Pretty-print parenthesis around binary in postfix match

[scrabsha]

Fixes #124206.

[rustbot]

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[RossSmyth]

Could you please either give the test name something descriptive about what the test tests (idk pfix-match-paren or something) or make a new directory for postfix match within the pretty directory. Adding tests with issue numbers, while common, makes maintenance frustrating.

[scrabsha]

Could you please either give the test name something descriptive about what the test tests (idk pfix-match-paren or something) or make a new directory for postfix match within the pretty directory. Adding tests with issue numbers, while common, makes maintenance frustrating.

I mkdired tests/pretty/postfix-match and moved every postfix-match-related test in it. Thanks for the suggestion!

[scrabsha]

This looks incorrect. Is it an issue in my code or in the pretty printer?

[dtolnay]

This is going to cause double parens to be put around cases like repro!(1 + Struct {}). ((1 + Struct {})).match { _ => {} }

In general print_expr_as_cond is not a correct thing to be using here. That is for syntactic positions where a { is ambiguous between being a part of the matched expression / if condition / while condition, vs being the body for the match/if/while. It isn't applicable to postfix match.

Postfix match needs to be printed like very other expression kind containing ., such as field accesses and method call expressions and postfix await.

[scrabsha]

@dtolnay I modified my changes according to your comment and added your example in the test suite. Thanks!

@rustbot label -S-waiting-on-author +S-waiting-on-review

[dtolnay]

Thanks!

[dtolnay]

@bors r+

[bors]

📌 Commit c8ff8a4 has been approved by dtolnay

It is now in the queue for this repository.