Double Space between pub and type in newtype when an attribute is followed by a comment

[passcod]

This looks related to #4671 but the attribute is not very long at all.

This formats with two spaces:

pub struct Newtype(
    /// Doc
    #[doc()] //
    pub  Vec<u8>,
);

This formats with one:

pub struct Newtype(
    /// Doc
    #[doc()]
    pub Vec<u8>,
);

Playground: https://play.rust-lang.org/?version=stable&mode=debug&edition=2021&gist=6abf771bd72b8a98d38368badd4916de

[passcod]

In fact #4671 has since regressed: https://play.rust-lang.org/?version=stable&mode=debug&edition=2021&gist=8704d67dbdb46c95638015a55d4fb997

[ytmimi]

@passcod thanks for the report. Some background; #4671 was merged into what's now the rustfmt-2.0.0-rc.2 branch, which was never released. You can run git branch -r --contains a9876e8 to confirm that. The current master branch has diverged significantly from rustfmt-2.0.0-rc.2, and the PR is labeled with backport-triage to indicate that the team needs to review how these changes can be brought back into the main development branch.

That being said, I'm pretty sure this is related / is a duplicate of the issues that #5708 is looking to resolve. I've checked and the linked PR resolves this issue and I've added a test case in that PR.