History (Undo/Redo)

HistoryPlugin wraps ProseMirror history and registers undo/redo commands.

import {
  HistoryPlugin,
  QalmaCommand,
  QalmaToolbar,
  createQalmaEditor,
} from '@qalma/editor';

const editor = createQalmaEditor({
  plugins: [
    HistoryPlugin.configure({
      depth: 200,
      newGroupDelay: 750,
    }),
  ],
});

Commands and shortcuts

Command	Description	Shortcut
undo	Reverts the previous history event.	Mod-z
redo	Reapplies the next history event.	Shift-Mod-z, Mod-y

<qalma-toolbar label="History">
  <button type="button" qalmaCommand="undo">Undo</button>
  <button type="button" qalmaCommand="redo">Redo</button>
</qalma-toolbar>

The plugin does not expose command-state queries. QalmaCommand still disables the buttons through canExecute(), but it does not set aria-pressed.

Options

Option	Default	Validation
depth	100	Positive integer.
newGroupDelay	500	Non-negative finite number.

depth controls how many history events ProseMirror keeps. newGroupDelay controls how close transactions must be in time to be grouped together.

Programmatic usage

Use the controller when you need custom history controls.

readonly canUndo = computed(() => this.editor.canExecute('undo'));
readonly canRedo = computed(() => this.editor.canExecute('redo'));

undo(): void {
  this.editor.execute('undo');
}

redo(): void {
  this.editor.execute('redo');
}

Automatic transactions

Some plugins mark maintenance transactions outside the undo stack. For example, TrailingParagraphPlugin inserts its automatic final paragraph with addToHistory: false, so undo stays focused on user edits.