rustfmt produces invalid syntax for struct with unmatched quote in trailing block comment

[soruh]

Describe the bug

This code:

struct Foo {
    field: u8, /* test " */
}

is turned into this by running cargo fmt

struct Foo {
    field: u8, /* test " */
               }
}

A version without the unmatched quote is formatted correctly:
This code:

struct Foo {
    field: u8, /* test */
}

is not changed

To Reproduce

run rustfmt on the above code.

Expected behavior

rustfmt should not produce the erroneous closing brace

Meta

• rustfmt version:

rustfmt 1.4.36-nightly (7de6968 2021-02-07)
cargo 1.52.0-nightly (c68432f1e 2021-03-02)
rustc 1.52.0-nightly (234781afe 2021-03-07)

• From where did you install rustfmt?:

rustup

• How do you run rustfmt:

- cargo fmt
- rust-analyser in vscode

[memoryruins]

Derived from the original example, struct S /*"*/; led to

thread 'main' panicked at 'bad span: `;`: `struct S /*"*/;`', src\tools\rustfmt\src\source_map.rs:52:13

RUST_BACKTRACE=full returns <unknown> for me currently so isn't very useful.

stack backtrace:
   0:     0x7ff78aac42de - <unknown>
   1:     0x7ff78aadb89c - <unknown>
 ...

nightly-x86_64-pc-windows-msvc (default)
rustc 1.53.0-nightly (07e0e2ec2 2021-03-24)

[calebcartwright]

This is a duplicate of a known issue that's been fixed in source and is pending release. Leaving it open for now as a reminder to myself to add test cases for the provided snippets.

[ChinYing-Li]

Hello @calebcartwright I would like to add the test cases and do the back-porting for this issue if it's not already done by someone else.

[calebcartwright]

Hello @calebcartwright I would like to add the test cases and do the back-porting for this issue if it's not already done by someone else.

Great thanks! IIRC #4320 was the PR that resolved the underlying issue so you may want to start there

[karyon]

As far as I can see this was fixed and can be closed!

[soruh]

I just saw this has a backport pending label, should I reopen it?

[karyon]

#4796 was the backport to 1.x as far as I can tell, so I think this is fine (I'm not the maintainer, though)

[soruh]

Ah, I'll just keep it closed then, thank you!