# 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
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
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.
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Finishes implementing https://github.com/nushell/nushell/issues/10598,
which asks for a spread operator in lists, in records, and when calling
commands.
# Description
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This PR will allow spreading arguments to commands (both internal and
external). It will also deprecate spreading arguments automatically when
passing to external commands.
# User-Facing Changes
<!-- List of all changes that impact the user experience here. This
helps us keep track of breaking changes. -->
- Users will be able to use `...` to spread arguments to custom/builtin
commands that have rest parameters or allow unknown arguments, or to any
external command
- If a custom command doesn't have a rest parameter and it doesn't allow
unknown arguments either, the spread operator will not be allowed
- Passing lists to external commands without `...` will work for now but
will cause a deprecation warning saying that it'll stop working in 0.91
(is 2 versions enough time?)
Here's a function to help with demonstrating some behavior:
```nushell
> def foo [ a, b, c?, d?, ...rest ] { [$a $b $c $d $rest] | to nuon }
```
You can pass a list of arguments to fill in the `rest` parameter using
`...`:
```nushell
> foo 1 2 3 4 ...[5 6]
[1, 2, 3, 4, [5, 6]]
```
If you don't use `...`, the list `[5 6]` will be treated as a single
argument:
```nushell
> foo 1 2 3 4 [5 6] # Note the double [[]]
[1, 2, 3, 4, [[5, 6]]]
```
You can omit optional parameters before the spread arguments:
```nushell
> foo 1 2 3 ...[4 5] # d is omitted here
[1, 2, 3, null, [4, 5]]
```
If you have multiple lists, you can spread them all:
```nushell
> foo 1 2 3 ...[4 5] 6 7 ...[8] ...[]
[1, 2, 3, null, [4, 5, 6, 7, 8]]
```
Here's the kind of error you get when you try to spread arguments to a
command with no rest parameter:
And this is the warning you get when you pass a list to an external now
(without `...`):
# Tests + Formatting
<!--
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Make sure you've run and fixed any issues with these commands:
- `cargo fmt --all -- --check` to check standard code formatting (`cargo
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- `cargo test --workspace` to check that all tests pass (on Windows make
sure to [enable developer
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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
> ```
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Added tests to cover the following cases:
- Spreading arguments to a command that doesn't have a rest parameter
(unexpected spread argument error)
- Spreading arguments to a command that doesn't have a rest parameter
*but* there's also a missing positional argument (missing positional
error)
- Spreading arguments to a command that doesn't have a rest parameter
but does allow unknown arguments, such as `exec` (allowed)
- Spreading a list literal containing arguments of the wrong type (parse
error)
- Spreading a non-list value, both to internal and external commands
- Having named arguments in the middle of rest arguments
- `explain`ing a command call that spreads its arguments
# After Submitting
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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.
-->
# Examples
Suppose you have multiple tables:
```nushell
let people = [[id name age]; [0 alice 100] [1 bob 200] [2 eve 300]]
let evil_twins = [[id name age]; [0 ecila 100] [-1 bob 200] [-2 eve 300]]
```
Maybe you often find yourself needing to merge multiple tables and want
a utility to do that. You could write a function like this:
```nushell
def merge_all [ ...tables ] { $tables | reduce { |it, acc| $acc | merge $it } }
```
Then you can use it like this:
```nushell
> merge_all ...([$people $evil_twins] | each { |$it| $it | select name age })
╭───┬───────┬─────╮
│ # │ name │ age │
├───┼───────┼─────┤
│ 0 │ ecila │ 100 │
│ 1 │ bob │ 200 │
│ 2 │ eve │ 300 │
╰───┴───────┴─────╯
```
Except they had duplicate columns, so now you first want to suffix every
column with a number to tell you which table the column came from. You
can make a command for that:
```nushell
def select_and_merge [ --cols: list<string>, ...tables ] {
let renamed_tables = $tables
| enumerate
| each { |it|
$it.item | select $cols | rename ...($cols | each { |col| $col + ($it.index | into string) })
};
merge_all ...$renamed_tables
}
```
And call it like this:
```nushell
> select_and_merge --cols [name age] $people $evil_twins
╭───┬───────┬──────┬───────┬──────╮
│ # │ name0 │ age0 │ name1 │ age1 │
├───┼───────┼──────┼───────┼──────┤
│ 0 │ alice │ 100 │ ecila │ 100 │
│ 1 │ bob │ 200 │ bob │ 200 │
│ 2 │ eve │ 300 │ eve │ 300 │
╰───┴───────┴──────┴───────┴──────╯
```
---
Suppose someone's made a command to search for APT packages:
```nushell
# The main command
def search-pkgs [
--install # Whether to install any packages it finds
log_level: int # Pretend it's a good idea to make this a required positional parameter
exclude?: list<string> # Packages to exclude
repositories?: list<string> # Which repositories to look in (searches in all if not given)
...pkgs # Package names to search for
] {
{ install: $install, log_level: $log_level, exclude: ($exclude | to nuon), repositories: ($repositories | to nuon), pkgs: ($pkgs | to nuon) }
}
```
It has a lot of parameters to configure it, so you might make your own
helper commands to wrap around it for specific cases. Here's one
example:
```nushell
# Only look for packages locally
def search-pkgs-local [
--install # Whether to install any packages it finds
log_level: int
exclude?: list<string> # Packages to exclude
...pkgs # Package names to search for
] {
# All required and optional positional parameters are given
search-pkgs --install=$install $log_level [] ["<local URI or something>"] ...$pkgs
}
```
And you can run it like this:
```nushell
> search-pkgs-local --install=false 5 ...["python2.7" "vim"]
╭──────────────┬──────────────────────────────╮
│ install │ false │
│ log_level │ 5 │
│ exclude │ [] │
│ repositories │ ["<local URI or something>"] │
│ pkgs │ ["python2.7", vim] │
╰──────────────┴──────────────────────────────╯
```
One thing I realized when writing this was that if we decide to not
allow passing optional arguments using the spread operator, then you can
(mis?)use the spread operator to skip optional parameters. Here, I
didn't want to give `exclude` explicitly, so I used a spread operator to
pass the packages to install. Without it, I would've needed to do
`search-pkgs-local --install=false 5 [] "python2.7" "vim"` (explicitly
pass `[]` (or `null`, in the general case) to `exclude`). There are
probably more idiomatic ways to do this, but I just thought it was
something interesting.
If you're a virologist of the [xkcd](https://xkcd.com/350/) kind,
another helper command you might make is this:
```nushell
# Install any packages it finds
def live-dangerously [ ...pkgs ] {
# One optional argument was given (exclude), while another was not (repositories)
search-pkgs 0 [] ...$pkgs --install # Flags can go after spread arguments
}
```
Running it:
```nushell
> live-dangerously "git" "*vi*" # *vi* because I don't feel like typing out vim and neovim
╭──────────────┬─────────────╮
│ install │ true │
│ log_level │ 0 │
│ exclude │ [] │
│ repositories │ null │
│ pkgs │ [git, *vi*] │
╰──────────────┴─────────────╯
```
Here's an example that uses the spread operator more than once within
the same command call:
```nushell
let extras = [ chrome firefox python java git ]
def search-pkgs-curated [ ...pkgs ] {
(search-pkgs
1
[emacs]
["example.com", "foo.com"]
vim # A must for everyone!
...($pkgs | filter { |p| not ($p | str contains "*") }) # Remove packages with globs
python # Good tool to have
...$extras
--install=false
python3) # I forget, did I already put Python in extras?
}
```
Running it:
```nushell
> search-pkgs-curated "git" "*vi*"
╭──────────────┬───────────────────────────────────────────────────────────────────╮
│ install │ false │
│ log_level │ 1 │
│ exclude │ [emacs] │
│ repositories │ [example.com, foo.com] │
│ pkgs │ [vim, git, python, chrome, firefox, python, java, git, "python3"] │
╰──────────────┴───────────────────────────────────────────────────────────────────╯
```
# Description
* All output of `scope` commands is sorted by the "name" column. (`scope
externs` and some other commands had entries in a weird/random order)
* The output of `scope externs` does not have extra newlines (that was
due to wrong usage creation of known externals)
Continuation of #8229 and #8326
# Description
The `ShellError` enum at the moment is kind of messy.
Many variants are basic tuple structs where you always have to reference
the implementation with its macro invocation to know which field serves
which purpose.
Furthermore we have both variants that are kind of redundant or either
overly broad to be useful for the user to match on or overly specific
with few uses.
So I set out to start fixing the lacking documentation and naming to
make it feasible to critically review the individual usages and fix
those.
Furthermore we can decide to join or split up variants that don't seem
to be fit for purpose.
# Call to action
**Everyone:** Feel free to add review comments if you spot inconsistent
use of `ShellError` variants.
# User-Facing Changes
(None now, end goal more explicit and consistent error messages)
# Tests + Formatting
(No additional tests needed so far)
# Commits (so far)
- Remove `ShellError::FeatureNotEnabled`
- Name fields on `SE::ExternalNotSupported`
- Name field on `SE::InvalidProbability`
- Name fields on `SE::NushellFailed` variants
- Remove unused `SE::NushellFailedSpannedHelp`
- Name field on `SE::VariableNotFoundAtRuntime`
- Name fields on `SE::EnvVarNotFoundAtRuntime`
- Name fields on `SE::ModuleNotFoundAtRuntime`
- Remove usused `ModuleOrOverlayNotFoundAtRuntime`
- Name fields on `SE::OverlayNotFoundAtRuntime`
- Name field on `SE::NotFound`
* WIP: Start laying overlays
* Rename Overlay->Module; Start adding overlay
* Revamp adding overlay
* Add overlay add tests; Disable debug print
* Fix overlay add; Add overlay remove
* Add overlay remove tests
* Add missing overlay remove file
* Add overlay list command
* (WIP?) Enable overlays for env vars
* Move OverlayFrames to ScopeFrames
* (WIP) Move everything to overlays only
ScopeFrame contains nothing but overlays now
* Fix predecls
* Fix wrong overlay id translation and aliases
* Fix broken env lookup logic
* Remove TODOs
* Add overlay add + remove for environment
* Add a few overlay tests; Fix overlay add name
* Some cleanup; Fix overlay add/remove names
* Clippy
* Fmt
* Remove walls of comments
* List overlays from stack; Add debugging flag
Currently, the engine state ordering is somehow broken.
* Fix (?) overlay list test
* Fix tests on Windows
* Fix activated overlay ordering
* Check for active overlays equality in overlay list
This removes the -p flag: Either both parser and engine will have the
same overlays, or the command will fail.
* Add merging on overlay remove
* Change help message and comment
* Add some remove-merge/discard tests
* (WIP) Track removed overlays properly
* Clippy; Fmt
* Fix getting last overlay; Fix predecls in overlays
* Remove merging; Fix re-add overwriting stuff
Also some error message tweaks.
* Fix overlay error in the engine
* Update variable_completions.rs
* Adds flags and optional arguments to view-source (#5446)
* added flags and optional arguments to view-source
* removed redundant code
* removed redundant code
* fmt
* fix bug in shell_integration (#5450)
* fix bug in shell_integration
* add some comments
* enable cd to work with directory abbreviations (#5452)
* enable cd to work with abbreviations
* add abbreviation example
* fix tests
* make it configurable
* make cd recornize symblic link (#5454)
* implement seq char command to generate single character sequence (#5453)
* add tmp code
* add seq char command
* Add split number flag in `split row` (#5434)
Signed-off-by: Yuheng Su <gipsyh.icu@gmail.com>
* Add two more overlay tests
* Add ModuleId to OverlayFrame
* Fix env conversion accidentally activating overlay
It activated overlay from permanent state prematurely which would
cause `overlay add` to misbehave.
* Remove unused parameter; Add overlay list test
* Remove added traces
* Add overlay commands examples
* Modify TODO
* Fix $nu.scope iteration
* Disallow removing default overlay
* Refactor some parser errors
* Remove last overlay if no argument
* Diversify overlay examples
* Make it possible to update overlay's module
In case the origin module updates, the overlay add loads the new module,
makes it overlay's origin and applies the changes. Before, it was
impossible to update the overlay if the module changed.
Co-authored-by: JT <547158+jntrnr@users.noreply.github.com>
Co-authored-by: pwygab <88221256+merelymyself@users.noreply.github.com>
Co-authored-by: Darren Schroeder <343840+fdncred@users.noreply.github.com>
Co-authored-by: WindSoilder <WindSoilder@outlook.com>
Co-authored-by: Yuheng Su <gipsyh.icu@gmail.com>
Prior to this change we would recover the names for known
externals by looking up the span in the engine state. This would fail
when using an alias for two reasons:
1. In cases where we don't have a subcommand, like this:
```
>>> extern bat [filename: string]
>>> alias b = bat
>>> bat some_file
'b' is not recognized as an internal or external command,
operable program or batch file.
```
The problem is that after alias expansion, we replace the span of the
expanded name with the original alias (this is done to alleviate
non-related issues). The span contents we look up therefore contain `b`,
the alias, instead of the expanded command name.
2. In cases where there's a subcommand:
```
>>> alias g = git
>>> g push
thread 'main' panicked at 'internal error: span missing in file contents cache', crates\nu-protocol\src\engine\engine_state.rs:474:9
note: run with `RUST_BACKTRACE=1` environment variable to display a
backtrace
```
In this case, the span in call starts where the expansion for the `g`
alias is defined and end after `push` on the last command entered. This
is not a proper span and causes a panic when we try to look it up. Note
that this is the case for all expanded aliases that involve a
subcommand, but we never actually try to retrieve the contents for that
span in other cases.
Anyway, the new way of looking up the name is arguably cleaner
regardless of the issues mentioned above. But it's nice that it fixes
them too.
Co-authored-by: Hristo Filaretov <h.filaretov@protonmail.com>
* Initial implementation of ordered call args
* Run cargo fmt
* Fix some clippy lints
* Add positional len and nth
* Cargo fmt
* Remove more old nth calls
* Good ole rustfmt
* Add named len
Co-authored-by: Hristo Filaretov <h.filaretov@protonmail.com>
