feat: No longer accept .js config files (#3519)

Author: willdurand

scripts/lib/mocha.js

@@ -20,10 +20,6 @@ const runMocha = (args, execMochaOptions = {}, coverageEnabled) => {
     shell.echo(`\nSetting mocha timeout from env var: ${MOCHA_TIMEOUT}\n`);
   }
 
-  // Pass testdouble node loader to support ESM module mocking and
-  // transpiling on the fly the tests modules.
-  binArgs.push('-n="loader=testdouble"');
-
   const res = spawnSync(binPath, binArgs, {
     ...execMochaOptions,
     env: {

src/config.js

@@ -12,29 +12,6 @@ import { UsageError, WebExtError } from './errors.js';
 
 const log = createLogger(import.meta.url);
 
-// NOTE: this error message is used in an interpolated string (while the other two help
-// messages are being logged as is).
-export const WARN_LEGACY_JS_EXT = [
-  'should be renamed to ".cjs" or ".mjs" file extension to ensure its format is not ambiguous.',
-  'Config files with the ".js" file extension are deprecated and will not be loaded anymore',
-  'in a future web-ext major version.',
-].join(' ');
-
-export const HELP_ERR_MODULE_FROM_ESM = [
-  'This config file belongs to a package.json file with "type" set to "module".',
-  'Change the file extension to ".cjs" or rewrite it as an ES module and use the ".mjs" file extension.',
-].join(' ');
-
-export const HELP_ERR_IMPORTEXPORT_CJS = [
-  'This config file is defined as an ES module, but it belongs to either a project directory',
-  'with a package.json file with "type" set to "commonjs" or one without any package.json file.',
-  'Change the file extension to ".mjs" to fix the config loading error.',
-].join(' ');
-
-const ERR_IMPORT_FROM_CJS = 'Cannot use import statement outside a module';
-const ERR_EXPORT_FROM_CJS = "Unexpected token 'export'";
-const ERR_MODULE_FROM_ESM = 'module is not defined in ES module scope';
-
 export function applyConfigToArgv({
   argv,
   argvFromCLI,
@@ -145,12 +122,18 @@ export async function loadJSConfigFile(filePath) {
     `Loading JS config file: "${filePath}" ` +
       `(resolved to "${resolvedFilePath}")`,
   );
+
   if (filePath.endsWith('.js')) {
-    log.warn(`WARNING: config file ${filePath} ${WARN_LEGACY_JS_EXT}`);
+    throw new UsageError(
+      ` Invalid config file "${resolvedFilePath}": the file extension should be` +
+        '".cjs" or ".mjs". More information at: https://mzl.la/web-ext-config-file',
+    );
   }
+
   let configObject;
   try {
     const nonce = `${Date.now()}-${Math.random()}`;
+
     let configModule;
     if (resolvedFilePath.endsWith('package.json')) {
       configModule = parseJSON(
@@ -165,35 +148,36 @@ export async function loadJSConfigFile(filePath) {
       // ES modules may expose both a default and named exports and so
       // we merge the named exports on top of what may have been set in
       // the default export.
+      if (filePath.endsWith('.cjs')) {
+        // Remove the additional 'module.exports' named export that Node.js >=
+        // 24 is returning from the dynamic import call (in addition to being
+        // also set on the default property as in Node.js < 24).
+        delete esmConfigMod['module.exports'];
+      }
       configObject = { ...configDefault, ...esmConfigMod };
     } else {
       configObject = { ...configModule };
     }
   } catch (error) {
-    log.debug('Handling error:', error);
-    let errorMessage = error.message;
-    if (error.message.startsWith(ERR_MODULE_FROM_ESM)) {
-      errorMessage = HELP_ERR_MODULE_FROM_ESM;
-    } else if (
-      [ERR_IMPORT_FROM_CJS, ERR_EXPORT_FROM_CJS].includes(error.message)
-    ) {
-      errorMessage = HELP_ERR_IMPORTEXPORT_CJS;
-    }
-    throw new UsageError(
-      `Cannot read config file: ${resolvedFilePath}\n` +
-        `Error: ${errorMessage}`,
+    const configFileError = new UsageError(
+      `Cannot read config file "${resolvedFilePath}":\n${error}`,
     );
+    configFileError.cause = error;
+    throw configFileError;
   }
+
   if (filePath.endsWith('package.json')) {
     log.debug('Looking for webExt key inside package.json file');
     configObject = configObject.webExt || {};
   }
+
   if (Object.keys(configObject).length === 0) {
     log.debug(
       `Config file ${resolvedFilePath} did not define any options. ` +
         'Did you set module.exports = {...}?',
     );
   }
+
   return configObject;
 }
 

src/program.js

@@ -331,6 +331,9 @@ export class Program {
       if (error.code) {
         log.error(`Error code: ${error.code}\n`);
       }
+      if (error.cause && adjustedArgv.verbose) {
+        log.error(`Error cause: ${error.cause.stack}\n`);
+      }
 
       log.debug(`Command executed: ${cmd}`);
 

tests/functional/test.cli.sign.js

@@ -13,11 +13,11 @@ import {
   reportCommandErrors,
 } from './common.js';
 
-// Put this as "web-ext-config.js" in the current directory, and replace
+// Put this as "web-ext-config.mjs" in the current directory, and replace
 // "FAKEAPIKEY" and "FAKEAPISECRET" with the actual values to enable
 // "web-ext sign" without passing those values via the CLI parameters.
 const GOOD_EXAMPLE_OF_WEB_EXT_CONFIG_JS = `
-module.exports = {
+export default {
   sign: {
     apiKey: "FAKEAPIKEY",
     apiSecret: "FAKEAPISECRET",
@@ -27,7 +27,7 @@ module.exports = {
 
 // Do NOT use this to specify the API key and secret. It won't work.
 const BAD_EXAMPLE_OF_WEB_EXT_CONFIG_JS = `
-module.exports = {
+export default {
   // Bad config: those should be under the "sign" key.
   apiKey: "FAKEAPIKEY",
   apiSecret: "FAKEAPISECRET",
@@ -86,7 +86,7 @@ describe('web-ext sign', () => {
   it('should use config file if required parameters are not in the arguments', () =>
     withTempAddonDir({ addonPath: minimalAddonPath }, (srcDir, tmpDir) => {
       writeFileSync(
-        path.join(tmpDir, 'web-ext-config.js'),
+        path.join(tmpDir, 'web-ext-config.mjs'),
         GOOD_EXAMPLE_OF_WEB_EXT_CONFIG_JS,
       );
 
@@ -120,7 +120,7 @@ describe('web-ext sign', () => {
 
   it('should show an error message if the api-key is not set in the config', () =>
     withTempAddonDir({ addonPath: minimalAddonPath }, (srcDir, tmpDir) => {
-      const configFilePath = path.join(tmpDir, 'web-ext-config.js');
+      const configFilePath = path.join(tmpDir, 'web-ext-config.mjs');
       writeFileSync(configFilePath, BAD_EXAMPLE_OF_WEB_EXT_CONFIG_JS);
       const argv = [
         'sign',
@@ -135,7 +135,7 @@ describe('web-ext sign', () => {
         assert.notEqual(exitCode, 0);
         assert.match(
           stderr,
-          /web-ext-config.js specified an unknown option: "apiKey"/,
+          /web-ext-config.mjs specified an unknown option: "apiKey"/,
         );
       });
     }));