Auto merge of rust-lang#16647 - Young-Flash:fix_replace_filter_map_next_with_find_map, r=Veykril

fix: replace_filter_map_next_with_find_map shouldn't work for dyn trait close rust-lang/rust-analyzer#16596

Author: bors

crates/hir-ty/src/diagnostics/expr.rs

@@ -17,6 +17,7 @@ use tracing::debug;
 use triomphe::Arc;
 use typed_arena::Arena;
 
+use crate::Interner;
 use crate::{
  db::HirDatabase,
  diagnostics::match_check::{
@@ -149,17 +150,18 @@ impl ExprValidator {
  None => return,
  };
 
- if filter_map_next_checker
- .get_or_insert_with(|| {
- FilterMapNextChecker::new(&self.owner.resolver(db.upcast()), db)
- })
- .check(call_id, receiver, &callee)
- .is_some()
- {
+ let checker = filter_map_next_checker.get_or_insert_with(|| {
+ FilterMapNextChecker::new(&self.owner.resolver(db.upcast()), db)
+ });
+
+ if checker.check(call_id, receiver, &callee).is_some() {
  self.diagnostics.push(BodyValidationDiagnostic::ReplaceFilterMapNextWithFindMap {
  method_call_expr: call_id,
  });
  }
+
+ let receiver_ty = self.infer[*receiver].clone();
+ checker.prev_receiver_ty = Some(receiver_ty);
  }
  }
 
@@ -393,6 +395,7 @@ struct FilterMapNextChecker {
  filter_map_function_id: Option<hir_def::FunctionId>,
  next_function_id: Option<hir_def::FunctionId>,
  prev_filter_map_expr_id: Option<ExprId>,
+ prev_receiver_ty: Option<chalk_ir::Ty<Interner>>,
 }
 
 impl FilterMapNextChecker {
@@ -417,7 +420,12 @@ impl FilterMapNextChecker {
  ),
  None => (None, None),
  };
- Self { filter_map_function_id, next_function_id, prev_filter_map_expr_id: None }
+ Self {
+ filter_map_function_id,
+ next_function_id,
+ prev_filter_map_expr_id: None,
+ prev_receiver_ty: None,
+ }
  }
 
  // check for instances of .filter_map(..).next()
@@ -434,7 +442,11 @@ impl FilterMapNextChecker {
 
  if *function_id == self.next_function_id? {
  if let Some(prev_filter_map_expr_id) = self.prev_filter_map_expr_id {
- if *receiver_expr_id == prev_filter_map_expr_id {
+ let is_dyn_trait = self
+ .prev_receiver_ty
+ .as_ref()
+ .map_or(false, |it| it.strip_references().dyn_trait().is_some());
+ if *receiver_expr_id == prev_filter_map_expr_id && !is_dyn_trait {
  return Some(());
  }
  }

crates/ide-diagnostics/src/handlers/replace_filter_map_next_with_find_map.rs

@@ -80,6 +80,21 @@ fn foo() {
  );
  }
 
+ #[test]
+ fn replace_filter_map_next_dont_work_for_not_sized_issues_16596() {
+ check_diagnostics(
+ r#"
+//- minicore: iterators
+fn foo() {
+ let mut j = [0].into_iter();
+ let i: &mut dyn Iterator<Item = i32> = &mut j;
+ let dummy_fn = |v| (v > 0).then_some(v + 1);
+ let _res = i.filter_map(dummy_fn).next();
+}
+"#,
+ );
+ }
+
  #[test]
  fn replace_filter_map_next_with_find_map_no_diagnostic_without_next() {
  check_diagnostics(