rust-lang / rust-lang/rustfmt

Poor formatting of macro_rules rhs with consecutive top-level blocks

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#2,740 3 comments 0 reactions 0 assignees View on GitHub

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A-macros I-poor-formatting P-low
Dominant language
Rust
Stars
7k
Forks
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Avg merge
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Merged PRs (30d)
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Description

Rustfmt turns this input:

macro_rules! repro {
    () => {
        {
            let _guard = ();
        }
        {
            let _guard = ();
        }
    };
}

into this output:

macro_rules! repro {
    () => {{
        let _guard = ();
    }
    {
        let _guard = ();
    }};
}

I believe the original is clearer.

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First steps

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  3. Fork the repository and make your change on a branch.
  4. Open a pull request that references the issue number.

Research direction

Reproduce the macro_rules! example with rustfmt and inspect the formatting path for macro right-hand-side blocks. Done when consecutive top-level blocks retain the clearer structure shown in the issue and a regression check covers the example.

Written by the indexing model from the issue text.

Assessment

Tech stack
rust
Domain
tooling
Issue type
Bug
Difficulty
3/5
Estimated time
1-2 days
Activity status
Stale
Clarity
Mostly clear
Newbie friendliness
35/100

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