refactor: generate types with typescript instead of webpack/tooling

.changeset/generate-types-with-typescript.md

@@ -0,0 +1,5 @@
+---
+"enhanced-resolve": minor
+---
+
+Generate the published type declarations with TypeScript instead of `webpack/tooling`, which is no longer a dependency. Every name the package exported before is still exported, and `types.d.ts` is still the entry point, but the declarations themselves now live in `types/` and are emitted by `tsc` from the JSDoc in `lib/`. Two shapes follow the sources more closely than the previous generator did: the object form of `Plugin` no longer declares `this: Resolver` on `apply` (it is called as `plugin.apply(resolver)`, so `this` is the plugin), and the entries of `ResolveContext.stack` declare `name: string | undefined` rather than an optional `name`. Class fields that the old generator dropped, such as the cache backends on `CachedInputFileSystem`, are now part of the declarations.

.github/workflows/test.yml

@@ -36,6 +36,21 @@ jobs:
       - run: npm ci
 
       - run: npm run lint
+
+      - name: Build types
+        run: npm run build:types
+
+      # `types/` is generated from the JSDoc in `lib/`, so a checkout whose
+      # declarations were never regenerated ships types that do not describe
+      # the code. Regenerating above and diffing here is what catches that.
+      - name: Check types
+        run: |
+          if [ -n "$(git status types --porcelain)" ]; then
+            git status types --porcelain
+            echo "::error::Generated types are out of date - run 'npm run build:types' and commit the result"
+            exit 1
+          fi
+          echo "All types are up to date"
   test:
     strategy:
       fail-fast: false

.prettierignore

@@ -2,6 +2,3 @@ package.json
 package-lock.json
 test/**/*.*
 !test/*.js
-
-# Generated files
-types.d.ts

eslint.config.mjs

@@ -2,7 +2,7 @@ import { defineConfig, globalIgnores } from "eslint/config";
 import config from "eslint-config-webpack";
 
 export default defineConfig([
-	globalIgnores(["benchmark/**/fixture/**"]),
+	globalIgnores(["benchmark/**/fixture/**", "types/**"]),
 	{
 		extends: [config],
 	},

lib/PackageMapPlugin.js

@@ -20,7 +20,7 @@ const {
 
 /**
  * @typedef {object} PackageMapOptions
- * @property {string | null} configFile absolute path of the configuration file, read lazily when `packages` is not given
+ * @property {string} configFile absolute path of the configuration file, read lazily when `packages` is not given
  * @property {PackageMapPackages | null} packages an already-parsed `packages` object, used instead of reading `configFile`
  */
 
@@ -159,7 +159,7 @@ module.exports = class PackageMapPlugin {
 	 * @returns {void}
 	 */
 	_resolveConfigFile(resolver, callback) {
-		const { configFile } = /** @type {{ configFile: string }} */ (this.options);
+		const { configFile } = this.options;
 		const { realpath } = resolver.fileSystem;
 
 		if (!this.symlinks || !realpath) return callback(configFile);

lib/index.js

@@ -7,7 +7,10 @@
 
 const memoize = require("./util/memoize");
 
+/** @typedef {import("./CachedInputFileSystem")} CachedInputFileSystem */
 /** @typedef {import("./CachedInputFileSystem").BaseFileSystem} BaseFileSystem */
+/** @typedef {import("./CloneBasenamePlugin")} CloneBasenamePlugin */
+/** @typedef {import("./LogInfoPlugin")} LogInfoPlugin */
 /** @typedef {import("./PnpPlugin").PnpApiImpl} PnpApi */
 /** @typedef {import("./Resolver")} Resolver */
 /** @typedef {import("./Resolver").Context} Context */
@@ -18,6 +21,7 @@ const memoize = require("./util/memoize");
 /** @typedef {import("./Resolver").SyncFileSystem} SyncFileSystem */
 /** @typedef {import("./ResolverFactory").Plugin} Plugin */
 /** @typedef {import("./ResolverFactory").UserResolveOptions} ResolveOptions */
+/** @typedef {import("./TsconfigPathsPlugin")} TsconfigPathsPlugin */
 
 /**
  * @typedef {{

lib/util/graceful-fs-browser.js

@@ -16,9 +16,13 @@ const message =
 	"Pass a `fileSystem` to `create()` or `ResolverFactory.createResolver()`.";
 
 /**
+ * Takes the arguments its callers pass - `readFile(path, callback)` and the
+ * rest - so the declaration describes a call that actually compiles, even
+ * though every one of them throws.
+ * @param {...unknown} _args arguments, ignored
  * @returns {never} always throws
  */
-const unavailable = () => {
+const unavailable = (..._args) => {
 	throw new Error(message);
 };