rust-lang / rust-lang/rustfmt

Leading whitespace in a file isn't removed after formatting if code is indented even 1 character

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#6,603 1 comment 0 reactions 0 assignees View on GitHub

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A-whitespace C-bug P-low
Dominant language
Rust
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Forks
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Avg merge
2d 13h
Merged PRs (30d)
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Description

Code:


    use core::cmp::max;

(empty line, then 4 spaces and a use, github does not display this correctly for me)

after first run of rustfmt:

$ echo -e "\n    use core::cmp::max;" | rustfmt

use core::cmp::max;

(notice the blank line before the use)

after the second run:

$ echo -e "\n    use core::cmp::max;" | rustfmt | rustfmt
use core::cmp::max;

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Research direction

Reproduce the issue with the two commands shown in the report, comparing the first and second rustfmt runs. Trace the rustfmt formatting path responsible for leading blank lines and add a regression test for an empty line followed by an indented use statement. Done means the first run produces the same output as the second.

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
Clearly specified
Newbie friendliness
45/100

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