Command in run_make_support::command - Rust
Description: This is a custom command wrapper that simplifies working with commands and makes it easier to ensure that we check the exit status of executed processes.

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## Command

# Struct Command

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    pub struct Command {
        cmd: Command,
        stdin_buf: Option<Box<[u8]>>,
        stdin: Option<Stdio>,
        stdout: Option<Stdio>,
        stderr: Option<Stdio>,
        drop_bomb: DropBomb,
        already_executed: bool,
        context: String,
    }

Expand description

This is a custom command wrapper that simplifies working with commands and makes it easier to ensure that we check the exit status of executed processes.

## §A `Command` must be executed exactly once

A `Command` is armed by a [`DropBomb`] on construction to enforce that it will be executed. If a `Command` is constructed but never executed, the drop bomb will explode and cause the test to panic. Execution methods `run` and `run_fail` will defuse the drop bomb. A test containing constructed but never executed commands is dangerous because it can give a false sense of confidence.

Each `Command` invocation can also only be executed once, because we want to enforce `std{in,out,err}` config via `std::process::Stdio` but `std::process::Stdio` is not cloneable.

In this sense, `Command` exhibits linear type semantics but enforced at run-time.

## Fields§

§`cmd: Command`§`stdin_buf: Option<Box<[u8]>>`§`stdin: Option<Stdio>`§`stdout: Option<Stdio>`§`stderr: Option<Stdio>`§`drop_bomb: DropBomb`§`already_executed: bool`§`context: String`

## Implementations§

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### impl Command

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#### pub fn new<P: AsRef<OsStr>>(program: P) -> Self

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#### pub(crate) fn into_raw_command(self) -> Command

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#### pub(crate) fn get_context(&self) -> &str

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#### pub fn context(&mut self, ctx: &str) -> &mut Self

Appends context to the command, to provide a better error message if the command fails.

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#### pub fn stdin_buf<I: AsRef<[u8]>>(&mut self, input: I) -> &mut Self

Specify a stdin input buffer. This is a convenience helper,

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#### pub fn stdin<T: Into<Stdio>>(&mut self, cfg: T) -> &mut Self

Configuration for the child process’s standard input (stdin) handle.

See `std::process::Command::stdin`.

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#### pub fn stdout<T: Into<Stdio>>(&mut self, cfg: T) -> &mut Self

Configuration for the child process’s standard output (stdout) handle.

See `std::process::Command::stdout`.

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#### pub fn stderr<T: Into<Stdio>>(&mut self, cfg: T) -> &mut Self

Configuration for the child process’s standard error (stderr) handle.

See `std::process::Command::stderr`.

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#### pub fn env<K, V>(&mut self, key: K, value: V) -> &mut Self
where K: AsRef<OsStr>, V: AsRef<OsStr>,

Specify an environment variable.

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#### pub fn env_remove<K>(&mut self, key: K) -> &mut Self
where K: AsRef<OsStr>,

Remove an environmental variable.

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#### pub fn arg<S>(&mut self, arg: S) -> &mut Self
where S: AsRef<OsStr>,

Generic command argument provider. Prefer specific helper methods if possible. Note that for some executables, arguments might be platform specific. For C/C++ compilers, arguments might be platform and compiler specific.

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#### pub fn args<S, V>(&mut self, args: V) -> &mut Self
where S: AsRef<OsStr>, V: AsRef<[S]>,

Generic command arguments provider. Prefer specific helper methods if possible. Note that for some executables, arguments might be platform specific. For C/C++ compilers, arguments might be platform and compiler specific.

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#### pub fn inspect<I>(&self, inspector: I) -> &Self
where I: FnOnce(&StdCommand),

Inspect what the underlying `std::process::Command` is up to the current construction.

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#### pub fn current_dir<P: AsRef<Path>>(&mut self, path: P) -> &mut Self

Set the path where the command will be run.

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#### pub fn set_aux_fd<F: Into<OwnedFd>>( &mut self, new_fd: RawFd, fd: F, ) -> &mut Self

Set an auxiliary stream passed to the process, besides the stdio streams.

##### §Notes

Use with caution! Ideally, only set one aux fd; if there are multiple, their old `fd` may overlap with another’s `new_fd`, and may break. The caller must make sure this is not the case. This function is only “safe” because the safety requirements are practically not possible to uphold.

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#### pub fn run(&mut self) -> CompletedProcess

Run the constructed command and assert that it is successfully run.

By default, std{in,out,err} are `Stdio::piped()`.

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#### pub fn run_fail(&mut self) -> CompletedProcess

Run the constructed command and assert that it does not successfully run.

By default, std{in,out,err} are `Stdio::piped()`.

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#### pub fn run_unchecked(&mut self) -> CompletedProcess

Run the command but do not check its exit status. Only use if you explicitly don’t care about the exit status.

Prefer to use `Self::run` and `Self::run_fail` whenever possible.

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#### fn command_output(&mut self) -> CompletedProcess

## Trait Implementations§

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### impl Debug for Command

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#### fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter. Read more

## Auto Trait Implementations§

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### impl !RefUnwindSafe for Command

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### impl !UnwindSafe for Command

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### impl Freeze for Command

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### impl Send for Command

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### impl Sync for Command

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### impl Unpin for Command

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### impl UnsafeUnpin for Command

## Blanket Implementations§

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### impl<T> Any for T
where T: 'static + ?Sized,

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#### fn type_id(&self) -> TypeId

Gets the `TypeId` of `self`. Read more
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### impl<T> Borrow<T> for T
where T: ?Sized,

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#### fn borrow(&self) -> &T

Immutably borrows from an owned value. Read more
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### impl<T> BorrowMut<T> for T
where T: ?Sized,

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#### fn borrow_mut(&mut self) -> &mut T

Mutably borrows from an owned value. Read more
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### impl<T> From<T> for T

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#### fn from(t: T) -> T

Returns the argument unchanged.

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### impl<T, U> Into<U> for T
where U: From<T>,

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#### fn into(self) -> U

Calls `U::from(self)`.

That is, this conversion is whatever the implementation of `From<T> for U` chooses to do.

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### impl<T, U> TryFrom<U> for T
where U: Into<T>,

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#### type Error = Infallible

The type returned in the event of a conversion error.
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#### fn try_from(value: U) -> Result<T, <T as TryFrom<U>>::Error>

Performs the conversion.
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### impl<T, U> TryInto<U> for T
where U: TryFrom<T>,

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#### type Error = <U as TryFrom<T>>::Error

The type returned in the event of a conversion error.
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#### fn try_into(self) -> Result<U, <U as TryFrom<T>>::Error>

Performs the conversion.

## Layout§

Note: Most layout information is completely unstable and may even differ between compilations. The only exception is types with certain `repr(...)` attributes. Please see the Rust Reference's “Type Layout” chapter for details on type layout guarantees.

Size: 328 bytes