bendns' repos / rust-analyzer
Unnamed repository; edit this file 'description' to name the repository.
Diffstat (limited to 'crates/hir-ty/src/diagnostics/expr.rs')
-rw-r--r--crates/hir-ty/src/diagnostics/expr.rs55
1 files changed, 45 insertions, 10 deletions
diff --git a/crates/hir-ty/src/diagnostics/expr.rs b/crates/hir-ty/src/diagnostics/expr.rs
index be4de11ceb..d04419c5e5 100644
--- a/crates/hir-ty/src/diagnostics/expr.rs
+++ b/crates/hir-ty/src/diagnostics/expr.rs
@@ -333,17 +333,20 @@ impl<'db> ExprValidator<'db> {
let pattern_arena = Arena::new();
let cx = MatchCheckCtx::new(self.owner.module(self.db()), &self.infcx, self.env);
for stmt in &**statements {
- let diag = match *stmt {
+ match *stmt {
Statement::Expr { expr: stmt_expr, has_semi: true } if self.validate_lints => {
- self.check_unused_must_use(stmt_expr)
+ let mut diags = Vec::new();
+ self.check_unused_must_use(stmt_expr, &mut diags);
+ self.diagnostics.extend(diags);
}
Statement::Let { pat, initializer, else_branch: None, .. } => {
- self.check_non_exhaustive_let(&cx, &pattern_arena, pat, initializer)
+ if let Some(diag) =
+ self.check_non_exhaustive_let(&cx, &pattern_arena, pat, initializer)
+ {
+ self.diagnostics.push(diag);
+ }
}
- _ => None,
- };
- if let Some(diag) = diag {
- self.diagnostics.push(diag);
+ _ => {}
}
}
}
@@ -415,7 +418,37 @@ impl<'db> ExprValidator<'db> {
pattern
}
- fn check_unused_must_use(&self, expr: ExprId) -> Option<BodyValidationDiagnostic<'db>> {
+ fn check_unused_must_use(
+ &self,
+ mut expr: ExprId,
+ acc: &mut Vec<BodyValidationDiagnostic<'db>>,
+ ) {
+ // Walk through container expressions so that the value-producing leaf is
+ // checked even when wrapped in a block, `unsafe { .. }`, `if`/`match`, or
+ // a `const { .. }` block. Single-tail chains are followed by reassigning
+ // `expr`; branching containers (`if`/`match`) recurse on each arm.
+ loop {
+ match &self.body[expr] {
+ Expr::Block { tail: Some(tail), .. }
+ | Expr::Unsafe { tail: Some(tail), .. }
+ | Expr::Const(tail) => expr = *tail,
+ Expr::If { then_branch, else_branch, .. } => {
+ self.check_unused_must_use(*then_branch, acc);
+ if let Some(else_branch) = else_branch {
+ self.check_unused_must_use(*else_branch, acc);
+ }
+ return;
+ }
+ Expr::Match { arms, .. } => {
+ for arm in arms.iter() {
+ self.check_unused_must_use(arm.expr, acc);
+ }
+ return;
+ }
+ _ => break,
+ }
+ }
+
let fn_def = match &self.body[expr] {
Expr::Call { callee, .. } => {
let callee_ty = self.infer.expr_ty(*callee);
@@ -430,7 +463,7 @@ impl<'db> ExprValidator<'db> {
Expr::MethodCall { .. } => {
self.infer.method_resolution(expr).map(|(func, _)| func.into())
}
- _ => return None,
+ _ => None,
};
let ty_def = self.infer.type_of_expr_with_adjust(expr).and_then(|ty| match ty.kind() {
TyKind::Adt(adt, _) => Some(adt.def_id().into()),
@@ -440,7 +473,9 @@ impl<'db> ExprValidator<'db> {
AttrFlags::must_use_message(self.db(), owner?)
.map(|message| BodyValidationDiagnostic::UnusedMustUse { expr, message })
};
- must_use_diag(fn_def).or_else(|| must_use_diag(ty_def))
+ if let Some(diag) = must_use_diag(fn_def).or_else(|| must_use_diag(ty_def)) {
+ acc.push(diag);
+ }
}
fn check_for_trailing_return(&mut self, body_expr: ExprId, body: &Body) {