1 files changed, 15 insertions, 14 deletions

diff --git a/crates/hir_def/src/resolver.rs b/crates/hir_def/src/resolver.rs
index 77ff21739..42736171e 100644
--- a/crates/hir_def/src/resolver.rs
+++ b/crates/hir_def/src/resolver.rs
@@ -19,10 +19,10 @@ use crate::{
     path::{ModPath, PathKind},
     per_ns::PerNs,
     visibility::{RawVisibility, Visibility},
-    AdtId, AssocContainerId, ConstId, ConstParamId, ContainerId, DefWithBodyId, EnumId,
-    EnumVariantId, FunctionId, GenericDefId, GenericParamId, HasModule, ImplId, LifetimeParamId,
-    LocalModuleId, Lookup, ModuleDefId, ModuleId, StaticId, StructId, TraitId, TypeAliasId,
-    TypeParamId, VariantId,
+    AdtId, AssocContainerId, ConstId, ConstParamId, DefWithBodyId, EnumId, EnumVariantId,
+    FunctionId, GenericDefId, GenericParamId, HasModule, ImplId, LifetimeParamId, LocalModuleId,
+    Lookup, ModuleDefId, ModuleId, StaticId, StructId, TraitId, TypeAliasId, TypeParamId,
+    VariantId,
 };
 
 #[derive(Debug, Clone, Default)]
@@ -342,6 +342,16 @@ impl Resolver {
                     traits.extend(prelude_def_map[prelude.local_id].scope.traits());
                 }
                 traits.extend(m.def_map[m.module_id].scope.traits());
+
+                // Add all traits that are in scope because of the containing DefMaps
+                m.def_map.with_ancestor_maps(db, m.module_id, &mut |def_map, module| {
+                    if let Some(prelude) = def_map.prelude() {
+                        let prelude_def_map = prelude.def_map(db);
+                        traits.extend(prelude_def_map[prelude.local_id].scope.traits());
+                    }
+                    traits.extend(def_map[module].scope.traits());
+                    None::<()>
+                });
             }
         }
         traits
@@ -678,19 +688,10 @@ impl HasResolver for DefWithBodyId {
     }
 }
 
-impl HasResolver for ContainerId {
-    fn resolver(self, db: &dyn DefDatabase) -> Resolver {
-        match self {
-            ContainerId::ModuleId(it) => it.resolver(db),
-            ContainerId::DefWithBodyId(it) => it.module(db).resolver(db),
-        }
-    }
-}
-
 impl HasResolver for AssocContainerId {
     fn resolver(self, db: &dyn DefDatabase) -> Resolver {
         match self {
-            AssocContainerId::ContainerId(it) => it.resolver(db),
+            AssocContainerId::ModuleId(it) => it.resolver(db),
             AssocContainerId::TraitId(it) => it.resolver(db),
             AssocContainerId::ImplId(it) => it.resolver(db),
         }