test: unit test

Author: aryamohanan

packages/core/src/util/esm.js

@@ -10,7 +10,7 @@
  * Node.js v18.19 and above we are not supporting --experimental-loader flag
  */
 exports.hasExperimentalLoaderFlag = function hasExperimentalLoaderFlag() {
-  return (
+  return !!(
     (process.env.NODE_OPTIONS && process.env.NODE_OPTIONS.includes('--experimental-loader')) ||
     (process.execArgv[0] && process.execArgv[0].includes('--experimental-loader'))
   );
@@ -21,7 +21,7 @@ exports.hasExperimentalLoaderFlag = function hasExperimentalLoaderFlag() {
  * @returns {boolean} - True if esm-loader.mjs is present in Node options or execArgv, false otherwise.
  */
 exports.hasEsmLoaderFile = function hasEsmLoaderFile() {
-  return (
+  return !!(
     (process.env.NODE_OPTIONS && process.env.NODE_OPTIONS.includes('esm-loader.mjs')) ||
     process.execArgv.some(arg => arg.includes('esm-loader.mjs'))
   );

packages/core/test/util/esm_test.js

@@ -0,0 +1,57 @@
+/*
+ * (c) Copyright IBM Corp. 2025
+ */
+
+'use strict';
+
+const expect = require('chai').expect;
+const { hasExperimentalLoaderFlag, hasEsmLoaderFile } = require('../../src/util/esm');
+
+describe('util.esm', () => {
+  afterEach(() => {
+    delete process.env.NODE_OPTIONS;
+  });
+
+  describe('hasExperimentalLoaderFlag', () => {
+    it('should return true when --experimental-loader is in NODE_OPTIONS', () => {
+      process.env.NODE_OPTIONS = '--experimental-loader ./loader.mjs';
+      expect(hasExperimentalLoaderFlag()).to.be.true;
+    });
+
+    it('should return false when --experimental-loader is not present', () => {
+      delete process.env.NODE_OPTIONS;
+      expect(hasExperimentalLoaderFlag()).to.be.false;
+    });
+
+    it('should return false when NODE_OPTIONS has other flags', () => {
+      process.env.NODE_OPTIONS = '--max-old-space-size=4096';
+      expect(hasExperimentalLoaderFlag()).to.be.false;
+    });
+  });
+
+  describe('hasEsmLoaderFile', () => {
+    it('should return true when esm-loader.mjs is in NODE_OPTIONS', () => {
+      process.env.NODE_OPTIONS = '--experimental-loader ./esm-loader.mjs';
+      expect(hasEsmLoaderFile()).to.be.true;
+    });
+
+    it('should return true when esm-loader.mjs is in NODE_OPTIONS with other flags', () => {
+      process.env.NODE_OPTIONS = '--max-old-space-size=4096 --experimental-loader./esm-loader.mjs';
+      expect(hasEsmLoaderFile()).to.be.true;
+    });
+
+    it('should return false when NODE_OPTIONS is not set', () => {
+      expect(hasEsmLoaderFile()).to.be.false;
+    });
+
+    it('should return false when NODE_OPTIONS has other loader files', () => {
+      process.env.NODE_OPTIONS = '--import ./esm-register.mjs';
+      expect(hasEsmLoaderFile()).to.be.false;
+    });
+
+    it('should return false when NODE_OPTIONS is empty', () => {
+      process.env.NODE_OPTIONS = '';
+      expect(hasEsmLoaderFile()).to.be.false;
+    });
+  });
+});