Include label in the span of loops

[marcusklaas]

This closes #27042.

I'd love to know if there's a way to make a regression test for this!

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[ftxqxd]

If you put the label on a separate line from the loop’s body, you can test that an arbitrary error’s span starts on the line of the label:

fn main() {
    let _: i32 =
        'a: //~ ERROR mismatched types
        loop { break };
    let _: i32 =
        'b: //~ ERROR mismatched types
        while true { break };
    let _: i32 =
        'c: //~ ERROR mismatched types
        for _ in None { break };
}

(I haven’t actually tested this, but it should work.)

[marcusklaas]

Thanks @P1start, that worked beautifully. The test even helped me catch a case I forgot about (while let).

[nrc]

Could you say what is actually being tested here (the issue number is clear from the file name).

[nrc]

r=me modulo the test comment nit

[marcusklaas]

Updated!

[nrc]

@bors r+

[bors]

📌 Commit 1296360 has been approved by nrc

[bors]

⌛ Testing commit 1296360 with merge be23d44...

[bors]

☀️ Test successful - auto-linux-32-nopt-t, auto-linux-32-opt, auto-linux-64-nopt-t, auto-linux-64-opt, auto-linux-64-x-android-t, auto-mac-32-opt, auto-mac-64-nopt-t, auto-mac-64-opt, auto-win-gnu-32-nopt-t, auto-win-gnu-32-opt, auto-win-gnu-64-nopt-t, auto-win-gnu-64-opt