migrate add impl items to the new editing API

3 files changed, 15 insertions, 77 deletions

diff --git a/crates/ra_assists/src/assist_ctx.rs b/crates/ra_assists/src/assist_ctx.rs
index c45262efa..cbe12e908 100644
--- a/crates/ra_assists/src/assist_ctx.rs
+++ b/crates/ra_assists/src/assist_ctx.rs
@@ -2,7 +2,7 @@ use hir::db::HirDatabase;
 use ra_db::FileRange;
 use ra_fmt::{leading_indent, reindent};
 use ra_syntax::{
-    algo::{find_covering_element, find_node_at_offset},
+    algo::{self, find_covering_element, find_node_at_offset},
     AstNode, SourceFile, SyntaxElement, SyntaxNode, SyntaxToken, TextRange, TextUnit,
     TokenAtOffset,
 };
@@ -177,6 +177,12 @@ impl AssistBuilder {
         &mut self.edit
     }
 
+    pub(crate) fn replace_ast<N: AstNode>(&mut self, old: N, new: N) {
+        for (from, to) in algo::diff(old.syntax(), new.syntax()) {
+            self.edit.replace(from.text_range(), to.to_string())
+        }
+    }
+
     fn build(self) -> AssistAction {
         AssistAction {
             edit: self.edit.finish(),
diff --git a/crates/ra_assists/src/assists/add_missing_impl_members.rs b/crates/ra_assists/src/assists/add_missing_impl_members.rs
index 3fce4a5b7..c2e3eb06b 100644
--- a/crates/ra_assists/src/assists/add_missing_impl_members.rs
+++ b/crates/ra_assists/src/assists/add_missing_impl_members.rs
@@ -4,7 +4,7 @@ use ra_syntax::{
     SmolStr,
 };
 
-use crate::{ast_editor::AstEditor, Assist, AssistCtx, AssistId};
+use crate::{Assist, AssistCtx, AssistId};
 
 #[derive(PartialEq)]
 enum AddMissingImplMembersMode {
@@ -79,14 +79,13 @@ fn add_missing_impl_members_inner(
             ast::ImplItem::FnDef(def) => edit::strip_attrs_and_docs(add_body(def).into()),
             _ => edit::strip_attrs_and_docs(it),
         });
-        let mut ast_editor = AstEditor::new(impl_item_list);
-
-        ast_editor.append_items(items);
-
-        let first_new_item = ast_editor.ast().impl_items().nth(n_existing_items).unwrap();
-        let cursor_position = first_new_item.syntax().text_range().start();
-        ast_editor.into_text_edit(edit.text_edit_builder());
+        let new_impl_item_list = impl_item_list.append_items(items);
+        let cursor_position = {
+            let first_new_item = new_impl_item_list.impl_items().nth(n_existing_items).unwrap();
+            first_new_item.syntax().text_range().start()
+        };
 
+        edit.replace_ast(impl_item_list, new_impl_item_list);
         edit.set_cursor(cursor_position);
     });
 
diff --git a/crates/ra_assists/src/ast_editor.rs b/crates/ra_assists/src/ast_editor.rs
index 60b8923e1..262e2fcf4 100644
--- a/crates/ra_assists/src/ast_editor.rs
+++ b/crates/ra_assists/src/ast_editor.rs
@@ -7,9 +7,7 @@ use ra_fmt::leading_indent;
 use ra_syntax::{
     algo,
     ast::{self, make::tokens, TypeBoundsOwner},
-    AstNode, Direction, InsertPosition, SyntaxElement,
-    SyntaxKind::*,
-    T,
+    AstNode, Direction, InsertPosition, SyntaxElement, T,
 };
 use ra_text_edit::TextEditBuilder;
 
@@ -67,38 +65,6 @@ impl<N: AstNode> AstEditor<N> {
         let new_syntax = algo::replace_children(self.ast().syntax(), to_delete, &mut to_insert);
         N::cast(new_syntax).unwrap()
     }
-
-    fn do_make_multiline(&mut self) {
-        let l_curly =
-            match self.ast().syntax().children_with_tokens().find(|it| it.kind() == T!['{']) {
-                Some(it) => it,
-                None => return,
-            };
-        let sibling = match l_curly.next_sibling_or_token() {
-            Some(it) => it,
-            None => return,
-        };
-        let existing_ws = match sibling.as_token() {
-            None => None,
-            Some(tok) if tok.kind() != WHITESPACE => None,
-            Some(ws) => {
-                if ws.text().contains('\n') {
-                    return;
-                }
-                Some(ws.clone())
-            }
-        };
-
-        let indent = leading_indent(self.ast().syntax()).unwrap_or("".into());
-        let ws = tokens::WsBuilder::new(&format!("\n{}", indent));
-        let to_insert = iter::once(ws.ws().into());
-        self.ast = match existing_ws {
-            None => self.insert_children(InsertPosition::After(l_curly), to_insert),
-            Some(ws) => {
-                self.replace_children(RangeInclusive::new(ws.clone().into(), ws.into()), to_insert)
-            }
-        };
-    }
 }
 
 impl AstEditor<ast::RecordFieldList> {
@@ -179,39 +145,6 @@ impl AstEditor<ast::RecordFieldList> {
     }
 }
 
-impl AstEditor<ast::ItemList> {
-    pub fn append_items(&mut self, items: impl Iterator<Item = ast::ImplItem>) {
-        if !self.ast().syntax().text().contains_char('\n') {
-            self.do_make_multiline();
-        }
-        items.for_each(|it| self.append_item(it));
-    }
-
-    pub fn append_item(&mut self, item: ast::ImplItem) {
-        let (indent, position) = match self.ast().impl_items().last() {
-            Some(it) => (
-                leading_indent(it.syntax()).unwrap_or_default().to_string(),
-                InsertPosition::After(it.syntax().clone().into()),
-            ),
-            None => match self.l_curly() {
-                Some(it) => (
-                    "    ".to_string() + &leading_indent(self.ast().syntax()).unwrap_or_default(),
-                    InsertPosition::After(it),
-                ),
-                None => return,
-            },
-        };
-        let ws = tokens::WsBuilder::new(&format!("\n{}", indent));
-        let to_insert: ArrayVec<[SyntaxElement; 2]> =
-            [ws.ws().into(), item.syntax().clone().into()].into();
-        self.ast = self.insert_children(position, to_insert.into_iter());
-    }
-
-    fn l_curly(&self) -> Option<SyntaxElement> {
-        self.ast().syntax().children_with_tokens().find(|it| it.kind() == T!['{'])
-    }
-}
-
 impl AstEditor<ast::TypeParam> {
     pub fn remove_bounds(&mut self) -> &mut Self {
         let colon = match self.ast.colon_token() {