4 files changed, 35 insertions, 12 deletions

diff --git a/crates/hir/src/attrs.rs b/crates/hir/src/attrs.rs
index 99fb65bac..9e6a3e155 100644
--- a/crates/hir/src/attrs.rs
+++ b/crates/hir/src/attrs.rs
@@ -2,6 +2,7 @@
 use hir_def::{
     attr::{Attrs, Documentation},
     path::ModPath,
+    per_ns::PerNs,
     resolver::HasResolver,
     AttrDefId, GenericParamId, ModuleDefId,
 };
@@ -112,6 +113,11 @@ fn resolve_doc_path(
     let path = ast::Path::parse(link).ok()?;
     let modpath = ModPath::from_src(path, &Hygiene::new_unhygienic()).unwrap();
     let resolved = resolver.resolve_module_path_in_items(db.upcast(), &modpath);
+    if resolved == PerNs::none() {
+        if let Some(trait_id) = resolver.resolve_module_path_in_trait_items(db.upcast(), &modpath) {
+            return Some(ModuleDefId::TraitId(trait_id));
+        };
+    }
     let def = match ns {
         Some(Namespace::Types) => resolved.take_types()?,
         Some(Namespace::Values) => resolved.take_values()?,
diff --git a/crates/hir/src/code_model.rs b/crates/hir/src/code_model.rs
index 6cbf5cecf..aaa7013b6 100644
--- a/crates/hir/src/code_model.rs
+++ b/crates/hir/src/code_model.rs
@@ -90,7 +90,7 @@ impl Crate {
     }
 
     pub fn root_module(self, db: &dyn HirDatabase) -> Module {
-        let module_id = db.crate_def_map(self.id).root;
+        let module_id = db.crate_def_map(self.id).root();
         Module::new(self, module_id)
     }
 
@@ -302,7 +302,7 @@ impl Module {
     /// in the module tree of any target in `Cargo.toml`.
     pub fn crate_root(self, db: &dyn HirDatabase) -> Module {
         let def_map = db.crate_def_map(self.id.krate);
-        self.with_module_id(def_map.root)
+        self.with_module_id(def_map.root())
     }
 
     /// Iterates over all child modules.
@@ -1000,7 +1000,7 @@ impl MacroDef {
     /// early, in `hir_expand`, where modules simply do not exist yet.
     pub fn module(self, db: &dyn HirDatabase) -> Option<Module> {
         let krate = self.id.krate;
-        let module_id = db.crate_def_map(krate).root;
+        let module_id = db.crate_def_map(krate).root();
         Some(Module::new(Crate { id: krate }, module_id))
     }
 
@@ -1051,6 +1051,16 @@ impl AsAssocItem for TypeAlias {
         as_assoc_item(db, AssocItem::TypeAlias, self.id)
     }
 }
+impl AsAssocItem for ModuleDef {
+    fn as_assoc_item(self, db: &dyn HirDatabase) -> Option<AssocItem> {
+        match self {
+            ModuleDef::Function(it) => it.as_assoc_item(db),
+            ModuleDef::Const(it) => it.as_assoc_item(db),
+            ModuleDef::TypeAlias(it) => it.as_assoc_item(db),
+            _ => None,
+        }
+    }
+}
 fn as_assoc_item<ID, DEF, CTOR, AST>(db: &dyn HirDatabase, ctor: CTOR, id: ID) -> Option<AssocItem>
 where
     ID: Lookup<Data = AssocItemLoc<AST>>,
@@ -1091,6 +1101,13 @@ impl AssocItem {
             AssocContainerId::ContainerId(_) => panic!("invalid AssocItem"),
         }
     }
+
+    pub fn containing_trait(self, db: &dyn HirDatabase) -> Option<Trait> {
+        match self.container(db) {
+            AssocItemContainer::Trait(t) => Some(t),
+            _ => None,
+        }
+    }
 }
 
 impl HasVisibility for AssocItem {
@@ -2029,7 +2046,7 @@ impl Callable {
 pub enum ScopeDef {
     ModuleDef(ModuleDef),
     MacroDef(MacroDef),
-    GenericParam(TypeParam),
+    GenericParam(GenericParam),
     ImplSelfType(Impl),
     AdtSelfType(Adt),
     Local(Local),
diff --git a/crates/hir/src/db.rs b/crates/hir/src/db.rs
index d5d4cf5b6..d444f4bbb 100644
--- a/crates/hir/src/db.rs
+++ b/crates/hir/src/db.rs
@@ -1,13 +1,13 @@
 //! FIXME: write short doc here
 
 pub use hir_def::db::{
-    AttrsQuery, BodyQuery, BodyWithSourceMapQuery, ConstDataQuery, CrateDefMapQueryQuery,
-    CrateLangItemsQuery, DefDatabase, DefDatabaseStorage, EnumDataQuery, ExprScopesQuery,
-    FunctionDataQuery, GenericParamsQuery, ImplDataQuery, ImportMapQuery, InternConstQuery,
-    InternDatabase, InternDatabaseStorage, InternEnumQuery, InternFunctionQuery, InternImplQuery,
-    InternStaticQuery, InternStructQuery, InternTraitQuery, InternTypeAliasQuery, InternUnionQuery,
-    ItemTreeQuery, LangItemQuery, StaticDataQuery, StructDataQuery, TraitDataQuery,
-    TypeAliasDataQuery, UnionDataQuery,
+    AttrsQuery, BlockDefMapQuery, BodyQuery, BodyWithSourceMapQuery, ConstDataQuery,
+    CrateDefMapQueryQuery, CrateLangItemsQuery, DefDatabase, DefDatabaseStorage, EnumDataQuery,
+    ExprScopesQuery, FunctionDataQuery, GenericParamsQuery, ImplDataQuery, ImportMapQuery,
+    InternConstQuery, InternDatabase, InternDatabaseStorage, InternEnumQuery, InternFunctionQuery,
+    InternImplQuery, InternStaticQuery, InternStructQuery, InternTraitQuery, InternTypeAliasQuery,
+    InternUnionQuery, ItemTreeQuery, LangItemQuery, StaticDataQuery, StructDataQuery,
+    TraitDataQuery, TypeAliasDataQuery, UnionDataQuery,
 };
 pub use hir_expand::db::{
     AstDatabase, AstDatabaseStorage, AstIdMapQuery, HygieneFrameQuery, InternEagerExpansionQuery,
diff --git a/crates/hir/src/semantics.rs b/crates/hir/src/semantics.rs
index ab213e04c..0a30b4f5b 100644
--- a/crates/hir/src/semantics.rs
+++ b/crates/hir/src/semantics.rs
@@ -814,7 +814,7 @@ impl<'a> SemanticsScope<'a> {
                 }
                 resolver::ScopeDef::ImplSelfType(it) => ScopeDef::ImplSelfType(it.into()),
                 resolver::ScopeDef::AdtSelfType(it) => ScopeDef::AdtSelfType(it.into()),
-                resolver::ScopeDef::GenericParam(id) => ScopeDef::GenericParam(TypeParam { id }),
+                resolver::ScopeDef::GenericParam(id) => ScopeDef::GenericParam(id.into()),
                 resolver::ScopeDef::Local(pat_id) => {
                     let parent = resolver.body_owner().unwrap().into();
                     ScopeDef::Local(Local { parent, pat_id })