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handle non matching enum pattern types

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This commit is contained in:
Josh Mcguigan
2020-04-05 10:16:34 -07:00
parent b87b7a088f
commit 43dfd89493
2 changed files with 57 additions and 41 deletions
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30
crates/ra_hir_ty/src/expr.rs
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@@ -67,7 +67,7 @@ impl<'a, 'b> ExprValidator<'a, 'b> {
fn validate_match(
&mut self,
id: ExprId,
expr: ExprId,
match_expr: ExprId,
arms: &[MatchArm],
db: &dyn HirDatabase,
infer: Arc<InferenceResult>,
@@ -75,18 +75,32 @@ impl<'a, 'b> ExprValidator<'a, 'b> {
let (body, source_map): (Arc<Body>, Arc<BodySourceMap>) =
db.body_with_source_map(self.func.into());
let match_expr: &hir_def::expr::Expr = &body[expr];
let match_expr_ty = match infer.type_of_expr.get(match_expr) {
Some(ty) => ty,
// If we can't resolve the type of the match expression
// we cannot perform exhaustiveness checks.
None => return,
};
let cx = MatchCheckCtx { body: body.clone(), match_expr, infer, db };
let cx = MatchCheckCtx { body, infer: infer.clone(), db };
let pats = arms.iter().map(|arm| arm.pat);
let mut seen = Matrix::empty();
for pat in pats {
// If we had a NotUsefulMatchArm diagnostic, we could
// check the usefulness of each pattern as we added it
// to the matrix here.
let v = PatStack::from_pattern(pat);
seen.push(&cx, v);
// We skip any patterns whose type we cannot resolve.
if let Some(pat_ty) = infer.type_of_pat.get(pat) {
// We only include patterns whose type matches the type
// of the match expression. If we had a InvalidMatchArmPattern
// diagnostic or similar we could raise that in an else
// block here.
if pat_ty == match_expr_ty {
// If we had a NotUsefulMatchArm diagnostic, we could
// check the usefulness of each pattern as we added it
// to the matrix here.
let v = PatStack::from_pattern(pat);
seen.push(&cx, v);
}
}
}
match is_useful(&cx, &seen, &PatStack::from_wild()) {