Ensure next/jest is published

packages/next/build/jest/jest.ts

@@ -44,7 +44,7 @@ const customJestConfig = {
 // createJestConfig is exported in this way to ensure that next/jest can load the Next.js config which is async
 module.exports = createJestConfig(customJestConfig)
 */
-module.exports = function nextJest(options: { dir?: string } = {}) {
+export default function nextJest(options: { dir?: string } = {}) {
   // createJestConfig
   return (customJestConfig: any) => {
     // Function that is provided as the module.exports of jest.config.js

packages/next/jest.d.ts

@@ -0,0 +1,2 @@
+export * from './dist/build/jest/jest'
+export { default } from './dist/build/jest/jest'

packages/next/jest.js

@@ -1 +1,4 @@
-module.exports = require('./dist/build/jest/jest')
+function interopDefault(mod) {
+  return mod.default || mod
+}
+module.exports = interopDefault(require('./dist/build/jest/jest'))

packages/next/package.json

@@ -40,6 +40,8 @@
     "link.d.ts",
     "router.js",
     "router.d.ts",
+    "jest.js",
+    "jest.d.ts",
     "amp.js",
     "amp.d.ts",
     "types/index.d.ts",