feat: define EditorRemovable trait

Signed-off-by: Tarek <[email protected]>

Author: tareknaser

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

@@ -6,7 +6,7 @@ use ide_db::imports::{
 use itertools::Itertools;
 use syntax::{
     algo::neighbor,
-    ast::{self, edit_in_place::Removable, syntax_factory::SyntaxFactory},
+    ast::{self, edit_in_place::EditorRemovable, syntax_factory::SyntaxFactory},
     match_ast, AstNode, SyntaxElement, SyntaxNode,
 };
 
@@ -81,17 +81,16 @@ pub(crate) fn merge_imports(acc: &mut Assists, ctx: &AssistContext<'_>) -> Optio
         target,
         |builder| {
             let mut editor = builder.make_editor(&parent_node);
-            let edits_mut: Vec<Edit> = edits
-                .into_iter()
-                .map(|it| match it {
-                    Remove(Either::Left(it)) => Remove(Either::Left(builder.make_mut(it))),
-                    Remove(Either::Right(it)) => Remove(Either::Right(builder.make_mut(it))),
-                    Replace(old, new) => Replace(builder.make_syntax_mut(old), new),
-                })
-                .collect();
-            for edit in edits_mut {
+            for edit in edits {
                 match edit {
-                    Remove(it) => it.as_ref().either(Removable::remove, Removable::remove),
+                    Remove(it) => {
+                        let node = it.as_ref();
+                        if let Some(left) = node.left() {
+                            left.remove(&mut editor);
+                        } else if let Some(right) = node.right() {
+                            right.remove(&mut editor);
+                        }
+                    }
                     Replace(old, new) => {
                         editor.replace(old, &new);
 

crates/syntax/src/ast/edit_in_place.rs

@@ -6,7 +6,11 @@ use parser::{SyntaxKind, T};
 
 use crate::{
     algo::{self, neighbor},
-    ast::{self, edit::IndentLevel, make, HasGenericArgs, HasGenericParams},
+    ast::{
+        self, edit::IndentLevel, make, syntax_factory::SyntaxFactory, HasGenericArgs,
+        HasGenericParams,
+    },
+    syntax_editor::SyntaxEditor,
     ted::{self, Position},
     AstNode, AstToken, Direction, SyntaxElement,
     SyntaxKind::{ATTR, COMMENT, WHITESPACE},
@@ -385,6 +389,10 @@ pub trait Removable: AstNode {
     fn remove(&self);
 }
 
+pub trait EditorRemovable: AstNode {
+    fn remove(&self, editor: &mut SyntaxEditor);
+}
+
 impl Removable for ast::TypeBoundList {
     fn remove(&self) {
         match self.syntax().siblings_with_tokens(Direction::Prev).find(|it| it.kind() == T![:]) {
@@ -439,16 +447,35 @@ impl Removable for ast::UseTree {
     }
 }
 
+impl EditorRemovable for ast::UseTree {
+    fn remove(&self, editor: &mut SyntaxEditor) {
+        for dir in [Direction::Next, Direction::Prev] {
+            if let Some(next_use_tree) = neighbor(self, dir) {
+                let separators = self
+                    .syntax()
+                    .siblings_with_tokens(dir)
+                    .skip(1)
+                    .take_while(|it| it.as_node() != Some(next_use_tree.syntax()));
+                for sep in separators {
+                    editor.delete(sep);
+                }
+                break;
+            }
+        }
+        editor.delete(self.syntax());
+    }
+}
+
 impl ast::UseTree {
     /// Deletes the usetree node represented by the input. Recursively removes parents, including use nodes that become empty.
     pub fn remove_recursive(self) {
         let parent = self.syntax().parent();
 
-        self.remove();
+        Removable::remove(&self);
 
         if let Some(u) = parent.clone().and_then(ast::Use::cast) {
             if u.use_tree().is_none() {
-                u.remove();
+                Removable::remove(&u);
             }
         } else if let Some(u) = parent.and_then(ast::UseTreeList::cast) {
             if u.use_trees().next().is_none() {
@@ -616,6 +643,45 @@ impl Removable for ast::Use {
     }
 }
 
+impl EditorRemovable for ast::Use {
+    fn remove(&self, editor: &mut SyntaxEditor) {
+        let make = SyntaxFactory::new();
+
+        let next_ws = self
+            .syntax()
+            .next_sibling_or_token()
+            .and_then(|it| it.into_token())
+            .and_then(ast::Whitespace::cast);
+        if let Some(next_ws) = next_ws {
+            let ws_text = next_ws.syntax().text();
+            if let Some(rest) = ws_text.strip_prefix('\n') {
+                if rest.is_empty() {
+                    editor.delete(next_ws.syntax());
+                } else {
+                    editor.replace(next_ws.syntax(), make.whitespace(rest));
+                }
+            }
+        }
+        let prev_ws = self
+            .syntax()
+            .prev_sibling_or_token()
+            .and_then(|it| it.into_token())
+            .and_then(ast::Whitespace::cast);
+        if let Some(prev_ws) = prev_ws {
+            let ws_text = prev_ws.syntax().text();
+            let prev_newline = ws_text.rfind('\n').map(|x| x + 1).unwrap_or(0);
+            let rest = &ws_text[0..prev_newline];
+            if rest.is_empty() {
+                editor.delete(prev_ws.syntax());
+            } else {
+                editor.replace(prev_ws.syntax(), make.whitespace(rest));
+            }
+        }
+
+        editor.delete(self.syntax());
+    }
+}
+
 impl ast::Impl {
     pub fn get_or_create_assoc_item_list(&self) -> ast::AssocItemList {
         if self.assoc_item_list().is_none() {

crates/syntax/src/ast/syntax_factory/constructors.rs

@@ -4,7 +4,7 @@ use itertools::Itertools;
 use crate::{
     ast::{self, make, HasName},
     syntax_editor::SyntaxMappingBuilder,
-    AstNode,
+    AstNode, SyntaxToken,
 };
 
 use super::SyntaxFactory;
@@ -14,6 +14,10 @@ impl SyntaxFactory {
         make::name(name).clone_for_update()
     }
 
+    pub fn whitespace(&self, text: &str) -> SyntaxToken {
+        make::tokens::whitespace(text)
+    }
+
     pub fn ident_pat(&self, ref_: bool, mut_: bool, name: ast::Name) -> ast::IdentPat {
         let ast = make::ident_pat(ref_, mut_, name.clone()).clone_for_update();