9 files changed, 261 insertions, 204 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..fc1a74641 100644
--- a/crates/hir/src/code_model.rs
+++ b/crates/hir/src/code_model.rs
@@ -6,7 +6,6 @@ use base_db::{CrateDisplayName, CrateId, Edition, FileId};
 use either::Either;
 use hir_def::{
     adt::{ReprKind, StructKind, VariantData},
-    builtin_type::BuiltinType,
     expr::{BindingAnnotation, LabelId, Pat, PatId},
     import_map,
     item_tree::ItemTreeNode,
@@ -15,11 +14,11 @@ use hir_def::{
     per_ns::PerNs,
     resolver::{HasResolver, Resolver},
     src::HasSource as _,
-    type_ref::{Mutability, TypeRef},
+    type_ref::TypeRef,
     AdtId, AssocContainerId, AssocItemId, AssocItemLoc, AttrDefId, ConstId, ConstParamId,
     DefWithBodyId, EnumId, FunctionId, GenericDefId, HasModule, ImplId, LifetimeParamId,
-    LocalEnumVariantId, LocalFieldId, LocalModuleId, Lookup, ModuleId, StaticId, StructId, TraitId,
-    TypeAliasId, TypeParamId, UnionId,
+    LocalEnumVariantId, LocalFieldId, Lookup, ModuleId, StaticId, StructId, TraitId, TypeAliasId,
+    TypeParamId, UnionId,
 };
 use hir_def::{find_path::PrefixKind, item_scope::ItemInNs, visibility::Visibility};
 use hir_expand::{
@@ -29,12 +28,12 @@ use hir_expand::{
 };
 use hir_ty::{
     autoderef,
-    display::{write_bounds_like_dyn_trait, HirDisplayError, HirFormatter},
+    display::{write_bounds_like_dyn_trait_with_prefix, HirDisplayError, HirFormatter},
     method_resolution,
     traits::{FnTrait, Solution, SolutionVariables},
-    ApplicationTy, BoundVar, CallableDefId, Canonical, DebruijnIndex, FnSig, GenericPredicate,
-    InEnvironment, Obligation, ProjectionPredicate, ProjectionTy, Substs, TraitEnvironment, Ty,
-    TyDefId, TyKind, TypeCtor,
+    AliasTy, BoundVar, CallableDefId, CallableSig, Canonical, DebruijnIndex, GenericPredicate,
+    InEnvironment, Mutability, Obligation, ProjectionPredicate, ProjectionTy, Scalar, Substs,
+    TraitEnvironment, Ty, TyDefId, TyVariableKind,
 };
 use rustc_hash::FxHashSet;
 use stdx::{format_to, impl_from};
@@ -90,8 +89,8 @@ impl Crate {
     }
 
     pub fn root_module(self, db: &dyn HirDatabase) -> Module {
-        let module_id = db.crate_def_map(self.id).root;
-        Module::new(self, module_id)
+        let def_map = db.crate_def_map(self.id);
+        Module { id: def_map.module_id(def_map.root()) }
     }
 
     pub fn root_file(self, db: &dyn HirDatabase) -> FileId {
@@ -245,7 +244,7 @@ impl ModuleDef {
             ModuleDef::Const(it) => it.name(db),
             ModuleDef::Static(it) => it.name(db),
 
-            ModuleDef::BuiltinType(it) => Some(it.as_name()),
+            ModuleDef::BuiltinType(it) => Some(it.name()),
         }
     }
 
@@ -270,18 +269,14 @@ impl ModuleDef {
             None => return,
         };
 
-        hir_ty::diagnostics::validate_module_item(db, module.id.krate, id, sink)
+        hir_ty::diagnostics::validate_module_item(db, module.id.krate(), id, sink)
     }
 }
 
 impl Module {
-    pub(crate) fn new(krate: Crate, crate_module_id: LocalModuleId) -> Module {
-        Module { id: ModuleId { krate: krate.id, local_id: crate_module_id } }
-    }
-
     /// Name of this module.
     pub fn name(self, db: &dyn HirDatabase) -> Option<Name> {
-        let def_map = db.crate_def_map(self.id.krate);
+        let def_map = self.id.def_map(db.upcast());
         let parent = def_map[self.id.local_id].parent?;
         def_map[parent].children.iter().find_map(|(name, module_id)| {
             if *module_id == self.id.local_id {
@@ -294,33 +289,34 @@ impl Module {
 
     /// Returns the crate this module is part of.
     pub fn krate(self) -> Crate {
-        Crate { id: self.id.krate }
+        Crate { id: self.id.krate() }
     }
 
     /// Topmost parent of this module. Every module has a `crate_root`, but some
     /// might be missing `krate`. This can happen if a module's file is not included
     /// 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)
+        let def_map = db.crate_def_map(self.id.krate());
+        Module { id: def_map.module_id(def_map.root()) }
     }
 
     /// Iterates over all child modules.
     pub fn children(self, db: &dyn HirDatabase) -> impl Iterator<Item = Module> {
-        let def_map = db.crate_def_map(self.id.krate);
+        let def_map = self.id.def_map(db.upcast());
         let children = def_map[self.id.local_id]
             .children
             .iter()
-            .map(|(_, module_id)| self.with_module_id(*module_id))
+            .map(|(_, module_id)| Module { id: def_map.module_id(*module_id) })
             .collect::<Vec<_>>();
         children.into_iter()
     }
 
     /// Finds a parent module.
     pub fn parent(self, db: &dyn HirDatabase) -> Option<Module> {
-        let def_map = db.crate_def_map(self.id.krate);
+        // FIXME: handle block expressions as modules (their parent is in a different DefMap)
+        let def_map = self.id.def_map(db.upcast());
         let parent_id = def_map[self.id.local_id].parent?;
-        Some(self.with_module_id(parent_id))
+        Some(Module { id: def_map.module_id(parent_id) })
     }
 
     pub fn path_to_root(self, db: &dyn HirDatabase) -> Vec<Module> {
@@ -339,7 +335,7 @@ impl Module {
         db: &dyn HirDatabase,
         visible_from: Option<Module>,
     ) -> Vec<(Name, ScopeDef)> {
-        db.crate_def_map(self.id.krate)[self.id.local_id]
+        self.id.def_map(db.upcast())[self.id.local_id]
             .scope
             .entries()
             .filter_map(|(name, def)| {
@@ -362,14 +358,14 @@ impl Module {
     }
 
     pub fn visibility_of(self, db: &dyn HirDatabase, def: &ModuleDef) -> Option<Visibility> {
-        db.crate_def_map(self.id.krate)[self.id.local_id].scope.visibility_of(def.clone().into())
+        self.id.def_map(db.upcast())[self.id.local_id].scope.visibility_of(def.clone().into())
     }
 
     pub fn diagnostics(self, db: &dyn HirDatabase, sink: &mut DiagnosticSink) {
         let _p = profile::span("Module::diagnostics").detail(|| {
             format!("{:?}", self.name(db).map_or("<unknown>".into(), |name| name.to_string()))
         });
-        let crate_def_map = db.crate_def_map(self.id.krate);
+        let crate_def_map = self.id.def_map(db.upcast());
         crate_def_map.add_diagnostics(db.upcast(), self.id.local_id, sink);
         for decl in self.declarations(db) {
             match decl {
@@ -396,19 +392,15 @@ impl Module {
     }
 
     pub fn declarations(self, db: &dyn HirDatabase) -> Vec<ModuleDef> {
-        let def_map = db.crate_def_map(self.id.krate);
+        let def_map = self.id.def_map(db.upcast());
         def_map[self.id.local_id].scope.declarations().map(ModuleDef::from).collect()
     }
 
     pub fn impl_defs(self, db: &dyn HirDatabase) -> Vec<Impl> {
-        let def_map = db.crate_def_map(self.id.krate);
+        let def_map = self.id.def_map(db.upcast());
         def_map[self.id.local_id].scope.impls().map(Impl::from).collect()
     }
 
-    pub(crate) fn with_module_id(self, module_id: LocalModuleId) -> Module {
-        Module::new(self.krate(), module_id)
-    }
-
     /// Finds a path that can be used to refer to the given item from within
     /// this module, if possible.
     pub fn find_use_path(self, db: &dyn DefDatabase, item: impl Into<ItemInNs>) -> Option<ModPath> {
@@ -457,7 +449,7 @@ impl Field {
         };
         let substs = Substs::type_params(db, generic_def_id);
         let ty = db.field_types(var_id)[self.id].clone().subst(&substs);
-        Type::new(db, self.parent.module(db).id.krate, var_id, ty)
+        Type::new(db, self.parent.module(db).id.krate(), var_id, ty)
     }
 
     pub fn parent_def(&self, _db: &dyn HirDatabase) -> VariantDef {
@@ -502,7 +494,11 @@ impl Struct {
     }
 
     pub fn ty(self, db: &dyn HirDatabase) -> Type {
-        Type::from_def(db, self.id.lookup(db.upcast()).container.module(db.upcast()).krate, self.id)
+        Type::from_def(
+            db,
+            self.id.lookup(db.upcast()).container.module(db.upcast()).krate(),
+            self.id,
+        )
     }
 
     pub fn repr(self, db: &dyn HirDatabase) -> Option<ReprKind> {
@@ -533,7 +529,11 @@ impl Union {
     }
 
     pub fn ty(self, db: &dyn HirDatabase) -> Type {
-        Type::from_def(db, self.id.lookup(db.upcast()).container.module(db.upcast()).krate, self.id)
+        Type::from_def(
+            db,
+            self.id.lookup(db.upcast()).container.module(db.upcast()).krate(),
+            self.id,
+        )
     }
 
     pub fn fields(self, db: &dyn HirDatabase) -> Vec<Field> {
@@ -573,7 +573,11 @@ impl Enum {
     }
 
     pub fn ty(self, db: &dyn HirDatabase) -> Type {
-        Type::from_def(db, self.id.lookup(db.upcast()).container.module(db.upcast()).krate, self.id)
+        Type::from_def(
+            db,
+            self.id.lookup(db.upcast()).container.module(db.upcast()).krate(),
+            self.id,
+        )
     }
 }
 
@@ -632,7 +636,7 @@ impl Adt {
     /// general set of completions, but will not look very nice when printed.
     pub fn ty(self, db: &dyn HirDatabase) -> Type {
         let id = AdtId::from(self);
-        Type::from_def(db, id.module(db.upcast()).krate, id)
+        Type::from_def(db, id.module(db.upcast()).krate(), id)
     }
 
     pub fn module(self, db: &dyn HirDatabase) -> Module {
@@ -750,7 +754,7 @@ impl Function {
         let ctx = hir_ty::TyLoweringContext::new(db, &resolver);
         let environment = TraitEnvironment::lower(db, &resolver);
         Type {
-            krate: self.id.lookup(db.upcast()).container.module(db.upcast()).krate,
+            krate: self.id.lookup(db.upcast()).container.module(db.upcast()).krate(),
             ty: InEnvironment { value: Ty::from_hir_ext(&ctx, ret_type).0, environment },
         }
     }
@@ -771,7 +775,7 @@ impl Function {
             .iter()
             .map(|type_ref| {
                 let ty = Type {
-                    krate: self.id.lookup(db.upcast()).container.module(db.upcast()).krate,
+                    krate: self.id.lookup(db.upcast()).container.module(db.upcast()).krate(),
                     ty: InEnvironment {
                         value: Ty::from_hir_ext(&ctx, type_ref).0,
                         environment: environment.clone(),
@@ -795,7 +799,7 @@ impl Function {
     }
 
     pub fn diagnostics(self, db: &dyn HirDatabase, sink: &mut DiagnosticSink) {
-        let krate = self.module(db).id.krate;
+        let krate = self.module(db).id.krate();
         hir_def::diagnostics::validate_body(db.upcast(), self.id.into(), sink);
         hir_ty::diagnostics::validate_module_item(db, krate, self.id.into(), sink);
         hir_ty::diagnostics::validate_body(db, self.id.into(), sink);
@@ -832,7 +836,7 @@ pub enum Access {
 impl From<Mutability> for Access {
     fn from(mutability: Mutability) -> Access {
         match mutability {
-            Mutability::Shared => Access::Shared,
+            Mutability::Not => Access::Shared,
             Mutability::Mut => Access::Exclusive,
         }
     }
@@ -861,7 +865,10 @@ impl SelfParam {
             .params
             .first()
             .map(|param| match *param {
-                TypeRef::Reference(.., mutability) => mutability.into(),
+                TypeRef::Reference(.., mutability) => match mutability {
+                    hir_def::type_ref::Mutability::Shared => Access::Shared,
+                    hir_def::type_ref::Mutability::Mut => Access::Exclusive,
+                },
                 _ => Access::Owned,
             })
             .unwrap_or(Access::Owned)
@@ -973,7 +980,7 @@ impl TypeAlias {
     }
 
     pub fn ty(self, db: &dyn HirDatabase) -> Type {
-        Type::from_def(db, self.id.lookup(db.upcast()).module(db.upcast()).krate, self.id)
+        Type::from_def(db, self.id.lookup(db.upcast()).module(db.upcast()).krate(), self.id)
     }
 
     pub fn name(self, db: &dyn HirDatabase) -> Name {
@@ -990,6 +997,23 @@ impl HasVisibility for TypeAlias {
 }
 
 #[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
+pub struct BuiltinType {
+    pub(crate) inner: hir_def::builtin_type::BuiltinType,
+}
+
+impl BuiltinType {
+    pub fn ty(self, db: &dyn HirDatabase, module: Module) -> Type {
+        let resolver = module.id.resolver(db.upcast());
+        Type::new_with_resolver(db, &resolver, Ty::builtin(self.inner))
+            .expect("crate not present in resolver")
+    }
+
+    pub fn name(self) -> Name {
+        self.inner.as_name()
+    }
+}
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
 pub struct MacroDef {
     pub(crate) id: MacroDefId,
 }
@@ -1000,8 +1024,9 @@ 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;
-        Some(Module::new(Crate { id: krate }, module_id))
+        let def_map = db.crate_def_map(krate);
+        let module_id = def_map.root();
+        Some(Module { id: def_map.module_id(module_id) })
     }
 
     /// XXX: this parses the file
@@ -1051,6 +1076,16 @@ 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 +1126,13 @@ 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 {
@@ -1213,7 +1255,7 @@ impl Local {
         let def = DefWithBodyId::from(self.parent);
         let infer = db.infer(def);
         let ty = infer[self.pat_id].clone();
-        let krate = def.module(db.upcast()).krate;
+        let krate = def.module(db.upcast()).krate();
         Type::new(db, krate, def, ty)
     }
 
@@ -1301,7 +1343,7 @@ impl TypeParam {
         let environment = TraitEnvironment::lower(db, &resolver);
         let ty = Ty::Placeholder(self.id);
         Type {
-            krate: self.id.parent.module(db.upcast()).krate,
+            krate: self.id.parent.module(db.upcast()).krate(),
             ty: InEnvironment { value: ty, environment },
         }
     }
@@ -1327,7 +1369,7 @@ impl TypeParam {
         let subst = Substs::type_params(db, self.id.parent);
         let ty = ty.subst(&subst.prefix(local_idx));
         Some(Type {
-            krate: self.id.parent.module(db.upcast()).krate,
+            krate: self.id.parent.module(db.upcast()).krate(),
             ty: InEnvironment { value: ty, environment },
         })
     }
@@ -1340,8 +1382,7 @@ impl HirDisplay for TypeParam {
         let substs = Substs::type_params(f.db, self.id.parent);
         let predicates = bounds.iter().cloned().map(|b| b.subst(&substs)).collect::<Vec<_>>();
         if !(predicates.is_empty() || f.omit_verbose_types()) {
-            write!(f, ": ")?;
-            write_bounds_like_dyn_trait(&predicates, f)?;
+            write_bounds_like_dyn_trait_with_prefix(":", &predicates, f)?;
         }
         Ok(())
     }
@@ -1388,7 +1429,7 @@ impl ConstParam {
 
     pub fn ty(self, db: &dyn HirDatabase) -> Type {
         let def = self.id.parent;
-        let krate = def.module(db.upcast()).krate;
+        let krate = def.module(db.upcast()).krate();
         Type::new(db, krate, def, db.const_param_ty(self.id))
     }
 }
@@ -1423,7 +1464,7 @@ impl Impl {
         let environment = TraitEnvironment::lower(db, &resolver);
         let ty = Ty::from_hir(&ctx, &impl_data.target_type);
         Type {
-            krate: self.id.lookup(db.upcast()).container.module(db.upcast()).krate,
+            krate: self.id.lookup(db.upcast()).container.module(db.upcast()).krate(),
             ty: InEnvironment { value: ty, environment },
         }
     }
@@ -1441,7 +1482,7 @@ impl Impl {
     }
 
     pub fn krate(self, db: &dyn HirDatabase) -> Crate {
-        Crate { id: self.module(db).id.krate }
+        Crate { id: self.module(db).id.krate() }
     }
 
     pub fn is_builtin_derive(self, db: &dyn HirDatabase) -> Option<InFile<ast::Attr>> {
@@ -1509,25 +1550,19 @@ impl Type {
     }
 
     pub fn is_unit(&self) -> bool {
-        matches!(
-            self.ty.value,
-            Ty::Apply(ApplicationTy { ctor: TypeCtor::Tuple { cardinality: 0 }, .. })
-        )
+        matches!(self.ty.value, Ty::Tuple(0, ..))
     }
     pub fn is_bool(&self) -> bool {
-        matches!(self.ty.value, Ty::Apply(ApplicationTy { ctor: TypeCtor::Bool, .. }))
+        matches!(self.ty.value, Ty::Scalar(Scalar::Bool))
     }
 
     pub fn is_mutable_reference(&self) -> bool {
-        matches!(
-            self.ty.value,
-            Ty::Apply(ApplicationTy { ctor: TypeCtor::Ref(Mutability::Mut), .. })
-        )
+        matches!(self.ty.value, Ty::Ref(Mutability::Mut, ..))
     }
 
     pub fn remove_ref(&self) -> Option<Type> {
-        if let Ty::Apply(ApplicationTy { ctor: TypeCtor::Ref(_), .. }) = self.ty.value {
-            self.ty.value.substs().map(|substs| self.derived(substs[0].clone()))
+        if let Ty::Ref(.., substs) = &self.ty.value {
+            Some(self.derived(substs[0].clone()))
         } else {
             None
         }
@@ -1616,14 +1651,14 @@ impl Type {
             .build();
         let predicate = ProjectionPredicate {
             projection_ty: ProjectionTy { associated_ty: alias.id, parameters: subst },
-            ty: Ty::Bound(BoundVar::new(DebruijnIndex::INNERMOST, 0)),
+            ty: Ty::BoundVar(BoundVar::new(DebruijnIndex::INNERMOST, 0)),
         };
         let goal = Canonical {
             value: InEnvironment::new(
                 self.ty.environment.clone(),
                 Obligation::Projection(predicate),
             ),
-            kinds: Arc::new([TyKind::General]),
+            kinds: Arc::new([TyVariableKind::General]),
         };
 
         match db.trait_solve(self.krate, goal)? {
@@ -1647,7 +1682,7 @@ impl Type {
 
     pub fn as_callable(&self, db: &dyn HirDatabase) -> Option<Callable> {
         let def = match self.ty.value {
-            Ty::Apply(ApplicationTy { ctor: TypeCtor::FnDef(def), parameters: _ }) => Some(def),
+            Ty::FnDef(def, _) => Some(def),
             _ => None,
         };
 
@@ -1656,20 +1691,16 @@ impl Type {
     }
 
     pub fn is_closure(&self) -> bool {
-        matches!(&self.ty.value, Ty::Apply(ApplicationTy { ctor: TypeCtor::Closure { .. }, .. }))
+        matches!(&self.ty.value, Ty::Closure { .. })
     }
 
     pub fn is_fn(&self) -> bool {
-        matches!(
-            &self.ty.value,
-            Ty::Apply(ApplicationTy { ctor: TypeCtor::FnDef(..), .. })
-                | Ty::Apply(ApplicationTy { ctor: TypeCtor::FnPtr { .. }, .. })
-        )
+        matches!(&self.ty.value, Ty::FnDef(..) | Ty::Function { .. })
     }
 
     pub fn is_packed(&self, db: &dyn HirDatabase) -> bool {
         let adt_id = match self.ty.value {
-            Ty::Apply(ApplicationTy { ctor: TypeCtor::Adt(adt_id), .. }) => adt_id,
+            Ty::Adt(adt_id, ..) => adt_id,
             _ => return false,
         };
 
@@ -1681,7 +1712,7 @@ impl Type {
     }
 
     pub fn is_raw_ptr(&self) -> bool {
-        matches!(&self.ty.value, Ty::Apply(ApplicationTy { ctor: TypeCtor::RawPtr(..), .. }))
+        matches!(&self.ty.value, Ty::Raw(..))
     }
 
     pub fn contains_unknown(&self) -> bool {
@@ -1690,44 +1721,34 @@ impl Type {
         fn go(ty: &Ty) -> bool {
             match ty {
                 Ty::Unknown => true,
-                Ty::Apply(a_ty) => a_ty.parameters.iter().any(go),
-                _ => false,
+                _ => ty.substs().map_or(false, |substs| substs.iter().any(go)),
             }
         }
     }
 
     pub fn fields(&self, db: &dyn HirDatabase) -> Vec<(Field, Type)> {
-        if let Ty::Apply(a_ty) = &self.ty.value {
-            let variant_id = match a_ty.ctor {
-                TypeCtor::Adt(AdtId::StructId(s)) => s.into(),
-                TypeCtor::Adt(AdtId::UnionId(u)) => u.into(),
-                _ => return Vec::new(),
-            };
-
-            return db
-                .field_types(variant_id)
-                .iter()
-                .map(|(local_id, ty)| {
-                    let def = Field { parent: variant_id.into(), id: local_id };
-                    let ty = ty.clone().subst(&a_ty.parameters);
-                    (def, self.derived(ty))
-                })
-                .collect();
+        let (variant_id, substs) = match self.ty.value {
+            Ty::Adt(AdtId::StructId(s), ref substs) => (s.into(), substs),
+            Ty::Adt(AdtId::UnionId(u), ref substs) => (u.into(), substs),
+            _ => return Vec::new(),
         };
-        Vec::new()
+
+        db.field_types(variant_id)
+            .iter()
+            .map(|(local_id, ty)| {
+                let def = Field { parent: variant_id.into(), id: local_id };
+                let ty = ty.clone().subst(substs);
+                (def, self.derived(ty))
+            })
+            .collect()
     }
 
     pub fn tuple_fields(&self, _db: &dyn HirDatabase) -> Vec<Type> {
-        let mut res = Vec::new();
-        if let Ty::Apply(a_ty) = &self.ty.value {
-            if let TypeCtor::Tuple { .. } = a_ty.ctor {
-                for ty in a_ty.parameters.iter() {
-                    let ty = ty.clone();
-                    res.push(self.derived(ty));
-                }
-            }
-        };
-        res
+        if let Ty::Tuple(_, substs) = &self.ty.value {
+            substs.iter().map(|ty| self.derived(ty.clone())).collect()
+        } else {
+            Vec::new()
+        }
     }
 
     pub fn autoderef<'a>(&'a self, db: &'a dyn HirDatabase) -> impl Iterator<Item = Type> + 'a {
@@ -1763,6 +1784,16 @@ impl Type {
         None
     }
 
+    pub fn type_parameters(&self) -> impl Iterator<Item = Type> + '_ {
+        self.ty
+            .value
+            .strip_references()
+            .substs()
+            .into_iter()
+            .flat_map(|substs| substs.iter())
+            .map(move |ty| self.derived(ty.clone()))
+    }
+
     pub fn iterate_method_candidates<T>(
         &self,
         db: &dyn HirDatabase,
@@ -1850,17 +1881,8 @@ impl Type {
 
     // FIXME: provide required accessors such that it becomes implementable from outside.
     pub fn is_equal_for_find_impls(&self, other: &Type) -> bool {
-        match (&self.ty.value, &other.ty.value) {
-            (Ty::Apply(a_original_ty), Ty::Apply(ApplicationTy { ctor, parameters })) => match ctor
-            {
-                TypeCtor::Ref(..) => match parameters.as_single() {
-                    Ty::Apply(a_ty) => a_original_ty.ctor == a_ty.ctor,
-                    _ => false,
-                },
-                _ => a_original_ty.ctor == *ctor,
-            },
-            _ => false,
-        }
+        let rref = other.remove_ref();
+        self.ty.value.equals_ctor(rref.as_ref().map_or(&other.ty.value, |it| &it.ty.value))
     }
 
     fn derived(&self, ty: Ty) -> Type {
@@ -1905,28 +1927,20 @@ impl Type {
         fn walk_type(db: &dyn HirDatabase, type_: &Type, cb: &mut impl FnMut(Type)) {
             let ty = type_.ty.value.strip_references();
             match ty {
-                Ty::Apply(ApplicationTy { ctor, parameters }) => {
-                    match ctor {
-                        TypeCtor::Adt(_) => {
-                            cb(type_.derived(ty.clone()));
-                        }
-                        TypeCtor::AssociatedType(_) => {
-                            if let Some(_) = ty.associated_type_parent_trait(db) {
-                                cb(type_.derived(ty.clone()));
-                            }
-                        }
-                        TypeCtor::OpaqueType(..) => {
-                            if let Some(bounds) = ty.impl_trait_bounds(db) {
-                                walk_bounds(db, &type_.derived(ty.clone()), &bounds, cb);
-                            }
-                        }
-                        _ => (),
+                Ty::Adt(..) => {
+                    cb(type_.derived(ty.clone()));
+                }
+                Ty::AssociatedType(..) => {
+                    if let Some(_) = ty.associated_type_parent_trait(db) {
+                        cb(type_.derived(ty.clone()));
                     }
-
-                    // adt params, tuples, etc...
-                    walk_substs(db, type_, parameters, cb);
                 }
-                Ty::Opaque(opaque_ty) => {
+                Ty::OpaqueType(..) => {
+                    if let Some(bounds) = ty.impl_trait_bounds(db) {
+                        walk_bounds(db, &type_.derived(ty.clone()), &bounds, cb);
+                    }
+                }
+                Ty::Alias(AliasTy::Opaque(opaque_ty)) => {
                     if let Some(bounds) = ty.impl_trait_bounds(db) {
                         walk_bounds(db, &type_.derived(ty.clone()), &bounds, cb);
                     }
@@ -1942,7 +1956,10 @@ impl Type {
                     walk_bounds(db, &type_.derived(ty.clone()), bounds.as_ref(), cb);
                 }
 
-                _ => (),
+                _ => {}
+            }
+            if let Some(substs) = ty.substs() {
+                walk_substs(db, type_, &substs, cb);
             }
         }
 
@@ -1960,7 +1977,7 @@ impl HirDisplay for Type {
 #[derive(Debug)]
 pub struct Callable {
     ty: Type,
-    sig: FnSig,
+    sig: CallableSig,
     def: Option<CallableDefId>,
     pub(crate) is_bound_method: bool,
 }
@@ -2025,11 +2042,11 @@ impl Callable {
 }
 
 /// For IDE only
-#[derive(Debug)]
+#[derive(Debug, PartialEq, Eq, Hash)]
 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/diagnostics.rs b/crates/hir/src/diagnostics.rs
index 447faa04f..b1ebba516 100644
--- a/crates/hir/src/diagnostics.rs
+++ b/crates/hir/src/diagnostics.rs
@@ -1,9 +1,11 @@
 //! FIXME: write short doc here
-pub use hir_def::diagnostics::{InactiveCode, UnresolvedModule, UnresolvedProcMacro};
+pub use hir_def::diagnostics::{
+    InactiveCode, UnresolvedMacroCall, UnresolvedModule, UnresolvedProcMacro,
+};
 pub use hir_expand::diagnostics::{
     Diagnostic, DiagnosticCode, DiagnosticSink, DiagnosticSinkBuilder,
 };
 pub use hir_ty::diagnostics::{
     IncorrectCase, MismatchedArgCount, MissingFields, MissingMatchArms, MissingOkOrSomeInTailExpr,
-    NoSuchField, RemoveThisSemicolon,
+    NoSuchField, RemoveThisSemicolon, ReplaceFilterMapNextWithFindMap,
 };
diff --git a/crates/hir/src/from_id.rs b/crates/hir/src/from_id.rs
index c8c5fecd7..b5814da11 100644
--- a/crates/hir/src/from_id.rs
+++ b/crates/hir/src/from_id.rs
@@ -11,8 +11,9 @@ use hir_def::{
 };
 
 use crate::{
-    code_model::GenericParam, Adt, AssocItem, DefWithBody, Field, GenericDef, Label, Local,
-    MacroDef, ModuleDef, Variant, VariantDef,
+    code_model::{BuiltinType, GenericParam},
+    Adt, AssocItem, DefWithBody, Field, GenericDef, Label, Local, MacroDef, ModuleDef, Variant,
+    VariantDef,
 };
 
 macro_rules! from_id {
@@ -111,7 +112,7 @@ impl From<ModuleDefId> for ModuleDef {
             ModuleDefId::StaticId(it) => ModuleDef::Static(it.into()),
             ModuleDefId::TraitId(it) => ModuleDef::Trait(it.into()),
             ModuleDefId::TypeAliasId(it) => ModuleDef::TypeAlias(it.into()),
-            ModuleDefId::BuiltinType(it) => ModuleDef::BuiltinType(it),
+            ModuleDefId::BuiltinType(it) => ModuleDef::BuiltinType(it.into()),
         }
     }
 }
@@ -127,7 +128,7 @@ impl From<ModuleDef> for ModuleDefId {
             ModuleDef::Static(it) => ModuleDefId::StaticId(it.into()),
             ModuleDef::Trait(it) => ModuleDefId::TraitId(it.into()),
             ModuleDef::TypeAlias(it) => ModuleDefId::TypeAliasId(it.into()),
-            ModuleDef::BuiltinType(it) => ModuleDefId::BuiltinType(it),
+            ModuleDef::BuiltinType(it) => ModuleDefId::BuiltinType(it.into()),
         }
     }
 }
@@ -274,3 +275,15 @@ impl From<ModuleDef> for ItemInNs {
         }
     }
 }
+
+impl From<hir_def::builtin_type::BuiltinType> for BuiltinType {
+    fn from(inner: hir_def::builtin_type::BuiltinType) -> Self {
+        Self { inner }
+    }
+}
+
+impl From<BuiltinType> for hir_def::builtin_type::BuiltinType {
+    fn from(it: BuiltinType) -> Self {
+        it.inner
+    }
+}
diff --git a/crates/hir/src/has_source.rs b/crates/hir/src/has_source.rs
index 7c57d8378..262002671 100644
--- a/crates/hir/src/has_source.rs
+++ b/crates/hir/src/has_source.rs
@@ -24,12 +24,12 @@ pub trait HasSource {
 impl Module {
     /// Returns a node which defines this module. That is, a file or a `mod foo {}` with items.
     pub fn definition_source(self, db: &dyn HirDatabase) -> InFile<ModuleSource> {
-        let def_map = db.crate_def_map(self.id.krate);
+        let def_map = self.id.def_map(db.upcast());
         def_map[self.id.local_id].definition_source(db.upcast())
     }
 
     pub fn is_mod_rs(self, db: &dyn HirDatabase) -> bool {
-        let def_map = db.crate_def_map(self.id.krate);
+        let def_map = self.id.def_map(db.upcast());
         match def_map[self.id.local_id].origin {
             ModuleOrigin::File { is_mod_rs, .. } => is_mod_rs,
             _ => false,
@@ -39,7 +39,7 @@ impl Module {
     /// Returns a node which declares this module, either a `mod foo;` or a `mod foo {}`.
     /// `None` for the crate root.
     pub fn declaration_source(self, db: &dyn HirDatabase) -> Option<InFile<ast::Module>> {
-        let def_map = db.crate_def_map(self.id.krate);
+        let def_map = self.id.def_map(db.upcast());
         def_map[self.id.local_id].declaration_source(db.upcast())
     }
 }
diff --git a/crates/hir/src/semantics.rs b/crates/hir/src/semantics.rs
index ab213e04c..144851f83 100644
--- a/crates/hir/src/semantics.rs
+++ b/crates/hir/src/semantics.rs
@@ -16,13 +16,12 @@ use rustc_hash::{FxHashMap, FxHashSet};
 use syntax::{
     algo::find_node_at_offset,
     ast::{self, GenericParamsOwner, LoopBodyOwner},
-    match_ast, AstNode, SyntaxNode, SyntaxToken, TextSize,
+    match_ast, AstNode, SyntaxNode, SyntaxNodePtr, SyntaxToken, TextSize,
 };
 
 use crate::{
     code_model::Access,
     db::HirDatabase,
-    diagnostics::Diagnostic,
     semantics::source_to_def::{ChildContainer, SourceToDefCache, SourceToDefCtx},
     source_analyzer::{resolve_hir_path, SourceAnalyzer},
     AssocItem, Callable, ConstParam, Crate, Field, Function, HirFileId, Impl, InFile, Label,
@@ -49,7 +48,7 @@ impl PathResolution {
         match self {
             PathResolution::Def(ModuleDef::Adt(adt)) => Some(TypeNs::AdtId((*adt).into())),
             PathResolution::Def(ModuleDef::BuiltinType(builtin)) => {
-                Some(TypeNs::BuiltinType(*builtin))
+                Some(TypeNs::BuiltinType((*builtin).into()))
             }
             PathResolution::Def(ModuleDef::Const(_))
             | PathResolution::Def(ModuleDef::Variant(_))
@@ -141,7 +140,7 @@ impl<'db, DB: HirDatabase> Semantics<'db, DB> {
         self.imp.original_range(node)
     }
 
-    pub fn diagnostics_display_range(&self, diagnostics: &dyn Diagnostic) -> FileRange {
+    pub fn diagnostics_display_range(&self, diagnostics: InFile<SyntaxNodePtr>) -> FileRange {
         self.imp.diagnostics_display_range(diagnostics)
     }
 
@@ -385,8 +384,7 @@ impl<'db> SemanticsImpl<'db> {
         node.as_ref().original_file_range(self.db.upcast())
     }
 
-    fn diagnostics_display_range(&self, diagnostics: &dyn Diagnostic) -> FileRange {
-        let src = diagnostics.display_source();
+    fn diagnostics_display_range(&self, src: InFile<SyntaxNodePtr>) -> FileRange {
         let root = self.db.parse_or_expand(src.file_id).unwrap();
         let node = src.value.to_node(&root);
         self.cache(root, src.file_id);
@@ -814,7 +812,7 @@ 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 })
diff --git a/crates/hir/src/semantics/source_to_def.rs b/crates/hir/src/semantics/source_to_def.rs
index 9bf60c72a..6c612ee86 100644
--- a/crates/hir/src/semantics/source_to_def.rs
+++ b/crates/hir/src/semantics/source_to_def.rs
@@ -30,12 +30,12 @@ pub(super) struct SourceToDefCtx<'a, 'b> {
 impl SourceToDefCtx<'_, '_> {
     pub(super) fn file_to_def(&mut self, file: FileId) -> Option<ModuleId> {
         let _p = profile::span("SourceBinder::to_module_def");
-        let (krate, local_id) = self.db.relevant_crates(file).iter().find_map(|&crate_id| {
+        self.db.relevant_crates(file).iter().find_map(|&crate_id| {
+            // FIXME: inner items
             let crate_def_map = self.db.crate_def_map(crate_id);
             let local_id = crate_def_map.modules_for_file(file).next()?;
-            Some((crate_id, local_id))
-        })?;
-        Some(ModuleId { krate, local_id })
+            Some(crate_def_map.module_id(local_id))
+        })
     }
 
     pub(super) fn module_to_def(&mut self, src: InFile<ast::Module>) -> Option<ModuleId> {
@@ -60,9 +60,9 @@ impl SourceToDefCtx<'_, '_> {
         }?;
 
         let child_name = src.value.name()?.as_name();
-        let def_map = self.db.crate_def_map(parent_module.krate);
+        let def_map = parent_module.def_map(self.db.upcast());
         let child_id = *def_map[parent_module.local_id].children.get(&child_name)?;
-        Some(ModuleId { krate: parent_module.krate, local_id: child_id })
+        Some(def_map.module_id(child_id))
     }
 
     pub(super) fn trait_to_def(&mut self, src: InFile<ast::Trait>) -> Option<TraitId> {
@@ -185,7 +185,7 @@ impl SourceToDefCtx<'_, '_> {
     ) -> Option<MacroDefId> {
         let kind = MacroDefKind::Declarative;
         let file_id = src.file_id.original_file(self.db.upcast());
-        let krate = self.file_to_def(file_id)?.krate;
+        let krate = self.file_to_def(file_id)?.krate();
         let file_ast_id = self.db.ast_id_map(src.file_id).ast_id(&src.value);
         let ast_id = Some(AstId::new(src.file_id, file_ast_id.upcast()));
         Some(MacroDefId { krate, ast_id, kind, local_inner: false })
diff --git a/crates/hir/src/source_analyzer.rs b/crates/hir/src/source_analyzer.rs
index 30a8e513d..64ce4add1 100644
--- a/crates/hir/src/source_analyzer.rs
+++ b/crates/hir/src/source_analyzer.rs
@@ -20,7 +20,7 @@ use hir_def::{
 use hir_expand::{hygiene::Hygiene, name::AsName, HirFileId, InFile};
 use hir_ty::{
     diagnostics::{record_literal_missing_fields, record_pattern_missing_fields},
-    InferenceResult, Substs, Ty,
+    InferenceResult, Substs,
 };
 use syntax::{
     ast::{self, AstNode},
@@ -28,8 +28,9 @@ use syntax::{
 };
 
 use crate::{
-    db::HirDatabase, semantics::PathResolution, Adt, Const, Field, Function, Local, MacroDef,
-    ModuleDef, Static, Struct, Trait, Type, TypeAlias, TypeParam, Variant,
+    code_model::BuiltinType, db::HirDatabase, semantics::PathResolution, Adt, Const, Field,
+    Function, Local, MacroDef, ModuleDef, Static, Struct, Trait, Type, TypeAlias, TypeParam,
+    Variant,
 };
 use base_db::CrateId;
 
@@ -222,19 +223,23 @@ impl SourceAnalyzer {
         db: &dyn HirDatabase,
         path: &ast::Path,
     ) -> Option<PathResolution> {
-        if let Some(path_expr) = path.syntax().parent().and_then(ast::PathExpr::cast) {
+        let parent = || path.syntax().parent();
+        let mut prefer_value_ns = false;
+        if let Some(path_expr) = parent().and_then(ast::PathExpr::cast) {
             let expr_id = self.expr_id(db, &path_expr.into())?;
-            if let Some(assoc) = self.infer.as_ref()?.assoc_resolutions_for_expr(expr_id) {
+            let infer = self.infer.as_ref()?;
+            if let Some(assoc) = infer.assoc_resolutions_for_expr(expr_id) {
                 return Some(PathResolution::AssocItem(assoc.into()));
             }
             if let Some(VariantId::EnumVariantId(variant)) =
-                self.infer.as_ref()?.variant_resolution_for_expr(expr_id)
+                infer.variant_resolution_for_expr(expr_id)
             {
                 return Some(PathResolution::Def(ModuleDef::Variant(variant.into())));
             }
+            prefer_value_ns = true;
         }
 
-        if let Some(path_pat) = path.syntax().parent().and_then(ast::PathPat::cast) {
+        if let Some(path_pat) = parent().and_then(ast::PathPat::cast) {
             let pat_id = self.pat_id(&path_pat.into())?;
             if let Some(assoc) = self.infer.as_ref()?.assoc_resolutions_for_pat(pat_id) {
                 return Some(PathResolution::AssocItem(assoc.into()));
@@ -246,7 +251,7 @@ impl SourceAnalyzer {
             }
         }
 
-        if let Some(rec_lit) = path.syntax().parent().and_then(ast::RecordExpr::cast) {
+        if let Some(rec_lit) = parent().and_then(ast::RecordExpr::cast) {
             let expr_id = self.expr_id(db, &rec_lit.into())?;
             if let Some(VariantId::EnumVariantId(variant)) =
                 self.infer.as_ref()?.variant_resolution_for_expr(expr_id)
@@ -255,8 +260,12 @@ impl SourceAnalyzer {
             }
         }
 
-        if let Some(rec_pat) = path.syntax().parent().and_then(ast::RecordPat::cast) {
-            let pat_id = self.pat_id(&rec_pat.into())?;
+        if let Some(pat) = parent()
+            .and_then(ast::RecordPat::cast)
+            .map(ast::Pat::from)
+            .or_else(|| parent().and_then(ast::TupleStructPat::cast).map(ast::Pat::from))
+        {
+            let pat_id = self.pat_id(&pat)?;
             if let Some(VariantId::EnumVariantId(variant)) =
                 self.infer.as_ref()?.variant_resolution_for_pat(pat_id)
             {
@@ -269,7 +278,7 @@ impl SourceAnalyzer {
 
         // Case where path is a qualifier of another path, e.g. foo::bar::Baz where we
         // trying to resolve foo::bar.
-        if let Some(outer_path) = path.syntax().parent().and_then(ast::Path::cast) {
+        if let Some(outer_path) = parent().and_then(ast::Path::cast) {
             if let Some(qualifier) = outer_path.qualifier() {
                 if path == &qualifier {
                     return resolve_hir_path_qualifier(db, &self.resolver, &hir_path);
@@ -277,7 +286,7 @@ impl SourceAnalyzer {
             }
         }
 
-        resolve_hir_path(db, &self.resolver, &hir_path)
+        resolve_hir_path_(db, &self.resolver, &hir_path, prefer_value_ns)
     }
 
     pub(crate) fn record_literal_missing_fields(
@@ -290,14 +299,11 @@ impl SourceAnalyzer {
         let infer = self.infer.as_ref()?;
 
         let expr_id = self.expr_id(db, &literal.clone().into())?;
-        let substs = match &infer.type_of_expr[expr_id] {
-            Ty::Apply(a_ty) => &a_ty.parameters,
-            _ => return None,
-        };
+        let substs = infer.type_of_expr[expr_id].substs()?;
 
         let (variant, missing_fields, _exhaustive) =
             record_literal_missing_fields(db, infer, expr_id, &body[expr_id])?;
-        let res = self.missing_fields(db, krate, substs, variant, missing_fields);
+        let res = self.missing_fields(db, krate, &substs, variant, missing_fields);
         Some(res)
     }
 
@@ -311,14 +317,11 @@ impl SourceAnalyzer {
         let infer = self.infer.as_ref()?;
 
         let pat_id = self.pat_id(&pattern.clone().into())?;
-        let substs = match &infer.type_of_pat[pat_id] {
-            Ty::Apply(a_ty) => &a_ty.parameters,
-            _ => return None,
-        };
+        let substs = infer.type_of_pat[pat_id].substs()?;
 
         let (variant, missing_fields, _exhaustive) =
             record_pattern_missing_fields(db, infer, pat_id, &body[pat_id])?;
-        let res = self.missing_fields(db, krate, substs, variant, missing_fields);
+        let res = self.missing_fields(db, krate, &substs, variant, missing_fields);
         Some(res)
     }
 
@@ -447,12 +450,22 @@ fn adjust(
         .map(|(_ptr, scope)| *scope)
 }
 
+#[inline]
 pub(crate) fn resolve_hir_path(
     db: &dyn HirDatabase,
     resolver: &Resolver,
     path: &Path,
 ) -> Option<PathResolution> {
-    let types =
+    resolve_hir_path_(db, resolver, path, false)
+}
+
+fn resolve_hir_path_(
+    db: &dyn HirDatabase,
+    resolver: &Resolver,
+    path: &Path,
+    prefer_value_ns: bool,
+) -> Option<PathResolution> {
+    let types = || {
         resolver.resolve_path_in_type_ns_fully(db.upcast(), path.mod_path()).map(|ty| match ty {
             TypeNs::SelfType(it) => PathResolution::SelfType(it.into()),
             TypeNs::GenericParam(id) => PathResolution::TypeParam(TypeParam { id }),
@@ -461,12 +474,13 @@ pub(crate) fn resolve_hir_path(
             }
             TypeNs::EnumVariantId(it) => PathResolution::Def(Variant::from(it).into()),
             TypeNs::TypeAliasId(it) => PathResolution::Def(TypeAlias::from(it).into()),
-            TypeNs::BuiltinType(it) => PathResolution::Def(it.into()),
+            TypeNs::BuiltinType(it) => PathResolution::Def(BuiltinType::from(it).into()),
             TypeNs::TraitId(it) => PathResolution::Def(Trait::from(it).into()),
-        });
+        })
+    };
 
     let body_owner = resolver.body_owner();
-    let values =
+    let values = || {
         resolver.resolve_path_in_value_ns_fully(db.upcast(), path.mod_path()).and_then(|val| {
             let res = match val {
                 ValueNs::LocalBinding(pat_id) => {
@@ -482,18 +496,25 @@ pub(crate) fn resolve_hir_path(
                 ValueNs::GenericParam(it) => PathResolution::ConstParam(it.into()),
             };
             Some(res)
-        });
+        })
+    };
 
-    let items = resolver
-        .resolve_module_path_in_items(db.upcast(), path.mod_path())
-        .take_types()
-        .map(|it| PathResolution::Def(it.into()));
+    let items = || {
+        resolver
+            .resolve_module_path_in_items(db.upcast(), path.mod_path())
+            .take_types()
+            .map(|it| PathResolution::Def(it.into()))
+    };
 
-    types.or(values).or(items).or_else(|| {
+    let macros = || {
         resolver
             .resolve_path_as_macro(db.upcast(), path.mod_path())
             .map(|def| PathResolution::Macro(def.into()))
-    })
+    };
+
+    if prefer_value_ns { values().or_else(types) } else { types().or_else(values) }
+        .or_else(items)
+        .or_else(macros)
 }
 
 /// Resolves a path where we know it is a qualifier of another path.
@@ -529,7 +550,7 @@ fn resolve_hir_path_qualifier(
         TypeNs::AdtSelfType(it) | TypeNs::AdtId(it) => PathResolution::Def(Adt::from(it).into()),
         TypeNs::EnumVariantId(it) => PathResolution::Def(Variant::from(it).into()),
         TypeNs::TypeAliasId(it) => PathResolution::Def(TypeAlias::from(it).into()),
-        TypeNs::BuiltinType(it) => PathResolution::Def(it.into()),
+        TypeNs::BuiltinType(it) => PathResolution::Def(BuiltinType::from(it).into()),
         TypeNs::TraitId(it) => PathResolution::Def(Trait::from(it).into()),
     })
 }