rustfmt breaks a /* ... */ comment into /* ... //, with no terminating */ #6339
Description
With version = "Two" and wrap_comments = true, rustfmt can break a /* ... */ comment by changing one of its lines to start with //. The error does not occur without version "Two" or without wrap_comments. Maybe worth noting, we have both of those options on at work.
(Sorry if this is a duplicate bug, couldn't find anything by searching for is:issue state:open "wrap_comments = true" "version = \"Two\"")
Reproduction steps:
cargo new test-crate
cd test-crate
echo 'version = "Two"
wrap_comments = true' > rustfmt.toml
echo 'use rustc_middle::ty::{self, Region, Ty, TyCtxt}; /* xx xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
* xxxxxxxxxxxxx */
fn main() {}
' > src/main.rs
cargo +nightly fmt # or rustfmt +nightly src/main.rs
cat src/main.rs On my computer, I get:
use rustc_middle::ty::{self, Region, Ty, TyCtxt}; /* xx xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
// xxxxxxxxxxxxx
fn main() {}Which is not valid syntax.
rustfmt version:
$ rustfmt +nightly --version
rustfmt 1.7.1-nightly (506f22b 2024-09-19)Metadata
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ytmimi commentedon Sep 21, 2024
Confirming I can reproduce this using rustfmt 1.8.0-nightly (6157568 2024-09-20),
style_edition=20241 andwrap_comments=true. There have been similar issues reported before and I'll try to dig through the backlog later to find any that seem relevant here.Input
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Footnotes
style_editionreplacesversionin newer rustfmt releases ↩hlopko commentedon Sep 26, 2024
Thanks @ytmimi!
dqkqd commentedon Oct 5, 2024
Is it ok for me to work on this issue? @ytmimi
I think the bug occurred because we try to
rewrite_commentonother_lines, which is a part of a multi lineblock comment.rustfmt/src/missed_spans.rs
Lines 285 to 289 in 5f48fe9
I suppose a correct fix would be not separating comment lines in case of multi line
block comment.However, it will wrap comment in this case below as well.
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ytmimi commentedon Oct 6, 2024
@dqkqd if you're interested in taking a look at this that would be great!
Wrap multi lined trailing block comments (rust-lang#6339)
Wrap multi lined trailing block comments (rust-lang#6339)