nushell/tests/repl/test_known_external.rs

140 lines
3.3 KiB
Rust
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use crate::repl::tests::{fail_test, run_test, run_test_contains, TestResult};
use std::process::Command;
// cargo version prints a string of the form:
// cargo 1.60.0 (d1fd9fe2c 2022-03-01)
#[test]
fn known_external_runs() -> TestResult {
run_test_contains(r#"extern "cargo version" []; cargo version"#, "cargo")
}
#[test]
fn known_external_unknown_flag() -> TestResult {
run_test_contains(r#"extern "cargo" []; cargo --version"#, "cargo")
}
/// GitHub issues #5179, #4618
#[test]
fn known_external_alias() -> TestResult {
run_test_contains(
r#"extern "cargo version" []; alias cv = cargo version; cv"#,
"cargo",
)
}
/// GitHub issues #5179, #4618
#[test]
fn known_external_subcommand_alias() -> TestResult {
run_test_contains(
r#"extern "cargo version" []; alias c = cargo; c version"#,
"cargo",
)
}
#[test]
fn known_external_complex_unknown_args() -> TestResult {
run_test_contains(
"extern echo []; echo foo -b -as -9 --abc -- -Dxmy=AKOO - bar",
"foo -b -as -9 --abc -- -Dxmy=AKOO - bar",
)
}
#[test]
fn known_external_from_module() -> TestResult {
run_test_contains(
r#"module spam {
export extern echo []
}
use spam echo
echo foo -b -as -9 --abc -- -Dxmy=AKOO - bar
"#,
"foo -b -as -9 --abc -- -Dxmy=AKOO - bar",
)
}
#[test]
fn known_external_short_flag_batch_arg_allowed() -> TestResult {
run_test_contains("extern echo [-a, -b: int]; echo -ab 10", "-b 10")
}
#[test]
fn known_external_short_flag_batch_arg_disallowed() -> TestResult {
fail_test(
"extern echo [-a: int, -b]; echo -ab 10",
"last flag can take args",
)
}
#[test]
fn known_external_short_flag_batch_multiple_args() -> TestResult {
fail_test(
"extern echo [-a: int, -b: int]; echo -ab 10 20",
"last flag can take args",
)
}
#[test]
fn known_external_missing_positional() -> TestResult {
fail_test("extern echo [a]; echo", "missing_positional")
}
#[test]
fn known_external_type_mismatch() -> TestResult {
fail_test("extern echo [a: int]; echo 1.234", "mismatch")
}
#[test]
fn known_external_missing_flag_param() -> TestResult {
fail_test(
"extern echo [--foo: string]; echo --foo",
"missing_flag_param",
)
}
#[test]
fn known_external_misc_values() -> TestResult {
run_test(
r#"
let x = 'abc'
Allow spreading arguments to commands (#11289) <!-- 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! --> Finishes implementing https://github.com/nushell/nushell/issues/10598, which asks for a spread operator in lists, in records, and when calling commands. # 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 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: ![image](https://github.com/nushell/nushell/assets/45539777/93faceae-00eb-4e59-ac3f-17f98436e6e4) And this is the warning you get when you pass a list to an external now (without `...`): ![image](https://github.com/nushell/nushell/assets/45539777/d368f590-201e-49fb-8b20-68476ced415e) # 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 > ``` --> 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 <!-- 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. --> # 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"] │ ╰──────────────┴───────────────────────────────────────────────────────────────────╯ ```
2023-12-28 08:43:20 +01:00
extern echo [...args]
echo $x ...[ a b c ]
"#,
"abc a b c",
)
}
/// GitHub issue #7822
#[test]
fn known_external_subcommand_from_module() -> TestResult {
Rewrite run_external.rs (#12921) This PR is a complete rewrite of `run_external.rs`. The main goal of the rewrite is improving readability, but it also fixes some bugs related to argument handling and the PATH variable (fixes https://github.com/nushell/nushell/issues/6011). I'll discuss some technical details to make reviewing easier. ## Argument handling Quoting arguments for external commands is hard. Like, *really* hard. We've had more than a dozen issues and PRs dedicated to quoting arguments (see Appendix) but the current implementation is still buggy. Here's a demonstration of the buggy behavior: ```nu let foo = "'bar'" ^touch $foo # This creates a file named `bar`, but it should be `'bar'` ^touch ...[ "'bar'" ] # Same ``` I'll describe how this PR deals with argument handling. First, we'll introduce the concept of **bare strings**. Bare strings are **string literals** that are either **unquoted** or **quoted by backticks** [^1]. Strings within a list literal are NOT considered bare strings, even if they are unquoted or quoted by backticks. When a bare string is used as an argument to external process, we need to perform tilde-expansion, glob-expansion, and inner-quotes-removal, in that order. "Inner-quotes-removal" means transforming from `--option="value"` into `--option=value`. ## `.bat` files and CMD built-ins On Windows, `.bat` files and `.cmd` files are considered executable, but they need `CMD.exe` as the interpreter. The Rust standard library supports running `.bat` files directly and will spawn `CMD.exe` under the hood (see [documentation](https://doc.rust-lang.org/std/process/index.html#windows-argument-splitting)). However, other extensions are not supported [^2]. Nushell also supports a selected number of CMD built-ins. The problem with CMD is that it uses a different set of quoting rules. Correctly quoting for CMD requires using [Command::raw_arg()](https://doc.rust-lang.org/std/os/windows/process/trait.CommandExt.html#tymethod.raw_arg) and manually quoting CMD special characters, on top of quoting from the Nushell side. ~~I decided that this is too complex and chose to reject special characters in CMD built-ins instead [^3]. Hopefully this will not affact real-world use cases.~~ I've implemented escaping that works reasonably well. ## `which-support` feature The `which` crate is now a hard dependency of `nu-command`, making the `which-support` feature essentially useless. The `which` crate is already a hard dependency of `nu-cli`, and we should consider removing the `which-support` feature entirely. ## Appendix Here's a list of quoting-related issues and PRs in rough chronological order. * https://github.com/nushell/nushell/issues/4609 * https://github.com/nushell/nushell/issues/4631 * https://github.com/nushell/nushell/issues/4601 * https://github.com/nushell/nushell/pull/5846 * https://github.com/nushell/nushell/issues/5978 * https://github.com/nushell/nushell/pull/6014 * https://github.com/nushell/nushell/issues/6154 * https://github.com/nushell/nushell/pull/6161 * https://github.com/nushell/nushell/issues/6399 * https://github.com/nushell/nushell/pull/6420 * https://github.com/nushell/nushell/pull/6426 * https://github.com/nushell/nushell/issues/6465 * https://github.com/nushell/nushell/issues/6559 * https://github.com/nushell/nushell/pull/6560 [^1]: The idea that backtick-quoted strings act like bare strings was introduced by Kubouch and briefly mentioned in [the language reference](https://www.nushell.sh/lang-guide/chapters/strings_and_text.html#backtick-quotes). [^2]: The documentation also said "running .bat scripts in this way may be removed in the future and so should not be relied upon", which is another reason to move away from this. But again, quoting for CMD is hard. [^3]: If anyone wants to try, the best resource I found on the topic is [this](https://daviddeley.com/autohotkey/parameters/parameters.htm).
2024-05-23 04:05:27 +02:00
let output = Command::new("cargo").arg("add").arg("-h").output()?;
run_test(
r#"
module cargo {
Rewrite run_external.rs (#12921) This PR is a complete rewrite of `run_external.rs`. The main goal of the rewrite is improving readability, but it also fixes some bugs related to argument handling and the PATH variable (fixes https://github.com/nushell/nushell/issues/6011). I'll discuss some technical details to make reviewing easier. ## Argument handling Quoting arguments for external commands is hard. Like, *really* hard. We've had more than a dozen issues and PRs dedicated to quoting arguments (see Appendix) but the current implementation is still buggy. Here's a demonstration of the buggy behavior: ```nu let foo = "'bar'" ^touch $foo # This creates a file named `bar`, but it should be `'bar'` ^touch ...[ "'bar'" ] # Same ``` I'll describe how this PR deals with argument handling. First, we'll introduce the concept of **bare strings**. Bare strings are **string literals** that are either **unquoted** or **quoted by backticks** [^1]. Strings within a list literal are NOT considered bare strings, even if they are unquoted or quoted by backticks. When a bare string is used as an argument to external process, we need to perform tilde-expansion, glob-expansion, and inner-quotes-removal, in that order. "Inner-quotes-removal" means transforming from `--option="value"` into `--option=value`. ## `.bat` files and CMD built-ins On Windows, `.bat` files and `.cmd` files are considered executable, but they need `CMD.exe` as the interpreter. The Rust standard library supports running `.bat` files directly and will spawn `CMD.exe` under the hood (see [documentation](https://doc.rust-lang.org/std/process/index.html#windows-argument-splitting)). However, other extensions are not supported [^2]. Nushell also supports a selected number of CMD built-ins. The problem with CMD is that it uses a different set of quoting rules. Correctly quoting for CMD requires using [Command::raw_arg()](https://doc.rust-lang.org/std/os/windows/process/trait.CommandExt.html#tymethod.raw_arg) and manually quoting CMD special characters, on top of quoting from the Nushell side. ~~I decided that this is too complex and chose to reject special characters in CMD built-ins instead [^3]. Hopefully this will not affact real-world use cases.~~ I've implemented escaping that works reasonably well. ## `which-support` feature The `which` crate is now a hard dependency of `nu-command`, making the `which-support` feature essentially useless. The `which` crate is already a hard dependency of `nu-cli`, and we should consider removing the `which-support` feature entirely. ## Appendix Here's a list of quoting-related issues and PRs in rough chronological order. * https://github.com/nushell/nushell/issues/4609 * https://github.com/nushell/nushell/issues/4631 * https://github.com/nushell/nushell/issues/4601 * https://github.com/nushell/nushell/pull/5846 * https://github.com/nushell/nushell/issues/5978 * https://github.com/nushell/nushell/pull/6014 * https://github.com/nushell/nushell/issues/6154 * https://github.com/nushell/nushell/pull/6161 * https://github.com/nushell/nushell/issues/6399 * https://github.com/nushell/nushell/pull/6420 * https://github.com/nushell/nushell/pull/6426 * https://github.com/nushell/nushell/issues/6465 * https://github.com/nushell/nushell/issues/6559 * https://github.com/nushell/nushell/pull/6560 [^1]: The idea that backtick-quoted strings act like bare strings was introduced by Kubouch and briefly mentioned in [the language reference](https://www.nushell.sh/lang-guide/chapters/strings_and_text.html#backtick-quotes). [^2]: The documentation also said "running .bat scripts in this way may be removed in the future and so should not be relied upon", which is another reason to move away from this. But again, quoting for CMD is hard. [^3]: If anyone wants to try, the best resource I found on the topic is [this](https://daviddeley.com/autohotkey/parameters/parameters.htm).
2024-05-23 04:05:27 +02:00
export extern add []
};
use cargo;
Rewrite run_external.rs (#12921) This PR is a complete rewrite of `run_external.rs`. The main goal of the rewrite is improving readability, but it also fixes some bugs related to argument handling and the PATH variable (fixes https://github.com/nushell/nushell/issues/6011). I'll discuss some technical details to make reviewing easier. ## Argument handling Quoting arguments for external commands is hard. Like, *really* hard. We've had more than a dozen issues and PRs dedicated to quoting arguments (see Appendix) but the current implementation is still buggy. Here's a demonstration of the buggy behavior: ```nu let foo = "'bar'" ^touch $foo # This creates a file named `bar`, but it should be `'bar'` ^touch ...[ "'bar'" ] # Same ``` I'll describe how this PR deals with argument handling. First, we'll introduce the concept of **bare strings**. Bare strings are **string literals** that are either **unquoted** or **quoted by backticks** [^1]. Strings within a list literal are NOT considered bare strings, even if they are unquoted or quoted by backticks. When a bare string is used as an argument to external process, we need to perform tilde-expansion, glob-expansion, and inner-quotes-removal, in that order. "Inner-quotes-removal" means transforming from `--option="value"` into `--option=value`. ## `.bat` files and CMD built-ins On Windows, `.bat` files and `.cmd` files are considered executable, but they need `CMD.exe` as the interpreter. The Rust standard library supports running `.bat` files directly and will spawn `CMD.exe` under the hood (see [documentation](https://doc.rust-lang.org/std/process/index.html#windows-argument-splitting)). However, other extensions are not supported [^2]. Nushell also supports a selected number of CMD built-ins. The problem with CMD is that it uses a different set of quoting rules. Correctly quoting for CMD requires using [Command::raw_arg()](https://doc.rust-lang.org/std/os/windows/process/trait.CommandExt.html#tymethod.raw_arg) and manually quoting CMD special characters, on top of quoting from the Nushell side. ~~I decided that this is too complex and chose to reject special characters in CMD built-ins instead [^3]. Hopefully this will not affact real-world use cases.~~ I've implemented escaping that works reasonably well. ## `which-support` feature The `which` crate is now a hard dependency of `nu-command`, making the `which-support` feature essentially useless. The `which` crate is already a hard dependency of `nu-cli`, and we should consider removing the `which-support` feature entirely. ## Appendix Here's a list of quoting-related issues and PRs in rough chronological order. * https://github.com/nushell/nushell/issues/4609 * https://github.com/nushell/nushell/issues/4631 * https://github.com/nushell/nushell/issues/4601 * https://github.com/nushell/nushell/pull/5846 * https://github.com/nushell/nushell/issues/5978 * https://github.com/nushell/nushell/pull/6014 * https://github.com/nushell/nushell/issues/6154 * https://github.com/nushell/nushell/pull/6161 * https://github.com/nushell/nushell/issues/6399 * https://github.com/nushell/nushell/pull/6420 * https://github.com/nushell/nushell/pull/6426 * https://github.com/nushell/nushell/issues/6465 * https://github.com/nushell/nushell/issues/6559 * https://github.com/nushell/nushell/pull/6560 [^1]: The idea that backtick-quoted strings act like bare strings was introduced by Kubouch and briefly mentioned in [the language reference](https://www.nushell.sh/lang-guide/chapters/strings_and_text.html#backtick-quotes). [^2]: The documentation also said "running .bat scripts in this way may be removed in the future and so should not be relied upon", which is another reason to move away from this. But again, quoting for CMD is hard. [^3]: If anyone wants to try, the best resource I found on the topic is [this](https://daviddeley.com/autohotkey/parameters/parameters.htm).
2024-05-23 04:05:27 +02:00
cargo add -h
"#,
String::from_utf8(output.stdout)?.trim(),
)
}
/// GitHub issue #7822
#[test]
fn known_external_aliased_subcommand_from_module() -> TestResult {
Rewrite run_external.rs (#12921) This PR is a complete rewrite of `run_external.rs`. The main goal of the rewrite is improving readability, but it also fixes some bugs related to argument handling and the PATH variable (fixes https://github.com/nushell/nushell/issues/6011). I'll discuss some technical details to make reviewing easier. ## Argument handling Quoting arguments for external commands is hard. Like, *really* hard. We've had more than a dozen issues and PRs dedicated to quoting arguments (see Appendix) but the current implementation is still buggy. Here's a demonstration of the buggy behavior: ```nu let foo = "'bar'" ^touch $foo # This creates a file named `bar`, but it should be `'bar'` ^touch ...[ "'bar'" ] # Same ``` I'll describe how this PR deals with argument handling. First, we'll introduce the concept of **bare strings**. Bare strings are **string literals** that are either **unquoted** or **quoted by backticks** [^1]. Strings within a list literal are NOT considered bare strings, even if they are unquoted or quoted by backticks. When a bare string is used as an argument to external process, we need to perform tilde-expansion, glob-expansion, and inner-quotes-removal, in that order. "Inner-quotes-removal" means transforming from `--option="value"` into `--option=value`. ## `.bat` files and CMD built-ins On Windows, `.bat` files and `.cmd` files are considered executable, but they need `CMD.exe` as the interpreter. The Rust standard library supports running `.bat` files directly and will spawn `CMD.exe` under the hood (see [documentation](https://doc.rust-lang.org/std/process/index.html#windows-argument-splitting)). However, other extensions are not supported [^2]. Nushell also supports a selected number of CMD built-ins. The problem with CMD is that it uses a different set of quoting rules. Correctly quoting for CMD requires using [Command::raw_arg()](https://doc.rust-lang.org/std/os/windows/process/trait.CommandExt.html#tymethod.raw_arg) and manually quoting CMD special characters, on top of quoting from the Nushell side. ~~I decided that this is too complex and chose to reject special characters in CMD built-ins instead [^3]. Hopefully this will not affact real-world use cases.~~ I've implemented escaping that works reasonably well. ## `which-support` feature The `which` crate is now a hard dependency of `nu-command`, making the `which-support` feature essentially useless. The `which` crate is already a hard dependency of `nu-cli`, and we should consider removing the `which-support` feature entirely. ## Appendix Here's a list of quoting-related issues and PRs in rough chronological order. * https://github.com/nushell/nushell/issues/4609 * https://github.com/nushell/nushell/issues/4631 * https://github.com/nushell/nushell/issues/4601 * https://github.com/nushell/nushell/pull/5846 * https://github.com/nushell/nushell/issues/5978 * https://github.com/nushell/nushell/pull/6014 * https://github.com/nushell/nushell/issues/6154 * https://github.com/nushell/nushell/pull/6161 * https://github.com/nushell/nushell/issues/6399 * https://github.com/nushell/nushell/pull/6420 * https://github.com/nushell/nushell/pull/6426 * https://github.com/nushell/nushell/issues/6465 * https://github.com/nushell/nushell/issues/6559 * https://github.com/nushell/nushell/pull/6560 [^1]: The idea that backtick-quoted strings act like bare strings was introduced by Kubouch and briefly mentioned in [the language reference](https://www.nushell.sh/lang-guide/chapters/strings_and_text.html#backtick-quotes). [^2]: The documentation also said "running .bat scripts in this way may be removed in the future and so should not be relied upon", which is another reason to move away from this. But again, quoting for CMD is hard. [^3]: If anyone wants to try, the best resource I found on the topic is [this](https://daviddeley.com/autohotkey/parameters/parameters.htm).
2024-05-23 04:05:27 +02:00
let output = Command::new("cargo").arg("add").arg("-h").output()?;
run_test(
r#"
module cargo {
Rewrite run_external.rs (#12921) This PR is a complete rewrite of `run_external.rs`. The main goal of the rewrite is improving readability, but it also fixes some bugs related to argument handling and the PATH variable (fixes https://github.com/nushell/nushell/issues/6011). I'll discuss some technical details to make reviewing easier. ## Argument handling Quoting arguments for external commands is hard. Like, *really* hard. We've had more than a dozen issues and PRs dedicated to quoting arguments (see Appendix) but the current implementation is still buggy. Here's a demonstration of the buggy behavior: ```nu let foo = "'bar'" ^touch $foo # This creates a file named `bar`, but it should be `'bar'` ^touch ...[ "'bar'" ] # Same ``` I'll describe how this PR deals with argument handling. First, we'll introduce the concept of **bare strings**. Bare strings are **string literals** that are either **unquoted** or **quoted by backticks** [^1]. Strings within a list literal are NOT considered bare strings, even if they are unquoted or quoted by backticks. When a bare string is used as an argument to external process, we need to perform tilde-expansion, glob-expansion, and inner-quotes-removal, in that order. "Inner-quotes-removal" means transforming from `--option="value"` into `--option=value`. ## `.bat` files and CMD built-ins On Windows, `.bat` files and `.cmd` files are considered executable, but they need `CMD.exe` as the interpreter. The Rust standard library supports running `.bat` files directly and will spawn `CMD.exe` under the hood (see [documentation](https://doc.rust-lang.org/std/process/index.html#windows-argument-splitting)). However, other extensions are not supported [^2]. Nushell also supports a selected number of CMD built-ins. The problem with CMD is that it uses a different set of quoting rules. Correctly quoting for CMD requires using [Command::raw_arg()](https://doc.rust-lang.org/std/os/windows/process/trait.CommandExt.html#tymethod.raw_arg) and manually quoting CMD special characters, on top of quoting from the Nushell side. ~~I decided that this is too complex and chose to reject special characters in CMD built-ins instead [^3]. Hopefully this will not affact real-world use cases.~~ I've implemented escaping that works reasonably well. ## `which-support` feature The `which` crate is now a hard dependency of `nu-command`, making the `which-support` feature essentially useless. The `which` crate is already a hard dependency of `nu-cli`, and we should consider removing the `which-support` feature entirely. ## Appendix Here's a list of quoting-related issues and PRs in rough chronological order. * https://github.com/nushell/nushell/issues/4609 * https://github.com/nushell/nushell/issues/4631 * https://github.com/nushell/nushell/issues/4601 * https://github.com/nushell/nushell/pull/5846 * https://github.com/nushell/nushell/issues/5978 * https://github.com/nushell/nushell/pull/6014 * https://github.com/nushell/nushell/issues/6154 * https://github.com/nushell/nushell/pull/6161 * https://github.com/nushell/nushell/issues/6399 * https://github.com/nushell/nushell/pull/6420 * https://github.com/nushell/nushell/pull/6426 * https://github.com/nushell/nushell/issues/6465 * https://github.com/nushell/nushell/issues/6559 * https://github.com/nushell/nushell/pull/6560 [^1]: The idea that backtick-quoted strings act like bare strings was introduced by Kubouch and briefly mentioned in [the language reference](https://www.nushell.sh/lang-guide/chapters/strings_and_text.html#backtick-quotes). [^2]: The documentation also said "running .bat scripts in this way may be removed in the future and so should not be relied upon", which is another reason to move away from this. But again, quoting for CMD is hard. [^3]: If anyone wants to try, the best resource I found on the topic is [this](https://daviddeley.com/autohotkey/parameters/parameters.htm).
2024-05-23 04:05:27 +02:00
export extern add []
};
use cargo;
Rewrite run_external.rs (#12921) This PR is a complete rewrite of `run_external.rs`. The main goal of the rewrite is improving readability, but it also fixes some bugs related to argument handling and the PATH variable (fixes https://github.com/nushell/nushell/issues/6011). I'll discuss some technical details to make reviewing easier. ## Argument handling Quoting arguments for external commands is hard. Like, *really* hard. We've had more than a dozen issues and PRs dedicated to quoting arguments (see Appendix) but the current implementation is still buggy. Here's a demonstration of the buggy behavior: ```nu let foo = "'bar'" ^touch $foo # This creates a file named `bar`, but it should be `'bar'` ^touch ...[ "'bar'" ] # Same ``` I'll describe how this PR deals with argument handling. First, we'll introduce the concept of **bare strings**. Bare strings are **string literals** that are either **unquoted** or **quoted by backticks** [^1]. Strings within a list literal are NOT considered bare strings, even if they are unquoted or quoted by backticks. When a bare string is used as an argument to external process, we need to perform tilde-expansion, glob-expansion, and inner-quotes-removal, in that order. "Inner-quotes-removal" means transforming from `--option="value"` into `--option=value`. ## `.bat` files and CMD built-ins On Windows, `.bat` files and `.cmd` files are considered executable, but they need `CMD.exe` as the interpreter. The Rust standard library supports running `.bat` files directly and will spawn `CMD.exe` under the hood (see [documentation](https://doc.rust-lang.org/std/process/index.html#windows-argument-splitting)). However, other extensions are not supported [^2]. Nushell also supports a selected number of CMD built-ins. The problem with CMD is that it uses a different set of quoting rules. Correctly quoting for CMD requires using [Command::raw_arg()](https://doc.rust-lang.org/std/os/windows/process/trait.CommandExt.html#tymethod.raw_arg) and manually quoting CMD special characters, on top of quoting from the Nushell side. ~~I decided that this is too complex and chose to reject special characters in CMD built-ins instead [^3]. Hopefully this will not affact real-world use cases.~~ I've implemented escaping that works reasonably well. ## `which-support` feature The `which` crate is now a hard dependency of `nu-command`, making the `which-support` feature essentially useless. The `which` crate is already a hard dependency of `nu-cli`, and we should consider removing the `which-support` feature entirely. ## Appendix Here's a list of quoting-related issues and PRs in rough chronological order. * https://github.com/nushell/nushell/issues/4609 * https://github.com/nushell/nushell/issues/4631 * https://github.com/nushell/nushell/issues/4601 * https://github.com/nushell/nushell/pull/5846 * https://github.com/nushell/nushell/issues/5978 * https://github.com/nushell/nushell/pull/6014 * https://github.com/nushell/nushell/issues/6154 * https://github.com/nushell/nushell/pull/6161 * https://github.com/nushell/nushell/issues/6399 * https://github.com/nushell/nushell/pull/6420 * https://github.com/nushell/nushell/pull/6426 * https://github.com/nushell/nushell/issues/6465 * https://github.com/nushell/nushell/issues/6559 * https://github.com/nushell/nushell/pull/6560 [^1]: The idea that backtick-quoted strings act like bare strings was introduced by Kubouch and briefly mentioned in [the language reference](https://www.nushell.sh/lang-guide/chapters/strings_and_text.html#backtick-quotes). [^2]: The documentation also said "running .bat scripts in this way may be removed in the future and so should not be relied upon", which is another reason to move away from this. But again, quoting for CMD is hard. [^3]: If anyone wants to try, the best resource I found on the topic is [this](https://daviddeley.com/autohotkey/parameters/parameters.htm).
2024-05-23 04:05:27 +02:00
alias cc = cargo add;
cc -h
"#,
String::from_utf8(output.stdout)?.trim(),
)
}