test_runner: enable in-source testing

Fixes: nodejs#45771

Author: debadree25

lib/internal/modules/esm/initialize_import_meta.js

@@ -3,12 +3,31 @@
 const { getOptionValue } = require('internal/options');
 const experimentalImportMetaResolve =
   getOptionValue('--experimental-import-meta-resolve');
+const isTestRunner = getOptionValue('--test');
 const {
   PromisePrototypeThen,
   PromiseReject,
+  ObjectAssign,
 } = primordials;
 const asyncESM = require('internal/process/esm_loader');
 
+let testModule;
+let runnerModule;
+
+function lazyLoadTestModule() {
+  if (testModule === undefined) {
+    testModule = require('internal/test_runner/harness');
+  }
+  return testModule;
+}
+
+function lazyLoadRunnerModule() {
+  if (runnerModule === undefined) {
+    runnerModule = require('internal/test_runner/runner');
+  }
+  return runnerModule;
+}
+
 function createImportMetaResolve(defaultParentUrl) {
   return async function resolve(specifier, parentUrl = defaultParentUrl) {
     return PromisePrototypeThen(
@@ -34,6 +53,21 @@ function initializeImportMeta(meta, context) {
   }
 
   meta.url = url;
+  if (isTestRunner) {
+    const { test, describe, it, before, after, beforeEach, afterEach } = lazyLoadTestModule();
+    const { run } = lazyLoadRunnerModule();
+    meta.test = test;
+    ObjectAssign(meta, {
+      after,
+      afterEach,
+      before,
+      beforeEach,
+      describe,
+      it,
+      run,
+      test,
+    });
+  }
 }
 
 module.exports = {