From f74adbb789a09b9e297194bcf78fbbeeb78b301f Mon Sep 17 00:00:00 2001
From: Ran Yitzhaki <ranyitzhaki@gmail.com>
Date: Fri, 23 Mar 2018 01:20:20 +0200
Subject: [PATCH 1/3] assign process.env.JEST_WORKER_ID=0 when on runInBand
 mode

---
 .../src/__tests__/test_runner.test.js         | 19 +++++++++++++++++++
 packages/jest-runner/src/index.js             |  1 +
 2 files changed, 20 insertions(+)

diff --git a/packages/jest-runner/src/__tests__/test_runner.test.js b/packages/jest-runner/src/__tests__/test_runner.test.js
index f05ab6c6dc4d..aa26eba2f969 100644
--- a/packages/jest-runner/src/__tests__/test_runner.test.js
+++ b/packages/jest-runner/src/__tests__/test_runner.test.js
@@ -86,3 +86,22 @@ test('does not inject the rawModuleMap in serial mode', () => {
       ]);
     });
 });
+
+test('assign process.env.JEST_WORKER_ID = 0 when in runInBand mode', () => {
+  const globalConfig = {maxWorkers: 1, watch: false};
+  const config = {rootDir: '/path/'};
+  const context = {config};
+
+  return new TestRunner(globalConfig)
+    .runTests(
+      [{context, path: './file.test.js'}],
+      new TestWatcher({isWatchMode: globalConfig.watch}),
+      () => {},
+      () => {},
+      () => {},
+      {serial: true},
+    )
+    .then(() => {
+      expect(process.env.JEST_WORKER_ID).toBe('0');
+    });
+});
diff --git a/packages/jest-runner/src/index.js b/packages/jest-runner/src/index.js
index f4a2ce92c1ab..154d4ff3bb6e 100644
--- a/packages/jest-runner/src/index.js
+++ b/packages/jest-runner/src/index.js
@@ -61,6 +61,7 @@ class TestRunner {
     onResult: OnTestSuccess,
     onFailure: OnTestFailure,
   ) {
+    process.env.JEST_WORKER_ID = '0';
     const mutex = throat(1);
     return tests.reduce(
       (promise, test) =>

From 73ddfac4c82b2dbb127981852be152661a6ed0e6 Mon Sep 17 00:00:00 2001
From: Ran Yitzhaki <ranyitzhaki@gmail.com>
Date: Fri, 23 Mar 2018 01:29:31 +0200
Subject: [PATCH 2/3] update changelog

---
 CHANGELOG.md | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index d7b5520066a1..ce074bed6ac9 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -37,6 +37,8 @@
 
 ### Fixes
 
+* `[jest-runner]` Assign `process.env.JEST_WORKER_ID="0"` when in runInBand mode
+  ([#5860](https://github.com/facebook/jest/pull/5860))
 * `[jest-cli]` Add descriptive error message when trying to use
   `globalSetup`/`globalTeardown` file that doesn't export a function.
   ([#5835](https://github.com/facebook/jest/pull/5835))

From 2772d6bbce38c7998c6f1e8b8c7de5b1fd145ec4 Mon Sep 17 00:00:00 2001
From: Ran Yitzhaki <ranyitzhaki@gmail.com>
Date: Fri, 23 Mar 2018 01:41:33 +0200
Subject: [PATCH 3/3] change JEST_WORKER_ID in runInBand mode from 0 to 1

---
 CHANGELOG.md                                           | 2 +-
 packages/jest-runner/src/__tests__/test_runner.test.js | 4 ++--
 packages/jest-runner/src/index.js                      | 2 +-
 3 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index ce074bed6ac9..016da2e36835 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -37,7 +37,7 @@
 
 ### Fixes
 
-* `[jest-runner]` Assign `process.env.JEST_WORKER_ID="0"` when in runInBand mode
+* `[jest-runner]` Assign `process.env.JEST_WORKER_ID="1"` when in runInBand mode
   ([#5860](https://github.com/facebook/jest/pull/5860))
 * `[jest-cli]` Add descriptive error message when trying to use
   `globalSetup`/`globalTeardown` file that doesn't export a function.
diff --git a/packages/jest-runner/src/__tests__/test_runner.test.js b/packages/jest-runner/src/__tests__/test_runner.test.js
index aa26eba2f969..ced1c934a8cc 100644
--- a/packages/jest-runner/src/__tests__/test_runner.test.js
+++ b/packages/jest-runner/src/__tests__/test_runner.test.js
@@ -87,7 +87,7 @@ test('does not inject the rawModuleMap in serial mode', () => {
     });
 });
 
-test('assign process.env.JEST_WORKER_ID = 0 when in runInBand mode', () => {
+test('assign process.env.JEST_WORKER_ID = 1 when in runInBand mode', () => {
   const globalConfig = {maxWorkers: 1, watch: false};
   const config = {rootDir: '/path/'};
   const context = {config};
@@ -102,6 +102,6 @@ test('assign process.env.JEST_WORKER_ID = 0 when in runInBand mode', () => {
       {serial: true},
     )
     .then(() => {
-      expect(process.env.JEST_WORKER_ID).toBe('0');
+      expect(process.env.JEST_WORKER_ID).toBe('1');
     });
 });
diff --git a/packages/jest-runner/src/index.js b/packages/jest-runner/src/index.js
index 154d4ff3bb6e..2f4dd7243697 100644
--- a/packages/jest-runner/src/index.js
+++ b/packages/jest-runner/src/index.js
@@ -61,7 +61,7 @@ class TestRunner {
     onResult: OnTestSuccess,
     onFailure: OnTestFailure,
   ) {
-    process.env.JEST_WORKER_ID = '0';
+    process.env.JEST_WORKER_ID = '1';
     const mutex = throat(1);
     return tests.reduce(
       (promise, test) =>