5978 Trailing whitespaces are stripped in raw string literals in doc tests

[IVIURRAY]

Fixes issue: #5978

WIP: Have created the test for this feature just need to implement the code.

[ytmimi]

Thanks for picking this up! based on my up front investigation I suspect this will be tricky one to solve (but I could be wrong). If you're looking for a good first issues to work on I might be able to find a few from the backlog.

[IVIURRAY]

Ok, I'm a little stuck on this one. Wondering if I can get some help. I've read over the documentation provided on the github page and followed the advice on #5978 (comment) but still struggling to understand where to make this change.

rustfmt/src/comment.rs

Lines 376 to 383 in 2174e60

	rewrite_comment_inner(
	first_group,
	block_style,
	style,
	shape,
	config,
	is_doc_comment || style.is_doc_comment(),
	)?

I can see on the above code block I'm getting the following output. Now, I what I don't understand is if I should have the r#"" block as its own Span to be processed or if I should process it as part of this snippet.

/// String literal test
/// ```rust
/// let expected = "\nfoo \n";
/// assert_eq!(expected, r#"
/// foo
/// "#);
/// ```

I'm thinking if I was to process this in its own snippet then I would probably mark some sort of "is inside raw code block" variable and not touch the following lines until I see the "# end.

Would apprechiate some help on this one :)

[IVIURRAY]

@ytmimi - ha you must've been reading my mind. I just commeted for help as you replied.

I did look over the "good first issue" tags but nothing took my fancy or I just didn't understand that is why I opted for a more recent issue. I am looking to get more involved in Rust so any issues you fire my way I will happily try to take a look (maybe with some guidence).

[ytmimi]

@IVIURRAY great to hear that you want to get more involved! The team greatly appreciates the help 🙏🏼! For now, take a look at #5801. If you need help feel free to reach out on Rust’s Zulip in the t-rustfmt stream.