Introduce hir::GenericParam

Unlike existing hir::GenericParams, this is a global ID.

crates/ra_hir/src/code_model.rs

@@ -23,7 +23,7 @@ use crate::{
     adt::VariantDef,
     db::{AstDatabase, DefDatabase, HirDatabase},
     expr::{validation::ExprValidator, BindingAnnotation, Body, BodySourceMap, Pat, PatId},
-    generics::HasGenericParams,
+    generics::{GenericDef, HasGenericParams},
     ids::{
         AstItemDef, ConstId, EnumId, FunctionId, MacroDefId, StaticId, StructId, TraitId,
         TypeAliasId,
@@ -1121,3 +1121,9 @@ impl Local {
         src.map(|ast| ast.map(|it| it.cast().unwrap().to_node(&root), |it| it.to_node(&root)))
     }
 }
+
+#[derive(Clone, Copy, Debug, PartialEq, Eq, Hash)]
+pub struct GenericParam {
+    pub(crate) parent: GenericDef,
+    pub(crate) idx: u32,
+}

crates/ra_hir/src/lib.rs

@@ -65,8 +65,8 @@ pub use crate::{
         docs::{DocDef, Docs, Documentation},
         src::{HasBodySource, HasSource},
         Adt, AssocItem, Const, ConstData, Container, Crate, CrateDependency, DefWithBody, Enum,
-        EnumVariant, FieldSource, FnData, Function, HasBody, Local, MacroDef, Module, ModuleDef,
-        ModuleSource, Static, Struct, StructField, Trait, TypeAlias, Union,
+        EnumVariant, FieldSource, FnData, Function, GenericParam, HasBody, Local, MacroDef, Module,
+        ModuleDef, ModuleSource, Static, Struct, StructField, Trait, TypeAlias, Union,
     },
     expr::ExprScopes,
     from_source::FromSource,

crates/ra_hir/src/source_binder.rs

@@ -28,8 +28,8 @@ use crate::{
     ids::LocationCtx,
     resolve::{ScopeDef, TypeNs, ValueNs},
     ty::method_resolution::{self, implements_trait},
-    AssocItem, Const, DefWithBody, Either, Enum, FromSource, Function, HasBody, HirFileId, Local,
-    MacroDef, Module, Name, Path, Resolver, Static, Struct, Ty,
+    AssocItem, Const, DefWithBody, Either, Enum, FromSource, Function, GenericParam, HasBody,
+    HirFileId, Local, MacroDef, Module, Name, Path, Resolver, Static, Struct, Ty,
 };
 
 fn try_get_resolver_for_node(
@@ -107,7 +107,7 @@ pub enum PathResolution {
     /// A local binding (only value namespace)
     Local(Local),
     /// A generic parameter
-    GenericParam(u32),
+    GenericParam(GenericParam),
     SelfType(crate::ImplBlock),
     Macro(MacroDef),
     AssocItem(crate::AssocItem),
@@ -227,7 +227,10 @@ impl SourceAnalyzer {
     ) -> Option<PathResolution> {
         let types = self.resolver.resolve_path_in_type_ns_fully(db, &path).map(|ty| match ty {
             TypeNs::SelfType(it) => PathResolution::SelfType(it),
-            TypeNs::GenericParam(it) => PathResolution::GenericParam(it),
+            TypeNs::GenericParam(idx) => PathResolution::GenericParam(GenericParam {
+                parent: self.resolver.generic_def().unwrap(),
+                idx,
+            }),
             TypeNs::AdtSelfType(it) | TypeNs::Adt(it) => PathResolution::Def(it.into()),
             TypeNs::EnumVariant(it) => PathResolution::Def(it.into()),
             TypeNs::TypeAlias(it) => PathResolution::Def(it.into()),

crates/ra_ide_api/src/references/name_definition.rs

@@ -4,7 +4,8 @@
 //! Note that the reference search is possible for not all of the classified items.
 
 use hir::{
-    Adt, AssocItem, HasSource, Local, MacroDef, Module, ModuleDef, StructField, Ty, VariantDef,
+    Adt, AssocItem, GenericParam, HasSource, Local, MacroDef, Module, ModuleDef, StructField, Ty,
+    VariantDef,
 };
 use ra_syntax::{ast, ast::VisibilityOwner};
 
@@ -18,7 +19,7 @@ pub enum NameKind {
     Def(ModuleDef),
     SelfType(Ty),
     Local(Local),
-    GenericParam(u32),
+    GenericParam(GenericParam),
 }
 
 #[derive(PartialEq, Eq)]