Don't typecheck suggested method call

Only make the use-dot-operator-to-call-method suggestion, but do not
double down and use the recovered type to perform method call
typechecking as it will produce confusing diagnostics on the "fixed"
code.

compiler/rustc_hir_typeck/src/callee.rs

@@ -420,20 +420,14 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
  .steal_diagnostic(segment.ident.span, StashKey::CallIntoMethod)
  {
  // Try suggesting `foo(a)` -> `a.foo()` if possible.
- if let Some(ty) =
- self.suggest_call_as_method(
- &mut diag,
- segment,
- arg_exprs,
- call_expr,
- expected
- )
- {
- diag.emit();
- return ty;
- } else {
- diag.emit();
- }
+ self.suggest_call_as_method(
+ &mut diag,
+ segment,
+ arg_exprs,
+ call_expr,
+ expected
+ );
+ diag.emit();
  }
 
  let err = self.report_invalid_callee(call_expr, callee_expr, callee_ty, arg_exprs);
@@ -496,9 +490,11 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
  arg_exprs: &'tcx [hir::Expr<'tcx>],
  call_expr: &'tcx hir::Expr<'tcx>,
  expected: Expectation<'tcx>,
- ) -> Option<Ty<'tcx>> {
+ ) {
  if let [callee_expr, rest @ ..] = arg_exprs {
- let callee_ty = self.typeck_results.borrow().expr_ty_adjusted_opt(callee_expr)?;
+ let Some(callee_ty) = self.typeck_results.borrow().expr_ty_adjusted_opt(callee_expr) else {
+ return;
+ };
 
  // First, do a probe with `IsSuggestion(true)` to avoid emitting
  // any strange errors. If it's successful, then we'll do a true
@@ -513,7 +509,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
  ProbeScope::AllTraits,
  expected.only_has_type(self),
  ) else {
- return None;
+ return;
  };
 
  let pick = self.confirm_method(
@@ -525,7 +521,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
  segment,
  );
  if pick.illegal_sized_bound.is_some() {
- return None;
+ return;
  }
 
  let up_to_rcvr_span = segment.ident.span.until(callee_expr.span);
@@ -567,22 +563,8 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
  sugg,
  Applicability::MaybeIncorrect,
  );
-
- // Let's check the method fully now
- let return_ty = self.check_method_argument_types(
- segment.ident.span,
- call_expr,
- Ok(pick.callee),
- rest,
- TupleArgumentsFlag::DontTupleArguments,
- expected,
- );
-
- return Some(return_ty);
  }
  }
-
- None
  }
 
  fn report_invalid_callee(

tests/ui/typeck/issue-106929.rs

@@ -0,0 +1,13 @@
+struct Client;
+
+impl Client {
+ fn post<T: std::ops::Add>(&self, _: T, _: T) {}
+}
+
+fn f() {
+ let c = Client;
+ post(c, ());
+ //~^ ERROR cannot find function `post` in this scope
+}
+
+fn main() {}

tests/ui/typeck/issue-106929.stderr

@@ -0,0 +1,15 @@
+error[E0425]: cannot find function `post` in this scope
+ --> $DIR/issue-106929.rs:9:5
+ |
+LL | post(c, ());
+ | ^^^^ not found in this scope
+ |
+help: use the `.` operator to call the method `post` on `&Client`
+ |
+LL - post(c, ());
+LL + c.post(());
+ |
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0425`.