From 77558491541559b2b24d7c83da6db7ab8c3312b0 Mon Sep 17 00:00:00 2001
From: Karol Kuczmarski <kaon@fb.com>
Date: Tue, 2 May 2017 14:43:04 -0700
Subject: [PATCH 1/2] Add --listTests flag

---
 docs/en/CLI.md                                |  4 ++++
 .../__tests__/list_tests-test.js              | 21 +++++++++++++++++++
 .../list_tests/__tests__/dummy-test.js        | 14 +++++++++++++
 integration_tests/list_tests/package.json     |  5 +++++
 packages/jest-cli/src/cli/args.js             |  5 +++++
 packages/jest-cli/src/runJest.js              |  8 +++++++
 packages/jest-config/src/index.js             |  1 +
 packages/jest-config/src/normalize.js         |  1 +
 packages/jest-config/src/validConfig.js       |  1 +
 .../src/__tests__/fixtures/jestConfig.js      |  1 +
 types/Config.js                               |  1 +
 11 files changed, 62 insertions(+)
 create mode 100644 integration_tests/__tests__/list_tests-test.js
 create mode 100644 integration_tests/list_tests/__tests__/dummy-test.js
 create mode 100644 integration_tests/list_tests/package.json

diff --git a/docs/en/CLI.md b/docs/en/CLI.md
index ac04bcf3a26d..686a958b494d 100644
--- a/docs/en/CLI.md
+++ b/docs/en/CLI.md
@@ -133,6 +133,10 @@ Write test results to a file when the `--json` option is also specified.
 
 Will run all tests affected by file changes in the last commit made.
 
+### `--listTests`
+
+Lists all tests Jest will run given the other arguments, and exits.
+
 ### `--logHeapUsage`
 
 Logs the heap usage after every test. Useful to debug memory leaks. Use together with `--runInBand` and `--expose-gc` in node.
diff --git a/integration_tests/__tests__/list_tests-test.js b/integration_tests/__tests__/list_tests-test.js
new file mode 100644
index 000000000000..3b1d3952e2bf
--- /dev/null
+++ b/integration_tests/__tests__/list_tests-test.js
@@ -0,0 +1,21 @@
+/**
+ * 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
+ */
+'use strict';
+
+const runJest = require('../runJest');
+
+describe('--listTests flag', () => {
+  it('causes tests to be printed out as JSON', () => {
+    const {status, stdout} = runJest('list_tests', ['--listTests']);
+
+    expect(status).toBe(0);
+    expect(() => JSON.parse(stdout)).not.toThrow();
+  });
+});
diff --git a/integration_tests/list_tests/__tests__/dummy-test.js b/integration_tests/list_tests/__tests__/dummy-test.js
new file mode 100644
index 000000000000..79a9fbe8bc9c
--- /dev/null
+++ b/integration_tests/list_tests/__tests__/dummy-test.js
@@ -0,0 +1,14 @@
+/**
+ * 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.
+ */
+
+'use strict';
+
+it("isn't actually run", () => {
+  // (because it is only used for --listTests)
+  expect(true).toBe(false);
+});
diff --git a/integration_tests/list_tests/package.json b/integration_tests/list_tests/package.json
new file mode 100644
index 000000000000..148788b25446
--- /dev/null
+++ b/integration_tests/list_tests/package.json
@@ -0,0 +1,5 @@
+{
+  "jest": {
+    "testEnvironment": "node"
+  }
+}
diff --git a/packages/jest-cli/src/cli/args.js b/packages/jest-cli/src/cli/args.js
index 2b57b7aa1282..4d88b00ff6ee 100644
--- a/packages/jest-cli/src/cli/args.js
+++ b/packages/jest-cli/src/cli/args.js
@@ -196,6 +196,11 @@ const options = {
       'commit made.',
     type: 'boolean',
   },
+  listTests: {
+    default: false,
+    description: 'Lists all tests Jest will run given the arguments and exits.',
+    type: 'boolean',
+  },
   logHeapUsage: {
     default: undefined,
     description: 'Logs the heap usage after every test. Useful to debug ' +
diff --git a/packages/jest-cli/src/runJest.js b/packages/jest-cli/src/runJest.js
index b83cfc5879d5..968a65301099 100644
--- a/packages/jest-cli/src/runJest.js
+++ b/packages/jest-cli/src/runJest.js
@@ -175,6 +175,14 @@ const runJest = async (
   );
 
   allTests = sequencer.sort(allTests);
+
+  // With --listTests, simply print the test info as JSON and exit.
+  if (globalConfig.listTests) {
+    const testsJson = JSON.stringify(allTests, null, '  ');
+    new Console(pipe, pipe).log(testsJson);
+    process.exit(0);
+  }
+
   if (!allTests.length) {
     new Console(pipe, pipe).log(getNoTestsFoundMessage(testRunData, pattern));
   } else if (
diff --git a/packages/jest-config/src/index.js b/packages/jest-config/src/index.js
index 9e3d1b808d77..68145bbfcc2b 100644
--- a/packages/jest-config/src/index.js
+++ b/packages/jest-config/src/index.js
@@ -69,6 +69,7 @@ const getConfigs = (
       coverageThreshold: options.coverageThreshold,
       expand: options.expand,
       forceExit: options.forceExit,
+      listTests: options.listTests,
       logHeapUsage: options.logHeapUsage,
       mapCoverage: options.mapCoverage,
       noStackTrace: options.noStackTrace,
diff --git a/packages/jest-config/src/normalize.js b/packages/jest-config/src/normalize.js
index 05813f54f961..606b967407a2 100644
--- a/packages/jest-config/src/normalize.js
+++ b/packages/jest-config/src/normalize.js
@@ -376,6 +376,7 @@ function normalize(options: InitialOptions, argv: Object = {}) {
       case 'coverageThreshold':
       case 'expand':
       case 'globals':
+      case 'listTests':
       case 'logHeapUsage':
       case 'mapCoverage':
       case 'moduleDirectories':
diff --git a/packages/jest-config/src/validConfig.js b/packages/jest-config/src/validConfig.js
index 67f4a3ca014a..55a977edd812 100644
--- a/packages/jest-config/src/validConfig.js
+++ b/packages/jest-config/src/validConfig.js
@@ -43,6 +43,7 @@ module.exports = ({
   haste: {
     providesModuleNodeModules: ['react', 'react-native'],
   },
+  listTests: false,
   logHeapUsage: true,
   mapCoverage: false,
   moduleDirectories: ['node_modules'],
diff --git a/packages/jest-validate/src/__tests__/fixtures/jestConfig.js b/packages/jest-validate/src/__tests__/fixtures/jestConfig.js
index 3b7d3757e57b..de401153c11a 100644
--- a/packages/jest-validate/src/__tests__/fixtures/jestConfig.js
+++ b/packages/jest-validate/src/__tests__/fixtures/jestConfig.js
@@ -85,6 +85,7 @@ const validConfig = {
   haste: {
     providesModuleNodeModules: ['react', 'react-native'],
   },
+  listTests: true,
   logHeapUsage: true,
   moduleDirectories: ['node_modules'],
   moduleFileExtensions: ['js', 'json', 'jsx', 'node'],
diff --git a/types/Config.js b/types/Config.js
index 24df602ee164..0423a3883ee9 100644
--- a/types/Config.js
+++ b/types/Config.js
@@ -134,6 +134,7 @@ export type GlobalConfig = {|
   coverageThreshold: {global: {[key: string]: number}},
   expand: boolean,
   forceExit: boolean,
+  listTests: boolean,
   logHeapUsage: boolean,
   mapCoverage: boolean,
   noStackTrace: boolean,

From 533885b10f0e19c1b9a1fdfefc69d0e7c185266d Mon Sep 17 00:00:00 2001
From: cpojer <christoph.pojer@gmail.com>
Date: Wed, 3 May 2017 08:14:46 +0100
Subject: [PATCH 2/2] Fixes.

---
 docs/en/CLI.md                                        |  2 +-
 packages/jest-cli/src/cli/runCLI.js                   |  4 +++-
 packages/jest-cli/src/runJest.js                      | 11 +++++------
 packages/jest-config/src/index.js                     |  1 -
 packages/jest-config/src/normalize.js                 |  1 -
 packages/jest-config/src/validConfig.js               |  1 -
 .../src/__tests__/fixtures/jestConfig.js              |  1 -
 types/Config.js                                       |  1 -
 8 files changed, 9 insertions(+), 13 deletions(-)

diff --git a/docs/en/CLI.md b/docs/en/CLI.md
index 686a958b494d..b46d556b9c25 100644
--- a/docs/en/CLI.md
+++ b/docs/en/CLI.md
@@ -135,7 +135,7 @@ Will run all tests affected by file changes in the last commit made.
 
 ### `--listTests`
 
-Lists all tests Jest will run given the other arguments, and exits.
+Lists all tests as JSON that Jest will run given the arguments, and exits. This can be used together with `--findRelatedTests` to know which tests Jest will run.
 
 ### `--logHeapUsage`
 
diff --git a/packages/jest-cli/src/cli/runCLI.js b/packages/jest-cli/src/cli/runCLI.js
index cbe8643766d6..101e4a001b6f 100644
--- a/packages/jest-cli/src/cli/runCLI.js
+++ b/packages/jest-cli/src/cli/runCLI.js
@@ -75,7 +75,9 @@ module.exports = async (
       return watch(globalConfig, contexts, argv, pipe, hasteMapInstances);
     } else {
       const startRun = () => {
-        preRunMessage.print(pipe);
+        if (!argv.listTests) {
+          preRunMessage.print(pipe);
+        }
         runJest(
           globalConfig,
           contexts,
diff --git a/packages/jest-cli/src/runJest.js b/packages/jest-cli/src/runJest.js
index 968a65301099..a6824f4f5f9e 100644
--- a/packages/jest-cli/src/runJest.js
+++ b/packages/jest-cli/src/runJest.js
@@ -154,7 +154,7 @@ const runJest = async (
   pipe: stream$Writable | tty$WriteStream,
   testWatcher: TestWatcher,
   startRun: () => *,
-  onComplete: (testResults: any) => void,
+  onComplete: (testResults: any) => any,
 ) => {
   const maxWorkers = getMaxWorkers(argv);
   const pattern = getTestPathPattern(argv);
@@ -176,11 +176,10 @@ const runJest = async (
 
   allTests = sequencer.sort(allTests);
 
-  // With --listTests, simply print the test info as JSON and exit.
-  if (globalConfig.listTests) {
-    const testsJson = JSON.stringify(allTests, null, '  ');
-    new Console(pipe, pipe).log(testsJson);
-    process.exit(0);
+  if (argv.listTests) {
+    console.log(JSON.stringify(allTests.map(test => test.path)));
+    onComplete && onComplete({success: true});
+    return null;
   }
 
   if (!allTests.length) {
diff --git a/packages/jest-config/src/index.js b/packages/jest-config/src/index.js
index 68145bbfcc2b..9e3d1b808d77 100644
--- a/packages/jest-config/src/index.js
+++ b/packages/jest-config/src/index.js
@@ -69,7 +69,6 @@ const getConfigs = (
       coverageThreshold: options.coverageThreshold,
       expand: options.expand,
       forceExit: options.forceExit,
-      listTests: options.listTests,
       logHeapUsage: options.logHeapUsage,
       mapCoverage: options.mapCoverage,
       noStackTrace: options.noStackTrace,
diff --git a/packages/jest-config/src/normalize.js b/packages/jest-config/src/normalize.js
index 606b967407a2..05813f54f961 100644
--- a/packages/jest-config/src/normalize.js
+++ b/packages/jest-config/src/normalize.js
@@ -376,7 +376,6 @@ function normalize(options: InitialOptions, argv: Object = {}) {
       case 'coverageThreshold':
       case 'expand':
       case 'globals':
-      case 'listTests':
       case 'logHeapUsage':
       case 'mapCoverage':
       case 'moduleDirectories':
diff --git a/packages/jest-config/src/validConfig.js b/packages/jest-config/src/validConfig.js
index 55a977edd812..67f4a3ca014a 100644
--- a/packages/jest-config/src/validConfig.js
+++ b/packages/jest-config/src/validConfig.js
@@ -43,7 +43,6 @@ module.exports = ({
   haste: {
     providesModuleNodeModules: ['react', 'react-native'],
   },
-  listTests: false,
   logHeapUsage: true,
   mapCoverage: false,
   moduleDirectories: ['node_modules'],
diff --git a/packages/jest-validate/src/__tests__/fixtures/jestConfig.js b/packages/jest-validate/src/__tests__/fixtures/jestConfig.js
index de401153c11a..3b7d3757e57b 100644
--- a/packages/jest-validate/src/__tests__/fixtures/jestConfig.js
+++ b/packages/jest-validate/src/__tests__/fixtures/jestConfig.js
@@ -85,7 +85,6 @@ const validConfig = {
   haste: {
     providesModuleNodeModules: ['react', 'react-native'],
   },
-  listTests: true,
   logHeapUsage: true,
   moduleDirectories: ['node_modules'],
   moduleFileExtensions: ['js', 'json', 'jsx', 'node'],
diff --git a/types/Config.js b/types/Config.js
index 0423a3883ee9..24df602ee164 100644
--- a/types/Config.js
+++ b/types/Config.js
@@ -134,7 +134,6 @@ export type GlobalConfig = {|
   coverageThreshold: {global: {[key: string]: number}},
   expand: boolean,
   forceExit: boolean,
-  listTests: boolean,
   logHeapUsage: boolean,
   mapCoverage: boolean,
   noStackTrace: boolean,