feat(ui): add missing vim mode motions (X, ~, r, f/F/t/T, df/dt and friends) (#21932)

packages/cli/src/ui/components/shared/text-buffer.ts

@@ -1703,6 +1703,25 @@ export type TextBufferAction =
   | { type: 'vim_change_to_first_nonwhitespace' }
   | { type: 'vim_delete_to_first_line'; payload: { count: number } }
   | { type: 'vim_delete_to_last_line'; payload: { count: number } }
+  | { type: 'vim_delete_char_before'; payload: { count: number } }
+  | { type: 'vim_toggle_case'; payload: { count: number } }
+  | { type: 'vim_replace_char'; payload: { char: string; count: number } }
+  | {
+      type: 'vim_find_char_forward';
+      payload: { char: string; count: number; till: boolean };
+    }
+  | {
+      type: 'vim_find_char_backward';
+      payload: { char: string; count: number; till: boolean };
+    }
+  | {
+      type: 'vim_delete_to_char_forward';
+      payload: { char: string; count: number; till: boolean };
+    }
+  | {
+      type: 'vim_delete_to_char_backward';
+      payload: { char: string; count: number; till: boolean };
+    }
   | {
       type: 'toggle_paste_expansion';
       payload: { id: string; row: number; col: number };
@@ -2484,6 +2503,13 @@ function textBufferReducerLogic(
     case 'vim_change_to_first_nonwhitespace':
     case 'vim_delete_to_first_line':
     case 'vim_delete_to_last_line':
+    case 'vim_delete_char_before':
+    case 'vim_toggle_case':
+    case 'vim_replace_char':
+    case 'vim_find_char_forward':
+    case 'vim_find_char_backward':
+    case 'vim_delete_to_char_forward':
+    case 'vim_delete_to_char_backward':
       return handleVimAction(state, action as VimAction);
 
     case 'toggle_paste_expansion': {
@@ -3043,6 +3069,58 @@ export function useTextBuffer({
     dispatch({ type: 'vim_delete_char', payload: { count } });
   }, []);
 
+  const vimDeleteCharBefore = useCallback((count: number): void => {
+    dispatch({ type: 'vim_delete_char_before', payload: { count } });
+  }, []);
+
+  const vimToggleCase = useCallback((count: number): void => {
+    dispatch({ type: 'vim_toggle_case', payload: { count } });
+  }, []);
+
+  const vimReplaceChar = useCallback((char: string, count: number): void => {
+    dispatch({ type: 'vim_replace_char', payload: { char, count } });
+  }, []);
+
+  const vimFindCharForward = useCallback(
+    (char: string, count: number, till: boolean): void => {
+      dispatch({
+        type: 'vim_find_char_forward',
+        payload: { char, count, till },
+      });
+    },
+    [],
+  );
+
+  const vimFindCharBackward = useCallback(
+    (char: string, count: number, till: boolean): void => {
+      dispatch({
+        type: 'vim_find_char_backward',
+        payload: { char, count, till },
+      });
+    },
+    [],
+  );
+
+  const vimDeleteToCharForward = useCallback(
+    (char: string, count: number, till: boolean): void => {
+      dispatch({
+        type: 'vim_delete_to_char_forward',
+        payload: { char, count, till },
+      });
+    },
+    [],
+  );
+
+  const vimDeleteToCharBackward = useCallback(
+    (char: string, count: number, till: boolean): void => {
+      dispatch({
+        type: 'vim_delete_to_char_backward',
+        payload: { char, count, till },
+      });
+    },
+    [],
+  );
+
   const vimInsertAtCursor = useCallback((): void => {
     dispatch({ type: 'vim_insert_at_cursor' });
   }, []);
@@ -3542,6 +3620,13 @@ export function useTextBuffer({
       vimMoveBigWordBackward,
       vimMoveBigWordEnd,
       vimDeleteChar,
+      vimDeleteCharBefore,
+      vimToggleCase,
+      vimReplaceChar,
+      vimFindCharForward,
+      vimFindCharBackward,
+      vimDeleteToCharForward,
+      vimDeleteToCharBackward,
       vimInsertAtCursor,
       vimAppendAtCursor,
       vimOpenLineBelow,
@@ -3630,6 +3715,13 @@ export function useTextBuffer({
       vimMoveBigWordBackward,
       vimMoveBigWordEnd,
       vimDeleteChar,
+      vimDeleteCharBefore,
+      vimToggleCase,
+      vimReplaceChar,
+      vimFindCharForward,
+      vimFindCharBackward,
+      vimDeleteToCharForward,
+      vimDeleteToCharBackward,
       vimInsertAtCursor,
       vimAppendAtCursor,
       vimOpenLineBelow,
@@ -3937,6 +4029,20 @@ export interface TextBuffer {
    * Delete N characters at cursor (vim 'x' command)
    */
   vimDeleteChar: (count: number) => void;
+  /** Delete N characters before cursor (vim 'X') */
+  vimDeleteCharBefore: (count: number) => void;
+  /** Toggle case of N characters at cursor (vim '~') */
+  vimToggleCase: (count: number) => void;
+  /** Replace N characters at cursor with char, stay in NORMAL mode (vim 'r') */
+  vimReplaceChar: (char: string, count: number) => void;
+  /** Move to Nth occurrence of char forward on line; till=true stops before it (vim 'f'/'t') */
+  vimFindCharForward: (char: string, count: number, till: boolean) => void;
+  /** Move to Nth occurrence of char backward on line; till=true stops after it (vim 'F'/'T') */
+  vimFindCharBackward: (char: string, count: number, till: boolean) => void;
+  /** Delete from cursor to Nth occurrence of char forward; till=true excludes the char (vim 'df'/'dt') */
+  vimDeleteToCharForward: (char: string, count: number, till: boolean) => void;
+  /** Delete from Nth occurrence of char backward to cursor; till=true excludes the char (vim 'dF'/'dT') */
+  vimDeleteToCharBackward: (char: string, count: number, till: boolean) => void;
   /**
    * Enter insert mode at cursor (vim 'i' command)
    */

packages/cli/src/ui/components/shared/vim-buffer-actions.test.ts

@@ -1727,4 +1727,416 @@ describe('vim-buffer-actions', () => {
       });
     });
   });
+
+  describe('Character manipulation commands (X, ~, r, f/F/t/T)', () => {
+    describe('vim_delete_char_before (X)', () => {
+      it('should delete the character before the cursor', () => {
+        const state = createTestState(['hello'], 0, 3);
+        const result = handleVimAction(state, {
+          type: 'vim_delete_char_before' as const,
+          payload: { count: 1 },
+        });
+        expect(result.lines[0]).toBe('helo');
+        expect(result.cursorCol).toBe(2);
+      });
+
+      it('should delete N characters before the cursor', () => {
+        const state = createTestState(['hello world'], 0, 5);
+        const result = handleVimAction(state, {
+          type: 'vim_delete_char_before' as const,
+          payload: { count: 3 },
+        });
+        expect(result.lines[0]).toBe('he world');
+        expect(result.cursorCol).toBe(2);
+      });
+
+      it('should clamp to start of line when count exceeds position', () => {
+        const state = createTestState(['hello'], 0, 2);
+        const result = handleVimAction(state, {
+          type: 'vim_delete_char_before' as const,
+          payload: { count: 10 },
+        });
+        expect(result.lines[0]).toBe('llo');
+        expect(result.cursorCol).toBe(0);
+      });
+
+      it('should do nothing when cursor is at column 0', () => {
+        const state = createTestState(['hello'], 0, 0);
+        const result = handleVimAction(state, {
+          type: 'vim_delete_char_before' as const,
+          payload: { count: 1 },
+        });
+        expect(result.lines[0]).toBe('hello');
+        expect(result.cursorCol).toBe(0);
+      });
+
+      it('should push undo state', () => {
+        const state = createTestState(['hello'], 0, 3);
+        const result = handleVimAction(state, {
+          type: 'vim_delete_char_before' as const,
+          payload: { count: 1 },
+        });
+        expect(result.undoStack.length).toBeGreaterThan(0);
+      });
+    });
+
+    describe('vim_toggle_case (~)', () => {
+      it('should toggle lowercase to uppercase', () => {
+        const state = createTestState(['hello'], 0, 0);
+        const result = handleVimAction(state, {
+          type: 'vim_toggle_case' as const,
+          payload: { count: 1 },
+        });
+        expect(result.lines[0]).toBe('Hello');
+        expect(result.cursorCol).toBe(1);
+      });
+
+      it('should toggle uppercase to lowercase', () => {
+        const state = createTestState(['HELLO'], 0, 0);
+        const result = handleVimAction(state, {
+          type: 'vim_toggle_case' as const,
+          payload: { count: 1 },
+        });
+        expect(result.lines[0]).toBe('hELLO');
+        expect(result.cursorCol).toBe(1);
+      });
+
+      it('should toggle N characters', () => {
+        const state = createTestState(['hello world'], 0, 0);
+        const result = handleVimAction(state, {
+          type: 'vim_toggle_case' as const,
+          payload: { count: 5 },
+        });
+        expect(result.lines[0]).toBe('HELLO world');
+        expect(result.cursorCol).toBe(5); // cursor advances past the toggled range
+      });
+
+      it('should clamp count to end of line', () => {
+        const state = createTestState(['hi'], 0, 1);
+        const result = handleVimAction(state, {
+          type: 'vim_toggle_case' as const,
+          payload: { count: 100 },
+        });
+        expect(result.lines[0]).toBe('hI');
+        expect(result.cursorCol).toBe(1);
+      });
+
+      it('should do nothing when cursor is past end of line', () => {
+        const state = createTestState(['hi'], 0, 5);
+        const result = handleVimAction(state, {
+          type: 'vim_toggle_case' as const,
+          payload: { count: 1 },
+        });
+        expect(result.lines[0]).toBe('hi');
+      });
+
+      it('should push undo state', () => {
+        const state = createTestState(['hello'], 0, 0);
+        const result = handleVimAction(state, {
+          type: 'vim_toggle_case' as const,
+          payload: { count: 1 },
+        });
+        expect(result.undoStack.length).toBeGreaterThan(0);
+      });
+    });
+
+    describe('vim_replace_char (r)', () => {
+      it('should replace the character under the cursor', () => {
+        const state = createTestState(['hello'], 0, 1);
+        const result = handleVimAction(state, {
+          type: 'vim_replace_char' as const,
+          payload: { char: 'a', count: 1 },
+        });
+        expect(result.lines[0]).toBe('hallo');
+        expect(result.cursorCol).toBe(1);
+      });
+
+      it('should replace N characters with the given char', () => {
+        const state = createTestState(['hello'], 0, 1);
+        const result = handleVimAction(state, {
+          type: 'vim_replace_char' as const,
+          payload: { char: 'x', count: 3 },
+        });
+        expect(result.lines[0]).toBe('hxxxo');
+        expect(result.cursorCol).toBe(3); // cursor at last replaced char
+      });
+
+      it('should clamp replace count to end of line', () => {
+        const state = createTestState(['hi'], 0, 1);
+        const result = handleVimAction(state, {
+          type: 'vim_replace_char' as const,
+          payload: { char: 'z', count: 100 },
+        });
+        expect(result.lines[0]).toBe('hz');
+        expect(result.cursorCol).toBe(1);
+      });
+
+      it('should do nothing when cursor is past end of line', () => {
+        const state = createTestState(['hi'], 0, 5);
+        const result = handleVimAction(state, {
+          type: 'vim_replace_char' as const,
+          payload: { char: 'z', count: 1 },
+        });
+        expect(result.lines[0]).toBe('hi');
+      });
+
+      it('should push undo state', () => {
+        const state = createTestState(['hello'], 0, 0);
+        const result = handleVimAction(state, {
+          type: 'vim_replace_char' as const,
+          payload: { char: 'x', count: 1 },
+        });
+        expect(result.undoStack.length).toBeGreaterThan(0);
+      });
+    });
+
+    type FindActionCase = {
+      label: string;
+      type: 'vim_find_char_forward' | 'vim_find_char_backward';
+      cursorStart: number;
+      char: string;
+      count: number;
+      till: boolean;
+      expectedCol: number;
+    };
+    it.each<FindActionCase>([
+      {
+        label: 'f: move to char',
+        type: 'vim_find_char_forward',
+        cursorStart: 0,
+        char: 'o',
+        count: 1,
+        till: false,
+        expectedCol: 4,
+      },
+      {
+        label: 'f: Nth occurrence',
+        type: 'vim_find_char_forward',
+        cursorStart: 0,
+        char: 'o',
+        count: 2,
+        till: false,
+        expectedCol: 7,
+      },
+      {
+        label: 't: move before char',
+        type: 'vim_find_char_forward',
+        cursorStart: 0,
+        char: 'o',
+        count: 1,
+        till: true,
+        expectedCol: 3,
+      },
+      {
+        label: 'f: not found',
+        type: 'vim_find_char_forward',
+        cursorStart: 0,
+        char: 'z',
+        count: 1,
+        till: false,
+        expectedCol: 0,
+      },
+      {
+        label: 'f: skip char at cursor',
+        type: 'vim_find_char_forward',
+        cursorStart: 1,
+        char: 'h',
+        count: 1,
+        till: false,
+        expectedCol: 1,
+      },
+      {
+        label: 'F: move to char',
+        type: 'vim_find_char_backward',
+        cursorStart: 10,
+        char: 'o',
+        count: 1,
+        till: false,
+        expectedCol: 7,
+      },
+      {
+        label: 'F: Nth occurrence',
+        type: 'vim_find_char_backward',
+        cursorStart: 10,
+        char: 'o',
+        count: 2,
+        till: false,
+        expectedCol: 4,
+      },
+      {
+        label: 'T: move after char',
+        type: 'vim_find_char_backward',
+        cursorStart: 10,
+        char: 'o',
+        count: 1,
+        till: true,
+        expectedCol: 8,
+      },
+      {
+        label: 'F: not found',
+        type: 'vim_find_char_backward',
+        cursorStart: 4,
+        char: 'z',
+        count: 1,
+        till: false,
+        expectedCol: 4,
+      },
+      {
+        label: 'F: skip char at cursor',
+        type: 'vim_find_char_backward',
+        cursorStart: 3,
+        char: 'o',
+        count: 1,
+        till: false,
+        expectedCol: 3,
+      },
+    ])('$label', ({ type, cursorStart, char, count, till, expectedCol }) => {
+      const line =
+        type === 'vim_find_char_forward' ? ['hello world'] : ['hello world'];
+      const state = createTestState(line, 0, cursorStart);
+      const result = handleVimAction(state, {
+        type,
+        payload: { char, count, till },
+      });
+      expect(result.cursorCol).toBe(expectedCol);
+    });
+  });
+
+  describe('Unicode character support in find operations', () => {
+    it('vim_find_char_forward: finds multi-byte char (é) correctly', () => {
+      const state = createTestState(['café world'], 0, 0);
+      const result = handleVimAction(state, {
+        type: 'vim_find_char_forward' as const,
+        payload: { char: 'é', count: 1, till: false },
+      });
+      expect(result.cursorCol).toBe(3); // 'c','a','f','é' — é is at index 3
+      expect(result.lines[0]).toBe('café world');
+    });
+
+    it('vim_find_char_backward: finds multi-byte char (é) correctly', () => {
+      const state = createTestState(['café world'], 0, 9);
+      const result = handleVimAction(state, {
+        type: 'vim_find_char_backward' as const,
+        payload: { char: 'é', count: 1, till: false },
+      });
+      expect(result.cursorCol).toBe(3);
+    });
+
+    it('vim_delete_to_char_forward: handles multi-byte target char', () => {
+      const state = createTestState(['café world'], 0, 0);
+      const result = handleVimAction(state, {
+        type: 'vim_delete_to_char_forward' as const,
+        payload: { char: 'é', count: 1, till: false },
+      });
+      // Deletes 'caf' + 'é' → ' world' remains
+      expect(result.lines[0]).toBe(' world');
+      expect(result.cursorCol).toBe(0);
+    });
+
+    it('vim_delete_to_char_forward (till): stops before multi-byte char', () => {
+      const state = createTestState(['café world'], 0, 0);
+      const result = handleVimAction(state, {
+        type: 'vim_delete_to_char_forward' as const,
+        payload: { char: 'é', count: 1, till: true },
+      });
+      // Deletes 'caf', keeps 'é world'
+      expect(result.lines[0]).toBe('é world');
+      expect(result.cursorCol).toBe(0);
+    });
+  });
+
+  describe('vim_delete_to_char_forward (df/dt)', () => {
+    it('df: deletes from cursor through found char (inclusive)', () => {
+      const state = createTestState(['hello world'], 0, 0);
+      const result = handleVimAction(state, {
+        type: 'vim_delete_to_char_forward' as const,
+        payload: { char: 'o', count: 1, till: false },
+      });
+      expect(result.lines[0]).toBe(' world');
+      expect(result.cursorCol).toBe(0);
+    });
+
+    it('dt: deletes from cursor up to (not including) found char', () => {
+      const state = createTestState(['hello world'], 0, 0);
+      const result = handleVimAction(state, {
+        type: 'vim_delete_to_char_forward' as const,
+        payload: { char: 'o', count: 1, till: true },
+      });
+      expect(result.lines[0]).toBe('o world');
+      expect(result.cursorCol).toBe(0);
+    });
+
+    it('df with count: deletes to Nth occurrence', () => {
+      const state = createTestState(['hello world'], 0, 0);
+      const result = handleVimAction(state, {
+        type: 'vim_delete_to_char_forward' as const,
+        payload: { char: 'o', count: 2, till: false },
+      });
+      expect(result.lines[0]).toBe('rld');
+      expect(result.cursorCol).toBe(0);
+    });
+
+    it('does nothing if char not found', () => {
+      const state = createTestState(['hello'], 0, 0);
+      const result = handleVimAction(state, {
+        type: 'vim_delete_to_char_forward' as const,
+        payload: { char: 'z', count: 1, till: false },
+      });
+      expect(result.lines[0]).toBe('hello');
+      expect(result.cursorCol).toBe(0);
+    });
+
+    it('pushes undo state', () => {
+      const state = createTestState(['hello world'], 0, 0);
+      const result = handleVimAction(state, {
+        type: 'vim_delete_to_char_forward' as const,
+        payload: { char: 'o', count: 1, till: false },
+      });
+      expect(result.undoStack.length).toBeGreaterThan(0);
+    });
+  });
+
+  describe('vim_delete_to_char_backward (dF/dT)', () => {
+    it('dF: deletes from found char through cursor (inclusive)', () => {
+      const state = createTestState(['hello world'], 0, 7);
+      const result = handleVimAction(state, {
+        type: 'vim_delete_to_char_backward' as const,
+        payload: { char: 'o', count: 1, till: false },
+      });
+      // cursor at 7 ('o' in world), dFo finds 'o' at col 4
+      // delete [4, 8) — both ends inclusive → 'hell' + 'rld'
+      expect(result.lines[0]).toBe('hellrld');
+      expect(result.cursorCol).toBe(4);
+    });
+
+    it('dT: deletes from found+1 through cursor (inclusive)', () => {
+      const state = createTestState(['hello world'], 0, 7);
+      const result = handleVimAction(state, {
+        type: 'vim_delete_to_char_backward' as const,
+        payload: { char: 'o', count: 1, till: true },
+      });
+      // dTo finds 'o' at col 4, deletes [5, 8) → 'hello' + 'rld'
+      expect(result.lines[0]).toBe('hellorld');
+      expect(result.cursorCol).toBe(5);
+    });
+
+    it('does nothing if char not found', () => {
+      const state = createTestState(['hello'], 0, 4);
+      const result = handleVimAction(state, {
+        type: 'vim_delete_to_char_backward' as const,
+        payload: { char: 'z', count: 1, till: false },
+      });
+      expect(result.lines[0]).toBe('hello');
+      expect(result.cursorCol).toBe(4);
+    });
+
+    it('pushes undo state', () => {
+      const state = createTestState(['hello world'], 0, 7);
+      const result = handleVimAction(state, {
+        type: 'vim_delete_to_char_backward' as const,
+        payload: { char: 'o', count: 1, till: false },
+      });
+      expect(result.undoStack.length).toBeGreaterThan(0);
+    });
+  });
 });

packages/cli/src/ui/components/shared/vim-buffer-actions.ts

@@ -24,6 +24,13 @@ import { assumeExhaustive } from '@google/gemini-cli-core';
 
 export type VimAction = Extract<
   TextBufferAction,
+  | { type: 'vim_delete_char_before' }
+  | { type: 'vim_toggle_case' }
+  | { type: 'vim_replace_char' }
+  | { type: 'vim_find_char_forward' }
+  | { type: 'vim_find_char_backward' }
+  | { type: 'vim_delete_to_char_forward' }
+  | { type: 'vim_delete_to_char_backward' }
   | { type: 'vim_delete_word_forward' }
   | { type: 'vim_delete_word_backward' }
   | { type: 'vim_delete_word_end' }
@@ -73,6 +80,35 @@ export type VimAction = Extract<
   | { type: 'vim_escape_insert_mode' }
 >;
 
+/**
+ * Find the Nth occurrence of `char` in `codePoints`, starting at `start` and
+ * stepping by `direction` (+1 forward, -1 backward). Returns the index or -1.
+ */
+function findCharInLine(
+  codePoints: string[],
+  char: string,
+  count: number,
+  start: number,
+  direction: 1 | -1,
+): number {
+  let found = -1;
+  let hits = 0;
+  for (
+    let i = start;
+    direction === 1 ? i < codePoints.length : i >= 0;
+    i += direction
+  ) {
+    if (codePoints[i] === char) {
+      hits++;
+      if (hits >= count) {
+        found = i;
+        break;
+      }
+    }
+  }
+  return found;
+}
+
 export function handleVimAction(
   state: TextBufferState,
   action: VimAction,
@@ -1183,6 +1219,151 @@ export function handleVimAction(
       };
     }
 
+    case 'vim_delete_char_before': {
+      const { count } = action.payload;
+      if (cursorCol > 0) {
+        const deleteStart = Math.max(0, cursorCol - count);
+        const nextState = detachExpandedPaste(pushUndo(state));
+        return replaceRangeInternal(
+          nextState,
+          cursorRow,
+          deleteStart,
+          cursorRow,
+          cursorCol,
+          '',
+        );
+      }
+      return state;
+    }
+
+    case 'vim_toggle_case': {
+      const { count } = action.payload;
+      const currentLine = lines[cursorRow] || '';
+      const lineLen = cpLen(currentLine);
+      if (cursorCol >= lineLen) return state;
+      const end = Math.min(cursorCol + count, lineLen);
+      const codePoints = toCodePoints(currentLine);
+      for (let i = cursorCol; i < end; i++) {
+        const ch = codePoints[i];
+        const upper = ch.toUpperCase();
+        const lower = ch.toLowerCase();
+        codePoints[i] = ch === upper ? lower : upper;
+      }
+      const newLine = codePoints.join('');
+      const nextState = detachExpandedPaste(pushUndo(state));
+      const newLines = [...nextState.lines];
+      newLines[cursorRow] = newLine;
+      const newCol = Math.min(end, lineLen > 0 ? lineLen - 1 : 0);
+      return {
+        ...nextState,
+        lines: newLines,
+        cursorCol: newCol,
+        preferredCol: null,
+      };
+    }
+
+    case 'vim_replace_char': {
+      const { char, count } = action.payload;
+      const currentLine = lines[cursorRow] || '';
+      const lineLen = cpLen(currentLine);
+      if (cursorCol >= lineLen) return state;
+      const replaceCount = Math.min(count, lineLen - cursorCol);
+      const replacement = char.repeat(replaceCount);
+      const nextState = detachExpandedPaste(pushUndo(state));
+      const resultState = replaceRangeInternal(
+        nextState,
+        cursorRow,
+        cursorCol,
+        cursorRow,
+        cursorCol + replaceCount,
+        replacement,
+      );
+      return {
+        ...resultState,
+        cursorCol: cursorCol + replaceCount - 1,
+        preferredCol: null,
+      };
+    }
+
+    case 'vim_delete_to_char_forward': {
+      const { char, count, till } = action.payload;
+      const lineCodePoints = toCodePoints(lines[cursorRow] || '');
+      const found = findCharInLine(
+        lineCodePoints,
+        char,
+        count,
+        cursorCol + 1,
+        1,
+      );
+      if (found === -1) return state;
+      const endCol = till ? found : found + 1;
+      const nextState = detachExpandedPaste(pushUndo(state));
+      return replaceRangeInternal(
+        nextState,
+        cursorRow,
+        cursorCol,
+        cursorRow,
+        endCol,
+        '',
+      );
+    }
+
+    case 'vim_delete_to_char_backward': {
+      const { char, count, till } = action.payload;
+      const lineCodePoints = toCodePoints(lines[cursorRow] || '');
+      const found = findCharInLine(
+        lineCodePoints,
+        char,
+        count,
+        cursorCol - 1,
+        -1,
+      );
+      if (found === -1) return state;
+      const startCol = till ? found + 1 : found;
+      const endCol = cursorCol + 1; // inclusive: cursor char is part of the deletion
+      if (startCol >= endCol) return state;
+      const nextState = detachExpandedPaste(pushUndo(state));
+      const resultState = replaceRangeInternal(
+        nextState,
+        cursorRow,
+        startCol,
+        cursorRow,
+        endCol,
+        '',
+      );
+      return { ...resultState, cursorCol: startCol, preferredCol: null };
+    }
+
+    case 'vim_find_char_forward': {
+      const { char, count, till } = action.payload;
+      const lineCodePoints = toCodePoints(lines[cursorRow] || '');
+      const found = findCharInLine(
+        lineCodePoints,
+        char,
+        count,
+        cursorCol + 1,
+        1,
+      );
+      if (found === -1) return state;
+      const newCol = till ? Math.max(cursorCol, found - 1) : found;
+      return { ...state, cursorCol: newCol, preferredCol: null };
+    }
+
+    case 'vim_find_char_backward': {
+      const { char, count, till } = action.payload;
+      const lineCodePoints = toCodePoints(lines[cursorRow] || '');
+      const found = findCharInLine(
+        lineCodePoints,
+        char,
+        count,
+        cursorCol - 1,
+        -1,
+      );
+      if (found === -1) return state;
+      const newCol = till ? Math.min(cursorCol, found + 1) : found;
+      return { ...state, cursorCol: newCol, preferredCol: null };
+    }
+
     default: {
       // This should never happen if TypeScript is working correctly
       assumeExhaustive(action);