fix: Make auto-fix note work with clippy

[Muscraft]

Someone pointed out that the suggestion to run cargo --fix did not work properly for cargo clippy. This makes sure the correct command to run is output when running under cargo clippy.

This is done by checking if the RUSTC_WORKSPACE_WRAPPER environment variable is set, since clippy sets this every run. Since other things can use RUSTC_WORKSPACE_WRAPPER, we look for a wrapper named clippy-driver.

Since clippy might not be available everywhere cargo is tested, this is tested using a rustc wrapper.

[rustbot]

r? @ehuss

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[ehuss]

Unfortunately clippy isn't the only tool which sets RUSTC_WORKSPACE_WRAPPER. I think some other approach will be needed here.

[Muscraft]

I was worried about that, I was hoping it would be fine since it was used before. The only thing I can think of is using CLIPPY_ARGS, which appears to pass the test I wrote. I will update it to that.

[Muscraft]

After some discussion, it was decided that RUSTC_WORKSPACE_WRAPPER would be better as it is already agreed upon by clippy and cargo. Since other things can use RUSTC_WORKSPACE_WRAPPER, we look for a wrapper named clippy-driver.

[Rustin170506]

Looks goog to me. Thanks!

[weihanglo]

Looks good! Just some tiny not important stuff.

[weihanglo]

(nit)

Suggested change

	let command = match rustc_workspace_wrapper {
	#[cfg(windows)]
	Some(wrapper) if wrapper.ends_with("clippy-driver.exe") => {
	"cargo clippy --fix"
	}
	#[cfg(not(windows))]
	Some(wrapper) if wrapper.ends_with("clippy-driver") => "cargo clippy --fix",
	_ => "cargo fix",
	};
	let clippy = std::ffi::OsStr::new("clippy-driver");
	let command = match rustc_workspace_wrapper.as_ref().and_then(|x| x.file_stem())
	{
	Some(wrapper) if wrapper == clippy => "cargo clippy --fix",
	_ => "cargo fix",
	};

[weihanglo]

(nit)

Suggested change

	" (run `{} --{}` to apply {})",
	command, args, suggestions
	" (run `{command} --{args}` to apply {suggestions})"

[weihanglo]

Thanks!

@bors r+

[bors]

📌 Commit 33c3208 has been approved by weihanglo

It is now in the queue for this repository.

[bors]

⌛ Testing commit 33c3208 with merge 8607003...

[bors]

☀️ Test successful - checks-actions
Approved by: weihanglo
Pushing 8607003 to master...