Merge #8938

8938: internal: Fix #8931 r=flodiebold a=flodiebold

  - and add some better checking for similar bugs

Co-authored-by: Florian Diebold <[email protected]>

2 files changed, 5 insertions, 4 deletions

diff --git a/crates/hir/src/lib.rs b/crates/hir/src/lib.rs
index 52d72c3c5..800101c91 100644
--- a/crates/hir/src/lib.rs
+++ b/crates/hir/src/lib.rs
@@ -2053,7 +2053,7 @@ impl Type {
         name: Option<&Name>,
         mut callback: impl FnMut(&Ty, AssocItem) -> Option<T>,
     ) -> Option<T> {
-        let canonical = hir_ty::replace_errors_with_variables(self.ty.clone());
+        let canonical = hir_ty::replace_errors_with_variables(&self.ty);
 
         let env = self.env.clone();
         let krate = krate.id;
@@ -2222,7 +2222,7 @@ impl Type {
     }
 
     pub fn could_unify_with(&self, db: &dyn HirDatabase, other: &Type) -> bool {
-        let tys = hir_ty::replace_errors_with_variables((self.ty.clone(), other.ty.clone()));
+        let tys = hir_ty::replace_errors_with_variables(&(self.ty.clone(), other.ty.clone()));
         could_unify(db, self.env.clone(), &tys)
     }
 }
diff --git a/crates/hir/src/semantics.rs b/crates/hir/src/semantics.rs
index 38bd376bc..1b5064b5a 100644
--- a/crates/hir/src/semantics.rs
+++ b/crates/hir/src/semantics.rs
@@ -505,9 +505,10 @@ impl<'db> SemanticsImpl<'db> {
     }
 
     fn resolve_method_call_as_callable(&self, call: &ast::MethodCallExpr) -> Option<Callable> {
-        // FIXME: this erases Substs
+        // FIXME: this erases Substs, we should instead record the correct
+        // substitution during inference and use that
         let func = self.resolve_method_call(call)?;
-        let (ty, _) = self.db.value_ty(func.into()).into_value_and_skipped_binders();
+        let ty = hir_ty::TyBuilder::value_ty(self.db, func.into()).fill_with_unknown().build();
         let resolver = self.analyze(call.syntax()).resolver;
         let ty = Type::new_with_resolver(self.db, &resolver, ty)?;
         let mut res = ty.as_callable(self.db)?;