fix: no generate with default assoc item

crates/ide-assists/src/handlers/generate_blanket_trait_impl.rs

@@ -15,7 +15,7 @@ use syntax::{
         self, AssocItem, GenericParam, HasAttrs, HasGenericParams, HasName, HasTypeBounds,
         HasVisibility, edit::AstNodeEdit, syntax_factory::SyntaxFactory,
     },
-    syntax_editor::Position,
+    syntax_editor::{Position, Removable},
 };
 
 // Assist: generate_blanket_trait_impl
@@ -99,10 +99,15 @@ pub(crate) fn generate_blanket_trait_impl(
                             ast::AssocItem::Fn(method) if method.body().is_none() => {
                                 todo_fn(make, &method, ctx.config).into()
                             }
-                            ast::AssocItem::Const(_) | ast::AssocItem::TypeAlias(_) => item,
+                            ast::AssocItem::Const(it) if it.body().is_none() => {
+                                ast::AssocItem::Const(it.reset_indent())
+                            }
+                            ast::AssocItem::TypeAlias(it) if it.ty().is_none() => {
+                                remove_bounds(it.reset_indent()).into()
+                            }
                             _ => return None,
                         };
-                        Some(item.reset_indent().indent(1.into()))
+                        Some(item.indent(1.into()))
                     })
                     .collect::<Vec<_>>();
                 (!items.is_empty()).then(|| make.assoc_item_list(items))
@@ -284,6 +289,16 @@ fn todo_fn(make: &SyntaxFactory, f: &ast::Fn, config: &AssistConfig) -> ast::Fn
     )
 }
 
+fn remove_bounds(alias: ast::TypeAlias) -> ast::TypeAlias {
+    let (editor, alias) = syntax::syntax_editor::SyntaxEditor::with_ast_node(&alias);
+
+    if let Some(type_bound_list) = alias.type_bound_list() {
+        type_bound_list.remove(&editor);
+    }
+
+    ast::TypeAlias::cast(editor.finish().new_root().clone()).unwrap()
+}
+
 fn cfg_attrs(node: &impl HasAttrs) -> impl Iterator<Item = ast::Attr> {
     node.attrs().filter(|attr| matches!(attr.meta(), Some(ast::Meta::CfgMeta(_))))
 }
@@ -533,6 +548,33 @@ impl<T: ?Sized> Foo for $0T {
         );
     }
 
+    #[test]
+    fn test_gen_blanket_assoc_items_with_default() {
+        check_assist(
+            generate_blanket_trait_impl,
+            r#"
+trait $0Foo {
+    type Item = ();
+
+    const N: usize = 3;
+
+    fn foo(&self) {}
+}
+"#,
+            r#"
+trait Foo {
+    type Item = ();
+
+    const N: usize = 3;
+
+    fn foo(&self) {}
+}
+
+impl<T: ?Sized> Foo for $0T {}
+"#,
+        );
+    }
+
     #[test]
     fn test_gen_blanket_indent() {
         check_assist(
@@ -775,7 +817,7 @@ mod foo {
 mod foo {
     mod bar {
         trait $0Foo {
-            type Item: Bar<
+            type Item where Self: Bar<
                 Self,
             >;
 
@@ -790,7 +832,7 @@ mod foo {
 mod foo {
     mod bar {
         trait Foo {
-            type Item: Bar<
+            type Item where Self: Bar<
                 Self,
             >;
 
@@ -800,7 +842,7 @@ mod foo {
         }
 
         impl<T: ?Sized> Foo for $0T {
-            type Item: Bar<
+            type Item where Self: Bar<
                 Self,
             >;
 
@@ -894,7 +936,7 @@ impl<T: Send, T1: ToOwned + ?Sized> Foo<T> for $0T1
 where
     Self::Owned: Default,
 {
-    type X: Sync;
+    type X;
 
     fn foo(&self, x: Self::X) -> T {
         todo!()
@@ -943,7 +985,7 @@ where
     Self: ToOwned,
     Self::Owned: Default,
 {
-    type X: Sync;
+    type X;
 
     fn foo(&self, x: Self::X) -> T {
         todo!()
@@ -980,7 +1022,7 @@ trait Foo<T: Send> {
 }
 
 impl<T: Send, T1: ?Sized> Foo<T> for $0T1 {
-    type X: Sync;
+    type X;
 
     fn foo(&self, x: Self::X) -> T {
         todo!()
@@ -1017,7 +1059,7 @@ trait Foo {
 }
 
 impl<T: ?Sized> Foo for $0T {
-    type X: Sync;
+    type X;
 
     fn foo(&self, x: Self::X) -> i32 {
         todo!()