feat(runtime): support require.resolve.paths

CHANGELOG.md

@@ -2,6 +2,7 @@
 
 ### Features
 
+- `[jest-runtime]` Support `require.resolve.paths`.
 - `[jest-runtime]` Support `paths` option for `require.resolve`.
 - `[jest-snapshot]` Introduce `toMatchInlineSnapshot` and `toThrowErrorMatchingInlineSnapshot` matchers ([#6380](https://github.com/facebook/jest/pull/6380))
 

e2e/__tests__/resolve-get-paths.test.js

@@ -0,0 +1,16 @@
+/**
+ * Copyright (c) 2014-present, Facebook, Inc. All rights reserved.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ *
+ * @flow
+ */
+'use strict';
+
+const runJest = require('../runJest');
+
+test('require.resolve.paths', () => {
+  const {status} = runJest('resolve-get-paths');
+  expect(status).toBe(0);
+});

e2e/resolve-get-paths/__tests__/resolve-get-paths.test.js

@@ -0,0 +1,24 @@
+/**
+ * Copyright (c) 2014-present, Facebook, Inc. All rights reserved.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+'use strict';
+
+import {resolve} from 'path';
+
+test('returns the resolve path for a relative path', () => {
+  expect(require.resolve.paths('./mod.js')).toEqual([resolve(__dirname)]);
+});
+
+test('returns the resolve paths for a node_module', () => {
+  expect(require.resolve.paths('mod').slice(0, 2)).toEqual([
+    resolve(__dirname, 'node_modules'),
+    resolve(__dirname, '..', 'node_modules'),
+  ]);
+});
+
+test('returns null for a native node module', () => {
+  expect(require.resolve.paths('fs')).toBeNull();
+});

e2e/resolve-get-paths/package.json

@@ -0,0 +1,5 @@
+{
+  "jest": {
+    "testEnvironment": "node"
+  }
+}

packages/jest-runtime/src/index.js

@@ -530,6 +530,27 @@ class Runtime {
     return this._resolveModule(from, moduleName);
   }
 
+  _requireResolvePaths(from: Path, moduleName?: string) {
+    if (moduleName == null) {
+      throw new Error(
+        'The first argument to require.resolve.paths must be a string. Received null or undefined.',
+      );
+    }
+    if (!moduleName.length) {
+      throw new Error(
+        'The first argument to require.resolve.paths must not be the empty string.',
+      );
+    }
+
+    if (moduleName[0] === '.') {
+      return [path.resolve(from, '..')];
+    }
+    if (this._resolver.isCoreModule(moduleName)) {
+      return null;
+    }
+    return this._resolver.getModulePaths(path.resolve(from, '..'));
+  }
+
   _execModule(
     localModule: Module,
     options: ?InternalModuleOptions,
@@ -758,6 +779,8 @@ class Runtime {
     moduleRequire.requireMock = this.requireMock.bind(this, from.filename);
     moduleRequire.resolve = (moduleName, options) =>
       this._requireResolve(from.filename, moduleName, options);
+    moduleRequire.resolve.paths = moduleName =>
+      this._requireResolvePaths(from.filename, moduleName);
     Object.defineProperty(
       moduleRequire,
       'main',