fix: error message on not installed module loaders for configuration (#2282)

Author: alexander-akait

packages/webpack-cli/lib/webpack-cli.js

@@ -717,7 +717,23 @@ class WebpackCLI {
             const interpreted = Object.keys(jsVariants).find((variant) => variant === ext);
 
             if (interpreted) {
-                rechoir.prepare(extensions, configPath);
+                try {
+                    rechoir.prepare(extensions, configPath);
+                } catch (error) {
+                    if (error.failures) {
+                        logger.error(`Unable load '${configPath}'`);
+                        logger.error(error.message);
+
+                        error.failures.forEach((failure) => {
+                            logger.error(failure.error.message);
+                        });
+                        logger.error('Please install one of them');
+                        process.exit(2);
+                    }
+
+                    logger.error(error);
+                    process.exit(2);
+                }
             }
 
             const { pathToFileURL } = require('url');

test/config-format/failure/failure.test.js

@@ -0,0 +1,19 @@
+const path = require('path');
+
+const { run } = require('../../utils/test-utils');
+
+describe('webpack cli', () => {
+    it('should support mjs config format', () => {
+        const { exitCode, stderr, stdout } = run(__dirname, ['-c', 'webpack.config.coffee']);
+
+        expect(exitCode).toBe(2);
+        expect(stderr).toContain(`Unable load '${path.resolve(__dirname, './webpack.config.coffee')}'`);
+        expect(stderr).toContain('Unable to use specified module loaders for ".coffee".');
+        expect(stderr).toContain("Cannot find module 'coffeescript/register'");
+        expect(stderr).toContain("Cannot find module 'coffee-script/register'");
+        expect(stderr).toContain("Cannot find module 'coffeescript'");
+        expect(stderr).toContain("Cannot find module 'coffee-script'");
+        expect(stderr).toContain('Please install one of them');
+        expect(stdout).toBeFalsy();
+    });
+});

test/config-format/failure/webpack.config.coffee

@@ -0,0 +1,10 @@
+path = require 'path'
+
+config =
+    mode: 'production'
+    entry: './main.js'
+    output:
+        path: path.resolve(__dirname, 'dist')
+        filename: 'foo.bundle.js'
+
+module.exports = config;