Support "register" tools in module loader

packages/core/integration-tests/package.json

@@ -29,6 +29,7 @@
     "cross-env": "^7.0.0",
     "elm": "^0.19.1-5",
     "elm-hot": "^1.1.5",
+    "esbuild-register": "^3.5.0",
     "exif-reader": "^1.0.3",
     "get-port": "^5.0.0",
     "graphql": "^15.0.0",

packages/core/integration-tests/test/registered-plugins.js

@@ -0,0 +1,69 @@
+// @flow strict-local
+import assert from 'assert';
+import path from 'path';
+import {bundle, run, overlayFS, fsFixture} from '@parcel/test-utils';
+
+describe('plugins with "registered" languages', () => {
+  it('should support plugins with esbuild-register', async () => {
+    const dir = path.join(__dirname, 'esbuild-register-plugin');
+    overlayFS.mkdirp(dir);
+
+    await fsFixture(overlayFS, dir)`
+      package.json:
+        {
+          "name": "app",
+          "sideEffects": true
+        }
+
+      yarn.lock:
+
+      index.js:
+        console.log("Hi, mum!");
+
+      .parcelrc:
+        {
+          extends: "@parcel/config-default",
+          reporters: ["...", "./reporter-plugin.js"],
+        }
+
+      reporter-plugin.js:
+        require('esbuild-register/dist/node').register();
+        const plugin = require('./reporter-plugin.ts');
+        module.exports = plugin;
+
+      reporter-plugin.ts:
+        import fs from 'fs';
+        import { Reporter } from '@parcel/plugin';
+        import { someString } from './some-string';
+        export default new Reporter({
+            async report({ event, options }) {
+                if (event.type === 'buildStart') {
+                    await options.outputFS.writeFile(options.projectRoot + '/output.txt', 'Hello! ' + someString, 'utf8');
+                }
+            }
+        });
+
+      some-string.ts:
+        export const someString = 'something';
+        `;
+
+    const b = await bundle(path.join(dir, 'index.js'), {
+      inputFS: overlayFS,
+      outputFS: overlayFS,
+      additionalReporters: [
+        {packageName: '@parcel/reporter-json', resolveFrom: __filename},
+      ],
+    });
+
+    await run(b);
+
+    // Tests that the plugin actually loaded properly by validating that it output
+    // what it was supposed to output. If `esbuild-register` isn't used, or the resolver
+    // doesn't support updating extensions as they change, then the plugin won't work.
+    assert(overlayFS.existsSync(path.join(dir, 'output.txt')));
+    assert.equal(
+      overlayFS.readFileSync(path.join(dir, 'output.txt'), 'utf8'),
+      'Hello! something',
+    );
+  });
+});

packages/core/package-manager/src/NodePackageManager.js

@@ -58,6 +58,7 @@ export class NodePackageManager implements PackageManager {
   projectRoot: FilePath;
   installer: ?PackageInstaller;
   resolver: ResolverBase;
+  currentExtensions: Array<string>;
 
   constructor(
     fs: FileSystem,
@@ -67,6 +68,11 @@ export class NodePackageManager implements PackageManager {
     this.fs = fs;
     this.projectRoot = projectRoot;
     this.installer = installer;
+
+    // $FlowFixMe - no type for _extensions
+    this.currentExtensions = Object.keys(Module._extensions).map(e =>
+      e.substring(1),
+    );
   }
 
   _createResolver(): ResolverBase {
@@ -96,6 +102,7 @@ export class NodePackageManager implements PackageManager {
               );
             }
           : undefined,
+      extensions: this.currentExtensions,
     });
   }
 
@@ -170,6 +177,17 @@ export class NodePackageManager implements PackageManager {
 
     // $FlowFixMe
     let m = new Module(filePath, Module._cache[from] || module.parent);
+
+    // $FlowFixMe _extensions not in type
+    const extensions = Object.keys(Module._extensions);
+    // This handles supported extensions changing due to, for example, esbuild/register being used
+    // We assume that the extension list will change in size - as these tools usually add support for
+    // additional extensions.
+    if (extensions.length !== this.currentExtensions.length) {
+      this.currentExtensions = extensions.map(e => e.substring(1));
+      this.resolver = this._createResolver();
+    }
+
     // $FlowFixMe[prop-missing]
     Module._cache[filePath] = m;
 

yarn.lock

@@ -4955,6 +4955,13 @@ debug@^3.1.0, debug@^3.2.6, debug@^3.2.7:
   dependencies:
     ms "^2.1.1"
 
+debug@^4.3.4:
+  version "4.3.4"
+  resolved "https://packages.atlassian.com/api/npm/npm-remote/debug/-/debug-4.3.4.tgz#1319f6579357f2338d3337d2cdd4914bb5dcc865"
+  integrity sha512-PRWFHuSU3eDtQJPvnNY7Jcket1j0t5OuOsFzPPzsekD52Zl8qUfFIPEiswXqIvHWGVHOgX+7G/vCNNhehwxfkQ==
+  dependencies:
+    ms "2.1.2"
+
 debuglog@^1.0.1:
   version "1.0.1"
   resolved "https://registry.yarnpkg.com/debuglog/-/debuglog-1.0.1.tgz#aa24ffb9ac3df9a2351837cfb2d279360cd78492"
@@ -5662,6 +5669,13 @@ esbuild-openbsd-64@0.13.12:
   resolved "https://registry.yarnpkg.com/esbuild-openbsd-64/-/esbuild-openbsd-64-0.13.12.tgz#adde32f2f1b05dc4bd4fc544d6ea5a4379f9ca4d"
   integrity sha512-KuLCmYMb2kh05QuPJ+va60bKIH5wHL8ypDkmpy47lzwmdxNsuySeCMHuTv5o2Af1RUn5KLO5ZxaZeq4GEY7DaQ==
 
+esbuild-register@^3.5.0:
+  version "3.5.0"
+  resolved "https://packages.atlassian.com/api/npm/npm-remote/esbuild-register/-/esbuild-register-3.5.0.tgz#449613fb29ab94325c722f560f800dd946dc8ea8"
+  integrity sha512-+4G/XmakeBAsvJuDugJvtyF1x+XJT4FMocynNpxrvEBViirpfUn2PgNpCHedfWhF4WokNsO/OvMKrmJOIJsI5A==
+  dependencies:
+    debug "^4.3.4"
+
 esbuild-sunos-64@0.13.12:
   version "0.13.12"
   resolved "https://registry.yarnpkg.com/esbuild-sunos-64/-/esbuild-sunos-64-0.13.12.tgz#a7ecaf52b7364fbee76dc8aa707fa3e1cff3342c"