breaking changes. -->
`view source` now
- adds quotes to commands with spaces
- shows default argument values
- shows type signatures
# Tests + Formatting
<!--
Don't forget to add tests that cover your changes.
Make sure you've run and fixed any issues with these commands:
- `cargo fmt --all -- --check` to check standard code formatting (`cargo
fmt --all` applies these changes)
- `cargo clippy --workspace -- -D warnings -D clippy::unwrap_used` to
check that you're using the standard code style
- `cargo test --workspace` to check that all tests pass (on Windows make
sure to [enable developer
mode](https://learn.microsoft.com/en-us/windows/apps/get-started/developer-mode-features-and-debugging))
- `cargo run -- -c "use std testing; testing run-tests --path
crates/nu-std"` to run the tests for the standard library
> **Note**
> from `nushell` you can also use the `toolkit` as follows
> ```bash
> use toolkit.nu # or use an `env_change` hook to activate it
automatically
> toolkit check pr
> ```
-->
# After Submitting
<!-- If your PR had any user-facing changes, update [the
documentation](https://github.com/nushell/nushell.github.io) after the
PR is merged, if necessary. This will help us keep the docs up to date.
-->
# Description
Where possible, this PR replaces usages of raw `libc` bindings to
instead use safe interfaces from the `nix` crate. Where not possible,
the `libc` version reexported through `nix` was used instead of having a
separate `libc` dependency.
# Description
The second `Value` is redundant and will consume five extra bytes on
each transmission of a custom value to/from a plugin.
# User-Facing Changes
This is a breaking change to the plugin protocol.
The [example in the protocol
reference](https://www.nushell.sh/contributor-book/plugin_protocol_reference.html#value)
becomes
```json
{
"Custom": {
"val": {
"type": "PluginCustomValue",
"name": "database",
"data": [36, 190, 127, 40, 12, 3, 46, 83],
"notify_on_drop": true
},
"span": {
"start": 320,
"end": 340
}
}
}
```
instead of
```json
{
"CustomValue": {
...
}
}
```
# After Submitting
Update plugin protocol reference
# Description
When implementing a `Command`, one must also import all the types
present in the function signatures for `Command`. This makes it so that
we often import the same set of types in each command implementation
file. E.g., something like this:
```rust
use nu_protocol::ast::Call;
use nu_protocol::engine::{Command, EngineState, Stack};
use nu_protocol::{
record, Category, Example, IntoInterruptiblePipelineData, IntoPipelineData, PipelineData,
ShellError, Signature, Span, Type, Value,
};
```
This PR adds the `nu_engine::command_prelude` module which contains the
necessary and commonly used types to implement a `Command`:
```rust
// command_prelude.rs
pub use crate::CallExt;
pub use nu_protocol::{
ast::{Call, CellPath},
engine::{Command, EngineState, Stack},
record, Category, Example, IntoInterruptiblePipelineData, IntoPipelineData, IntoSpanned,
PipelineData, Record, ShellError, Signature, Span, Spanned, SyntaxShape, Type, Value,
};
```
This should reduce the boilerplate needed to implement a command and
also gives us a place to track the breadth of the `Command` API. I tried
to be conservative with what went into the prelude modules, since it
might be hard/annoying to remove items from the prelude in the future.
Let me know if something should be included or excluded.
# Description
Get rid of two parallel `Vec`s in `StateDelta` and `EngineState`, that
also duplicated span information. Use a struct with documenting fields.
Also use `Arc<str>` and `Arc<[u8]>` for the allocations as they are
never modified and cloned often (see #12229 for the first improvement).
This also makes the representation more compact as no capacity is
necessary.
# User-Facing Changes
API breakage on `EngineState`/`StateWorkingSet`/`StateDelta` that should
not really affect plugin authors.
# Description
This makes many of the larger objects in `EngineState` into `Arc`, and
uses `Arc::make_mut` to do clone-on-write if the reference is not
unique. This is generally very cheap, giving us the best of both worlds
- allowing us to mutate without cloning if we have an exclusive
reference, and cloning if we don't.
This started as more of a curiosity for me after remembering that
`Arc::make_mut` exists and can make using `Arc` for mostly immutable
data that sometimes needs to be changed very convenient, and also after
hearing someone complain about memory usage on Discord - this is a
somewhat significant win for that.
The exact objects that were wrapped in `Arc`:
- `files`, `file_contents` - the strings and byte buffers
- `decls` - the whole `Vec`, but mostly to avoid lots of individual
`malloc()` calls on Clone rather than for memory usage
- `blocks` - the blocks themselves, rather than the outer Vec
- `modules` - the modules themselves, rather than the outer Vec
- `env_vars`, `previous_env_vars` - the entire maps
- `config`
The changes required were relatively minimal, but this is a breaking API
change. In particular, blocks are added as Arcs, to allow the parser
cache functionality to work.
With my normal nu config, running on Linux, this saves me about 15 MiB
of process memory usage when running interactively (65 MiB → 50 MiB).
This also makes quick command executions cheaper, particularly since
every REPL loop now involves a clone of the engine state so that we can
recover from a panic. It also reduces memory usage where engine state
needs to be cloned and sent to another thread or kept within an
iterator.
# User-Facing Changes
Shouldn't be any, since it's all internal stuff, but it does change some
public interfaces so it's a breaking change
[Context on
Discord](https://discord.com/channels/601130461678272522/855947301380947968/1219425984990806207)
# Description
- Rename `CustomValue::value_string()` to `type_name()` to reflect its
usage better.
- Change print behavior to always call `to_base_value()` first, to give
the custom value better control over the output.
- Change `describe --detailed` to show the type name as the subtype,
rather than trying to describe the base value.
- Change custom `Type` to use `type_name()` rather than `typetag_name()`
to make things like `PluginCustomValue` more transparent
One question: should `describe --detailed` still include a description
of the base value somewhere? I'm torn on it, it seems possibly useful
for some things (maybe sqlite databases?), but having `describe -d` not
include the custom type name anywhere felt weird. Another option would
be to add another method to `CustomValue` for info to be displayed in
`describe`, so that it can be more type-specific?
# User-Facing Changes
Everything above has implications for printing and `describe` on custom
values
# Tests + Formatting
- 🟢 `toolkit fmt`
- 🟢 `toolkit clippy`
- 🟢 `toolkit test`
- 🟢 `toolkit test stdlib`
# Description
The PR overhauls how IO redirection is handled, allowing more explicit
and fine-grain control over `stdout` and `stderr` output as well as more
efficient IO and piping.
To summarize the changes in this PR:
- Added a new `IoStream` type to indicate the intended destination for a
pipeline element's `stdout` and `stderr`.
- The `stdout` and `stderr` `IoStream`s are stored in the `Stack` and to
avoid adding 6 additional arguments to every eval function and
`Command::run`. The `stdout` and `stderr` streams can be temporarily
overwritten through functions on `Stack` and these functions will return
a guard that restores the original `stdout` and `stderr` when dropped.
- In the AST, redirections are now directly part of a `PipelineElement`
as a `Option<Redirection>` field instead of having multiple different
`PipelineElement` enum variants for each kind of redirection. This
required changes to the parser, mainly in `lite_parser.rs`.
- `Command`s can also set a `IoStream` override/redirection which will
apply to the previous command in the pipeline. This is used, for
example, in `ignore` to allow the previous external command to have its
stdout redirected to `Stdio::null()` at spawn time. In contrast, the
current implementation has to create an os pipe and manually consume the
output on nushell's side. File and pipe redirections (`o>`, `e>`, `e>|`,
etc.) have precedence over overrides from commands.
This PR improves piping and IO speed, partially addressing #10763. Using
the `throughput` command from that issue, this PR gives the following
speedup on my setup for the commands below:
| Command | Before (MB/s) | After (MB/s) | Bash (MB/s) |
| --------------------------- | -------------:| ------------:|
-----------:|
| `throughput o> /dev/null` | 1169 | 52938 | 54305 |
| `throughput \| ignore` | 840 | 55438 | N/A |
| `throughput \| null` | Error | 53617 | N/A |
| `throughput \| rg 'x'` | 1165 | 3049 | 3736 |
| `(throughput) \| rg 'x'` | 810 | 3085 | 3815 |
(Numbers above are the median samples for throughput)
This PR also paves the way to refactor our `ExternalStream` handling in
the various commands. For example, this PR already fixes the following
code:
```nushell
^sh -c 'echo -n "hello "; sleep 0; echo "world"' | find "hello world"
```
This returns an empty list on 0.90.1 and returns a highlighted "hello
world" on this PR.
Since the `stdout` and `stderr` `IoStream`s are available to commands
when they are run, then this unlocks the potential for more convenient
behavior. E.g., the `find` command can disable its ansi highlighting if
it detects that the output `IoStream` is not the terminal. Knowing the
output streams will also allow background job output to be redirected
more easily and efficiently.
# User-Facing Changes
- External commands returned from closures will be collected (in most
cases):
```nushell
1..2 | each {|_| nu -c "print a" }
```
This gives `["a", "a"]` on this PR, whereas this used to print "a\na\n"
and then return an empty list.
```nushell
1..2 | each {|_| nu -c "print -e a" }
```
This gives `["", ""]` and prints "a\na\n" to stderr, whereas this used
to return an empty list and print "a\na\n" to stderr.
- Trailing new lines are always trimmed for external commands when
piping into internal commands or collecting it as a value. (Failure to
decode the output as utf-8 will keep the trailing newline for the last
binary value.) In the current nushell version, the following three code
snippets differ only in parenthesis placement, but they all also have
different outputs:
1. `1..2 | each { ^echo a }`
```
a
a
╭────────────╮
│ empty list │
╰────────────╯
```
2. `1..2 | each { (^echo a) }`
```
╭───┬───╮
│ 0 │ a │
│ 1 │ a │
╰───┴───╯
```
3. `1..2 | (each { ^echo a })`
```
╭───┬───╮
│ 0 │ a │
│ │ │
│ 1 │ a │
│ │ │
╰───┴───╯
```
But in this PR, the above snippets will all have the same output:
```
╭───┬───╮
│ 0 │ a │
│ 1 │ a │
╰───┴───╯
```
- All existing flags on `run-external` are now deprecated.
- File redirections now apply to all commands inside a code block:
```nushell
(nu -c "print -e a"; nu -c "print -e b") e> test.out
```
This gives "a\nb\n" in `test.out` and prints nothing. The same result
would happen when printing to stdout and using a `o>` file redirection.
- External command output will (almost) never be ignored, and ignoring
output must be explicit now:
```nushell
(^echo a; ^echo b)
```
This prints "a\nb\n", whereas this used to print only "b\n". This only
applies to external commands; values and internal commands not in return
position will not print anything (e.g., `(echo a; echo b)` still only
prints "b").
- `complete` now always captures stderr (`do` is not necessary).
# After Submitting
The language guide and other documentation will need to be updated.
# Description
Fixes some ignored clippy lints.
# User-Facing Changes
Changes some signatures and return types to `&dyn Command` instead of
`&Box<dyn Command`, but I believe this is only an internal change.
<!--
if this PR closes one or more issues, you can automatically link the PR
with
them by using one of the [*linking
keywords*](https://docs.github.com/en/issues/tracking-your-work-with-issues/linking-a-pull-request-to-an-issue#linking-a-pull-request-to-an-issue-using-a-keyword),
e.g.
- this PR should close #xxxx
- fixes #xxxx
you can also mention related issues, PRs or discussions!
-->
# Description
<!--
Thank you for improving Nushell. Please, check our [contributing
guide](../CONTRIBUTING.md) and talk to the core team before making major
changes.
Description of your pull request goes here. **Provide examples and/or
screenshots** if your changes affect the user experience.
-->
This PR adds a new evaluator path with callbacks to a mutable trait
object implementing a Debugger trait. The trait object can do anything,
e.g., profiling, code coverage, step debugging. Currently,
entering/leaving a block and a pipeline element is marked with
callbacks, but more callbacks can be added as necessary. Not all
callbacks need to be used by all debuggers; unused ones are simply empty
calls. A simple profiler is implemented as a proof of concept.
The debugging support is implementing by making `eval_xxx()` functions
generic depending on whether we're debugging or not. This has zero
computational overhead, but makes the binary slightly larger (see
benchmarks below). `eval_xxx()` variants called from commands (like
`eval_block_with_early_return()` in `each`) are chosen with a dynamic
dispatch for two reasons: to not grow the binary size due to duplicating
the code of many commands, and for the fact that it isn't possible
because it would make Command trait objects object-unsafe.
In the future, I hope it will be possible to allow plugin callbacks such
that users would be able to implement their profiler plugins instead of
having to recompile Nushell.
[DAP](https://microsoft.github.io/debug-adapter-protocol/) would also be
interesting to explore.
Try `help debug profile`.
## Screenshots
Basic output:

To profile with more granularity, increase the profiler depth (you'll
see that repeated `is-windows` calls take a large chunk of total time,
making it a good candidate for optimizing):

## Benchmarks
### Binary size
Binary size increase vs. main: **+40360 bytes**. _(Both built with
`--release --features=extra,dataframe`.)_
### Time
```nushell
# bench_debug.nu
use std bench
let test = {
1..100
| each {
ls | each {|row| $row.name | str length }
}
| flatten
| math avg
}
print 'debug:'
let res2 = bench { debug profile $test } --pretty
print $res2
```
```nushell
# bench_nodebug.nu
use std bench
let test = {
1..100
| each {
ls | each {|row| $row.name | str length }
}
| flatten
| math avg
}
print 'no debug:'
let res1 = bench { do $test } --pretty
print $res1
```
`cargo run --release -- bench_debug.nu` is consistently 1--2 ms slower
than `cargo run --release -- bench_nodebug.nu` due to the collection
overhead + gathering the report. This is expected. When gathering more
stuff, the overhead is obviously higher.
`cargo run --release -- bench_nodebug.nu` vs. `nu bench_nodebug.nu` I
didn't measure any difference. Both benchmarks report times between 97
and 103 ms randomly, without one being consistently higher than the
other. This suggests that at least in this particular case, when not
running any debugger, there is no runtime overhead.
## API changes
This PR adds a generic parameter to all `eval_xxx` functions that forces
you to specify whether you use the debugger. You can resolve it in two
ways:
* Use a provided helper that will figure it out for you. If you wanted
to use `eval_block(&engine_state, ...)`, call `let eval_block =
get_eval_block(&engine_state); eval_block(&engine_state, ...)`
* If you know you're in an evaluation path that doesn't need debugger
support, call `eval_block::<WithoutDebug>(&engine_state, ...)` (this is
the case of hooks, for example).
I tried to add more explanation in the docstring of `debugger_trait.rs`.
## TODO
- [x] Better profiler output to reduce spam of iterative commands like
`each`
- [x] Resolve `TODO: DEBUG` comments
- [x] Resolve unwraps
- [x] Add doc comments
- [x] Add usage and extra usage for `debug profile`, explaining all
columns
# User-Facing Changes
<!-- List of all changes that impact the user experience here. This
helps us keep track of breaking changes. -->
Hopefully none.
# Tests + Formatting
<!--
Don't forget to add tests that cover your changes.
Make sure you've run and fixed any issues with these commands:
- `cargo fmt --all -- --check` to check standard code formatting (`cargo
fmt --all` applies these changes)
- `cargo clippy --workspace -- -D warnings -D clippy::unwrap_used` to
check that you're using the standard code style
- `cargo test --workspace` to check that all tests pass (on Windows make
sure to [enable developer
mode](https://learn.microsoft.com/en-us/windows/apps/get-started/developer-mode-features-and-debugging))
- `cargo run -- -c "use std testing; testing run-tests --path
crates/nu-std"` to run the tests for the standard library
> **Note**
> from `nushell` you can also use the `toolkit` as follows
> ```bash
> use toolkit.nu # or use an `env_change` hook to activate it
automatically
> toolkit check pr
> ```
-->
# After Submitting
<!-- If your PR had any user-facing changes, update [the
documentation](https://github.com/nushell/nushell.github.io) after the
PR is merged, if necessary. This will help us keep the docs up to date.
-->