add TypeScript support for Meteor Rspack plugin when typescript npm dep exists

packages/rspack/lib/constants.js

@@ -36,6 +36,7 @@ export const GLOBAL_STATE_KEYS = {
   RSPACK_REACT_INSTALLATION_CHECKED: 'rspack.rspackReactInstallationChecked',
   RSPACK_DOCTOR_INSTALLATION_CHECKED: 'rspack.rspackDoctorInstallationChecked',
   REACT_CHECKED: 'rspack.reactChecked',
+  TYPESCRIPT_CHECKED: 'rspack.typescriptChecked',
   INITIAL_ENTRYPONTS: 'meteor.initialEntrypoints',
   CLIENT_FIRST_COMPILE: 'rspack.clientFirstCompile',
   SERVER_FIRST_COMPILE: 'rspack.serverFirstCompile',

packages/rspack/lib/dependencies.js

@@ -211,3 +211,31 @@ export async function ensureRspackDoctorInstalled() {
     'Rspack Doctor'
   );
 }
+
+/**
+ * Checks if TypeScript is installed and sets global state accordingly
+ * Sets global state and environment variables based on TypeScript detection
+ * @returns {boolean} Whether TypeScript is installed
+ */
+export function checkTypescriptInstalled() {
+  // Skip if already checked
+  if (getGlobalState(GLOBAL_STATE_KEYS.TYPESCRIPT_CHECKED, false)) {
+    return;
+  }
+
+  const appDir = getMeteorAppDir();
+  // Check if TypeScript is a dependency in the project
+  const isTypescriptInstalled = checkNpmDependencyExists('typescript', { cwd: appDir });
+
+  if (isTypescriptInstalled) {
+    // Set environment variable to indicate TypeScript is enabled
+    process.env.METEOR_TYPESCRIPT_ENABLED = 'true';
+  } else {
+    process.env.METEOR_TYPESCRIPT_ENABLED = 'false';
+  }
+
+  // Mark as checked
+  setGlobalState(GLOBAL_STATE_KEYS.TYPESCRIPT_CHECKED, true);
+
+  return isTypescriptInstalled;
+}

packages/rspack/lib/processes.js

@@ -3,7 +3,7 @@
  * @description Functions for managing Rspack processes
  */
 import { checkNpmDependencyExists, getNpxCommand } from 'meteor/tools-core/lib/npm';
-import { getMeteorAppPort } from 'meteor/tools-core/lib/meteor';
+import { getMeteorAppPort, isMeteorTypescriptProject } from 'meteor/tools-core/lib/meteor';
 
 /**
  * Calculates the devServerPort based on process.env.PORT
@@ -136,11 +136,14 @@ export function getRspackEnv({ isClient, isServer, isTest: inIsTest }) {
 
   const entryKey = `${isTest && isTestModule ? 'test' : 'main'}${isClient ? 'Client' : 'Server'}`;
   const inputFilePath = isTest && isTestModule ? initialEntrypoints.testModule : initialEntrypoints[entryKey];
-  const isTypescriptEnabled = inputFilePath?.endsWith('.ts') || inputFilePath?.endsWith('.tsx');
-  const isTsxEnabled = inputFilePath?.endsWith('.tsx');
-  const isJsxEnabled = inputFilePath?.endsWith('.jsx');
+  const isTypescriptEnabled = process.env.METEOR_TYPESCRIPT_ENABLED === 'true' ||
+    inputFilePath?.endsWith('.ts') ||
+    inputFilePath?.endsWith('.tsx');
+
+  const isReactEnabled = process.env.METEOR_REACT_ENABLED === 'true';
+  const isTsxEnabled = inputFilePath?.endsWith('.tsx') || isReactEnabled;
+  const isJsxEnabled = inputFilePath?.endsWith('.jsx') || isReactEnabled;
 
-  const isReactEnabled = !!process.env.METEOR_REACT_ENABLED;
   const isBlazeEnabled = isMeteorBlazeProject();
   const isBlazeHotEnabled = isMeteorBlazeHotProject();
   const isBundleVisualizerEnabled = isMeteorBundleVisualizerProject();

packages/rspack/rspack_plugin.js

@@ -22,6 +22,7 @@ const {
 const {
   ensureRspackInstalled,
   checkReactInstalled,
+  checkTypescriptInstalled,
   ensureRspackReactInstalled,
 } = require('./lib/dependencies');
 
@@ -114,13 +115,19 @@ if (isMeteorAppRun() || isMeteorAppBuild() || isMeteorAppTest()) {
     if (hasMeteorAppConfigAutoInstallDeps()) {
       // Ensure Rspack is installed
       await ensureRspackInstalled();
+    }
 
-      // Check if Rspack React is installed
-      if (checkReactInstalled()) {
+    // Check if Rspack React is installed
+    if (checkReactInstalled()) {
+      // Auto install deps (by default enabled)
+      if (hasMeteorAppConfigAutoInstallDeps()) {
         await ensureRspackReactInstalled();
       }
     }
 
+    // Check if TypeScript is installed
+    checkTypescriptInstalled();
+
     // Ensure the Rspack build context directory exists
     ensureRspackBuildContextExists();
 

packages/tools-core/lib/meteor.js

@@ -421,6 +421,14 @@ export function isMeteorBundleVisualizerProject() {
   return getMeteorAppPackages().includes('bundle-visualizer');
 }
 
+/**
+ * Checks if the Meteor application is a Typescript project.
+ * @returns {boolean} True if the application is a Typescript project, false otherwise.
+ */
+export function isMeteorTypescriptProject() {
+  return getMeteorAppPackages().includes('typescript');
+}
+
 /**
  * Checks if the current Meteor command is 'test-packages'.
  * @returns {boolean} True if the current command is 'test-packages', false otherwise.

tools/modern-tests/apps/react-router/package.json

@@ -26,7 +26,8 @@
     "babel-loader": "^9.1.3",
     "less": "^4.4.0",
     "less-loader": "^12.3.0",
-    "playwright": "^1.54.2"
+    "playwright": "^1.54.2",
+    "typescript": "^5.9.2"
   },
   "meteor": {
     "mainModule": {

tools/modern-tests/apps/react-router/server/main.js

@@ -5,8 +5,10 @@ import { StreamableHTTPClientTransport } from '@modelcontextprotocol/sdk/client/
 import '@helper/alias';
 import ReactAlias from '@react/alias';
 import './resolve-extensions/first';
+import { TypescriptEnabled } from './ts/helpers';
 
 console.log('@react/alias loaded', ReactAlias.version);
+console.log('TypescriptEnabled', TypescriptEnabled);
 
 async function insertLink({ title, url }) {
   await LinksCollection.insertAsync({ title, url, createdAt: new Date() });

tools/modern-tests/apps/react-router/server/ts/helpers.ts

@@ -0,0 +1 @@
+export const TypescriptEnabled: boolean = true;