feat: threads (#39)

* fix: handle exceptions from eslint

* fix: prevent ts from trying&failing to overwrite js files

* feat: use jest-worker

declarations/getESLint.d.ts

@@ -1,16 +1,28 @@
 /** @typedef {import('eslint').ESLint} ESLint */
+/** @typedef {import('eslint').ESLint.LintResult} LintResult */
 /** @typedef {import('./options').Options} Options */
+/** @typedef {() => Promise<void>} AsyncTask */
+/** @typedef {(files: string|string[]) => Promise<LintResult[]>} LintTask */
+/** @typedef {JestWorker & {lintFiles: LintTask}} Worker */
+/** @typedef {{threads: number, ESLint: ESLint, eslint: ESLint, lintFiles: LintTask, cleanup: AsyncTask}} Linter */
 /**
  * @param {Options} options
- * @returns {{ESLint: ESLint, eslint: ESLint}}
+ * @returns {Linter}
  */
-export default function getESLint(
-  options: Options
-): {
-  ESLint: import('eslint').ESLint;
-  eslint: import('eslint').ESLint;
-};
+export function loadESLint(options: Options): Linter;
+/**
+ * @param {number} poolSize
+ * @param {Options} options
+ * @returns {Linter}
+ */
+export function loadESLintThreaded(poolSize: number, options: Options): Linter;
+/**
+ * @param {Options} options
+ * @returns {Linter}
+ */
+export default function getESLint({ threads, ...options }: Options): Linter;
 export type ESLint = import('eslint').ESLint;
+export type LintResult = import('eslint').ESLint.LintResult;
 export type Options = {
   context?: string | undefined;
   emitError?: boolean | undefined;
@@ -26,4 +38,18 @@ export type Options = {
   lintDirtyModulesOnly?: boolean | undefined;
   quiet?: boolean | undefined;
   outputReport?: import('./options').OutputReport | undefined;
+  threads?: number | boolean | undefined;
+};
+export type AsyncTask = () => Promise<void>;
+export type LintTask = (files: string | string[]) => Promise<LintResult[]>;
+export type Worker = JestWorker & {
+  lintFiles: LintTask;
+};
+export type Linter = {
+  threads: number;
+  ESLint: ESLint;
+  eslint: ESLint;
+  lintFiles: LintTask;
+  cleanup: AsyncTask;
 };
+import JestWorker from 'jest-worker';

declarations/index.d.ts

@@ -37,4 +37,5 @@ export type Options = {
   lintDirtyModulesOnly?: boolean | undefined;
   quiet?: boolean | undefined;
   outputReport?: import('./options').OutputReport | undefined;
+  threads?: number | boolean | undefined;
 };

declarations/linter.d.ts

@@ -12,10 +12,12 @@
 /** @typedef {(files: string|string[]) => void} Linter */
 /**
  * @param {Options} options
+ * @param {Compilation} compilation
  * @returns {{lint: Linter, report: Reporter}}
  */
 export default function linter(
-  options: Options
+  options: Options,
+  compilation: Compilation
 ): {
   lint: Linter;
   report: Reporter;
@@ -41,6 +43,7 @@ export type Options = {
   lintDirtyModulesOnly?: boolean | undefined;
   quiet?: boolean | undefined;
   outputReport?: import('./options').OutputReport | undefined;
+  threads?: number | boolean | undefined;
 };
 export type FormatterFunction = (
   results: import('eslint').ESLint.LintResult[],

declarations/options.d.ts

@@ -28,6 +28,7 @@
  * @property {boolean=} lintDirtyModulesOnly
  * @property {boolean=} quiet
  * @property {OutputReport=} outputReport
+ * @property {number|boolean=} threads
  */
 /**
  * @param {Options} pluginOptions
@@ -65,4 +66,5 @@ export type Options = {
   lintDirtyModulesOnly?: boolean | undefined;
   quiet?: boolean | undefined;
   outputReport?: OutputReport | undefined;
+  threads?: (number | boolean) | undefined;
 };

declarations/worker.d.ts

@@ -0,0 +1,12 @@
+export type setupOptions = {
+  /**
+   * - import path of eslint
+   */
+  eslintPath?: string | undefined;
+  /**
+   * - linter options
+   */
+  eslintOptions?: ESLintOptions | undefined;
+};
+export type ESLint = import('eslint').ESLint;
+export type ESLintOptions = import('eslint').ESLint.Options;