rustfmt cannot format code example with long #-hiding line

[Emilgardis]

I've had an issue with format_code_in_doc_comments for some time and decided to finally try to fix it. The issue was that some of my examples did not get formatted.

While trying to implement a fix I managed to find the cause (#) and a workaround, but I'm not able to go further. A minimal repro here

https://github.com/Emilgardis/rustfmt-no-format/blob/main/src/lib.rs

and the fix being to increase max_width (in this example to 101)

Now, the line that is problematic is

/// # let long: Fooooooooooooooooooooooooooooooooo = Fooooooooooooooooooooooooooooooooo::hi();

however, that's only 94 characters in total starting from the start of the line, not from /// .

My expectation with #-hiding in rust examples is that it should not prevent this, and in fact, removing the # you can make the line as long as you want and the other code (and the long line) gets formatted.

[ytmimi]

Thanks for reaching out!

I think I know what's going on here, but need to investigate a little further. I'll follow up once I've had a chance to dive a little deeper into this.

[ytmimi]

Linking tracking issue for format_code_in_doc_comments #3348