Adds native support for PnP to jest

.gitignore

@@ -6,6 +6,8 @@
 /examples/*/node_modules/
 
 /e2e/*/node_modules
+/e2e/*/.pnp
+/e2e/*/.pnp.js
 !/e2e/presets/json/node_modules
 !/e2e/presets/js/node_modules
 /e2e/transform/*/coverage

CHANGELOG.md

@@ -2,6 +2,8 @@
 
 ### Features
 
+- `[jest-resolve]` Now supports PnP environment without plugins ([#8094](https://github.com/facebook/jest/pull/8094))
+
 ### Fixes
 
 - `[expect]` Compare DOM nodes even if there are multiple Node classes ([#8064](https://github.com/facebook/jest/pull/8064))

e2e/Utils.ts

@@ -20,7 +20,7 @@ export type RunResult = ExecaReturns & {
 };
 export const run = (cmd: string, cwd?: Config.Path): RunResult => {
   const args = cmd.split(/\s/).slice(1);
-  const spawnOptions = {cwd, reject: false};
+  const spawnOptions = {cwd, preferLocal: false, reject: false};
   const result = spawnSync(cmd.split(/\s/)[0], args, spawnOptions) as RunResult;
 
   // For compat with cross-spawn

e2e/__tests__/pnp.test.ts

@@ -0,0 +1,28 @@
+/**
+ * Copyright (c) Facebook, Inc. and its affiliates. 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.
+ */
+
+import path from 'path';
+import {skipSuiteOnWindows} from '@jest/test-utils';
+import {json as runWithJson} from '../runJest';
+import {run} from '../Utils';
+
+const DIR = path.resolve(__dirname, '..', 'pnp');
+
+// https://github.com/facebook/jest/pull/8094#issuecomment-471220694
+skipSuiteOnWindows();
+
+beforeEach(() => {
+  run('yarn', DIR);
+});
+
+it('sucessfully runs the tests inside `pnp/`', () => {
+  const {json} = runWithJson(DIR, ['--no-cache', '--coverage'], {
+    nodeOptions: `--require ${DIR}/.pnp.js`,
+  });
+  expect(json.success).toBe(true);
+  expect(json.numTotalTestSuites).toBe(1);
+});

e2e/pnp/__tests__/index.js

@@ -0,0 +1,14 @@
+/**
+ * Copyright (c) Facebook, Inc. and its affiliates. 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.
+ *
+ */
+
+const lib = require('foo');
+
+it('should work', () => {
+  expect(process.versions.pnp).toBeTruthy();
+  expect(lib()).toEqual(42);
+});

e2e/pnp/lib/index.js

@@ -0,0 +1,9 @@
+/**
+ * Copyright (c) Facebook, Inc. and its affiliates. 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.
+ *
+ */
+
+module.exports = () => 42;

e2e/pnp/lib/package.json

@@ -0,0 +1,3 @@
+{
+  "version": "0.0.0"
+}

e2e/pnp/package.json

@@ -0,0 +1,8 @@
+{
+  "dependencies": {
+    "foo": "link:./lib"
+  },
+  "installConfig": {
+    "pnp": true
+  }
+}

e2e/pnp/yarn.lock

@@ -0,0 +1,7 @@
+# THIS IS AN AUTOGENERATED FILE. DO NOT EDIT THIS FILE DIRECTLY.
+# yarn lockfile v1
+
+
+"foo@link:./lib":
+  version "0.0.0"
+  uid ""

e2e/runJest.ts

@@ -16,6 +16,7 @@ import {normalizeIcons} from './Utils';
 const JEST_PATH = path.resolve(__dirname, '../packages/jest-cli/bin/jest.js');
 
 type RunJestOptions = {
+  nodeOptions?: string;
   nodePath?: string;
   skipPkgJsonCheck?: boolean; // don't complain if can't find package.json
   stripAnsi?: boolean; // remove colors from stdout and stderr,
@@ -72,6 +73,7 @@ function spawnJest(
   }
   const env = Object.assign({}, process.env, {FORCE_COLOR: '0'});
 
+  if (options.nodeOptions) env['NODE_OPTIONS'] = options.nodeOptions;
   if (options.nodePath) env['NODE_PATH'] = options.nodePath;
 
   const spawnArgs = [JEST_PATH, ...(args || [])];

packages/jest-resolve/package.json

@@ -13,6 +13,7 @@
     "@jest/types": "^24.3.0",
     "browser-resolve": "^1.11.3",
     "chalk": "^2.0.1",
+    "jest-pnp-resolver": "^1.2.1",
     "realpath-native": "^1.1.0"
   },
   "devDependencies": {

packages/jest-resolve/src/defaultResolver.ts

@@ -8,6 +8,7 @@
 import fs from 'fs';
 import path from 'path';
 import browserResolve from 'browser-resolve';
+import pnpResolver from 'jest-pnp-resolver';
 import {Config} from '@jest/types';
 import isBuiltinModule from './isBuiltinModule';
 import nodeModulesPaths from './nodeModulesPaths';
@@ -26,6 +27,11 @@ export default function defaultResolver(
   path: Config.Path,
   options: ResolverOptions,
 ): Config.Path {
+  // @ts-ignore: the "pnp" version named isn't in DefinitelyTyped
+  if (process.versions.pnp) {
+    return pnpResolver(path, options);
+  }
+
   const resolve = options.browser ? browserResolve.sync : resolveSync;
 
   return resolve(path, {

yarn.lock

@@ -7654,6 +7654,11 @@ jest-junit@^6.2.1:
     strip-ansi "^4.0.0"
     xml "^1.0.1"
 
+jest-pnp-resolver@^1.2.1:
+  version "1.2.1"
+  resolved "https://registry.yarnpkg.com/jest-pnp-resolver/-/jest-pnp-resolver-1.2.1.tgz#ecdae604c077a7fbc70defb6d517c3c1c898923a"
+  integrity sha512-pgFw2tm54fzgYvc/OHrnysABEObZCUNFnhjoRjaVOCN8NYc032/gVjPaHD4Aq6ApkSieWtfKAFQtmDKAmhupnQ==
+
 jest-serializer@24.0.0-alpha.6:
   version "24.0.0-alpha.6"
   resolved "https://registry.yarnpkg.com/jest-serializer/-/jest-serializer-24.0.0-alpha.6.tgz#27d2fee4b1a85698717a30c3ec2ab80767312597"