3 files changed, 16 insertions, 21 deletions

diff --git a/crates/ra_hir_def/src/body/lower.rs b/crates/ra_hir_def/src/body/lower.rs
index bbde0b802..a74136b8e 100644
--- a/crates/ra_hir_def/src/body/lower.rs
+++ b/crates/ra_hir_def/src/body/lower.rs
@@ -27,7 +27,7 @@ use crate::{
         LogicOp, MatchArm, Ordering, Pat, PatId, RecordFieldPat, RecordLitField, Statement,
     },
     item_scope::BuiltinShadowMode,
-    item_tree::{FileItemTreeId, ItemTree, ItemTreeSource},
+    item_tree::{FileItemTreeId, ItemTree, ItemTreeNode},
     path::{GenericArgs, Path},
     type_ref::{Mutability, Rawness, TypeRef},
     AdtId, ConstLoc, ContainerId, DefWithBodyId, EnumLoc, FunctionLoc, Intern, ModuleDefId,
@@ -557,7 +557,7 @@ impl ExprCollector<'_> {
         }
     }
 
-    fn find_inner_item<S: ItemTreeSource>(&self, id: AstId<ast::ModuleItem>) -> FileItemTreeId<S> {
+    fn find_inner_item<S: ItemTreeNode>(&self, id: AstId<ast::ModuleItem>) -> FileItemTreeId<S> {
         let index =
             self.item_trees.iter().position(|(file, _)| *file == id.file_id).unwrap_or_else(|| {
                 panic!("couldn't find item tree for file {:?}", id.file_id);
diff --git a/crates/ra_hir_def/src/item_tree.rs b/crates/ra_hir_def/src/item_tree.rs
index 5beb11df7..a75271703 100644
--- a/crates/ra_hir_def/src/item_tree.rs
+++ b/crates/ra_hir_def/src/item_tree.rs
@@ -153,7 +153,7 @@ impl ItemTree {
         self.inner_items.values().flatten().copied()
     }
 
-    pub fn source<S: ItemTreeSource>(
+    pub fn source<S: ItemTreeNode>(
         &self,
         db: &dyn DefDatabase,
         of: FileItemTreeId<S>,
@@ -173,6 +173,10 @@ impl ItemTree {
 
 /// Trait implemented by all nodes in the item tree.
 pub trait ItemTreeNode: Clone {
+    type Source: AstNode + Into<ast::ModuleItem>;
+
+    fn ast_id(&self) -> FileAstId<Self::Source>;
+
     /// Looks up an instance of `Self` in an item tree.
     fn lookup(tree: &ItemTree, index: Idx<Self>) -> &Self;
 
@@ -183,13 +187,6 @@ pub trait ItemTreeNode: Clone {
     fn id_to_mod_item(id: FileItemTreeId<Self>) -> ModItem;
 }
 
-/// Trait for item tree nodes that allow accessing the original AST node.
-pub trait ItemTreeSource: ItemTreeNode {
-    type Source: AstNode + Into<ast::ModuleItem>;
-
-    fn ast_id(&self) -> FileAstId<Self::Source>;
-}
-
 pub struct FileItemTreeId<N: ItemTreeNode> {
     index: Idx<N>,
     _p: PhantomData<N>,
@@ -242,6 +239,12 @@ macro_rules! mod_items {
 
         $(
             impl ItemTreeNode for $typ {
+                type Source = $ast;
+
+                fn ast_id(&self) -> FileAstId<Self::Source> {
+                    self.ast_id
+                }
+
                 fn lookup(tree: &ItemTree, index: Idx<Self>) -> &Self {
                     &tree.$fld[index]
                 }
@@ -259,14 +262,6 @@ macro_rules! mod_items {
                 }
             }
 
-            impl ItemTreeSource for $typ {
-                type Source = $ast;
-
-                fn ast_id(&self) -> FileAstId<Self::Source> {
-                    self.ast_id
-                }
-            }
-
             impl Index<Idx<$typ>> for ItemTree {
                 type Output = $typ;
 
diff --git a/crates/ra_hir_def/src/src.rs b/crates/ra_hir_def/src/src.rs
index 10e21d48e..043b93fad 100644
--- a/crates/ra_hir_def/src/src.rs
+++ b/crates/ra_hir_def/src/src.rs
@@ -3,14 +3,14 @@
 use hir_expand::InFile;
 use ra_arena::map::ArenaMap;
 
-use crate::{db::DefDatabase, item_tree::ItemTreeSource, AssocItemLoc, ItemLoc};
+use crate::{db::DefDatabase, item_tree::ItemTreeNode, AssocItemLoc, ItemLoc};
 
 pub trait HasSource {
     type Value;
     fn source(&self, db: &dyn DefDatabase) -> InFile<Self::Value>;
 }
 
-impl<N: ItemTreeSource> HasSource for AssocItemLoc<N> {
+impl<N: ItemTreeNode> HasSource for AssocItemLoc<N> {
     type Value = N::Source;
 
     fn source(&self, db: &dyn DefDatabase) -> InFile<N::Source> {
@@ -23,7 +23,7 @@ impl<N: ItemTreeSource> HasSource for AssocItemLoc<N> {
     }
 }
 
-impl<N: ItemTreeSource> HasSource for ItemLoc<N> {
+impl<N: ItemTreeNode> HasSource for ItemLoc<N> {
     type Value = N::Source;
 
     fn source(&self, db: &dyn DefDatabase) -> InFile<N::Source> {