3 files changed, 226 insertions, 83 deletions

diff --git a/crates/ra_hir/src/code_model.rs b/crates/ra_hir/src/code_model.rs
index e86077dd6..1b3525011 100644
--- a/crates/ra_hir/src/code_model.rs
+++ b/crates/ra_hir/src/code_model.rs
@@ -31,7 +31,7 @@ use hir_ty::{
     ApplicationTy, Canonical, GenericPredicate, InEnvironment, Substs, TraitEnvironment, Ty,
     TyDefId, TypeCtor,
 };
-use ra_db::{CrateId, CrateName, Edition, FileId};
+use ra_db::{CrateId, Edition, FileId};
 use ra_prof::profile;
 use ra_syntax::ast::{self, AttrsOwner, NameOwner};
 use rustc_hash::FxHashSet;
@@ -94,8 +94,8 @@ impl Crate {
         db.crate_graph()[self.id].edition
     }
 
-    pub fn display_name(self, db: &dyn HirDatabase) -> Option<CrateName> {
-        db.crate_graph()[self.id].display_name.as_ref().cloned()
+    pub fn display_name(self, db: &dyn HirDatabase) -> Option<String> {
+        db.crate_graph()[self.id].display_name.clone()
     }
 
     pub fn query_external_importables(
@@ -1053,12 +1053,14 @@ pub struct ImplDef {
 
 impl ImplDef {
     pub fn all_in_crate(db: &dyn HirDatabase, krate: Crate) -> Vec<ImplDef> {
-        let impls = db.impls_in_crate(krate.id);
-        impls.all_impls().map(Self::from).collect()
+        let inherent = db.inherent_impls_in_crate(krate.id);
+        let trait_ = db.trait_impls_in_crate(krate.id);
+
+        inherent.all_impls().chain(trait_.all_impls()).map(Self::from).collect()
     }
     pub fn for_trait(db: &dyn HirDatabase, krate: Crate, trait_: Trait) -> Vec<ImplDef> {
-        let impls = db.impls_in_crate(krate.id);
-        impls.lookup_impl_defs_for_trait(trait_.id).map(Self::from).collect()
+        let impls = db.trait_impls_in_crate(krate.id);
+        impls.for_trait(trait_.id).map(Self::from).collect()
     }
 
     pub fn target_trait(self, db: &dyn HirDatabase) -> Option<TypeRef> {
@@ -1187,7 +1189,7 @@ impl Type {
             None => return false,
         };
 
-        let canonical_ty = Canonical { value: self.ty.value.clone(), num_vars: 0 };
+        let canonical_ty = Canonical { value: self.ty.value.clone(), kinds: Arc::new([]) };
         method_resolution::implements_trait(
             &canonical_ty,
             db,
@@ -1211,7 +1213,7 @@ impl Type {
                 self.ty.environment.clone(),
                 hir_ty::Obligation::Trait(trait_ref),
             ),
-            num_vars: 0,
+            kinds: Arc::new([]),
         };
 
         db.trait_solve(self.krate, goal).is_some()
@@ -1286,7 +1288,7 @@ impl Type {
     pub fn autoderef<'a>(&'a self, db: &'a dyn HirDatabase) -> impl Iterator<Item = Type> + 'a {
         // There should be no inference vars in types passed here
         // FIXME check that?
-        let canonical = Canonical { value: self.ty.value.clone(), num_vars: 0 };
+        let canonical = Canonical { value: self.ty.value.clone(), kinds: Arc::new([]) };
         let environment = self.ty.environment.clone();
         let ty = InEnvironment { value: canonical, environment };
         autoderef(db, Some(self.krate), ty)
@@ -1303,10 +1305,10 @@ impl Type {
         mut callback: impl FnMut(AssocItem) -> Option<T>,
     ) -> Option<T> {
         for krate in self.ty.value.def_crates(db, krate.id)? {
-            let impls = db.impls_in_crate(krate);
+            let impls = db.inherent_impls_in_crate(krate);
 
-            for impl_def in impls.lookup_impl_defs(&self.ty.value) {
-                for &item in db.impl_data(impl_def).items.iter() {
+            for impl_def in impls.for_self_ty(&self.ty.value) {
+                for &item in db.impl_data(*impl_def).items.iter() {
                     if let Some(result) = callback(item.into()) {
                         return Some(result);
                     }
@@ -1327,7 +1329,7 @@ impl Type {
         // There should be no inference vars in types passed here
         // FIXME check that?
         // FIXME replace Unknown by bound vars here
-        let canonical = Canonical { value: self.ty.value.clone(), num_vars: 0 };
+        let canonical = Canonical { value: self.ty.value.clone(), kinds: Arc::new([]) };
 
         let env = self.ty.environment.clone();
         let krate = krate.id;
@@ -1358,7 +1360,7 @@ impl Type {
         // There should be no inference vars in types passed here
         // FIXME check that?
         // FIXME replace Unknown by bound vars here
-        let canonical = Canonical { value: self.ty.value.clone(), num_vars: 0 };
+        let canonical = Canonical { value: self.ty.value.clone(), kinds: Arc::new([]) };
 
         let env = self.ty.environment.clone();
         let krate = krate.id;
diff --git a/crates/ra_hir/src/db.rs b/crates/ra_hir/src/db.rs
index bb67952de..cb48ca065 100644
--- a/crates/ra_hir/src/db.rs
+++ b/crates/ra_hir/src/db.rs
@@ -16,10 +16,10 @@ pub use hir_expand::db::{
 pub use hir_ty::db::{
     AssociatedTyDataQuery, AssociatedTyValueQuery, CallableItemSignatureQuery, FieldTypesQuery,
     GenericDefaultsQuery, GenericPredicatesForParamQuery, GenericPredicatesQuery, HirDatabase,
-    HirDatabaseStorage, ImplDatumQuery, ImplSelfTyQuery, ImplTraitQuery, ImplsFromDepsQuery,
-    ImplsInCrateQuery, InferQueryQuery, InternAssocTyValueQuery, InternChalkImplQuery,
-    InternTypeCtorQuery, InternTypeParamIdQuery, ReturnTypeImplTraitsQuery, StructDatumQuery,
-    TraitDatumQuery, TraitSolveQuery, TyQuery, ValueTyQuery,
+    HirDatabaseStorage, ImplDatumQuery, ImplSelfTyQuery, ImplTraitQuery, InferQueryQuery,
+    InherentImplsInCrateQuery, InternAssocTyValueQuery, InternChalkImplQuery, InternTypeCtorQuery,
+    InternTypeParamIdQuery, ReturnTypeImplTraitsQuery, StructDatumQuery, TraitDatumQuery,
+    TraitImplsInCrateQuery, TraitImplsInDepsQuery, TraitSolveQuery, TyQuery, ValueTyQuery,
 };
 
 #[test]
diff --git a/crates/ra_hir/src/semantics.rs b/crates/ra_hir/src/semantics.rs
index 6a49c424a..3d78f71c1 100644
--- a/crates/ra_hir/src/semantics.rs
+++ b/crates/ra_hir/src/semantics.rs
@@ -83,6 +83,11 @@ impl PathResolution {
 /// Primary API to get semantic information, like types, from syntax trees.
 pub struct Semantics<'db, DB> {
     pub db: &'db DB,
+    imp: SemanticsImpl<'db>,
+}
+
+pub struct SemanticsImpl<'db> {
+    pub db: &'db dyn HirDatabase,
     s2d_cache: RefCell<SourceToDefCache>,
     cache: RefCell<FxHashMap<SyntaxNode, HirFileId>>,
 }
@@ -95,20 +100,180 @@ impl<DB> fmt::Debug for Semantics<'_, DB> {
 
 impl<'db, DB: HirDatabase> Semantics<'db, DB> {
     pub fn new(db: &DB) -> Semantics<DB> {
-        Semantics { db, s2d_cache: Default::default(), cache: Default::default() }
+        let impl_ = SemanticsImpl::new(db);
+        Semantics { db, imp: impl_ }
     }
 
     pub fn parse(&self, file_id: FileId) -> ast::SourceFile {
-        let tree = self.db.parse(file_id).tree();
-        self.cache(tree.syntax().clone(), file_id.into());
-        tree
+        self.imp.parse(file_id)
     }
 
     pub fn ast<T: AstDiagnostic + Diagnostic>(&self, d: &T) -> <T as AstDiagnostic>::AST {
         let file_id = d.source().file_id;
         let root = self.db.parse_or_expand(file_id).unwrap();
-        self.cache(root, file_id);
-        d.ast(self.db)
+        self.imp.cache(root, file_id);
+        d.ast(self.db.upcast())
+    }
+
+    pub fn expand(&self, macro_call: &ast::MacroCall) -> Option<SyntaxNode> {
+        self.imp.expand(macro_call)
+    }
+
+    pub fn expand_hypothetical(
+        &self,
+        actual_macro_call: &ast::MacroCall,
+        hypothetical_args: &ast::TokenTree,
+        token_to_map: SyntaxToken,
+    ) -> Option<(SyntaxNode, SyntaxToken)> {
+        self.imp.expand_hypothetical(actual_macro_call, hypothetical_args, token_to_map)
+    }
+
+    pub fn descend_into_macros(&self, token: SyntaxToken) -> SyntaxToken {
+        self.imp.descend_into_macros(token)
+    }
+
+    pub fn descend_node_at_offset<N: ast::AstNode>(
+        &self,
+        node: &SyntaxNode,
+        offset: TextSize,
+    ) -> Option<N> {
+        self.imp.descend_node_at_offset(node, offset).find_map(N::cast)
+    }
+
+    pub fn original_range(&self, node: &SyntaxNode) -> FileRange {
+        self.imp.original_range(node)
+    }
+
+    pub fn diagnostics_range(&self, diagnostics: &dyn Diagnostic) -> FileRange {
+        self.imp.diagnostics_range(diagnostics)
+    }
+
+    pub fn ancestors_with_macros(&self, node: SyntaxNode) -> impl Iterator<Item = SyntaxNode> + '_ {
+        self.imp.ancestors_with_macros(node)
+    }
+
+    pub fn ancestors_at_offset_with_macros(
+        &self,
+        node: &SyntaxNode,
+        offset: TextSize,
+    ) -> impl Iterator<Item = SyntaxNode> + '_ {
+        self.imp.ancestors_at_offset_with_macros(node, offset)
+    }
+
+    /// Find a AstNode by offset inside SyntaxNode, if it is inside *Macrofile*,
+    /// search up until it is of the target AstNode type
+    pub fn find_node_at_offset_with_macros<N: AstNode>(
+        &self,
+        node: &SyntaxNode,
+        offset: TextSize,
+    ) -> Option<N> {
+        self.imp.ancestors_at_offset_with_macros(node, offset).find_map(N::cast)
+    }
+
+    /// Find a AstNode by offset inside SyntaxNode, if it is inside *MacroCall*,
+    /// descend it and find again
+    pub fn find_node_at_offset_with_descend<N: AstNode>(
+        &self,
+        node: &SyntaxNode,
+        offset: TextSize,
+    ) -> Option<N> {
+        if let Some(it) = find_node_at_offset(&node, offset) {
+            return Some(it);
+        }
+
+        self.imp.descend_node_at_offset(node, offset).find_map(N::cast)
+    }
+
+    pub fn type_of_expr(&self, expr: &ast::Expr) -> Option<Type> {
+        self.imp.type_of_expr(expr)
+    }
+
+    pub fn type_of_pat(&self, pat: &ast::Pat) -> Option<Type> {
+        self.imp.type_of_pat(pat)
+    }
+
+    pub fn resolve_method_call(&self, call: &ast::MethodCallExpr) -> Option<Function> {
+        self.imp.resolve_method_call(call)
+    }
+
+    pub fn resolve_field(&self, field: &ast::FieldExpr) -> Option<Field> {
+        self.imp.resolve_field(field)
+    }
+
+    pub fn resolve_record_field(&self, field: &ast::RecordField) -> Option<(Field, Option<Local>)> {
+        self.imp.resolve_record_field(field)
+    }
+
+    pub fn resolve_record_field_pat(&self, field: &ast::RecordFieldPat) -> Option<Field> {
+        self.imp.resolve_record_field_pat(field)
+    }
+
+    pub fn resolve_macro_call(&self, macro_call: &ast::MacroCall) -> Option<MacroDef> {
+        self.imp.resolve_macro_call(macro_call)
+    }
+
+    pub fn resolve_path(&self, path: &ast::Path) -> Option<PathResolution> {
+        self.imp.resolve_path(path)
+    }
+
+    pub fn resolve_variant(&self, record_lit: ast::RecordLit) -> Option<VariantId> {
+        self.imp.resolve_variant(record_lit)
+    }
+
+    pub fn lower_path(&self, path: &ast::Path) -> Option<Path> {
+        self.imp.lower_path(path)
+    }
+
+    pub fn resolve_bind_pat_to_const(&self, pat: &ast::BindPat) -> Option<ModuleDef> {
+        self.imp.resolve_bind_pat_to_const(pat)
+    }
+
+    // FIXME: use this instead?
+    // pub fn resolve_name_ref(&self, name_ref: &ast::NameRef) -> Option<???>;
+
+    pub fn record_literal_missing_fields(&self, literal: &ast::RecordLit) -> Vec<(Field, Type)> {
+        self.imp.record_literal_missing_fields(literal)
+    }
+
+    pub fn record_pattern_missing_fields(&self, pattern: &ast::RecordPat) -> Vec<(Field, Type)> {
+        self.imp.record_pattern_missing_fields(pattern)
+    }
+
+    pub fn to_def<T: ToDef>(&self, src: &T) -> Option<T::Def> {
+        let src = self.imp.find_file(src.syntax().clone()).with_value(src).cloned();
+        T::to_def(&self.imp, src)
+    }
+
+    pub fn to_module_def(&self, file: FileId) -> Option<Module> {
+        self.imp.to_module_def(file)
+    }
+
+    pub fn scope(&self, node: &SyntaxNode) -> SemanticsScope<'db> {
+        self.imp.scope(node)
+    }
+
+    pub fn scope_at_offset(&self, node: &SyntaxNode, offset: TextSize) -> SemanticsScope<'db> {
+        self.imp.scope_at_offset(node, offset)
+    }
+
+    pub fn scope_for_def(&self, def: Trait) -> SemanticsScope<'db> {
+        self.imp.scope_for_def(def)
+    }
+
+    pub fn assert_contains_node(&self, node: &SyntaxNode) {
+        self.imp.assert_contains_node(node)
+    }
+}
+
+impl<'db> SemanticsImpl<'db> {
+    pub fn new(db: &'db dyn HirDatabase) -> Self {
+        Self { db, s2d_cache: Default::default(), cache: Default::default() }
+    }
+
+    pub fn parse(&self, file_id: FileId) -> ast::SourceFile {
+        let tree = self.db.parse(file_id).tree();
+        self.cache(tree.syntax().clone(), file_id.into());
+        tree
     }
 
     pub fn expand(&self, macro_call: &ast::MacroCall) -> Option<SyntaxNode> {
@@ -130,9 +295,15 @@ impl<'db, DB: HirDatabase> Semantics<'db, DB> {
             self.find_file(actual_macro_call.syntax().clone()).with_value(actual_macro_call);
         let sa = self.analyze2(macro_call.map(|it| it.syntax()), None);
         let krate = sa.resolver.krate()?;
-        let macro_call_id = macro_call
-            .as_call_id(self.db, krate, |path| sa.resolver.resolve_path_as_macro(self.db, &path))?;
-        hir_expand::db::expand_hypothetical(self.db, macro_call_id, hypothetical_args, token_to_map)
+        let macro_call_id = macro_call.as_call_id(self.db.upcast(), krate, |path| {
+            sa.resolver.resolve_path_as_macro(self.db.upcast(), &path)
+        })?;
+        hir_expand::db::expand_hypothetical(
+            self.db.upcast(),
+            macro_call_id,
+            hypothetical_args,
+            token_to_map,
+        )
     }
 
     pub fn descend_into_macros(&self, token: SyntaxToken) -> SyntaxToken {
@@ -147,7 +318,7 @@ impl<'db, DB: HirDatabase> Semantics<'db, DB> {
                 return None;
             }
             let file_id = sa.expand(self.db, token.with_value(&macro_call))?;
-            let token = file_id.expansion_info(self.db)?.map_token_down(token.as_ref())?;
+            let token = file_id.expansion_info(self.db.upcast())?.map_token_down(token.as_ref())?;
 
             self.cache(find_root(&token.value.parent()), token.file_id);
 
@@ -159,15 +330,16 @@ impl<'db, DB: HirDatabase> Semantics<'db, DB> {
         token.value
     }
 
-    pub fn descend_node_at_offset<N: ast::AstNode>(
+    pub fn descend_node_at_offset(
         &self,
         node: &SyntaxNode,
         offset: TextSize,
-    ) -> Option<N> {
+    ) -> impl Iterator<Item = SyntaxNode> + '_ {
         // Handle macro token cases
         node.token_at_offset(offset)
             .map(|token| self.descend_into_macros(token))
-            .find_map(|it| self.ancestors_with_macros(it.parent()).find_map(N::cast))
+            .map(|it| self.ancestors_with_macros(it.parent()))
+            .flatten()
     }
 
     pub fn original_range(&self, node: &SyntaxNode) -> FileRange {
@@ -184,7 +356,7 @@ impl<'db, DB: HirDatabase> Semantics<'db, DB> {
 
     pub fn ancestors_with_macros(&self, node: SyntaxNode) -> impl Iterator<Item = SyntaxNode> + '_ {
         let node = self.find_file(node);
-        node.ancestors_with_macros(self.db).map(|it| it.value)
+        node.ancestors_with_macros(self.db.upcast()).map(|it| it.value)
     }
 
     pub fn ancestors_at_offset_with_macros(
@@ -197,29 +369,6 @@ impl<'db, DB: HirDatabase> Semantics<'db, DB> {
             .kmerge_by(|node1, node2| node1.text_range().len() < node2.text_range().len())
     }
 
-    /// Find a AstNode by offset inside SyntaxNode, if it is inside *Macrofile*,
-    /// search up until it is of the target AstNode type
-    pub fn find_node_at_offset_with_macros<N: AstNode>(
-        &self,
-        node: &SyntaxNode,
-        offset: TextSize,
-    ) -> Option<N> {
-        self.ancestors_at_offset_with_macros(node, offset).find_map(N::cast)
-    }
-
-    /// Find a AstNode by offset inside SyntaxNode, if it is inside *MacroCall*,
-    /// descend it and find again
-    pub fn find_node_at_offset_with_descend<N: AstNode>(
-        &self,
-        node: &SyntaxNode,
-        offset: TextSize,
-    ) -> Option<N> {
-        if let Some(it) = find_node_at_offset(&node, offset) {
-            return Some(it);
-        }
-        self.descend_node_at_offset(&node, offset)
-    }
-
     pub fn type_of_expr(&self, expr: &ast::Expr) -> Option<Type> {
         self.analyze(expr.syntax()).type_of(self.db, &expr)
     }
@@ -267,9 +416,6 @@ impl<'db, DB: HirDatabase> Semantics<'db, DB> {
         self.analyze(pat.syntax()).resolve_bind_pat_to_const(self.db, pat)
     }
 
-    // FIXME: use this instead?
-    // pub fn resolve_name_ref(&self, name_ref: &ast::NameRef) -> Option<???>;
-
     pub fn record_literal_missing_fields(&self, literal: &ast::RecordLit) -> Vec<(Field, Type)> {
         self.analyze(literal.syntax())
             .record_literal_missing_fields(self.db, literal)
@@ -282,11 +428,6 @@ impl<'db, DB: HirDatabase> Semantics<'db, DB> {
             .unwrap_or_default()
     }
 
-    pub fn to_def<T: ToDef>(&self, src: &T) -> Option<T::Def> {
-        let src = self.find_file(src.syntax().clone()).with_value(src).cloned();
-        T::to_def(self, src)
-    }
-
     fn with_ctx<F: FnOnce(&mut SourceToDefCtx) -> T, T>(&self, f: F) -> T {
         let mut cache = self.s2d_cache.borrow_mut();
         let mut ctx = SourceToDefCtx { db: self.db, cache: &mut *cache };
@@ -297,20 +438,20 @@ impl<'db, DB: HirDatabase> Semantics<'db, DB> {
         self.with_ctx(|ctx| ctx.file_to_def(file)).map(Module::from)
     }
 
-    pub fn scope(&self, node: &SyntaxNode) -> SemanticsScope<'db, DB> {
+    pub fn scope(&self, node: &SyntaxNode) -> SemanticsScope<'db> {
         let node = self.find_file(node.clone());
         let resolver = self.analyze2(node.as_ref(), None).resolver;
         SemanticsScope { db: self.db, resolver }
     }
 
-    pub fn scope_at_offset(&self, node: &SyntaxNode, offset: TextSize) -> SemanticsScope<'db, DB> {
+    pub fn scope_at_offset(&self, node: &SyntaxNode, offset: TextSize) -> SemanticsScope<'db> {
         let node = self.find_file(node.clone());
         let resolver = self.analyze2(node.as_ref(), Some(offset)).resolver;
         SemanticsScope { db: self.db, resolver }
     }
 
-    pub fn scope_for_def(&self, def: Trait) -> SemanticsScope<'db, DB> {
-        let resolver = def.id.resolver(self.db);
+    pub fn scope_for_def(&self, def: Trait) -> SemanticsScope<'db> {
+        let resolver = def.id.resolver(self.db.upcast());
         SemanticsScope { db: self.db, resolver }
     }
 
@@ -331,17 +472,17 @@ impl<'db, DB: HirDatabase> Semantics<'db, DB> {
             ChildContainer::DefWithBodyId(def) => {
                 return SourceAnalyzer::new_for_body(self.db, def, src, offset)
             }
-            ChildContainer::TraitId(it) => it.resolver(self.db),
-            ChildContainer::ImplId(it) => it.resolver(self.db),
-            ChildContainer::ModuleId(it) => it.resolver(self.db),
-            ChildContainer::EnumId(it) => it.resolver(self.db),
-            ChildContainer::VariantId(it) => it.resolver(self.db),
-            ChildContainer::GenericDefId(it) => it.resolver(self.db),
+            ChildContainer::TraitId(it) => it.resolver(self.db.upcast()),
+            ChildContainer::ImplId(it) => it.resolver(self.db.upcast()),
+            ChildContainer::ModuleId(it) => it.resolver(self.db.upcast()),
+            ChildContainer::EnumId(it) => it.resolver(self.db.upcast()),
+            ChildContainer::VariantId(it) => it.resolver(self.db.upcast()),
+            ChildContainer::GenericDefId(it) => it.resolver(self.db.upcast()),
         };
         SourceAnalyzer::new_for_resolver(resolver, src)
     }
 
-    fn cache(&self, root_node: SyntaxNode, file_id: HirFileId) {
+    pub fn cache(&self, root_node: SyntaxNode, file_id: HirFileId) {
         assert!(root_node.parent().is_none());
         let mut cache = self.cache.borrow_mut();
         let prev = cache.insert(root_node, file_id);
@@ -357,7 +498,7 @@ impl<'db, DB: HirDatabase> Semantics<'db, DB> {
         cache.get(root_node).copied()
     }
 
-    fn find_file(&self, node: SyntaxNode) -> InFile<SyntaxNode> {
+    pub fn find_file(&self, node: SyntaxNode) -> InFile<SyntaxNode> {
         let root_node = find_root(&node);
         let file_id = self.lookup(&root_node).unwrap_or_else(|| {
             panic!(
@@ -382,14 +523,14 @@ impl<'db, DB: HirDatabase> Semantics<'db, DB> {
 pub trait ToDef: AstNode + Clone {
     type Def;
 
-    fn to_def<DB: HirDatabase>(sema: &Semantics<DB>, src: InFile<Self>) -> Option<Self::Def>;
+    fn to_def(sema: &SemanticsImpl, src: InFile<Self>) -> Option<Self::Def>;
 }
 
 macro_rules! to_def_impls {
     ($(($def:path, $ast:path, $meth:ident)),* ,) => {$(
         impl ToDef for $ast {
             type Def = $def;
-            fn to_def<DB: HirDatabase>(sema: &Semantics<DB>, src: InFile<Self>) -> Option<Self::Def> {
+            fn to_def(sema: &SemanticsImpl, src: InFile<Self>) -> Option<Self::Def> {
                 sema.with_ctx(|ctx| ctx.$meth(src)).map(<$def>::from)
             }
         }
@@ -419,12 +560,12 @@ fn find_root(node: &SyntaxNode) -> SyntaxNode {
     node.ancestors().last().unwrap()
 }
 
-pub struct SemanticsScope<'a, DB> {
-    pub db: &'a DB,
+pub struct SemanticsScope<'a> {
+    pub db: &'a dyn HirDatabase,
     resolver: Resolver,
 }
 
-impl<'a, DB: HirDatabase> SemanticsScope<'a, DB> {
+impl<'a> SemanticsScope<'a> {
     pub fn module(&self) -> Option<Module> {
         Some(Module { id: self.resolver.module()? })
     }
@@ -433,13 +574,13 @@ impl<'a, DB: HirDatabase> SemanticsScope<'a, DB> {
     // FIXME: rename to visible_traits to not repeat scope?
     pub fn traits_in_scope(&self) -> FxHashSet<TraitId> {
         let resolver = &self.resolver;
-        resolver.traits_in_scope(self.db)
+        resolver.traits_in_scope(self.db.upcast())
     }
 
     pub fn process_all_names(&self, f: &mut dyn FnMut(Name, ScopeDef)) {
         let resolver = &self.resolver;
 
-        resolver.process_all_names(self.db, &mut |name, def| {
+        resolver.process_all_names(self.db.upcast(), &mut |name, def| {
             let def = match def {
                 resolver::ScopeDef::PerNs(it) => {
                     let items = ScopeDef::all_items(it);