From 2fb7aa9bb5cc7b4fcea5319c5573f685fa0c0f57 Mon Sep 17 00:00:00 2001
From: Simen Bekkhus <sbekkhus91@gmail.com>
Date: Tue, 8 Feb 2022 09:32:46 +0100
Subject: [PATCH] chore: ensure all exported files have a consistent filename

---
 CHANGELOG.md                                 |  2 ++
 packages/jest-core/package.json              |  8 ++++----
 packages/jest-core/src/{jest.ts => index.ts} |  0
 packages/jest/package.json                   |  8 ++++----
 packages/jest/src/{jest.ts => index.ts}      |  0
 scripts/buildUtils.js                        | 19 +++++++++++++++++++
 6 files changed, 29 insertions(+), 8 deletions(-)
 rename packages/jest-core/src/{jest.ts => index.ts} (100%)
 rename packages/jest/src/{jest.ts => index.ts} (100%)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 88e1df1ab09c..45f215642604 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -7,6 +7,8 @@
 ### Chore & Maintenance
 
 - `[*]` [**BREAKING**] Drop support for Node v10 and v15 and target first LTS `16.13.0` ([#12220](https://github.com/facebook/jest/pull/12220))
+- `[@jest/core]` Use `index.ts` instead of `jest.ts` as main export ([#12329](https://github.com/facebook/jest/pull/12329))
+- `[jest]` Use `index.ts` instead of `jest.ts` as main export ([#12329](https://github.com/facebook/jest/pull/12329))
 
 ### Performance
 
diff --git a/packages/jest-core/package.json b/packages/jest-core/package.json
index 36d372064557..cf37a0bd46c4 100644
--- a/packages/jest-core/package.json
+++ b/packages/jest-core/package.json
@@ -2,12 +2,12 @@
   "name": "@jest/core",
   "description": "Delightful JavaScript Testing.",
   "version": "27.5.1",
-  "main": "./build/jest.js",
-  "types": "./build/jest.d.ts",
+  "main": "./build/index.js",
+  "types": "./build/index.d.ts",
   "exports": {
     ".": {
-      "types": "./build/jest.d.ts",
-      "default": "./build/jest.js"
+      "types": "./build/index.d.ts",
+      "default": "./build/index.js"
     },
     "./package.json": "./package.json"
   },
diff --git a/packages/jest-core/src/jest.ts b/packages/jest-core/src/index.ts
similarity index 100%
rename from packages/jest-core/src/jest.ts
rename to packages/jest-core/src/index.ts
diff --git a/packages/jest/package.json b/packages/jest/package.json
index e03d8287cd05..c3c8b1af8825 100644
--- a/packages/jest/package.json
+++ b/packages/jest/package.json
@@ -2,12 +2,12 @@
   "name": "jest",
   "description": "Delightful JavaScript Testing.",
   "version": "27.5.1",
-  "main": "./build/jest.js",
-  "types": "./build/jest.d.ts",
+  "main": "./build/index.js",
+  "types": "./build/index.d.ts",
   "exports": {
     ".": {
-      "types": "./build/jest.d.ts",
-      "default": "./build/jest.js"
+      "types": "./build/index.d.ts",
+      "default": "./build/index.js"
     },
     "./package.json": "./package.json",
     "./bin/jest": "./bin/jest.js"
diff --git a/packages/jest/src/jest.ts b/packages/jest/src/index.ts
similarity index 100%
rename from packages/jest/src/jest.ts
rename to packages/jest/src/index.ts
diff --git a/scripts/buildUtils.js b/scripts/buildUtils.js
index b645f5ac8531..2b5e7eba7cdf 100644
--- a/scripts/buildUtils.js
+++ b/scripts/buildUtils.js
@@ -74,6 +74,25 @@ module.exports.getPackages = function getPackages() {
       `Package "${pkg.name}" does not export correct files`,
     );
 
+    if (pkg.types) {
+      assert.strictEqual(
+        pkg.main,
+        './build/index.js',
+        `Package "${pkg.name}" should have "./build/index.js" as main`,
+      );
+      assert.strictEqual(
+        pkg.types,
+        './build/index.d.ts',
+        `Package "${pkg.name}" should have "./build/index.d.ts" as types`,
+      );
+    } else {
+      assert.strictEqual(
+        pkg.main,
+        './index.js',
+        `Package "${pkg.name}" should have "./index.js" as main`,
+      );
+    }
+
     if (pkg.bin) {
       Object.entries(pkg.bin).forEach(([binName, binPath]) => {
         const fullBinPath = path.resolve(packageDir, binPath);