lib,test: improves ERR_REQUIRE_ESM message

Fixes: nodejs#30599

Author: juanarbol

lib/internal/modules/cjs/loader.js

@@ -1195,29 +1195,39 @@ let warnRequireESM = true;
 Module._extensions['.js'] = function(module, filename) {
   if (filename.endsWith('.js')) {
     const pkg = readPackageScope(filename);
+    // Function require shouldn't be used in ES modules.
     if (pkg && pkg.data && pkg.data.type === 'module') {
+      const err = new ERR_REQUIRE_ESM(filename);
       if (warnRequireESM) {
         const parentPath = module.parent && module.parent.filename;
         const basename = parentPath &&
             path.basename(filename) === path.basename(parentPath) ?
           filename : path.basename(filename);
-        process.emitWarning(
+
+        const warningMsg =
           'require() of ES modules is not supported.\nrequire() of ' +
           `${filename} ${parentPath ? `from ${module.parent.filename} ` : ''}` +
           'is an ES module file as it is a .js file whose nearest parent ' +
           'package.json contains "type": "module" which defines all .js ' +
           'files in that package scope as ES modules.\nInstead rename ' +
           `${basename} to end in .cjs, change the requiring code to use ` +
           'import(), or remove "type": "module" from ' +
-          `${path.resolve(pkg.path, 'package.json')}.`,
+          `${path.resolve(pkg.path, 'package.json')}.\n` +
+          err.message;
+
+        // The error message should be (in this case) the as the warning.
+        // https://github.com/nodejs/node/issues/30599
+        err.message = warningMsg;
+        process.emitWarning(
+          warningMsg,
           undefined,
           undefined,
           undefined,
           true
         );
         warnRequireESM = false;
       }
-      throw new ERR_REQUIRE_ESM(filename);
+      throw err;
     }
   }
   const content = fs.readFileSync(filename, 'utf8');

test/es-module/test-cjs-esm-warn.js

@@ -37,4 +37,7 @@ child.on('close', common.mustCall((code, signal) => {
     `${pjson}.\n`));
   assert.ok(stderr.indexOf(
     'Error [ERR_REQUIRE_ESM]: Must use import to load ES Module') !== -1);
+
+  assert.strictEqual(
+    stderr.match(/Must use import to load ES Module/g).length, 2);
 }));