esm: mordernize old tests

lib/path.js

@@ -1236,20 +1236,20 @@ const posix = {
   join(...args) {
     if (args.length === 0)
       return '.';
-    let joined;
+
+    const path = [];
     for (let i = 0; i < args.length; ++i) {
       const arg = args[i];
       validateString(arg, 'path');
       if (arg.length > 0) {
-        if (joined === undefined)
-          joined = arg;
-        else
-          joined += `/${arg}`;
+        path.push(arg);
       }
     }
-    if (joined === undefined)
+
+    if (path.length === 0)
       return '.';
-    return posix.normalize(joined);
+
+    return posix.normalize(ArrayPrototypeJoin(path, '/'));
   },
 
   /**

test/es-module/test-esm-type-field-errors.js

@@ -2,6 +2,7 @@
 const common = require('../common');
 const assert = require('assert');
 const exec = require('child_process').execFile;
+const { describe, it } = require('node:test');
 
 const mjsFile = require.resolve('../fixtures/es-modules/mjs-file.mjs');
 const cjsFile = require.resolve('../fixtures/es-modules/cjs-file.cjs');
@@ -13,25 +14,42 @@ const packageTypeModuleMain =
   require.resolve('../fixtures/es-modules/package-type-module/index.js');
 
 // Check that running `node` without options works
-expect('', mjsFile, '.mjs file');
-expect('', cjsFile, '.cjs file');
-expect('', packageTypeModuleMain, 'package-type-module');
-expect('', packageTypeCommonJsMain, 'package-type-commonjs');
-expect('', packageWithoutTypeMain, 'package-without-type');
-
-// Check that --input-type isn't allowed for files
-expect('--input-type=module', packageTypeModuleMain,
-       'ERR_INPUT_TYPE_NOT_ALLOWED', true);
-
-try {
-  require('../fixtures/es-modules/package-type-module/index.js');
-  assert.fail('Expected CJS to fail loading from type: module package.');
-} catch (e) {
-  assert.strictEqual(e.name, 'Error');
-  assert.strictEqual(e.code, 'ERR_REQUIRE_ESM');
-  assert(e.toString().match(/require\(\) of ES Module/g));
-  assert(e.message.match(/require\(\) of ES Module/g));
-}
+describe('ESM type field errors', { concurrency: true }, () => {
+  it('.cjs file', () => {
+    expect('', cjsFile, '.cjs file');
+  });
+
+  it('.mjs file', () => {
+    expect('', mjsFile, '.mjs file');
+  });
+
+  it('package.json with "type": "module"', () => {
+    expect('', packageTypeModuleMain, 'package-type-module');
+  });
+
+  it('package.json with "type": "commonjs"', () => {
+    expect('', packageTypeCommonJsMain, 'package-type-commonjs');
+  });
+
+  it('package.json with no "type" field', () => {
+    expect('', packageWithoutTypeMain, 'package-without-type');
+  });
+
+  it('--input-type=module disallowed for files', () => {
+    expect(
+      '--input-type=module',
+      packageTypeModuleMain,
+      'ERR_INPUT_TYPE_NOT_ALLOWED',
+      true,
+    );
+  });
+
+  it('--input-type=module disallowed for directories', () => {
+    assert.throws(() => require('../fixtures/es-modules/package-type-module/index.js'), {
+      code: 'ERR_REQUIRE_ESM'
+    });
+  });
+});
 
 function expect(opt = '', inputFile, want, wantsError = false) {
   const argv = [inputFile];