Make the v8 core module work in Jest. (jestjs#2301)

integration_tests/__tests__/require-v8-module-test.js

@@ -0,0 +1,15 @@
+/**
+ * Copyright (c) 2014-present, Facebook, Inc. All rights reserved.
+ *
+ * This source code is licensed under the BSD-style license found in the
+ * LICENSE file in the root directory of this source tree. An additional grant
+ * of patent rights can be found in the PATENTS file in the same directory.
+ *
+ * @emails oncall+jsinfra
+ */
+
+test('v8 module', () => {
+  expect(() => require('v8')).not.toThrow();
+
+  expect(require('v8').getHeapStatistics().total_heap_size).toBeDefined();
+});

packages/jest-resolve/src/index.js

@@ -156,7 +156,13 @@ class Resolver {
   }
 
   isCoreModule(moduleName: string): boolean {
-    return this._options.hasCoreModules && resolve.isCore(moduleName);
+    return (
+      this._options.hasCoreModules &&
+      (
+        resolve.isCore(moduleName) ||
+        moduleName === 'v8'
+      )
+    );
   }
 
   getModule(name: string): ?Path {