internal: remove one more usage of old editing API.

crates/ide_assists/src/utils.rs

@@ -130,7 +130,8 @@ pub fn add_trait_assoc_items_to_impl(
     let items = items.into_iter().map(|assoc_item| {
         let assoc_item = assoc_item.clone_for_update();
         transform.apply(assoc_item.syntax());
-        edit::remove_attrs_and_docs(&assoc_item).clone_subtree().clone_for_update()
+        edit::remove_attrs_and_docs(&assoc_item);
+        assoc_item
     });
 
     let res = impl_.clone_for_update();

crates/ide_completion/src/completions/trait_impl.rs

@@ -194,10 +194,10 @@ fn get_transformed_assoc_item(
     );
 
     transform.apply(assoc_item.syntax());
-    Some(match assoc_item {
-        ast::AssocItem::Fn(func) => ast::AssocItem::Fn(edit::remove_attrs_and_docs(&func)),
-        _ => assoc_item,
-    })
+    if let ast::AssocItem::Fn(func) = &assoc_item {
+        edit::remove_attrs_and_docs(func)
+    }
+    Some(assoc_item)
 }
 
 fn add_type_alias_impl(
@@ -253,7 +253,7 @@ fn add_const_impl(
 }
 
 fn make_const_compl_syntax(const_: &ast::Const) -> String {
-    let const_ = edit::remove_attrs_and_docs(const_);
+    edit::remove_attrs_and_docs(const_);
 
     let const_start = const_.syntax().text_range().start();
     let const_end = const_.syntax().text_range().end();

crates/syntax/src/algo.rs

@@ -1,6 +1,6 @@
 //! Collection of assorted algorithms for syntax trees.
 
-use std::{hash::BuildHasherDefault, ops::RangeInclusive};
+use std::hash::BuildHasherDefault;
 
 use indexmap::IndexMap;
 use itertools::Itertools;
@@ -295,41 +295,6 @@ fn _insert_children(
     with_children(parent, new_children)
 }
 
-/// Replaces all nodes in `to_delete` with nodes from `to_insert`
-///
-/// This is a type-unsafe low-level editing API, if you need to use it,
-/// prefer to create a type-safe abstraction on top of it instead.
-pub fn replace_children(
-    parent: &SyntaxNode,
-    to_delete: RangeInclusive<SyntaxElement>,
-    to_insert: impl IntoIterator<Item = SyntaxElement>,
-) -> SyntaxNode {
-    let mut to_insert = to_insert.into_iter();
-    _replace_children(parent, to_delete, &mut to_insert)
-}
-
-fn _replace_children(
-    parent: &SyntaxNode,
-    to_delete: RangeInclusive<SyntaxElement>,
-    to_insert: &mut dyn Iterator<Item = SyntaxElement>,
-) -> SyntaxNode {
-    let start = position_of_child(parent, to_delete.start().clone());
-    let end = position_of_child(parent, to_delete.end().clone());
-    let parent_green = parent.green();
-    let mut old_children = parent_green.children().map(|it| match it {
-        NodeOrToken::Token(it) => NodeOrToken::Token(it.to_owned()),
-        NodeOrToken::Node(it) => NodeOrToken::Node(it.to_owned()),
-    });
-
-    let before = old_children.by_ref().take(start).collect::<Vec<_>>();
-    let new_children = before
-        .into_iter()
-        .chain(to_insert.map(to_green_element))
-        .chain(old_children.skip(end + 1 - start))
-        .collect::<Vec<_>>();
-    with_children(parent, new_children)
-}
-
 fn with_children(
     parent: &SyntaxNode,
     new_children: Vec<NodeOrToken<rowan::GreenNode, rowan::GreenToken>>,

crates/syntax/src/ast/edit.rs

@@ -48,22 +48,26 @@ impl ast::UseTree {
     }
 }
 
-#[must_use]
-pub fn remove_attrs_and_docs<N: ast::AttrsOwner>(node: &N) -> N {
-    N::cast(remove_attrs_and_docs_inner(node.syntax().clone())).unwrap()
+pub fn remove_attrs_and_docs<N: ast::AttrsOwner>(node: &N) {
+    remove_attrs_and_docs_inner(node.syntax())
 }
 
-fn remove_attrs_and_docs_inner(mut node: SyntaxNode) -> SyntaxNode {
-    while let Some(start) =
-        node.children_with_tokens().find(|it| it.kind() == ATTR || it.kind() == COMMENT)
-    {
-        let end = match &start.next_sibling_or_token() {
-            Some(el) if el.kind() == WHITESPACE => el.clone(),
-            Some(_) | None => start.clone(),
-        };
-        node = algo::replace_children(&node, start..=end, &mut iter::empty());
+fn remove_attrs_and_docs_inner(node: &SyntaxNode) {
+    let mut remove_next_ws = false;
+    for child in node.children_with_tokens() {
+        match child.kind() {
+            ATTR | COMMENT => {
+                remove_next_ws = true;
+                child.detach();
+                continue;
+            }
+            WHITESPACE if remove_next_ws => {
+                child.detach();
+            }
+            _ => (),
+        }
+        remove_next_ws = false;
     }
-    node
 }
 
 #[derive(Debug, Clone, Copy)]