Add alt-s to helix mode (#33918)

Closes #31562

Release Notes:

- Helix: bind alt-s to SplitSelectionIntoLines

---------

Co-authored-by: Ben Kunkle <ben@zed.dev>

assets/keymaps/vim.json

@@ -407,6 +407,7 @@
       "g w": "vim::PushRewrap",
       "insert": "vim::InsertBefore",
       "alt-.": "vim::RepeatFind",
+      "alt-s": ["editor::SplitSelectionIntoLines", { "keep_selections": true }],
       // tree-sitter related commands
       "[ x": "editor::SelectLargerSyntaxNode",
       "] x": "editor::SelectSmallerSyntaxNode",

crates/editor/src/actions.rs

@@ -273,6 +273,16 @@ pub enum UuidVersion {
     V7,
 }
 
+/// Splits selection into individual lines.
+#[derive(PartialEq, Clone, Deserialize, Default, JsonSchema, Action)]
+#[action(namespace = editor)]
+#[serde(deny_unknown_fields)]
+pub struct SplitSelectionIntoLines {
+    /// Keep the text selected after splitting instead of collapsing to cursors.
+    #[serde(default)]
+    pub keep_selections: bool,
+}
+
 /// Goes to the next diagnostic in the file.
 #[derive(PartialEq, Clone, Default, Debug, Deserialize, JsonSchema, Action)]
 #[action(namespace = editor)]
@@ -672,8 +682,6 @@ actions!(
         SortLinesCaseInsensitive,
         /// Sorts selected lines case-sensitively.
         SortLinesCaseSensitive,
-        /// Splits selection into individual lines.
-        SplitSelectionIntoLines,
         /// Stops the language server for the current file.
         StopLanguageServer,
         /// Switches between source and header files.

crates/editor/src/editor.rs

@@ -13612,7 +13612,7 @@ impl Editor {
 
     pub fn split_selection_into_lines(
         &mut self,
-        _: &SplitSelectionIntoLines,
+        action: &SplitSelectionIntoLines,
         window: &mut Window,
         cx: &mut Context<Self>,
     ) {
@@ -13629,8 +13629,21 @@ impl Editor {
             let buffer = self.buffer.read(cx).read(cx);
             for selection in selections {
                 for row in selection.start.row..selection.end.row {
-                    let cursor = Point::new(row, buffer.line_len(MultiBufferRow(row)));
-                    new_selection_ranges.push(cursor..cursor);
+                    let line_start = Point::new(row, 0);
+                    let line_end = Point::new(row, buffer.line_len(MultiBufferRow(row)));
+
+                    if action.keep_selections {
+                        // Keep the selection range for each line
+                        let selection_start = if row == selection.start.row {
+                            selection.start
+                        } else {
+                            line_start
+                        };
+                        new_selection_ranges.push(selection_start..line_end);
+                    } else {
+                        // Collapse to cursor at end of line
+                        new_selection_ranges.push(line_end..line_end);
+                    }
                 }
 
                 let is_multiline_selection = selection.start.row != selection.end.row;
@@ -13638,7 +13651,16 @@ impl Editor {
                 // so this action feels more ergonomic when paired with other selection operations
                 let should_skip_last = is_multiline_selection && selection.end.column == 0;
                 if !should_skip_last {
-                    new_selection_ranges.push(selection.end..selection.end);
+                    if action.keep_selections {
+                        if is_multiline_selection {
+                            let line_start = Point::new(selection.end.row, 0);
+                            new_selection_ranges.push(line_start..selection.end);
+                        } else {
+                            new_selection_ranges.push(selection.start..selection.end);
+                        }
+                    } else {
+                        new_selection_ranges.push(selection.end..selection.end);
+                    }
                 }
             }
         }

crates/editor/src/editor_tests.rs

@@ -6401,7 +6401,7 @@ async fn test_split_selection_into_lines(cx: &mut TestAppContext) {
     fn test(cx: &mut EditorTestContext, initial_state: &'static str, expected_state: &'static str) {
         cx.set_state(initial_state);
         cx.update_editor(|e, window, cx| {
-            e.split_selection_into_lines(&SplitSelectionIntoLines, window, cx)
+            e.split_selection_into_lines(&Default::default(), window, cx)
         });
         cx.assert_editor_state(expected_state);
     }
@@ -6489,7 +6489,7 @@ async fn test_split_selection_into_lines_interacting_with_creases(cx: &mut TestA
                 DisplayPoint::new(DisplayRow(4), 4)..DisplayPoint::new(DisplayRow(4), 4),
             ])
         });
-        editor.split_selection_into_lines(&SplitSelectionIntoLines, window, cx);
+        editor.split_selection_into_lines(&Default::default(), window, cx);
         assert_eq!(
             editor.display_text(cx),
             "aaaaa\nbbbbb\nccc⋯eeee\nfffff\nggggg\n⋯i"
@@ -6505,7 +6505,7 @@ async fn test_split_selection_into_lines_interacting_with_creases(cx: &mut TestA
                 DisplayPoint::new(DisplayRow(5), 0)..DisplayPoint::new(DisplayRow(0), 1)
             ])
         });
-        editor.split_selection_into_lines(&SplitSelectionIntoLines, window, cx);
+        editor.split_selection_into_lines(&Default::default(), window, cx);
         assert_eq!(
             editor.display_text(cx),
             "aaaaa\nbbbbb\nccccc\nddddd\neeeee\nfffff\nggggg\nhhhhh\niiiii"