Spell Checker Plugin

Live spell check via the in-house Hunspell engine (@codemerge/hunspell, also bundled into on-codemerge). Dictionaries are not shipped with on-codemerge — you pass .aff / .dic URLs when creating the plugin.

Toggle: Tools → Spell Checker or Mod-Shift-s. Misspellings get a misspelled mark (red underline).

Demo

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Install dictionaries

Use Hunspell packages from wooorm/dictionaries (npm: dictionary-<locale>):

npm install dictionary-en
# optional:
npm install dictionary-ru dictionary-de dictionary-fr

Each package contains index.aff and index.dic.

Locale	Package
English	dictionary-en
Russian	dictionary-ru
German	dictionary-de
French	dictionary-fr
Spanish	dictionary-es
…	dictionary-<code> — see the repo for the full list

You can also host your own .aff / .dic files and point URLs at them.

Connect to the editor

Vite / VitePress

dictionary-en only exports index.js (uses Node fs) — do not deep-import index.aff via the package name (Vite/Node exports will fail). Point at the files with import.meta.url (or host them yourself):

import { Editor, SpellCheckerPlugin } from 'on-codemerge';
import 'on-codemerge/index.css';
import 'on-codemerge/public.css';

const enAff = new URL('../node_modules/dictionary-en/index.aff', import.meta.url).href;
const enDic = new URL('../node_modules/dictionary-en/index.dic', import.meta.url).href;
// Or: import enAff from './dicts/en.aff?url' after copying the files into your app.

const editor = new Editor(container, {
  plugins: [
    SpellCheckerPlugin({
      dictionaries: {
        en: { aff: enAff, dic: enDic },
        // ru: { aff: ruAff, dic: ruDic },
      },
      // defaultLocale: 'en', // fallback when editor locale has no entry
    }),
  ],
});

Allow asset imports in vite.config.ts / VitePress vite config if needed:

export default defineConfig({
  assetsInclude: ['**/*.aff', '**/*.dic'],
});

Static / public folder

Copy files into public/dictionaries/ and pass paths:

SpellCheckerPlugin({
  dictionaries: {
    en: {
      aff: '/dictionaries/en.aff',
      dic: '/dictionaries/en.dic',
    },
  },
});

Locale matching

The plugin uses the language part of editor.getLocale() (en-US → en). If that key is missing in dictionaries, it falls back to defaultLocale (default 'en'), then to the first configured locale.

Options

type SpellDictionaryFiles = { aff: string; dic: string };

type SpellCheckerOptions = {
  /** locale → URLs to Hunspell .aff / .dic (required) */
  dictionaries: Record<string, SpellDictionaryFiles>;
  /** fallback locale key (default: 'en') */
  defaultLocale?: string;
};

Styling

Misspelled words use the misspelled mark; public CSS paints .misspelled-word with a red underline. Override in your app if needed.

Notes

• SpellCheckerPlugin is not included in createDefaultPlugins() — configure dictionaries and add it yourself.
• Code blocks are skipped.
• Checking is debounced (~280ms) on docChanged.