Supports rules that are written as ECMAScript Modules

[azu]

Currently, textlint can not load a rule that is ECMAScript Modules(ESM).

It means that textlint-module-loader.ts use Dynamic Import instead of require to load a rule module.

This issue aim to support to load a rule that is written by ESM.
It is not that rewrite textlint to ESM.

• Current: require() in CJS can not load ESM, It only load CJS
• Next(This issue): import() in CJS can load ESM and CJS

TODO

• How to treat export default { linter, fixter }?
  • import(rule) → .default.default issue still exists?
  • feat(config-loader): support a rule written by ESM secretlint/secretlint#187
  • Adding an option to interpret __esModule as Babel does · Issue #40891 · nodejs/node
  • feat(compartment-mapper): full support of __esModule endojs/endo#1149
  • Should we still use default export? (named export does not cause this issue)
• Update to TypeScript 4.7
  • require TS 4.7 to use import() in CJS.
  • Use native dynamic import() · Issue #197 · secretlint/secretlint

[azu]

1. Refactor Config
   • Inject config into TextlintEngine from outside like constructor DI
   • Or. No use class. instaed of it, use async function
     • constructor does not support async
   • It means that we need to make config loading async

     • textlint/packages/textlint/src/config/config.ts

       Line 388 in d4c5075

       const presetRulesConfig = loadRulesConfigFromPresets(this.presets, moduleResolver);

   • Probably, we need to based on https://github.com/textlint/editor/tree/master/packages/%40textlint/config-loader
2. use dynamic import for loading rule/plugin

[azu]

Change to Async:

• Config Loading
  • textlintrc.mjs supports require Async API: feat: Support loading ES Modules cosmiconfig/cosmiconfig#283
• Rule/Preset/Filter/Plugin Loading
  • Need to use Dynamic Import to load a module written in ESM

flowchart LR
   A[Load Config File] --> B[Load Modules]

Loading

[azu]

We will introduce new API like createTextlint for supporting Async APIs.
v13 continue to support current TextLintEngine and TextFixEngine for backward compatible.

• textlint v13 roadmap #902

New createTextlint support ESM rules/plugins.
In other hands, TextLintEngine and TextFixEngine can not support ESM rules/plugins.

https://github.com/textlint/textlint/blob/60cea514f7eaefbff4411087d16a51daf68f12a4/packages/textlint/src/index.ts

API	Description	Behavior	Target Platform	Current Status	Next Status
cli	Command LIne Interface	Async	Node.js	✅	✅ (Use createTextlint internally)
textlint	TextLintCore alias	Async	Node.js/CommonJS	❌ Deprecated	❌ Deprecated
TextLintCore	Old API. It is Procedural API. Lint Only Single File. Recommended to use @texltint/kernel module instead of It.	Async	Node.js/CommonJS	❌ Deprecated	❌ Deprecated
TextLintEngine	Lint Engine API. It load .textlintrc automaticaly	◉ Loading is Sync ◉ Linting is Async	Node.js/CommonJS	✅ Recommended	❌ Deprecated
TextFixEngine	Fix Engine API. It load .textlintrc automaticaly	◉ Loading is Sync ◉ Fixing is Async	Node.js/CommonJS	✅ Recommended	❌ Deprecated
createLinter	Combine TextLintEngine and TextFixEngine. Support Async APIs.	◉ Loading is Async ◉ Linting/Fixing is Async	Node.js/CommonJS and ESM	None	✅ Recommended

[azu]

We have two config

• .textlintrc config file
• CLI options - It override textlintrc

It is just idea that we can implement these as separated loader and merge these.

type Loader = (_:unknown) => Promise<Config>;
const config = mergeConfig({
 await configFileLoader(),
 await cliLoader()
});

createTextlint({
  config
});

// OR
createTextlint({
  loaders: [configFileLoader(), cliLoader()]
});