3 files changed, 45 insertions, 16 deletions

diff --git a/crates/hir/src/attrs.rs b/crates/hir/src/attrs.rs
index d32ce37ed..99fb65bac 100644
--- a/crates/hir/src/attrs.rs
+++ b/crates/hir/src/attrs.rs
@@ -3,15 +3,15 @@ use hir_def::{
     attr::{Attrs, Documentation},
     path::ModPath,
     resolver::HasResolver,
-    AttrDefId, ModuleDefId,
+    AttrDefId, GenericParamId, ModuleDefId,
 };
 use hir_expand::hygiene::Hygiene;
 use hir_ty::db::HirDatabase;
 use syntax::ast;
 
 use crate::{
-    Adt, Const, Enum, Field, Function, MacroDef, Module, ModuleDef, Static, Struct, Trait,
-    TypeAlias, Union, Variant,
+    Adt, Const, ConstParam, Enum, Field, Function, GenericParam, LifetimeParam, MacroDef, Module,
+    ModuleDef, Static, Struct, Trait, TypeAlias, TypeParam, Union, Variant,
 };
 
 pub trait HasAttrs {
@@ -62,25 +62,27 @@ impl_has_attrs![
     (Function, FunctionId),
     (Adt, AdtId),
     (Module, ModuleId),
+    (GenericParam, GenericParamId),
 ];
 
-macro_rules! impl_has_attrs_adt {
-    ($($adt:ident),*) => {$(
-        impl HasAttrs for $adt {
+macro_rules! impl_has_attrs_enum {
+    ($($variant:ident),* for $enum:ident) => {$(
+        impl HasAttrs for $variant {
             fn attrs(self, db: &dyn HirDatabase) -> Attrs {
-                Adt::$adt(self).attrs(db)
+                $enum::$variant(self).attrs(db)
             }
             fn docs(self, db: &dyn HirDatabase) -> Option<Documentation> {
-                Adt::$adt(self).docs(db)
+                $enum::$variant(self).docs(db)
             }
             fn resolve_doc_path(self, db: &dyn HirDatabase, link: &str, ns: Option<Namespace>) -> Option<ModuleDef> {
-                Adt::$adt(self).resolve_doc_path(db, link, ns)
+                $enum::$variant(self).resolve_doc_path(db, link, ns)
             }
         }
     )*};
 }
 
-impl_has_attrs_adt![Struct, Union, Enum];
+impl_has_attrs_enum![Struct, Union, Enum for Adt];
+impl_has_attrs_enum![TypeParam, ConstParam, LifetimeParam for GenericParam];
 
 fn resolve_doc_path(
     db: &dyn HirDatabase,
@@ -99,6 +101,12 @@ fn resolve_doc_path(
         AttrDefId::TraitId(it) => it.resolver(db.upcast()),
         AttrDefId::TypeAliasId(it) => it.resolver(db.upcast()),
         AttrDefId::ImplId(it) => it.resolver(db.upcast()),
+        AttrDefId::GenericParamId(it) => match it {
+            GenericParamId::TypeParamId(it) => it.parent,
+            GenericParamId::LifetimeParamId(it) => it.parent,
+            GenericParamId::ConstParamId(it) => it.parent,
+        }
+        .resolver(db.upcast()),
         AttrDefId::MacroDefId(_) => return None,
     };
     let path = ast::Path::parse(link).ok()?;
diff --git a/crates/hir/src/from_id.rs b/crates/hir/src/from_id.rs
index 2422887e3..3e47a5e9d 100644
--- a/crates/hir/src/from_id.rs
+++ b/crates/hir/src/from_id.rs
@@ -6,13 +6,13 @@
 use hir_def::{
     expr::{LabelId, PatId},
     item_scope::ItemInNs,
-    AdtId, AssocItemId, DefWithBodyId, EnumVariantId, FieldId, GenericDefId, ModuleDefId,
-    VariantId,
+    AdtId, AssocItemId, DefWithBodyId, EnumVariantId, FieldId, GenericDefId, GenericParamId,
+    ModuleDefId, VariantId,
 };
 
 use crate::{
-    Adt, AssocItem, DefWithBody, Field, GenericDef, Label, Local, MacroDef, ModuleDef, Variant,
-    VariantDef,
+    code_model::GenericParam, Adt, AssocItem, DefWithBody, Field, GenericDef, Label, Local,
+    MacroDef, ModuleDef, Variant, VariantDef,
 };
 
 macro_rules! from_id {
@@ -68,6 +68,26 @@ impl From<Adt> for AdtId {
     }
 }
 
+impl From<GenericParamId> for GenericParam {
+    fn from(id: GenericParamId) -> Self {
+        match id {
+            GenericParamId::TypeParamId(it) => GenericParam::TypeParam(it.into()),
+            GenericParamId::LifetimeParamId(it) => GenericParam::LifetimeParam(it.into()),
+            GenericParamId::ConstParamId(it) => GenericParam::ConstParam(it.into()),
+        }
+    }
+}
+
+impl From<GenericParam> for GenericParamId {
+    fn from(id: GenericParam) -> Self {
+        match id {
+            GenericParam::TypeParam(it) => GenericParamId::TypeParamId(it.id),
+            GenericParam::LifetimeParam(it) => GenericParamId::LifetimeParamId(it.id),
+            GenericParam::ConstParam(it) => GenericParamId::ConstParamId(it.id),
+        }
+    }
+}
+
 impl From<EnumVariantId> for Variant {
     fn from(id: EnumVariantId) -> Self {
         Variant { parent: id.parent.into(), id: id.local_id }
diff --git a/crates/hir/src/lib.rs b/crates/hir/src/lib.rs
index 8ac27e2dd..769945c47 100644
--- a/crates/hir/src/lib.rs
+++ b/crates/hir/src/lib.rs
@@ -35,8 +35,9 @@ pub use crate::{
     code_model::{
         Access, Adt, AsAssocItem, AssocItem, AssocItemContainer, Callable, CallableKind, Const,
         ConstParam, Crate, CrateDependency, DefWithBody, Enum, Field, FieldSource, Function,
-        GenericDef, HasVisibility, Impl, Label, LifetimeParam, Local, MacroDef, Module, ModuleDef,
-        ScopeDef, Static, Struct, Trait, Type, TypeAlias, TypeParam, Union, Variant, VariantDef,
+        GenericDef, GenericParam, HasVisibility, Impl, Label, LifetimeParam, Local, MacroDef,
+        Module, ModuleDef, ScopeDef, Static, Struct, Trait, Type, TypeAlias, TypeParam, Union,
+        Variant, VariantDef,
     },
     has_source::HasSource,
     semantics::{PathResolution, Semantics, SemanticsScope},