bjoernager/rust
bjoernager/rust
1
Fork 0
Code Activity

Don't suggest adding let in certain if conditions

Browse source
This commit is contained in:
Michael Goulet 2022-06-07 20:53:02 -07:00
parent b17e9d76f2
commit 2ae1ec9119
6 changed files with 142 additions and 8 deletions
Download patch file Download diff file Expand all files Collapse all files

22
compiler/rustc_resolve/src/late/diagnostics.rs
View file

@ -265,13 +265,21 @@ impl<'a: 'ast, 'ast> LateResolutionVisitor<'a, '_, 'ast> {
);
}
match (source, self.diagnostic_metadata.in_if_condition) {
(PathSource::Expr(_), Some(Expr { span, kind: ExprKind::Assign(..), .. })) => {
err.span_suggestion_verbose(
span.shrink_to_lo(),
"you might have meant to use pattern matching",
"let ".to_string(),
Applicability::MaybeIncorrect,
);
(
PathSource::Expr(_),
Some(Expr { span: expr_span, kind: ExprKind::Assign(lhs, _, _), .. }),
) => {
// Icky heuristic so we don't suggest:
// `if (i + 2) = 2` => `if let (i + 2) = 2` (approximately pattern)
// `if 2 = i` => `if let 2 = i` (lhs needs to contain error span)
if lhs.is_approximately_pattern() && lhs.span.contains(span) {
err.span_suggestion_verbose(
expr_span.shrink_to_lo(),
"you might have meant to use pattern matching",
"let ".to_string(),
Applicability::MaybeIncorrect,
);
}
}
_ => {}
}