x fmt tries to format non-rust files

[Noratrieb]

formatting modified file compiler/rustc_error_messages/locales/en-US/borrowck.ftl
error: unknown start of token: `
 --> /home/nilsh/projects/rust/compiler/rustc_error_messages/locales/en-US/borrowck.ftl:2:33
  |
2 |     cannot move a value of type `{$ty}`
  |                                 ^
  |
help: Unicode character '`' (Grave Accent) looks like ''' (Single Quote), but it is not
  |
2 |     cannot move a value of type '{$ty}`
  |                                 ~

error: unknown start of token: `

When there was a change in a .ftl or other non-rust file, bootstrap tries to format it, which makes rustfmt very sad.

cc @albertlarsan68 and @jyn514 who broke this in #105702

[jyn514]

I think we just need to filter .rs files before passing them to rustfmt.

[Noratrieb]

This will probably be hit a lot by contributors so I'll pin it for better visibility.

[chenyukang]

@rustbot claim

[albertlarsan68]

Normally, the walker already filters for .rs files, per https://docs.rs/ignore/latest/ignore/struct.WalkBuilder.html. Maybe the ignore crate docs are not fully up to date, or I didn't understand them correctly.

[albertlarsan68]

The workaround is to run x fmt . (notice the dot at the end of the command).

[chenyukang]

I think if we add it like this:

ignore_fmt.add(&format!("!/{}", untracked_path)).expect(&untracked_path);

ignore will always not ignore it anymore.

[albertlarsan68]

Maybe try to put the part I added before the ignore part, maybe this makes the ignore list work again?

The thing that intrigues me the most is the fact that the .stderr files are not ignored later by the file type filter.

[chenyukang]

For any Rust files we changed locally, our current solution will try to format it, in some scenarios we may not want to format it, such as some files in UI?

[chenyukang]

Maybe try to put the part I added before the ignore part, maybe this makes the ignore list work again?

The thing that intrigues me the most is the face that the .stderr files are not ignored later by the file type filter.

Seems right, my current fix is not completed.

[jyn514]

Normally, the walker already filters for .rs files, per https://docs.rs/ignore/latest/ignore/struct.WalkBuilder.html. Maybe the ignore crate docs are not fully up to date, or I didn't understand them correctly.

I think since you explicitly add the files to ignore_fmt, that overrides the types filter.

[chenyukang]

from my local experiment, seems rustfmt.toml is still expected, I changed some files which ignored in rustfmt.toml, they are actually not sent to formatter:

cat@LAPTOP-V6U0QKD4:~/code/rust$ x fmt
Building rustbuild
   Compiling bootstrap v0.0.0 (/home/cat/code/rust/src/bootstrap)
    Finished dev [unoptimized] target(s) in 5.25s
formatting modified file library/portable-simd/crates/core_simd/src/vendor/arm.rs
formatting modified file src/bootstrap/format.rs
formatting modified file src/tools/miri/src/bin/miri.rs
really try to format: DirEntry { dent: Raw(DirEntryRaw { path: "/home/cat/code/rust/src/bootstrap/format.rs", follow_link: false, depth: 3 }), err: None }
Build completed successfully in 0:00:07

[apiraino]

WG-prioritization assigning priority (Zulip discussion).

@rustbot label -I-prioritize +P-high