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.rs74
1 files changed, 64 insertions, 10 deletions
diff --git a/crates/hir-ty/src/diagnostics/expr.rs b/crates/hir-ty/src/diagnostics/expr.rs
index e52fae06d7..6e5a7cce9c 100644
--- a/crates/hir-ty/src/diagnostics/expr.rs
+++ b/crates/hir-ty/src/diagnostics/expr.rs
@@ -4,20 +4,25 @@
use std::fmt;
+use chalk_solve::rust_ir::AdtKind;
use either::Either;
-use hir_def::lang_item::LangItem;
-use hir_def::{resolver::HasResolver, AdtId, AssocItemId, DefWithBodyId, HasModule};
-use hir_def::{ItemContainerId, Lookup};
+use hir_def::{
+ lang_item::LangItem,
+ resolver::{HasResolver, ValueNs},
+ AdtId, AssocItemId, DefWithBodyId, HasModule, ItemContainerId, Lookup,
+};
use intern::sym;
use itertools::Itertools;
use rustc_hash::FxHashSet;
use rustc_pattern_analysis::constructor::Constructor;
-use syntax::{ast, AstNode};
+use syntax::{
+ ast::{self, UnaryOp},
+ AstNode,
+};
use tracing::debug;
use triomphe::Arc;
use typed_arena::Arena;
-use crate::Interner;
use crate::{
db::HirDatabase,
diagnostics::match_check::{
@@ -25,7 +30,7 @@ use crate::{
pat_analysis::{self, DeconstructedPat, MatchCheckCtx, WitnessPat},
},
display::HirDisplay,
- InferenceResult, Ty, TyExt,
+ Adjust, InferenceResult, Interner, Ty, TyExt, TyKind,
};
pub(crate) use hir_def::{
@@ -117,7 +122,7 @@ impl ExprValidator {
Expr::If { .. } => {
self.check_for_unnecessary_else(id, expr, db);
}
- Expr::Block { .. } => {
+ Expr::Block { .. } | Expr::Async { .. } | Expr::Unsafe { .. } => {
self.validate_block(db, expr);
}
_ => {}
@@ -236,7 +241,12 @@ impl ExprValidator {
return;
}
- let report = match cx.compute_match_usefulness(m_arms.as_slice(), scrut_ty.clone()) {
+ let known_valid_scrutinee = Some(self.is_known_valid_scrutinee(scrutinee_expr, db));
+ let report = match cx.compute_match_usefulness(
+ m_arms.as_slice(),
+ scrut_ty.clone(),
+ known_valid_scrutinee,
+ ) {
Ok(report) => report,
Err(()) => return,
};
@@ -253,8 +263,52 @@ impl ExprValidator {
}
}
+ // [rustc's `is_known_valid_scrutinee`](https://github.com/rust-lang/rust/blob/c9bd03cb724e13cca96ad320733046cbdb16fbbe/compiler/rustc_mir_build/src/thir/pattern/check_match.rs#L288)
+ //
+ // While the above function in rustc uses thir exprs, r-a doesn't have them.
+ // So, the logic here is getting same result as "hir lowering + match with lowered thir"
+ // with "hir only"
+ fn is_known_valid_scrutinee(&self, scrutinee_expr: ExprId, db: &dyn HirDatabase) -> bool {
+ if self
+ .infer
+ .expr_adjustments
+ .get(&scrutinee_expr)
+ .is_some_and(|adjusts| adjusts.iter().any(|a| matches!(a.kind, Adjust::Deref(..))))
+ {
+ return false;
+ }
+
+ match &self.body[scrutinee_expr] {
+ Expr::UnaryOp { op: UnaryOp::Deref, .. } => false,
+ Expr::Path(path) => {
+ let value_or_partial = self
+ .owner
+ .resolver(db.upcast())
+ .resolve_path_in_value_ns_fully(db.upcast(), path);
+ value_or_partial.map_or(true, |v| !matches!(v, ValueNs::StaticId(_)))
+ }
+ Expr::Field { expr, .. } => match self.infer.type_of_expr[*expr].kind(Interner) {
+ TyKind::Adt(adt, ..)
+ if db.adt_datum(self.owner.krate(db.upcast()), *adt).kind == AdtKind::Union =>
+ {
+ false
+ }
+ _ => self.is_known_valid_scrutinee(*expr, db),
+ },
+ Expr::Index { base, .. } => self.is_known_valid_scrutinee(*base, db),
+ Expr::Cast { expr, .. } => self.is_known_valid_scrutinee(*expr, db),
+ Expr::Missing => false,
+ _ => true,
+ }
+ }
+
fn validate_block(&mut self, db: &dyn HirDatabase, expr: &Expr) {
- let Expr::Block { statements, .. } = expr else { return };
+ let (Expr::Block { statements, .. }
+ | Expr::Async { statements, .. }
+ | Expr::Unsafe { statements, .. }) = expr
+ else {
+ return;
+ };
let pattern_arena = Arena::new();
let cx = MatchCheckCtx::new(self.owner.module(db.upcast()), self.owner, db);
for stmt in &**statements {
@@ -280,7 +334,7 @@ impl ExprValidator {
has_guard: false,
arm_data: (),
};
- let report = match cx.compute_match_usefulness(&[match_arm], ty.clone()) {
+ let report = match cx.compute_match_usefulness(&[match_arm], ty.clone(), None) {
Ok(v) => v,
Err(e) => {
debug!(?e, "match usefulness error");