Show five traits implementation in help when there are exactly five

[seppo0010]

Fixes#39802

[rust-highfive]

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[eddyb]

r? @jonathandturner

[gralpli]

Are those two backticks at the end of the line intentional?

All other tests within ui/did_you_mean/ use a separate .stderr file. I think it's not possible to use this inline error notation here.

[seppo0010]

You are right, I copied it from src/test/ui/did_you_mean/issue-21659-show-relevant-trait-impls-1.rs which has both but I did not noticed the stderr file.

[gralpli]

Maybe you could add two more test cases (within this same file): one if there are just four implementations found and one if there are six (so that it says 'and 2 others').

[ranma42]

This looks like a complex way to compute cmp::min(5, impl_candidates.len())
EDIT: yet it is not, if impl_candidates.len() is greater than 5, this computation returns 4

[ranma42]

How about

let end = if impl_candidates.len() <= 5{
impl_candidates.len()}else{4};

? At least for me, it would make it easier to immediately grasp the behaviour.

[seppo0010]

Good idea. I've added it and squashed the commits.

[sophiajt]

Looks good. Thanks for the PR!

@bors r+

[bors]

📌 Commit ca54fc7 has been approved by jonathandturner