Implement delete word before/after

Author: andrechen77

README.md

@@ -35,6 +35,8 @@ This [Obsidian](https://obsidian.md) plugin adds keyboard shortcuts (hotkeys) co
 | Go to line number                                | Not set                    |
 | Delete to start of line                          | Not set                    |
 | Delete to end of line                            | Not set                    |
+| Delete word before cursor                        | Not set                    |
+| Delete word after cursor                         | Not set                    |
 | Transform selection to uppercase                 | Not set                    |
 | Transform selection to lowercase                 | Not set                    |
 | Transform selection to title case                | Not set                    |

src/__tests__/actions-cursor.spec.ts

@@ -21,6 +21,7 @@ import {
   insertCursorAbove,
   insertCursorBelow,
   moveWord,
+  deleteWord,
   selectWord,
 } from '../actions';
 import { CASE, CODE_EDITOR } from '../constants';
@@ -481,6 +482,39 @@ describe('Code Editor Shortcuts: actions - single cursor selection', () => {
     });
   });
 
+  describe('deleteWord', () => {
+    // deleteWord computes the deletion range via moveWord (goWordLeft /
+    // goWordRight), so forward the mocked `exec` to the real CodeMirror
+    // command in order to verify the resulting document mutation
+    beforeEach(() => {
+      (editor.exec as jest.Mock).mockImplementation((name: string) =>
+        (editor as any).execCommand(name),
+      );
+    });
+
+    afterEach(() => {
+      (editor.exec as jest.Mock).mockReset();
+    });
+
+    it('should delete the word before the cursor', () => {
+      editor.setCursor({ line: 1, ch: 5 }); // 'dolor{cursor} sit'
+      deleteWord(editor as any, 'before');
+
+      const { doc, cursor } = getDocumentAndSelection(editor);
+      expect(doc).toEqual('lorem ipsum\n sit\namet');
+      expect(cursor).toEqual(expect.objectContaining({ line: 1, ch: 0 }));
+    });
+
+    it('should delete the word after the cursor', () => {
+      editor.setCursor({ line: 1, ch: 0 }); // '{cursor}dolor sit'
+      deleteWord(editor as any, 'after');
+
+      const { doc, cursor } = getDocumentAndSelection(editor);
+      expect(doc).toEqual('lorem ipsum\n sit\namet');
+      expect(cursor).toEqual(expect.objectContaining({ line: 1, ch: 0 }));
+    });
+  });
+
   describe('selectWord', () => {
     it('should extend the selection to the previous word, preserving the anchor', () => {
       editor.setSelections([

src/actions.ts

@@ -511,6 +511,28 @@ export const moveWord = (editor: Editor, direction: 'left' | 'right') => {
   }
 };
 
+// There is no built-in command for deleting a word (unlike goWordLeft /
+// goWordRight, delWordBefore / delWordAfter are not supported by Obsidian's
+// editor.exec), so the word boundary is instead found by moving the cursor
+// with moveWord and deleting the text passed over
+export const deleteWord = (editor: Editor, direction: 'before' | 'after') => {
+  const oldPositions = editor
+    .listSelections()
+    .map((selection) => selection.head);
+  moveWord(editor, direction === 'before' ? 'left' : 'right');
+  const newPositions = editor
+    .listSelections()
+    .map((selection) => selection.head);
+
+  const changes: EditorChange[] = oldPositions.map((oldPos, index) => {
+    const newPos = newPositions[index];
+    const [from, to] =
+      direction === 'before' ? [newPos, oldPos] : [oldPos, newPos];
+    return { from, to, text: '' };
+  });
+  editor.transaction({ changes });
+};
+
 // There is no built-in command for extending the selection by one word, so
 // the anchor of each selection is preserved across a plain word-move
 export const selectWord = (editor: Editor, direction: 'left' | 'right') => {

src/main.ts

@@ -5,6 +5,7 @@ import {
   deleteLine,
   deleteToStartOfLine,
   deleteToEndOfLine,
+  deleteWord,
   expandSelectionToBrackets,
   expandSelectionToQuotes,
   expandSelectionToQuotesOrBrackets,
@@ -102,6 +103,18 @@ export default class CodeEditorShortcuts extends Plugin {
         withMultipleSelections(editor, deleteToEndOfLine),
     });
 
+    this.addCommand({
+      id: 'deleteWordBefore',
+      name: 'Delete word before cursor',
+      editorCallback: (editor) => deleteWord(editor, 'before'),
+    });
+
+    this.addCommand({
+      id: 'deleteWordAfter',
+      name: 'Delete word after cursor',
+      editorCallback: (editor) => deleteWord(editor, 'after'),
+    });
+
     this.addCommand({
       id: 'joinLines',
       name: 'Join lines',