From 8d598dd1e610acee796468e772cbc15613ff2451 Mon Sep 17 00:00:00 2001
From: Nico Jansen <jansennico@gmail.com>
Date: Sun, 2 Oct 2022 13:20:59 +0200
Subject: [PATCH 01/24] feat(config): add read initial options helper

Add `readInitialOptions` function to the jest-config package. This is a helper function that can be useful for consumers of the jest programmatic api. It exposes the functionality that jest uses to read config from different sources.
---
 .../__fixtures__/async-config/jest.config.js  |   5 +
 .../src/__fixtures__/js-config/jest.config.js |   3 +
 .../__fixtures__/json-config/jest.config.json |   3 +
 .../multiple-config-files/jest.config.js      |   3 +
 .../multiple-config-files/jest.config.json    |   3 +
 .../src/__fixtures__/pkg-config/package.json  |   5 +
 .../src/__fixtures__/ts-config/jest.config.ts |   3 +
 .../src/__tests__/readInitialOptions.test.ts  | 118 +++++++++++++++
 packages/jest-config/src/index.ts             | 138 ++++++++++++------
 9 files changed, 235 insertions(+), 46 deletions(-)
 create mode 100644 packages/jest-config/src/__fixtures__/async-config/jest.config.js
 create mode 100644 packages/jest-config/src/__fixtures__/js-config/jest.config.js
 create mode 100644 packages/jest-config/src/__fixtures__/json-config/jest.config.json
 create mode 100644 packages/jest-config/src/__fixtures__/multiple-config-files/jest.config.js
 create mode 100644 packages/jest-config/src/__fixtures__/multiple-config-files/jest.config.json
 create mode 100644 packages/jest-config/src/__fixtures__/pkg-config/package.json
 create mode 100644 packages/jest-config/src/__fixtures__/ts-config/jest.config.ts
 create mode 100644 packages/jest-config/src/__tests__/readInitialOptions.test.ts

diff --git a/packages/jest-config/src/__fixtures__/async-config/jest.config.js b/packages/jest-config/src/__fixtures__/async-config/jest.config.js
new file mode 100644
index 000000000000..7d0206905c19
--- /dev/null
+++ b/packages/jest-config/src/__fixtures__/async-config/jest.config.js
@@ -0,0 +1,5 @@
+module.exports = async function () {
+  return {
+    jestConfig: 'async-config',
+  };
+};
diff --git a/packages/jest-config/src/__fixtures__/js-config/jest.config.js b/packages/jest-config/src/__fixtures__/js-config/jest.config.js
new file mode 100644
index 000000000000..ca94a9b4d2f6
--- /dev/null
+++ b/packages/jest-config/src/__fixtures__/js-config/jest.config.js
@@ -0,0 +1,3 @@
+module.exports = {
+  jestConfig: 'jest.config.js',
+};
diff --git a/packages/jest-config/src/__fixtures__/json-config/jest.config.json b/packages/jest-config/src/__fixtures__/json-config/jest.config.json
new file mode 100644
index 000000000000..bf022d79f271
--- /dev/null
+++ b/packages/jest-config/src/__fixtures__/json-config/jest.config.json
@@ -0,0 +1,3 @@
+{
+  "jestConfig": "jest.config.json"
+}
diff --git a/packages/jest-config/src/__fixtures__/multiple-config-files/jest.config.js b/packages/jest-config/src/__fixtures__/multiple-config-files/jest.config.js
new file mode 100644
index 000000000000..ca94a9b4d2f6
--- /dev/null
+++ b/packages/jest-config/src/__fixtures__/multiple-config-files/jest.config.js
@@ -0,0 +1,3 @@
+module.exports = {
+  jestConfig: 'jest.config.js',
+};
diff --git a/packages/jest-config/src/__fixtures__/multiple-config-files/jest.config.json b/packages/jest-config/src/__fixtures__/multiple-config-files/jest.config.json
new file mode 100644
index 000000000000..bf022d79f271
--- /dev/null
+++ b/packages/jest-config/src/__fixtures__/multiple-config-files/jest.config.json
@@ -0,0 +1,3 @@
+{
+  "jestConfig": "jest.config.json"
+}
diff --git a/packages/jest-config/src/__fixtures__/pkg-config/package.json b/packages/jest-config/src/__fixtures__/pkg-config/package.json
new file mode 100644
index 000000000000..766501789210
--- /dev/null
+++ b/packages/jest-config/src/__fixtures__/pkg-config/package.json
@@ -0,0 +1,5 @@
+{
+  "jest": {
+    "jestConfig": "package.json"
+  }
+}
diff --git a/packages/jest-config/src/__fixtures__/ts-config/jest.config.ts b/packages/jest-config/src/__fixtures__/ts-config/jest.config.ts
new file mode 100644
index 000000000000..64d592d87ceb
--- /dev/null
+++ b/packages/jest-config/src/__fixtures__/ts-config/jest.config.ts
@@ -0,0 +1,3 @@
+export default {
+  jestConfig: 'jest.config.ts',
+};
diff --git a/packages/jest-config/src/__tests__/readInitialOptions.test.ts b/packages/jest-config/src/__tests__/readInitialOptions.test.ts
new file mode 100644
index 000000000000..d16512e9b763
--- /dev/null
+++ b/packages/jest-config/src/__tests__/readInitialOptions.test.ts
@@ -0,0 +1,118 @@
+import path = require('path');
+import type {Config} from 'jest-runner';
+import {readInitialOptions} from '../index';
+
+function resolveFixture(...pathSegments: Array<string>) {
+  return path.resolve(__dirname, '..', '__fixtures__', ...pathSegments);
+}
+
+describe(readInitialOptions.name, () => {
+  test('should read from the cwd by default', async () => {
+    const configFile = resolveFixture('js-config', 'jest.config.js');
+    const rootDir = resolveFixture('js-config');
+    jest.spyOn(process, 'cwd').mockReturnValue(rootDir);
+    const {config, configPath} = await readInitialOptions();
+    expect(config).toEqual({jestConfig: 'jest.config.js', rootDir});
+    expect(configPath).toEqual(configFile);
+  });
+  test('should read a jest.config.js file', async () => {
+    const configFile = resolveFixture('js-config', 'jest.config.js');
+    const rootDir = resolveFixture('js-config');
+    const {config, configPath} = await readInitialOptions(configFile);
+    expect(config).toEqual({jestConfig: 'jest.config.js', rootDir});
+    expect(configPath).toEqual(configFile);
+  });
+  test('should read a package.json file', async () => {
+    const configFile = resolveFixture('pkg-config', 'package.json');
+    const rootDir = resolveFixture('pkg-config');
+    const {config, configPath} = await readInitialOptions(configFile);
+    expect(config).toEqual({jestConfig: 'package.json', rootDir});
+    expect(configPath).toEqual(configFile);
+  });
+  test('should read a jest.config.ts file', async () => {
+    const configFile = resolveFixture('ts-config', 'jest.config.ts');
+    const rootDir = resolveFixture('ts-config');
+    const {config, configPath} = await readInitialOptions(configFile);
+    expect(config).toEqual({jestConfig: 'jest.config.ts', rootDir});
+    expect(configPath).toEqual(configFile);
+  });
+  test('should read a jest.config.json file', async () => {
+    const configFile = resolveFixture('json-config', 'jest.config.json');
+    const rootDir = resolveFixture('json-config');
+    const {config, configPath} = await readInitialOptions(configFile);
+    expect(config).toEqual({jestConfig: 'jest.config.json', rootDir});
+    expect(configPath).toEqual(configFile);
+  });
+  test('should read a jest config exporting an async function', async () => {
+    const configFile = resolveFixture('async-config', 'jest.config.js');
+    const rootDir = resolveFixture('async-config');
+    const {config, configPath} = await readInitialOptions(configFile);
+    expect(config).toEqual({jestConfig: 'async-config', rootDir});
+    expect(configPath).toEqual(configFile);
+  });
+  test('should be able to use serialized jest config', async () => {
+    const inputConfig = {jestConfig: 'serialized'};
+    const {config, configPath} = await readInitialOptions(
+      JSON.stringify(inputConfig),
+    );
+    expect(config).toEqual({...inputConfig, rootDir: process.cwd()});
+    expect(configPath).toEqual(null);
+  });
+
+  test('should allow deserialized options', async () => {
+    const inputConfig = {jestConfig: 'deserialized'};
+    const {config, configPath} = await readInitialOptions(undefined, {
+      packageRootOrConfig: inputConfig as Config.InitialOptions,
+      parentConfigDirname: process.cwd(),
+    });
+    expect(config).toEqual({...inputConfig, rootDir: process.cwd()});
+    expect(configPath).toEqual(null);
+  });
+
+  test('should be able to skip config reading, instead read from cwd', async () => {
+    const expectedConfigFile = resolveFixture(
+      'json-config',
+      'jest.config.json',
+    );
+    jest.spyOn(process, 'cwd').mockReturnValue(resolveFixture('json-config'));
+    const {config, configPath} = await readInitialOptions(
+      resolveFixture('js-config', 'jest.config.js'),
+      {
+        readFromCwdInstead: true,
+      },
+    );
+    expect(config).toEqual({
+      jestConfig: 'jest.config.json',
+      rootDir: path.dirname(expectedConfigFile),
+    });
+    expect(configPath).toEqual(expectedConfigFile);
+  });
+
+  test('should give an error when there are multiple config files', async () => {
+    const cwd = resolveFixture('multiple-config-files');
+    jest.spyOn(process, 'cwd').mockReturnValue(cwd);
+    const error: Error = await readInitialOptions().catch(error => error);
+    expect(error.message).toContain('Multiple configurations found');
+    expect(error.message).toContain(
+      resolveFixture('multiple-config-files', 'jest.config.js'),
+    );
+    expect(error.message).toContain(
+      resolveFixture('multiple-config-files', 'jest.config.json'),
+    );
+  });
+
+  test('should be able to ignore multiple config files error', async () => {
+    const cwd = resolveFixture('multiple-config-files');
+    jest.spyOn(process, 'cwd').mockReturnValue(cwd);
+    const {config, configPath} = await readInitialOptions(undefined, {
+      skipMultipleConfigError: true,
+    });
+    expect(config).toEqual({
+      jestConfig: 'jest.config.js',
+      rootDir: resolveFixture('multiple-config-files'),
+    });
+    expect(configPath).toEqual(
+      resolveFixture('multiple-config-files', 'jest.config.js'),
+    );
+  });
+});
diff --git a/packages/jest-config/src/index.ts b/packages/jest-config/src/index.ts
index de947b1d5de2..14626084aed9 100644
--- a/packages/jest-config/src/index.ts
+++ b/packages/jest-config/src/index.ts
@@ -43,56 +43,18 @@ export async function readConfig(
   projectIndex = Infinity,
   skipMultipleConfigError = false,
 ): Promise<ReadConfig> {
-  let rawOptions: Config.InitialOptions;
-  let configPath = null;
-
-  if (typeof packageRootOrConfig !== 'string') {
-    if (parentConfigDirname) {
-      rawOptions = packageRootOrConfig;
-      rawOptions.rootDir = rawOptions.rootDir
-        ? replaceRootDirInPath(parentConfigDirname, rawOptions.rootDir)
-        : parentConfigDirname;
-    } else {
-      throw new Error(
-        'Jest: Cannot use configuration as an object without a file path.',
-      );
-    }
-  } else if (isJSONString(argv.config)) {
-    // A JSON string was passed to `--config` argument and we can parse it
-    // and use as is.
-    let config;
-    try {
-      config = JSON.parse(argv.config);
-    } catch {
-      throw new Error(
-        'There was an error while parsing the `--config` argument as a JSON string.',
-      );
-    }
-
-    // NOTE: we might need to resolve this dir to an absolute path in the future
-    config.rootDir = config.rootDir || packageRootOrConfig;
-    rawOptions = config;
-    // A string passed to `--config`, which is either a direct path to the config
-    // or a path to directory containing `package.json`, `jest.config.js` or `jest.config.ts`
-  } else if (!skipArgvConfigOption && typeof argv.config == 'string') {
-    configPath = resolveConfigPath(
-      argv.config,
-      process.cwd(),
-      skipMultipleConfigError,
-    );
-    rawOptions = await readConfigFileAndSetRootDir(configPath);
-  } else {
-    // Otherwise just try to find config in the current rootDir.
-    configPath = resolveConfigPath(
+  const {config: initialOptions, configPath} = await readInitialOptions(
+    argv?.config,
+    {
       packageRootOrConfig,
-      process.cwd(),
+      parentConfigDirname,
+      readFromCwdInstead: skipArgvConfigOption,
       skipMultipleConfigError,
-    );
-    rawOptions = await readConfigFileAndSetRootDir(configPath);
-  }
+    },
+  );
 
   const {options, hasDeprecationWarnings} = await normalize(
-    rawOptions,
+    initialOptions,
     argv,
     configPath,
     projectIndex,
@@ -267,6 +229,90 @@ This usually means that your ${chalk.bold(
   }
 };
 
+/**
+/**
+ * Reads the jest config, without validating them or filling it out with defaults.
+ * @param config The path to the file or serialized config.
+ * @param param1 Additional options
+ * @returns The raw initial config (not validated)
+ */
+export async function readInitialOptions(
+  config?: string,
+  {
+    packageRootOrConfig = process.cwd(),
+    parentConfigDirname = null,
+    readFromCwdInstead = false,
+    skipMultipleConfigError = false,
+  }: {
+    /**
+     * The package root or deserialized config (default is cwd)
+     */
+    packageRootOrConfig?: string | Config.InitialOptions;
+    /**
+     * When the `packageRootOrConfig` contains config, this parameter should
+     * contain the dirname of the parent config
+     */
+    parentConfigDirname?: null | string;
+    /**
+     * Indicates whether or not to read the specified config file from disk.
+     * When true, jest will read try to read config from the current working directory.
+     * (default is false)
+     */
+    readFromCwdInstead?: boolean;
+    /**
+     * Indicates whether or not to ignore the error of jest finding multiple config files.
+     * (default is false)
+     */
+    skipMultipleConfigError?: boolean;
+  } = {},
+): Promise<{config: Config.InitialOptions; configPath: string | null}> {
+  if (typeof packageRootOrConfig !== 'string') {
+    if (parentConfigDirname) {
+      const rawOptions = packageRootOrConfig;
+      rawOptions.rootDir = rawOptions.rootDir
+        ? replaceRootDirInPath(parentConfigDirname, rawOptions.rootDir)
+        : parentConfigDirname;
+      return {config: rawOptions, configPath: null};
+    } else {
+      throw new Error(
+        'Jest: Cannot use configuration as an object without a file path.',
+      );
+    }
+  } else if (isJSONString(config)) {
+    // A JSON string was passed to `--config` argument and we can parse it
+    // and use as is.
+    let initialOptions;
+    try {
+      initialOptions = JSON.parse(config);
+    } catch {
+      throw new Error(
+        'There was an error while parsing the `--config` argument as a JSON string.',
+      );
+    }
+
+    // NOTE: we might need to resolve this dir to an absolute path in the future
+    initialOptions.rootDir = initialOptions.rootDir || packageRootOrConfig;
+    return {config: initialOptions, configPath: null};
+    // A string passed to `--config`, which is either a direct path to the config
+    // or a path to directory containing `package.json`, `jest.config.js` or `jest.config.ts`
+  } else if (!readFromCwdInstead && typeof config == 'string') {
+    const configPath = resolveConfigPath(
+      config,
+      process.cwd(),
+      skipMultipleConfigError,
+    );
+    return {config: await readConfigFileAndSetRootDir(configPath), configPath};
+  } else {
+    // Otherwise just try to find config in the current rootDir.
+    const configPath = resolveConfigPath(
+      packageRootOrConfig,
+      process.cwd(),
+      skipMultipleConfigError,
+    );
+    return {config: await readConfigFileAndSetRootDir(configPath), configPath};
+  }
+}
+
 // Possible scenarios:
 //  1. jest --config config.json
 //  2. jest --projects p1 p2

From aabb8de896f2f3a076be8927e6a8699e273c4ac8 Mon Sep 17 00:00:00 2001
From: Nico Jansen <jansennico@gmail.com>
Date: Sun, 2 Oct 2022 13:21:23 +0200
Subject: [PATCH 02/24] Enable experimental-vm-modules to run jest.

---
 .vscode/launch.json | 3 +++
 package.json        | 2 +-
 2 files changed, 4 insertions(+), 1 deletion(-)

diff --git a/.vscode/launch.json b/.vscode/launch.json
index 5de4feacd272..8802afcba97c 100644
--- a/.vscode/launch.json
+++ b/.vscode/launch.json
@@ -13,6 +13,9 @@
       "console": "integratedTerminal",
       "internalConsoleOptions": "neverOpen",
       "disableOptimisticBPs": true,
+      "env": {
+        "NODE_OPTIONS": "--experimental-vm-modules"
+      },
       "windows": {
         "program": "${workspaceFolder}/node_modules/jest/bin/jest"
       }
diff --git a/package.json b/package.json
index 425b52667541..09110bd7b714 100644
--- a/package.json
+++ b/package.json
@@ -95,7 +95,7 @@
     "clean-e2e": "node ./scripts/cleanE2e.mjs",
     "crowdin:upload": "echo 'Uploading sources to Crowdin' && crowdin upload sources --config ./crowdin.yaml",
     "crowdin:download": "echo 'Downloading translations from Crowdin' && crowdin download --config ./crowdin.yaml",
-    "jest": "node ./packages/jest-cli/bin/jest.js",
+    "jest": "node --experimental-vm-modules ./packages/jest-cli/bin/jest.js",
     "jest-jasmine": "JEST_JASMINE=1 yarn jest",
     "jest-jasmine-ci": "yarn jest-jasmine --color --config jest.config.ci.mjs",
     "jest-coverage": "yarn jest --coverage",

From e9b5c8700e194ed4e8a8bc9a1b88dbc439e21b1b Mon Sep 17 00:00:00 2001
From: Nico Jansen <jansennico@gmail.com>
Date: Sun, 2 Oct 2022 13:28:23 +0200
Subject: [PATCH 03/24] Update changelog

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

diff --git a/CHANGELOG.md b/CHANGELOG.md
index e1ef3104cc39..91c521c46c17 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -4,6 +4,7 @@
 
 - `[jest-core]` Enable testResultsProcessor to be async ([#13343](https://github.com/facebook/jest/pull/13343))
 - `[expect, @jest/expect-utils]` Allow `isA` utility to take a type argument ([#13355](https://github.com/facebook/jest/pull/13355))
+- `[jest-config]` Add `readInitialConfig` utility function ([#13356](https://github.com/facebook/jest/pull/13356))
 
 ### Fixes
 

From b6276fbc57925710e63681cc82293b4f72d74455 Mon Sep 17 00:00:00 2001
From: Nico Jansen <jansennico@gmail.com>
Date: Sun, 2 Oct 2022 13:30:09 +0200
Subject: [PATCH 04/24] Add copyright headers

---
 .../src/__fixtures__/async-config/jest.config.js            | 6 ++++++
 .../jest-config/src/__fixtures__/js-config/jest.config.js   | 6 ++++++
 .../src/__fixtures__/multiple-config-files/jest.config.js   | 6 ++++++
 .../jest-config/src/__fixtures__/ts-config/jest.config.ts   | 6 ++++++
 .../jest-config/src/__tests__/readInitialOptions.test.ts    | 6 ++++++
 5 files changed, 30 insertions(+)

diff --git a/packages/jest-config/src/__fixtures__/async-config/jest.config.js b/packages/jest-config/src/__fixtures__/async-config/jest.config.js
index 7d0206905c19..00df2a4f3837 100644
--- a/packages/jest-config/src/__fixtures__/async-config/jest.config.js
+++ b/packages/jest-config/src/__fixtures__/async-config/jest.config.js
@@ -1,3 +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 = async function () {
   return {
     jestConfig: 'async-config',
diff --git a/packages/jest-config/src/__fixtures__/js-config/jest.config.js b/packages/jest-config/src/__fixtures__/js-config/jest.config.js
index ca94a9b4d2f6..40ef4689be89 100644
--- a/packages/jest-config/src/__fixtures__/js-config/jest.config.js
+++ b/packages/jest-config/src/__fixtures__/js-config/jest.config.js
@@ -1,3 +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 = {
   jestConfig: 'jest.config.js',
 };
diff --git a/packages/jest-config/src/__fixtures__/multiple-config-files/jest.config.js b/packages/jest-config/src/__fixtures__/multiple-config-files/jest.config.js
index ca94a9b4d2f6..40ef4689be89 100644
--- a/packages/jest-config/src/__fixtures__/multiple-config-files/jest.config.js
+++ b/packages/jest-config/src/__fixtures__/multiple-config-files/jest.config.js
@@ -1,3 +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 = {
   jestConfig: 'jest.config.js',
 };
diff --git a/packages/jest-config/src/__fixtures__/ts-config/jest.config.ts b/packages/jest-config/src/__fixtures__/ts-config/jest.config.ts
index 64d592d87ceb..bf05ee62de87 100644
--- a/packages/jest-config/src/__fixtures__/ts-config/jest.config.ts
+++ b/packages/jest-config/src/__fixtures__/ts-config/jest.config.ts
@@ -1,3 +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.
+ */
 export default {
   jestConfig: 'jest.config.ts',
 };
diff --git a/packages/jest-config/src/__tests__/readInitialOptions.test.ts b/packages/jest-config/src/__tests__/readInitialOptions.test.ts
index d16512e9b763..5d5e666f026e 100644
--- a/packages/jest-config/src/__tests__/readInitialOptions.test.ts
+++ b/packages/jest-config/src/__tests__/readInitialOptions.test.ts
@@ -1,3 +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.
+ */
 import path = require('path');
 import type {Config} from 'jest-runner';
 import {readInitialOptions} from '../index';

From d93a12c47478319a95a203208749b82749fdebf0 Mon Sep 17 00:00:00 2001
From: Nico Jansen <jansennico@gmail.com>
Date: Sun, 2 Oct 2022 13:53:21 +0200
Subject: [PATCH 05/24] Update assert: also use forward slashes on windows.

---
 .../jest-config/src/__tests__/readInitialOptions.test.ts  | 8 ++------
 1 file changed, 2 insertions(+), 6 deletions(-)

diff --git a/packages/jest-config/src/__tests__/readInitialOptions.test.ts b/packages/jest-config/src/__tests__/readInitialOptions.test.ts
index 5d5e666f026e..caa06adb6f29 100644
--- a/packages/jest-config/src/__tests__/readInitialOptions.test.ts
+++ b/packages/jest-config/src/__tests__/readInitialOptions.test.ts
@@ -99,12 +99,8 @@ describe(readInitialOptions.name, () => {
     jest.spyOn(process, 'cwd').mockReturnValue(cwd);
     const error: Error = await readInitialOptions().catch(error => error);
     expect(error.message).toContain('Multiple configurations found');
-    expect(error.message).toContain(
-      resolveFixture('multiple-config-files', 'jest.config.js'),
-    );
-    expect(error.message).toContain(
-      resolveFixture('multiple-config-files', 'jest.config.json'),
-    );
+    expect(error.message).toContain('multiple-config-files/jest.config.js');
+    expect(error.message).toContain('multiple-config-files/jest.config.json');
   });
 
   test('should be able to ignore multiple config files error', async () => {

From eadd24e314de34f13a6f2e533f0033940aaeb3b8 Mon Sep 17 00:00:00 2001
From: Nico Jansen <jansennico@gmail.com>
Date: Sun, 2 Oct 2022 13:56:55 +0200
Subject: [PATCH 06/24] Update packages/jest-config/src/index.ts

Co-authored-by: Simen Bekkhus <sbekkhus91@gmail.com>
---
 packages/jest-config/src/index.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/packages/jest-config/src/index.ts b/packages/jest-config/src/index.ts
index 14626084aed9..a74da0f2b508 100644
--- a/packages/jest-config/src/index.ts
+++ b/packages/jest-config/src/index.ts
@@ -258,7 +258,7 @@ export async function readInitialOptions(
      * When true, jest will read try to read config from the current working directory.
      * (default is false)
      */
-    readFromCwdInstead?: boolean;
+    readFromCwd?: boolean;
     /**
      * Indicates whether or not to ignore the error of jest finding multiple config files.
      * (default is false)

From 947bfaa10d618657055c9d84e06bb686752ce054 Mon Sep 17 00:00:00 2001
From: Nico Jansen <jansennico@gmail.com>
Date: Sun, 2 Oct 2022 14:00:35 +0200
Subject: [PATCH 07/24] Update changelog sorting

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

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 91c521c46c17..d74de77d36f6 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,9 +2,9 @@
 
 ### Features
 
+- `[jest-config]` Add `readInitialConfig` utility function ([#13356](https://github.com/facebook/jest/pull/13356))
 - `[jest-core]` Enable testResultsProcessor to be async ([#13343](https://github.com/facebook/jest/pull/13343))
 - `[expect, @jest/expect-utils]` Allow `isA` utility to take a type argument ([#13355](https://github.com/facebook/jest/pull/13355))
-- `[jest-config]` Add `readInitialConfig` utility function ([#13356](https://github.com/facebook/jest/pull/13356))
 
 ### Fixes
 

From 7793ff2ef5b4f5e61d76ab5efbb84d50f4b658ec Mon Sep 17 00:00:00 2001
From: Nico Jansen <jansennico@gmail.com>
Date: Sun, 2 Oct 2022 14:04:27 +0200
Subject: [PATCH 08/24] Move integration tests to e2e

---
 e2e/__tests__/readInitialOptions.test.ts      | 101 ++++++++++++++++++
 .../async-config/jest.config.js               |   0
 .../js-config/jest.config.js                  |   0
 .../json-config/jest.config.json              |   0
 .../multiple-config-files/jest.config.js      |   0
 .../multiple-config-files/jest.config.json    |   0
 .../pkg-config/package.json                   |   0
 .../ts-config/jest.config.ts                  |   0
 .../src/__tests__/readInitialOptions.test.ts  |  92 +---------------
 9 files changed, 102 insertions(+), 91 deletions(-)
 create mode 100644 e2e/__tests__/readInitialOptions.test.ts
 rename {packages/jest-config/src/__fixtures__ => e2e/read-initial-options}/async-config/jest.config.js (100%)
 rename {packages/jest-config/src/__fixtures__ => e2e/read-initial-options}/js-config/jest.config.js (100%)
 rename {packages/jest-config/src/__fixtures__ => e2e/read-initial-options}/json-config/jest.config.json (100%)
 rename {packages/jest-config/src/__fixtures__ => e2e/read-initial-options}/multiple-config-files/jest.config.js (100%)
 rename {packages/jest-config/src/__fixtures__ => e2e/read-initial-options}/multiple-config-files/jest.config.json (100%)
 rename {packages/jest-config/src/__fixtures__ => e2e/read-initial-options}/pkg-config/package.json (100%)
 rename {packages/jest-config/src/__fixtures__ => e2e/read-initial-options}/ts-config/jest.config.ts (100%)

diff --git a/e2e/__tests__/readInitialOptions.test.ts b/e2e/__tests__/readInitialOptions.test.ts
new file mode 100644
index 000000000000..60254a719dac
--- /dev/null
+++ b/e2e/__tests__/readInitialOptions.test.ts
@@ -0,0 +1,101 @@
+/**
+ * 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 = require('path');
+import {readInitialOptions} from 'jest-config';
+
+function resolveFixture(...pathSegments: Array<string>) {
+  return path.resolve(__dirname, '..', 'read-initial-options', ...pathSegments);
+}
+
+describe(readInitialOptions.name, () => {
+  test('should read from the cwd by default', async () => {
+    const configFile = resolveFixture('js-config', 'jest.config.js');
+    const rootDir = resolveFixture('js-config');
+    jest.spyOn(process, 'cwd').mockReturnValue(rootDir);
+    const {config, configPath} = await readInitialOptions();
+    expect(config).toEqual({jestConfig: 'jest.config.js', rootDir});
+    expect(configPath).toEqual(configFile);
+  });
+  test('should read a jest.config.js file', async () => {
+    const configFile = resolveFixture('js-config', 'jest.config.js');
+    const rootDir = resolveFixture('js-config');
+    const {config, configPath} = await readInitialOptions(configFile);
+    expect(config).toEqual({jestConfig: 'jest.config.js', rootDir});
+    expect(configPath).toEqual(configFile);
+  });
+  test('should read a package.json file', async () => {
+    const configFile = resolveFixture('pkg-config', 'package.json');
+    const rootDir = resolveFixture('pkg-config');
+    const {config, configPath} = await readInitialOptions(configFile);
+    expect(config).toEqual({jestConfig: 'package.json', rootDir});
+    expect(configPath).toEqual(configFile);
+  });
+  test('should read a jest.config.ts file', async () => {
+    const configFile = resolveFixture('ts-config', 'jest.config.ts');
+    const rootDir = resolveFixture('ts-config');
+    const {config, configPath} = await readInitialOptions(configFile);
+    expect(config).toEqual({jestConfig: 'jest.config.ts', rootDir});
+    expect(configPath).toEqual(configFile);
+  });
+  test('should read a jest.config.json file', async () => {
+    const configFile = resolveFixture('json-config', 'jest.config.json');
+    const rootDir = resolveFixture('json-config');
+    const {config, configPath} = await readInitialOptions(configFile);
+    expect(config).toEqual({jestConfig: 'jest.config.json', rootDir});
+    expect(configPath).toEqual(configFile);
+  });
+  test('should read a jest config exporting an async function', async () => {
+    const configFile = resolveFixture('async-config', 'jest.config.js');
+    const rootDir = resolveFixture('async-config');
+    const {config, configPath} = await readInitialOptions(configFile);
+    expect(config).toEqual({jestConfig: 'async-config', rootDir});
+    expect(configPath).toEqual(configFile);
+  });
+
+  test('should be able to skip config reading, instead read from cwd', async () => {
+    const expectedConfigFile = resolveFixture(
+      'json-config',
+      'jest.config.json',
+    );
+    jest.spyOn(process, 'cwd').mockReturnValue(resolveFixture('json-config'));
+    const {config, configPath} = await readInitialOptions(
+      resolveFixture('js-config', 'jest.config.js'),
+      {
+        readFromCwdInstead: true,
+      },
+    );
+    expect(config).toEqual({
+      jestConfig: 'jest.config.json',
+      rootDir: path.dirname(expectedConfigFile),
+    });
+    expect(configPath).toEqual(expectedConfigFile);
+  });
+
+  test('should give an error when there are multiple config files', async () => {
+    const cwd = resolveFixture('multiple-config-files');
+    jest.spyOn(process, 'cwd').mockReturnValue(cwd);
+    const error: Error = await readInitialOptions().catch(error => error);
+    expect(error.message).toContain('Multiple configurations found');
+    expect(error.message).toContain('multiple-config-files/jest.config.js');
+    expect(error.message).toContain('multiple-config-files/jest.config.json');
+  });
+
+  test('should be able to ignore multiple config files error', async () => {
+    const cwd = resolveFixture('multiple-config-files');
+    jest.spyOn(process, 'cwd').mockReturnValue(cwd);
+    const {config, configPath} = await readInitialOptions(undefined, {
+      skipMultipleConfigError: true,
+    });
+    expect(config).toEqual({
+      jestConfig: 'jest.config.js',
+      rootDir: resolveFixture('multiple-config-files'),
+    });
+    expect(configPath).toEqual(
+      resolveFixture('multiple-config-files', 'jest.config.js'),
+    );
+  });
+});
diff --git a/packages/jest-config/src/__fixtures__/async-config/jest.config.js b/e2e/read-initial-options/async-config/jest.config.js
similarity index 100%
rename from packages/jest-config/src/__fixtures__/async-config/jest.config.js
rename to e2e/read-initial-options/async-config/jest.config.js
diff --git a/packages/jest-config/src/__fixtures__/js-config/jest.config.js b/e2e/read-initial-options/js-config/jest.config.js
similarity index 100%
rename from packages/jest-config/src/__fixtures__/js-config/jest.config.js
rename to e2e/read-initial-options/js-config/jest.config.js
diff --git a/packages/jest-config/src/__fixtures__/json-config/jest.config.json b/e2e/read-initial-options/json-config/jest.config.json
similarity index 100%
rename from packages/jest-config/src/__fixtures__/json-config/jest.config.json
rename to e2e/read-initial-options/json-config/jest.config.json
diff --git a/packages/jest-config/src/__fixtures__/multiple-config-files/jest.config.js b/e2e/read-initial-options/multiple-config-files/jest.config.js
similarity index 100%
rename from packages/jest-config/src/__fixtures__/multiple-config-files/jest.config.js
rename to e2e/read-initial-options/multiple-config-files/jest.config.js
diff --git a/packages/jest-config/src/__fixtures__/multiple-config-files/jest.config.json b/e2e/read-initial-options/multiple-config-files/jest.config.json
similarity index 100%
rename from packages/jest-config/src/__fixtures__/multiple-config-files/jest.config.json
rename to e2e/read-initial-options/multiple-config-files/jest.config.json
diff --git a/packages/jest-config/src/__fixtures__/pkg-config/package.json b/e2e/read-initial-options/pkg-config/package.json
similarity index 100%
rename from packages/jest-config/src/__fixtures__/pkg-config/package.json
rename to e2e/read-initial-options/pkg-config/package.json
diff --git a/packages/jest-config/src/__fixtures__/ts-config/jest.config.ts b/e2e/read-initial-options/ts-config/jest.config.ts
similarity index 100%
rename from packages/jest-config/src/__fixtures__/ts-config/jest.config.ts
rename to e2e/read-initial-options/ts-config/jest.config.ts
diff --git a/packages/jest-config/src/__tests__/readInitialOptions.test.ts b/packages/jest-config/src/__tests__/readInitialOptions.test.ts
index caa06adb6f29..4feb9c2a6154 100644
--- a/packages/jest-config/src/__tests__/readInitialOptions.test.ts
+++ b/packages/jest-config/src/__tests__/readInitialOptions.test.ts
@@ -4,58 +4,10 @@
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
  */
-import path = require('path');
 import type {Config} from 'jest-runner';
 import {readInitialOptions} from '../index';
 
-function resolveFixture(...pathSegments: Array<string>) {
-  return path.resolve(__dirname, '..', '__fixtures__', ...pathSegments);
-}
-
 describe(readInitialOptions.name, () => {
-  test('should read from the cwd by default', async () => {
-    const configFile = resolveFixture('js-config', 'jest.config.js');
-    const rootDir = resolveFixture('js-config');
-    jest.spyOn(process, 'cwd').mockReturnValue(rootDir);
-    const {config, configPath} = await readInitialOptions();
-    expect(config).toEqual({jestConfig: 'jest.config.js', rootDir});
-    expect(configPath).toEqual(configFile);
-  });
-  test('should read a jest.config.js file', async () => {
-    const configFile = resolveFixture('js-config', 'jest.config.js');
-    const rootDir = resolveFixture('js-config');
-    const {config, configPath} = await readInitialOptions(configFile);
-    expect(config).toEqual({jestConfig: 'jest.config.js', rootDir});
-    expect(configPath).toEqual(configFile);
-  });
-  test('should read a package.json file', async () => {
-    const configFile = resolveFixture('pkg-config', 'package.json');
-    const rootDir = resolveFixture('pkg-config');
-    const {config, configPath} = await readInitialOptions(configFile);
-    expect(config).toEqual({jestConfig: 'package.json', rootDir});
-    expect(configPath).toEqual(configFile);
-  });
-  test('should read a jest.config.ts file', async () => {
-    const configFile = resolveFixture('ts-config', 'jest.config.ts');
-    const rootDir = resolveFixture('ts-config');
-    const {config, configPath} = await readInitialOptions(configFile);
-    expect(config).toEqual({jestConfig: 'jest.config.ts', rootDir});
-    expect(configPath).toEqual(configFile);
-  });
-  test('should read a jest.config.json file', async () => {
-    const configFile = resolveFixture('json-config', 'jest.config.json');
-    const rootDir = resolveFixture('json-config');
-    const {config, configPath} = await readInitialOptions(configFile);
-    expect(config).toEqual({jestConfig: 'jest.config.json', rootDir});
-    expect(configPath).toEqual(configFile);
-  });
-  test('should read a jest config exporting an async function', async () => {
-    const configFile = resolveFixture('async-config', 'jest.config.js');
-    const rootDir = resolveFixture('async-config');
-    const {config, configPath} = await readInitialOptions(configFile);
-    expect(config).toEqual({jestConfig: 'async-config', rootDir});
-    expect(configPath).toEqual(configFile);
-  });
   test('should be able to use serialized jest config', async () => {
     const inputConfig = {jestConfig: 'serialized'};
     const {config, configPath} = await readInitialOptions(
@@ -74,47 +26,5 @@ describe(readInitialOptions.name, () => {
     expect(config).toEqual({...inputConfig, rootDir: process.cwd()});
     expect(configPath).toEqual(null);
   });
-
-  test('should be able to skip config reading, instead read from cwd', async () => {
-    const expectedConfigFile = resolveFixture(
-      'json-config',
-      'jest.config.json',
-    );
-    jest.spyOn(process, 'cwd').mockReturnValue(resolveFixture('json-config'));
-    const {config, configPath} = await readInitialOptions(
-      resolveFixture('js-config', 'jest.config.js'),
-      {
-        readFromCwdInstead: true,
-      },
-    );
-    expect(config).toEqual({
-      jestConfig: 'jest.config.json',
-      rootDir: path.dirname(expectedConfigFile),
-    });
-    expect(configPath).toEqual(expectedConfigFile);
-  });
-
-  test('should give an error when there are multiple config files', async () => {
-    const cwd = resolveFixture('multiple-config-files');
-    jest.spyOn(process, 'cwd').mockReturnValue(cwd);
-    const error: Error = await readInitialOptions().catch(error => error);
-    expect(error.message).toContain('Multiple configurations found');
-    expect(error.message).toContain('multiple-config-files/jest.config.js');
-    expect(error.message).toContain('multiple-config-files/jest.config.json');
-  });
-
-  test('should be able to ignore multiple config files error', async () => {
-    const cwd = resolveFixture('multiple-config-files');
-    jest.spyOn(process, 'cwd').mockReturnValue(cwd);
-    const {config, configPath} = await readInitialOptions(undefined, {
-      skipMultipleConfigError: true,
-    });
-    expect(config).toEqual({
-      jestConfig: 'jest.config.js',
-      rootDir: resolveFixture('multiple-config-files'),
-    });
-    expect(configPath).toEqual(
-      resolveFixture('multiple-config-files', 'jest.config.js'),
-    );
-  });
+  // Note: actual file reading is tested in e2e test
 });

From 153af9b8f643e5a41a44546e2ae193bb2c33b71d Mon Sep 17 00:00:00 2001
From: Nico Jansen <jansennico@gmail.com>
Date: Sun, 2 Oct 2022 14:04:48 +0200
Subject: [PATCH 09/24] Remove `--experimental-vm-modules`

---
 .vscode/launch.json | 3 ---
 package.json        | 2 +-
 2 files changed, 1 insertion(+), 4 deletions(-)

diff --git a/.vscode/launch.json b/.vscode/launch.json
index 8802afcba97c..5de4feacd272 100644
--- a/.vscode/launch.json
+++ b/.vscode/launch.json
@@ -13,9 +13,6 @@
       "console": "integratedTerminal",
       "internalConsoleOptions": "neverOpen",
       "disableOptimisticBPs": true,
-      "env": {
-        "NODE_OPTIONS": "--experimental-vm-modules"
-      },
       "windows": {
         "program": "${workspaceFolder}/node_modules/jest/bin/jest"
       }
diff --git a/package.json b/package.json
index 09110bd7b714..425b52667541 100644
--- a/package.json
+++ b/package.json
@@ -95,7 +95,7 @@
     "clean-e2e": "node ./scripts/cleanE2e.mjs",
     "crowdin:upload": "echo 'Uploading sources to Crowdin' && crowdin upload sources --config ./crowdin.yaml",
     "crowdin:download": "echo 'Downloading translations from Crowdin' && crowdin download --config ./crowdin.yaml",
-    "jest": "node --experimental-vm-modules ./packages/jest-cli/bin/jest.js",
+    "jest": "node ./packages/jest-cli/bin/jest.js",
     "jest-jasmine": "JEST_JASMINE=1 yarn jest",
     "jest-jasmine-ci": "yarn jest-jasmine --color --config jest.config.ci.mjs",
     "jest-coverage": "yarn jest --coverage",

From 4294610a453525d5ad11f5f36e5f4cac72c4fd81 Mon Sep 17 00:00:00 2001
From: Nico Jansen <jansennico@gmail.com>
Date: Sun, 2 Oct 2022 14:10:54 +0200
Subject: [PATCH 10/24] Extract `ReadJestConfigOptions` interface

---
 packages/jest-config/src/index.ts | 51 ++++++++++++++++---------------
 1 file changed, 26 insertions(+), 25 deletions(-)

diff --git a/packages/jest-config/src/index.ts b/packages/jest-config/src/index.ts
index a74da0f2b508..788ce5d63caa 100644
--- a/packages/jest-config/src/index.ts
+++ b/packages/jest-config/src/index.ts
@@ -229,7 +229,29 @@ This usually means that your ${chalk.bold(
   }
 };
 
-/**
+export interface ReadJestConfigOptions {
+  /**
+   * The package root or deserialized config (default is cwd)
+   */
+  packageRootOrConfig?: string | Config.InitialOptions;
+  /**
+   * When the `packageRootOrConfig` contains config, this parameter should
+   * contain the dirname of the parent config
+   */
+  parentConfigDirname?: null | string;
+  /**
+   * Indicates whether or not to read the specified config file from disk.
+   * When true, jest will read try to read config from the current working directory.
+   * (default is false)
+   */
+  readFromCwd?: boolean;
+  /**
+   * Indicates whether or not to ignore the error of jest finding multiple config files.
+   * (default is false)
+   */
+  skipMultipleConfigError?: boolean;
+}
+
 /**
  * Reads the jest config, without validating them or filling it out with defaults.
  * @param config The path to the file or serialized config.
@@ -241,30 +263,9 @@ export async function readInitialOptions(
   {
     packageRootOrConfig = process.cwd(),
     parentConfigDirname = null,
-    readFromCwdInstead = false,
+    readFromCwd = false,
     skipMultipleConfigError = false,
-  }: {
-    /**
-     * The package root or deserialized config (default is cwd)
-     */
-    packageRootOrConfig?: string | Config.InitialOptions;
-    /**
-     * When the `packageRootOrConfig` contains config, this parameter should
-     * contain the dirname of the parent config
-     */
-    parentConfigDirname?: null | string;
-    /**
-     * Indicates whether or not to read the specified config file from disk.
-     * When true, jest will read try to read config from the current working directory.
-     * (default is false)
-     */
-    readFromCwd?: boolean;
-    /**
-     * Indicates whether or not to ignore the error of jest finding multiple config files.
-     * (default is false)
-     */
-    skipMultipleConfigError?: boolean;
-  } = {},
+  }: ReadJestConfigOptions = {},
 ): Promise<{config: Config.InitialOptions; configPath: string | null}> {
   if (typeof packageRootOrConfig !== 'string') {
     if (parentConfigDirname) {
@@ -295,7 +296,7 @@ export async function readInitialOptions(
     return {config: initialOptions, configPath: null};
     // A string passed to `--config`, which is either a direct path to the config
     // or a path to directory containing `package.json`, `jest.config.js` or `jest.config.ts`
-  } else if (!readFromCwdInstead && typeof config == 'string') {
+  } else if (!readFromCwd && typeof config == 'string') {
     const configPath = resolveConfigPath(
       config,
       process.cwd(),

From 6d347a67bc46e23da362e99dd9b5d79e2bfa180e Mon Sep 17 00:00:00 2001
From: Nico Jansen <jansennico@gmail.com>
Date: Sun, 2 Oct 2022 14:18:41 +0200
Subject: [PATCH 11/24] Finish rename `readFromCwdInstead` -> `readFromCwd`

---
 e2e/__tests__/readInitialOptions.test.ts | 2 +-
 packages/jest-config/src/index.ts        | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/e2e/__tests__/readInitialOptions.test.ts b/e2e/__tests__/readInitialOptions.test.ts
index 60254a719dac..f6b0c56f0db0 100644
--- a/e2e/__tests__/readInitialOptions.test.ts
+++ b/e2e/__tests__/readInitialOptions.test.ts
@@ -65,7 +65,7 @@ describe(readInitialOptions.name, () => {
     const {config, configPath} = await readInitialOptions(
       resolveFixture('js-config', 'jest.config.js'),
       {
-        readFromCwdInstead: true,
+        readFromCwd: true,
       },
     );
     expect(config).toEqual({
diff --git a/packages/jest-config/src/index.ts b/packages/jest-config/src/index.ts
index 788ce5d63caa..06613c1b0b96 100644
--- a/packages/jest-config/src/index.ts
+++ b/packages/jest-config/src/index.ts
@@ -48,7 +48,7 @@ export async function readConfig(
     {
       packageRootOrConfig,
       parentConfigDirname,
-      readFromCwdInstead: skipArgvConfigOption,
+      readFromCwd: skipArgvConfigOption,
       skipMultipleConfigError,
     },
   );

From c2dffe995af845ccc0bd4affc936d8013f90bf19 Mon Sep 17 00:00:00 2001
From: Nico Jansen <jansennico@gmail.com>
Date: Sun, 2 Oct 2022 14:25:31 +0200
Subject: [PATCH 12/24] Import from `@jest/types` instead of `jest-runner`

Co-authored-by: Tom Mrazauskas <tom@mrazauskas.de>
---
 packages/jest-config/src/__tests__/readInitialOptions.test.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/packages/jest-config/src/__tests__/readInitialOptions.test.ts b/packages/jest-config/src/__tests__/readInitialOptions.test.ts
index 4feb9c2a6154..3bd94b176e92 100644
--- a/packages/jest-config/src/__tests__/readInitialOptions.test.ts
+++ b/packages/jest-config/src/__tests__/readInitialOptions.test.ts
@@ -4,7 +4,7 @@
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
  */
-import type {Config} from 'jest-runner';
+import type {Config} from '@jest/types';
 import {readInitialOptions} from '../index';
 
 describe(readInitialOptions.name, () => {

From b3a13cc62f597c4390d1ea5c83a79e4ec46f366a Mon Sep 17 00:00:00 2001
From: Nico Jansen <jansennico@gmail.com>
Date: Sun, 2 Oct 2022 15:23:21 +0200
Subject: [PATCH 13/24] Update
 packages/jest-config/src/__tests__/readInitialOptions.test.ts

Co-authored-by: Tom Mrazauskas <tom@mrazauskas.de>
---
 packages/jest-config/src/__tests__/readInitialOptions.test.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/packages/jest-config/src/__tests__/readInitialOptions.test.ts b/packages/jest-config/src/__tests__/readInitialOptions.test.ts
index 3bd94b176e92..de85b0500b0d 100644
--- a/packages/jest-config/src/__tests__/readInitialOptions.test.ts
+++ b/packages/jest-config/src/__tests__/readInitialOptions.test.ts
@@ -24,7 +24,7 @@ describe(readInitialOptions.name, () => {
       parentConfigDirname: process.cwd(),
     });
     expect(config).toEqual({...inputConfig, rootDir: process.cwd()});
-    expect(configPath).toEqual(null);
+    expect(configPath).toBeNull();
   });
   // Note: actual file reading is tested in e2e test
 });

From c41dbdff20b200f548fca92d5fffc199a6f5c9e7 Mon Sep 17 00:00:00 2001
From: Nico Jansen <jansennico@gmail.com>
Date: Sun, 2 Oct 2022 15:25:01 +0200
Subject: [PATCH 14/24] Update
 packages/jest-config/src/__tests__/readInitialOptions.test.ts

Co-authored-by: Tom Mrazauskas <tom@mrazauskas.de>
---
 packages/jest-config/src/__tests__/readInitialOptions.test.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/packages/jest-config/src/__tests__/readInitialOptions.test.ts b/packages/jest-config/src/__tests__/readInitialOptions.test.ts
index de85b0500b0d..dcf57a3d912e 100644
--- a/packages/jest-config/src/__tests__/readInitialOptions.test.ts
+++ b/packages/jest-config/src/__tests__/readInitialOptions.test.ts
@@ -14,7 +14,7 @@ describe(readInitialOptions.name, () => {
       JSON.stringify(inputConfig),
     );
     expect(config).toEqual({...inputConfig, rootDir: process.cwd()});
-    expect(configPath).toEqual(null);
+    expect(configPath).toBeNull();
   });
 
   test('should allow deserialized options', async () => {

From 8b479f57b8e37adc0afaa32c8fc80d5dffca3e1b Mon Sep 17 00:00:00 2001
From: Nico Jansen <jansennico@gmail.com>
Date: Sun, 2 Oct 2022 15:25:20 +0200
Subject: [PATCH 15/24] Update
 packages/jest-config/src/__tests__/readInitialOptions.test.ts

Co-authored-by: Tom Mrazauskas <tom@mrazauskas.de>
---
 packages/jest-config/src/__tests__/readInitialOptions.test.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/packages/jest-config/src/__tests__/readInitialOptions.test.ts b/packages/jest-config/src/__tests__/readInitialOptions.test.ts
index dcf57a3d912e..4b1038275b6d 100644
--- a/packages/jest-config/src/__tests__/readInitialOptions.test.ts
+++ b/packages/jest-config/src/__tests__/readInitialOptions.test.ts
@@ -7,7 +7,7 @@
 import type {Config} from '@jest/types';
 import {readInitialOptions} from '../index';
 
-describe(readInitialOptions.name, () => {
+describe(readInitialOptions, () => {
   test('should be able to use serialized jest config', async () => {
     const inputConfig = {jestConfig: 'serialized'};
     const {config, configPath} = await readInitialOptions(

From 9f01d80ea694cfec03f3600d89f498238b6a7d12 Mon Sep 17 00:00:00 2001
From: Nico Jansen <jansennico@gmail.com>
Date: Sun, 2 Oct 2022 15:26:06 +0200
Subject: [PATCH 16/24] Remove final `.name`

---
 e2e/__tests__/readInitialOptions.test.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/e2e/__tests__/readInitialOptions.test.ts b/e2e/__tests__/readInitialOptions.test.ts
index f6b0c56f0db0..14aec27367ce 100644
--- a/e2e/__tests__/readInitialOptions.test.ts
+++ b/e2e/__tests__/readInitialOptions.test.ts
@@ -11,7 +11,7 @@ function resolveFixture(...pathSegments: Array<string>) {
   return path.resolve(__dirname, '..', 'read-initial-options', ...pathSegments);
 }
 
-describe(readInitialOptions.name, () => {
+describe(readInitialOptions, () => {
   test('should read from the cwd by default', async () => {
     const configFile = resolveFixture('js-config', 'jest.config.js');
     const rootDir = resolveFixture('js-config');

From 188b0803631a4e93e273e8ea51d2780899a67371 Mon Sep 17 00:00:00 2001
From: Nico Jansen <jansennico@gmail.com>
Date: Mon, 3 Oct 2022 08:24:35 +0200
Subject: [PATCH 17/24] Read config by proxy for ts and mjs files

---
 e2e/__tests__/readInitialOptions.test.ts       | 18 +++++++++++++++++-
 .../mjs-config/jest.config.mjs                 |  9 +++++++++
 e2e/read-initial-options/readOptions.js        |  5 +++++
 3 files changed, 31 insertions(+), 1 deletion(-)
 create mode 100644 e2e/read-initial-options/mjs-config/jest.config.mjs
 create mode 100644 e2e/read-initial-options/readOptions.js

diff --git a/e2e/__tests__/readInitialOptions.test.ts b/e2e/__tests__/readInitialOptions.test.ts
index 14aec27367ce..17408d44ff41 100644
--- a/e2e/__tests__/readInitialOptions.test.ts
+++ b/e2e/__tests__/readInitialOptions.test.ts
@@ -5,6 +5,7 @@
  * LICENSE file in the root directory of this source tree.
  */
 import path = require('path');
+import execa = require('execa');
 import {readInitialOptions} from 'jest-config';
 
 function resolveFixture(...pathSegments: Array<string>) {
@@ -37,10 +38,25 @@ describe(readInitialOptions, () => {
   test('should read a jest.config.ts file', async () => {
     const configFile = resolveFixture('ts-config', 'jest.config.ts');
     const rootDir = resolveFixture('ts-config');
-    const {config, configPath} = await readInitialOptions(configFile);
+    // Read by proxy, because we're running in a VM and are not allowed to import 'ts-node' directly
+    const {stdout} = await execa('node', ['../readOptions.js'], {
+      cwd: rootDir,
+    });
+    const {config, configPath} = JSON.parse(stdout);
     expect(config).toEqual({jestConfig: 'jest.config.ts', rootDir});
     expect(configPath).toEqual(configFile);
   });
+  test('should read a jest.config.mjs file', async () => {
+    const configFile = resolveFixture('mjs-config', 'jest.config.mjs');
+    const rootDir = resolveFixture('mjs-config');
+    // Read by proxy, because we're running in a VM and are not allowed to `import` directly
+    const {stdout} = await execa('node', ['../readOptions.js'], {
+      cwd: rootDir,
+    });
+    const {config, configPath} = JSON.parse(stdout);
+    expect(config).toEqual({jestConfig: 'jest.config.mjs', rootDir});
+    expect(configPath).toEqual(configFile);
+  });
   test('should read a jest.config.json file', async () => {
     const configFile = resolveFixture('json-config', 'jest.config.json');
     const rootDir = resolveFixture('json-config');
diff --git a/e2e/read-initial-options/mjs-config/jest.config.mjs b/e2e/read-initial-options/mjs-config/jest.config.mjs
new file mode 100644
index 000000000000..4875bf59fc0c
--- /dev/null
+++ b/e2e/read-initial-options/mjs-config/jest.config.mjs
@@ -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.
+ */
+export default {
+  jestConfig: 'jest.config.mjs',
+};
diff --git a/e2e/read-initial-options/readOptions.js b/e2e/read-initial-options/readOptions.js
new file mode 100644
index 000000000000..e9338575401e
--- /dev/null
+++ b/e2e/read-initial-options/readOptions.js
@@ -0,0 +1,5 @@
+const {readInitialOptions} = require('jest-config');
+async function readConfig() {
+  console.log(JSON.stringify(await readInitialOptions(process.argv[2])));
+}
+readConfig();

From 5c54a6ae11b464c2a1d152866df403ccd0cc861c Mon Sep 17 00:00:00 2001
From: Nico Jansen <jansennico@gmail.com>
Date: Mon, 3 Oct 2022 08:25:11 +0200
Subject: [PATCH 18/24] Add copyright header

---
 e2e/read-initial-options/readOptions.js | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/e2e/read-initial-options/readOptions.js b/e2e/read-initial-options/readOptions.js
index e9338575401e..76dd5badc0ac 100644
--- a/e2e/read-initial-options/readOptions.js
+++ b/e2e/read-initial-options/readOptions.js
@@ -1,3 +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.
+ */
 const {readInitialOptions} = require('jest-config');
 async function readConfig() {
   console.log(JSON.stringify(await readInitialOptions(process.argv[2])));

From 53b49ba5aa0402ca4b9c8c0ffa8f26f5caabda38 Mon Sep 17 00:00:00 2001
From: Nico Jansen <jansennico@gmail.com>
Date: Mon, 3 Oct 2022 09:55:24 +0200
Subject: [PATCH 19/24] Read by proxy for every test

---
 e2e/__tests__/readInitialOptions.test.ts | 73 +++++++++++++++++-------
 e2e/read-initial-options/readOptions.js  | 15 ++++-
 2 files changed, 66 insertions(+), 22 deletions(-)

diff --git a/e2e/__tests__/readInitialOptions.test.ts b/e2e/__tests__/readInitialOptions.test.ts
index 17408d44ff41..b21da575ec06 100644
--- a/e2e/__tests__/readInitialOptions.test.ts
+++ b/e2e/__tests__/readInitialOptions.test.ts
@@ -6,68 +6,99 @@
  */
 import path = require('path');
 import execa = require('execa');
-import {readInitialOptions} from 'jest-config';
+import type {ReadJestConfigOptions, readInitialOptions} from 'jest-config';
 
 function resolveFixture(...pathSegments: Array<string>) {
   return path.resolve(__dirname, '..', 'read-initial-options', ...pathSegments);
 }
 
-describe(readInitialOptions, () => {
+interface ProxyReadJestConfigOptions extends ReadJestConfigOptions {
+  cwd?: string;
+}
+
+/**
+ * These e2e tests are running via a child process, because we're running in a VM and are not allowed to `import` directly
+ * It also represents a more real-world example of how to run.
+ */
+async function proxyReadInitialOptions(
+  configFile?: string | undefined,
+  options?: ProxyReadJestConfigOptions,
+): ReturnType<typeof readInitialOptions> {
+  const {stdout} = await execa(
+    'node',
+    [
+      require.resolve('../read-initial-options/readOptions.js'),
+      configFile ?? '',
+      JSON.stringify(options),
+    ],
+    {
+      cwd: options?.cwd,
+    },
+  );
+  return JSON.parse(stdout);
+}
+
+describe('readInitialOptions', () => {
   test('should read from the cwd by default', async () => {
     const configFile = resolveFixture('js-config', 'jest.config.js');
     const rootDir = resolveFixture('js-config');
-    jest.spyOn(process, 'cwd').mockReturnValue(rootDir);
-    const {config, configPath} = await readInitialOptions();
+    const {config, configPath} = await proxyReadInitialOptions(undefined, {
+      cwd: rootDir,
+    });
     expect(config).toEqual({jestConfig: 'jest.config.js', rootDir});
     expect(configPath).toEqual(configFile);
   });
   test('should read a jest.config.js file', async () => {
     const configFile = resolveFixture('js-config', 'jest.config.js');
     const rootDir = resolveFixture('js-config');
-    const {config, configPath} = await readInitialOptions(configFile);
+    const {config, configPath} = await proxyReadInitialOptions(undefined, {
+      cwd: rootDir,
+    });
     expect(config).toEqual({jestConfig: 'jest.config.js', rootDir});
     expect(configPath).toEqual(configFile);
   });
   test('should read a package.json file', async () => {
     const configFile = resolveFixture('pkg-config', 'package.json');
     const rootDir = resolveFixture('pkg-config');
-    const {config, configPath} = await readInitialOptions(configFile);
+    const {config, configPath} = await proxyReadInitialOptions(undefined, {
+      cwd: rootDir,
+    });
     expect(config).toEqual({jestConfig: 'package.json', rootDir});
     expect(configPath).toEqual(configFile);
   });
   test('should read a jest.config.ts file', async () => {
     const configFile = resolveFixture('ts-config', 'jest.config.ts');
     const rootDir = resolveFixture('ts-config');
-    // Read by proxy, because we're running in a VM and are not allowed to import 'ts-node' directly
-    const {stdout} = await execa('node', ['../readOptions.js'], {
+    const {config, configPath} = await proxyReadInitialOptions(undefined, {
       cwd: rootDir,
     });
-    const {config, configPath} = JSON.parse(stdout);
     expect(config).toEqual({jestConfig: 'jest.config.ts', rootDir});
     expect(configPath).toEqual(configFile);
   });
   test('should read a jest.config.mjs file', async () => {
     const configFile = resolveFixture('mjs-config', 'jest.config.mjs');
     const rootDir = resolveFixture('mjs-config');
-    // Read by proxy, because we're running in a VM and are not allowed to `import` directly
-    const {stdout} = await execa('node', ['../readOptions.js'], {
+    const {config, configPath} = await proxyReadInitialOptions(undefined, {
       cwd: rootDir,
     });
-    const {config, configPath} = JSON.parse(stdout);
     expect(config).toEqual({jestConfig: 'jest.config.mjs', rootDir});
     expect(configPath).toEqual(configFile);
   });
   test('should read a jest.config.json file', async () => {
     const configFile = resolveFixture('json-config', 'jest.config.json');
     const rootDir = resolveFixture('json-config');
-    const {config, configPath} = await readInitialOptions(configFile);
+    const {config, configPath} = await proxyReadInitialOptions(undefined, {
+      cwd: rootDir,
+    });
     expect(config).toEqual({jestConfig: 'jest.config.json', rootDir});
     expect(configPath).toEqual(configFile);
   });
   test('should read a jest config exporting an async function', async () => {
     const configFile = resolveFixture('async-config', 'jest.config.js');
     const rootDir = resolveFixture('async-config');
-    const {config, configPath} = await readInitialOptions(configFile);
+    const {config, configPath} = await proxyReadInitialOptions(undefined, {
+      cwd: rootDir,
+    });
     expect(config).toEqual({jestConfig: 'async-config', rootDir});
     expect(configPath).toEqual(configFile);
   });
@@ -77,13 +108,14 @@ describe(readInitialOptions, () => {
       'json-config',
       'jest.config.json',
     );
-    jest.spyOn(process, 'cwd').mockReturnValue(resolveFixture('json-config'));
-    const {config, configPath} = await readInitialOptions(
+    const {config, configPath} = await proxyReadInitialOptions(
       resolveFixture('js-config', 'jest.config.js'),
       {
+        cwd: resolveFixture('json-config'),
         readFromCwd: true,
       },
     );
+
     expect(config).toEqual({
       jestConfig: 'jest.config.json',
       rootDir: path.dirname(expectedConfigFile),
@@ -93,8 +125,9 @@ describe(readInitialOptions, () => {
 
   test('should give an error when there are multiple config files', async () => {
     const cwd = resolveFixture('multiple-config-files');
-    jest.spyOn(process, 'cwd').mockReturnValue(cwd);
-    const error: Error = await readInitialOptions().catch(error => error);
+    const error: Error = await proxyReadInitialOptions(undefined, {cwd}).catch(
+      error => error,
+    );
     expect(error.message).toContain('Multiple configurations found');
     expect(error.message).toContain('multiple-config-files/jest.config.js');
     expect(error.message).toContain('multiple-config-files/jest.config.json');
@@ -102,8 +135,8 @@ describe(readInitialOptions, () => {
 
   test('should be able to ignore multiple config files error', async () => {
     const cwd = resolveFixture('multiple-config-files');
-    jest.spyOn(process, 'cwd').mockReturnValue(cwd);
-    const {config, configPath} = await readInitialOptions(undefined, {
+    const {config, configPath} = await proxyReadInitialOptions(undefined, {
+      cwd,
       skipMultipleConfigError: true,
     });
     expect(config).toEqual({
diff --git a/e2e/read-initial-options/readOptions.js b/e2e/read-initial-options/readOptions.js
index 76dd5badc0ac..4bcc661dc079 100644
--- a/e2e/read-initial-options/readOptions.js
+++ b/e2e/read-initial-options/readOptions.js
@@ -6,6 +6,17 @@
  */
 const {readInitialOptions} = require('jest-config');
 async function readConfig() {
-  console.log(JSON.stringify(await readInitialOptions(process.argv[2])));
+  let config = process.argv[2];
+  let options = undefined;
+  if (config === '') {
+    config = undefined;
+  }
+  if (process.argv[3]) {
+    options = JSON.parse(process.argv[3]);
+  }
+  console.log(JSON.stringify(await readInitialOptions(config, options)));
 }
-readConfig();
+readConfig().catch(err => {
+  console.error(err);
+  process.exitCode = 1;
+});

From 34e1a32010d89dda9d96d348b27436638fd55bd2 Mon Sep 17 00:00:00 2001
From: Nico Jansen <jansennico@gmail.com>
Date: Mon, 3 Oct 2022 10:22:10 +0200
Subject: [PATCH 20/24] Update e2e/__tests__/readInitialOptions.test.ts

Co-authored-by: Simen Bekkhus <sbekkhus91@gmail.com>
---
 e2e/__tests__/readInitialOptions.test.ts | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/e2e/__tests__/readInitialOptions.test.ts b/e2e/__tests__/readInitialOptions.test.ts
index b21da575ec06..1ad21a5994f8 100644
--- a/e2e/__tests__/readInitialOptions.test.ts
+++ b/e2e/__tests__/readInitialOptions.test.ts
@@ -31,9 +31,7 @@ async function proxyReadInitialOptions(
       configFile ?? '',
       JSON.stringify(options),
     ],
-    {
-      cwd: options?.cwd,
-    },
+    {cwd: options?.cwd},
   );
   return JSON.parse(stdout);
 }

From 3cf1f21187c64020031727fdd2600f4eb33db6b1 Mon Sep 17 00:00:00 2001
From: Nico Jansen <jansennico@gmail.com>
Date: Mon, 3 Oct 2022 10:24:55 +0200
Subject: [PATCH 21/24] Refactor if/else -> if

---
 packages/jest-config/src/index.ts | 21 +++++++++++----------
 1 file changed, 11 insertions(+), 10 deletions(-)

diff --git a/packages/jest-config/src/index.ts b/packages/jest-config/src/index.ts
index 06613c1b0b96..9058f9f8b520 100644
--- a/packages/jest-config/src/index.ts
+++ b/packages/jest-config/src/index.ts
@@ -279,7 +279,8 @@ export async function readInitialOptions(
         'Jest: Cannot use configuration as an object without a file path.',
       );
     }
-  } else if (isJSONString(config)) {
+  }
+  if (isJSONString(config)) {
     // A JSON string was passed to `--config` argument and we can parse it
     // and use as is.
     let initialOptions;
@@ -296,22 +297,22 @@ export async function readInitialOptions(
     return {config: initialOptions, configPath: null};
     // A string passed to `--config`, which is either a direct path to the config
     // or a path to directory containing `package.json`, `jest.config.js` or `jest.config.ts`
-  } else if (!readFromCwd && typeof config == 'string') {
+  }
+  if (!readFromCwd && typeof config == 'string') {
     const configPath = resolveConfigPath(
       config,
       process.cwd(),
       skipMultipleConfigError,
     );
     return {config: await readConfigFileAndSetRootDir(configPath), configPath};
-  } else {
-    // Otherwise just try to find config in the current rootDir.
-    const configPath = resolveConfigPath(
-      packageRootOrConfig,
-      process.cwd(),
-      skipMultipleConfigError,
-    );
-    return {config: await readConfigFileAndSetRootDir(configPath), configPath};
   }
+  // Otherwise just try to find config in the current rootDir.
+  const configPath = resolveConfigPath(
+    packageRootOrConfig,
+    process.cwd(),
+    skipMultipleConfigError,
+  );
+  return {config: await readConfigFileAndSetRootDir(configPath), configPath};
 }
 
 // Possible scenarios:

From 3d535ba28e698c59db60d61c8c48eeb6ca246f93 Mon Sep 17 00:00:00 2001
From: Nico Jansen <jansennico@gmail.com>
Date: Mon, 3 Oct 2022 13:28:06 +0200
Subject: [PATCH 22/24] refactor: move some comments around

---
 packages/jest-config/src/index.ts | 18 ++++++++----------
 1 file changed, 8 insertions(+), 10 deletions(-)

diff --git a/packages/jest-config/src/index.ts b/packages/jest-config/src/index.ts
index 9058f9f8b520..2fd7a3755723 100644
--- a/packages/jest-config/src/index.ts
+++ b/packages/jest-config/src/index.ts
@@ -281,24 +281,22 @@ export async function readInitialOptions(
     }
   }
   if (isJSONString(config)) {
-    // A JSON string was passed to `--config` argument and we can parse it
-    // and use as is.
-    let initialOptions;
     try {
-      initialOptions = JSON.parse(config);
+      // A JSON string was passed to `--config` argument and we can parse it
+      // and use as is.
+      const initialOptions = JSON.parse(config);
+      // NOTE: we might need to resolve this dir to an absolute path in the future
+      initialOptions.rootDir = initialOptions.rootDir || packageRootOrConfig;
+      return {config: initialOptions, configPath: null};
     } catch {
       throw new Error(
         'There was an error while parsing the `--config` argument as a JSON string.',
       );
     }
-
-    // NOTE: we might need to resolve this dir to an absolute path in the future
-    initialOptions.rootDir = initialOptions.rootDir || packageRootOrConfig;
-    return {config: initialOptions, configPath: null};
-    // A string passed to `--config`, which is either a direct path to the config
-    // or a path to directory containing `package.json`, `jest.config.js` or `jest.config.ts`
   }
   if (!readFromCwd && typeof config == 'string') {
+    // A string passed to `--config`, which is either a direct path to the config
+    // or a path to directory containing `package.json`, `jest.config.js` or `jest.config.ts`
     const configPath = resolveConfigPath(
       config,
       process.cwd(),

From 5ab7237212bb2684a72841f6c21d983d23f5bcfb Mon Sep 17 00:00:00 2001
From: Nico Jansen <jansennico@gmail.com>
Date: Mon, 3 Oct 2022 13:29:10 +0200
Subject: [PATCH 23/24] Update e2e/__tests__/readInitialOptions.test.ts

Co-authored-by: Simen Bekkhus <sbekkhus91@gmail.com>
---
 e2e/__tests__/readInitialOptions.test.ts | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/e2e/__tests__/readInitialOptions.test.ts b/e2e/__tests__/readInitialOptions.test.ts
index 1ad21a5994f8..9d2ba417eb4f 100644
--- a/e2e/__tests__/readInitialOptions.test.ts
+++ b/e2e/__tests__/readInitialOptions.test.ts
@@ -21,8 +21,8 @@ interface ProxyReadJestConfigOptions extends ReadJestConfigOptions {
  * It also represents a more real-world example of how to run.
  */
 async function proxyReadInitialOptions(
-  configFile?: string | undefined,
-  options?: ProxyReadJestConfigOptions,
+  configFile: string | undefined,
+  options: ProxyReadJestConfigOptions,
 ): ReturnType<typeof readInitialOptions> {
   const {stdout} = await execa(
     'node',

From 2dfe6ef5fc1325ef14f183c3c4737eca3a402b5f Mon Sep 17 00:00:00 2001
From: Nico Jansen <jansennico@gmail.com>
Date: Mon, 3 Oct 2022 13:32:25 +0200
Subject: [PATCH 24/24] Require argv to be supplied

---
 packages/jest-config/src/__tests__/readConfig.test.ts | 3 +--
 packages/jest-config/src/index.ts                     | 2 +-
 2 files changed, 2 insertions(+), 3 deletions(-)

diff --git a/packages/jest-config/src/__tests__/readConfig.test.ts b/packages/jest-config/src/__tests__/readConfig.test.ts
index 1452e8355171..09cb362ecf49 100644
--- a/packages/jest-config/src/__tests__/readConfig.test.ts
+++ b/packages/jest-config/src/__tests__/readConfig.test.ts
@@ -10,8 +10,7 @@ import {readConfig} from '../index';
 test('readConfig() throws when an object is passed without a file path', async () => {
   await expect(
     readConfig(
-      // @ts-expect-error
-      null /* argv */,
+      {$0: '', _: []},
       {} /* packageRootOrConfig */,
       false /* skipArgvConfigOption */,
       null /* parentConfigPath */,
diff --git a/packages/jest-config/src/index.ts b/packages/jest-config/src/index.ts
index 2fd7a3755723..f8fb20d3590a 100644
--- a/packages/jest-config/src/index.ts
+++ b/packages/jest-config/src/index.ts
@@ -44,7 +44,7 @@ export async function readConfig(
   skipMultipleConfigError = false,
 ): Promise<ReadConfig> {
   const {config: initialOptions, configPath} = await readInitialOptions(
-    argv?.config,
+    argv.config,
     {
       packageRootOrConfig,
       parentConfigDirname,