Improve top level await coverage (#64508)

## What?

- Changes webpack output target to `es6` (required for `async function`
output)
- Adds tests for top level await in server components and client
components (App Router)
- Converted the async-modules tests to `test/e2e`
- Has one skipped test that @gnoff is going to look into. This shouldn't
block merging this PR 👍


Adds additional tests for top level `await`.

Since [Next.js
13.4.5](https://github.com/vercel/next.js/releases/tag/v13.4.5) webpack
has top level await support enabled by default.

Similarly Turbopack supports top level await by default as well.

TLDR: You can remove `topLevelAwait: true` from the webpack
configuration.


In writing these tests I found that client components are missing some
kind of handling for top level await (async modules) so I've raised that
to @gnoff who is going to have a look.

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Closes NEXT-3126
Fixes https://github.com/vercel/next.js/issues/43382

.eslintignore

@@ -42,3 +42,4 @@ test/development/basic/hmr/components/parse-error.js
 packages/next-swc/docs/assets/**/*
 test/lib/amp-validator-wasm.js
 test/production/pages-dir/production/fixture/amp-validator-wasm.js
+test/e2e/async-modules/amp-validator-wasm.js

.prettierignore

@@ -39,3 +39,4 @@ bench/nested-deps/components/**/*
 **/.tina/__generated__/**
 test/lib/amp-validator-wasm.js
 test/production/pages-dir/production/fixture/amp-validator-wasm.js
+test/e2e/async-modules/amp-validator-wasm.js

packages/next/src/build/webpack/config/blocks/base.ts

@@ -18,7 +18,7 @@ export const base = curry(function base(
     ? 'node18.17' // Same version defined in packages/next/package.json#engines
     : ctx.isEdgeRuntime
     ? ['web', 'es6']
-    : ['web', 'es5']
+    : ['web', 'es6']
 
   // https://webpack.js.org/configuration/devtool/#development
   if (ctx.isDevelopment) {

packages/next/src/lib/typescript/writeConfigurationDefaults.ts

@@ -9,7 +9,7 @@ import * as Log from '../../build/output/log'
 
 type DesiredCompilerOptionsShape = {
   [K in keyof CompilerOptions]:
-    | { suggested: any }
+    | { suggested: any; reason?: string }
     | {
         parsedValue?: any
         parsedValues?: Array<any>
@@ -23,6 +23,11 @@ function getDesiredCompilerOptions(
   tsOptions?: CompilerOptions
 ): DesiredCompilerOptionsShape {
   const o: DesiredCompilerOptionsShape = {
+    target: {
+      suggested: 'ES2017',
+      reason:
+        'For top-level `await`. Note: Next.js only polyfills for the esmodules target.',
+    },
     // These are suggested values and will be set when not present in the
     // tsconfig.json
     lib: { suggested: ['dom', 'dom.iterable', 'esnext'] },
@@ -168,7 +173,12 @@ export async function writeConfigurationDefaults(
         }
         userTsConfig.compilerOptions[optionKey] = check.suggested
         suggestedActions.push(
-          cyan(optionKey) + ' was set to ' + bold(check.suggested)
+          cyan(optionKey) +
+            ' was set to ' +
+            bold(check.suggested) +
+            check.reason
+            ? ` (${check.reason})`
+            : ''
         )
       }
     } else if ('value' in check) {

test/e2e/async-modules-app/app/app-router/client-component/skipped-page.tsx

@@ -0,0 +1,6 @@
+'use client'
+const appValue = await Promise.resolve('hello')
+
+export default function Page() {
+  return <p id="app-router-client-component-value">{appValue}</p>
+}

test/e2e/async-modules-app/app/app-router/page.tsx

@@ -0,0 +1,5 @@
+const appValue = await Promise.resolve('hello')
+
+export default function Page() {
+  return <p id="app-router-value">{appValue}</p>
+}

test/e2e/async-modules-app/app/layout.tsx

@@ -0,0 +1,16 @@
+export const metadata = {
+  title: 'Next.js',
+  description: 'Generated by Next.js',
+}
+
+export default function RootLayout({
+  children,
+}: {
+  children: React.ReactNode
+}) {
+  return (
+    <html lang="en">
+      <body>{children}</body>
+    </html>
+  )
+}

test/e2e/async-modules-app/index.test.ts

@@ -0,0 +1,21 @@
+/* eslint-env jest */
+import { nextTestSetup } from 'e2e-utils'
+
+describe('Async modules', () => {
+  const { next } = nextTestSetup({
+    files: __dirname,
+  })
+  it('app router server component async module', async () => {
+    const browser = await next.browser('/app-router')
+    expect(await browser.elementByCss('#app-router-value').text()).toBe('hello')
+  })
+
+  // TODO: Investigate/fix issue with React loading async modules failing.
+  // Rename app/app-router/client-component/skipped-page.tsx to app/app-router/client-component/page.tsx to run this test.
+  it.skip('app router client component async module', async () => {
+    const browser = await next.browser('/app-router/client')
+    expect(
+      await browser.elementByCss('#app-router-client-component-value').text()
+    ).toBe('hello')
+  })
+})

test/e2e/async-modules-app/next.config.js

@@ -0,0 +1 @@
+module.exports = {}

test/e2e/async-modules/index.test.ts

@@ -0,0 +1,60 @@
+/* eslint-env jest */
+import { nextTestSetup } from 'e2e-utils'
+import { check } from 'next-test-utils'
+
+describe('Async modules', () => {
+  const { next, isNextDev: dev } = nextTestSetup({
+    files: __dirname,
+  })
+
+  it('ssr async page modules', async () => {
+    const $ = await next.render$('/')
+    expect($('#app-value').text()).toBe('hello')
+    expect($('#page-value').text()).toBe('42')
+  })
+
+  it('csr async page modules', async () => {
+    const browser = await next.browser('/')
+    expect(await browser.elementByCss('#app-value').text()).toBe('hello')
+    expect(await browser.elementByCss('#page-value').text()).toBe('42')
+    expect(await browser.elementByCss('#doc-value').text()).toBe('doc value')
+  })
+
+  it('works on async api routes', async () => {
+    const res = await next.fetch('/api/hello')
+    expect(res.status).toBe(200)
+    const result = await res.json()
+    expect(result).toHaveProperty('value', 42)
+  })
+
+  it('works with getServerSideProps', async () => {
+    const browser = await next.browser('/gssp')
+    expect(await browser.elementByCss('#gssp-value').text()).toBe('42')
+  })
+
+  it('works with getStaticProps', async () => {
+    const browser = await next.browser('/gsp')
+    expect(await browser.elementByCss('#gsp-value').text()).toBe('42')
+  })
+
+  it('can render async 404 pages', async () => {
+    const browser = await next.browser('/dhiuhefoiahjeoij')
+    expect(await browser.elementByCss('#content-404').text()).toBe("hi y'all")
+  })
+
+  // TODO: investigate this test flaking
+  it.skip('can render async AMP pages', async () => {
+    const browser = await next.browser('/config')
+    await check(
+      () => browser.elementByCss('#amp-timeago').text(),
+      'just now',
+      true
+    )
+  })
+  ;(dev ? it.skip : it)('can render async error page', async () => {
+    const browser = await next.browser('/make-error')
+    expect(await browser.elementByCss('#content-error').text()).toBe(
+      'hello error'
+    )
+  })
+})

test/e2e/async-modules/next.config.js

@@ -0,0 +1,7 @@
+module.exports = {
+  experimental: {
+    amp: {
+      validator: require.resolve('./amp-validator-wasm.js'),
+    },
+  },
+}

test/e2e/tsconfig-module-preserve/index.test.ts

@@ -37,6 +37,7 @@ describe('tsconfig module: preserve', () => {
       "{
         "compilerOptions": {
           "module": "preserve",
+          "target": "ES2017",
           "lib": [
             "dom",
             "dom.iterable",

test/integration/async-modules/next.config.js

@@ -1,12 +0,0 @@
-module.exports = {
-  webpack: (config) => {
-    config.experiments = config.experiments || {}
-    config.experiments.topLevelAwait = true
-    return config
-  },
-  experimental: {
-    amp: {
-      validator: require.resolve('../../lib/amp-validator-wasm.js'),
-    },
-  },
-}

test/integration/async-modules/test/index.test.js

@@ -1,136 +0,0 @@
-/* eslint-env jest */
-
-import webdriver from 'next-webdriver'
-
-import cheerio from 'cheerio'
-import {
-  fetchViaHTTP,
-  renderViaHTTP,
-  findPort,
-  killApp,
-  launchApp,
-  nextBuild,
-  nextStart,
-  check,
-} from 'next-test-utils'
-import { join } from 'path'
-
-let app
-let appPort
-const appDir = join(__dirname, '../')
-
-function runTests(dev = false) {
-  it('ssr async page modules', async () => {
-    const html = await renderViaHTTP(appPort, '/')
-    const $ = cheerio.load(html)
-    expect($('#app-value').text()).toBe('hello')
-    expect($('#page-value').text()).toBe('42')
-  })
-
-  it('csr async page modules', async () => {
-    let browser
-    try {
-      browser = await webdriver(appPort, '/')
-      expect(await browser.elementByCss('#app-value').text()).toBe('hello')
-      expect(await browser.elementByCss('#page-value').text()).toBe('42')
-      expect(await browser.elementByCss('#doc-value').text()).toBe('doc value')
-    } finally {
-      if (browser) await browser.close()
-    }
-  })
-
-  it('works on async api routes', async () => {
-    const res = await fetchViaHTTP(appPort, '/api/hello')
-    expect(res.status).toBe(200)
-    const result = await res.json()
-    expect(result).toHaveProperty('value', 42)
-  })
-
-  it('works with getServerSideProps', async () => {
-    let browser
-    try {
-      browser = await webdriver(appPort, '/gssp')
-      expect(await browser.elementByCss('#gssp-value').text()).toBe('42')
-    } finally {
-      if (browser) await browser.close()
-    }
-  })
-
-  it('works with getStaticProps', async () => {
-    let browser
-    try {
-      browser = await webdriver(appPort, '/gsp')
-      expect(await browser.elementByCss('#gsp-value').text()).toBe('42')
-    } finally {
-      if (browser) await browser.close()
-    }
-  })
-
-  it('can render async 404 pages', async () => {
-    let browser
-    try {
-      browser = await webdriver(appPort, '/dhiuhefoiahjeoij')
-      expect(await browser.elementByCss('#content-404').text()).toBe("hi y'all")
-    } finally {
-      if (browser) await browser.close()
-    }
-  })
-
-  // TODO: investigate this test flaking
-  it.skip('can render async AMP pages', async () => {
-    let browser
-    try {
-      browser = await webdriver(appPort, '/config')
-      await check(
-        () => browser.elementByCss('#amp-timeago').text(),
-        'just now',
-        true
-      )
-    } finally {
-      if (browser) await browser.close()
-    }
-  })
-  ;(dev ? it.skip : it)('can render async error page', async () => {
-    let browser
-    try {
-      browser = await webdriver(appPort, '/make-error')
-      expect(await browser.elementByCss('#content-error').text()).toBe(
-        'hello error'
-      )
-    } finally {
-      if (browser) await browser.close()
-    }
-  })
-}
-
-describe('Async modules', () => {
-  ;(process.env.TURBOPACK_BUILD ? describe.skip : describe)(
-    'development mode',
-    () => {
-      beforeAll(async () => {
-        appPort = await findPort()
-        app = await launchApp(appDir, appPort)
-      })
-      afterAll(async () => {
-        await killApp(app)
-      })
-
-      runTests(true)
-    }
-  )
-  ;(process.env.TURBOPACK_DEV ? describe.skip : describe)(
-    'production mode',
-    () => {
-      beforeAll(async () => {
-        await nextBuild(appDir)
-        appPort = await findPort()
-        app = await nextStart(appDir, appPort)
-      })
-      afterAll(async () => {
-        await killApp(app)
-      })
-
-      runTests()
-    }
-  )
-})

test/integration/tsconfig-verifier/test/index.test.js

@@ -25,43 +25,44 @@ import path from 'path'
       const { code } = await nextBuild(appDir)
       expect(code).toBe(0)
       expect(await readFile(tsConfig, 'utf8')).toMatchInlineSnapshot(`
-      "{
-        "compilerOptions": {
-          "lib": [
-            "dom",
-            "dom.iterable",
-            "esnext"
+        "{
+          "compilerOptions": {
+            "target": "ES2017",
+            "lib": [
+              "dom",
+              "dom.iterable",
+              "esnext"
+            ],
+            "allowJs": true,
+            "skipLibCheck": true,
+            "strict": false,
+            "noEmit": true,
+            "incremental": true,
+            "module": "esnext",
+            "esModuleInterop": true,
+            "moduleResolution": "node",
+            "resolveJsonModule": true,
+            "isolatedModules": true,
+            "jsx": "preserve",
+            "plugins": [
+              {
+                "name": "next"
+              }
+            ],
+            "strictNullChecks": true
+          },
+          "include": [
+            "next-env.d.ts",
+            ".next/types/**/*.ts",
+            "**/*.ts",
+            "**/*.tsx"
           ],
-          "allowJs": true,
-          "skipLibCheck": true,
-          "strict": false,
-          "noEmit": true,
-          "incremental": true,
-          "module": "esnext",
-          "esModuleInterop": true,
-          "moduleResolution": "node",
-          "resolveJsonModule": true,
-          "isolatedModules": true,
-          "jsx": "preserve",
-          "plugins": [
-            {
-              "name": "next"
-            }
-          ],
-          "strictNullChecks": true
-        },
-        "include": [
-          "next-env.d.ts",
-          ".next/types/**/*.ts",
-          "**/*.ts",
-          "**/*.tsx"
-        ],
-        "exclude": [
-          "node_modules"
-        ]
-      }
-      "
-    `)
+          "exclude": [
+            "node_modules"
+          ]
+        }
+        "
+      `)
     })
 
     it('Works with an empty tsconfig.json (docs)', async () => {
@@ -79,43 +80,44 @@ import path from 'path'
       expect(code).toBe(0)
 
       expect(await readFile(tsConfig, 'utf8')).toMatchInlineSnapshot(`
-      "{
-        "compilerOptions": {
-          "lib": [
-            "dom",
-            "dom.iterable",
-            "esnext"
+        "{
+          "compilerOptions": {
+            "target": "ES2017",
+            "lib": [
+              "dom",
+              "dom.iterable",
+              "esnext"
+            ],
+            "allowJs": true,
+            "skipLibCheck": true,
+            "strict": false,
+            "noEmit": true,
+            "incremental": true,
+            "module": "esnext",
+            "esModuleInterop": true,
+            "moduleResolution": "node",
+            "resolveJsonModule": true,
+            "isolatedModules": true,
+            "jsx": "preserve",
+            "plugins": [
+              {
+                "name": "next"
+              }
+            ],
+            "strictNullChecks": true
+          },
+          "include": [
+            "next-env.d.ts",
+            ".next/types/**/*.ts",
+            "**/*.ts",
+            "**/*.tsx"
           ],
-          "allowJs": true,
-          "skipLibCheck": true,
-          "strict": false,
-          "noEmit": true,
-          "incremental": true,
-          "module": "esnext",
-          "esModuleInterop": true,
-          "moduleResolution": "node",
-          "resolveJsonModule": true,
-          "isolatedModules": true,
-          "jsx": "preserve",
-          "plugins": [
-            {
-              "name": "next"
-            }
-          ],
-          "strictNullChecks": true
-        },
-        "include": [
-          "next-env.d.ts",
-          ".next/types/**/*.ts",
-          "**/*.ts",
-          "**/*.tsx"
-        ],
-        "exclude": [
-          "node_modules"
-        ]
-      }
-      "
-    `)
+          "exclude": [
+            "node_modules"
+          ]
+        }
+        "
+      `)
     })
 
     it('Updates an existing tsconfig.json without losing comments', async () => {
@@ -145,51 +147,52 @@ import path from 'path'
       // Weird comma placement until this issue is resolved:
       // https://github.com/kaelzhang/node-comment-json/issues/21
       expect(await readFile(tsConfig, 'utf8')).toMatchInlineSnapshot(`
-      "// top-level comment
-      {
-        // in-object comment 1
-        "compilerOptions": {
-          // in-object comment
-          "esModuleInterop": true, // this should be true
-          "module": "esnext" // should not be umd
-          // end-object comment
+        "// top-level comment
+        {
+          // in-object comment 1
+          "compilerOptions": {
+            // in-object comment
+            "esModuleInterop": true, // this should be true
+            "module": "esnext" // should not be umd
+            // end-object comment
+            ,
+            "target": "ES2017",
+            "lib": [
+              "dom",
+              "dom.iterable",
+              "esnext"
+            ],
+            "allowJs": true,
+            "skipLibCheck": true,
+            "strict": false,
+            "noEmit": true,
+            "incremental": true,
+            "moduleResolution": "node",
+            "resolveJsonModule": true,
+            "isolatedModules": true,
+            "jsx": "preserve",
+            "plugins": [
+              {
+                "name": "next"
+              }
+            ],
+            "strictNullChecks": true
+          }
+          // in-object comment 2
           ,
-          "lib": [
-            "dom",
-            "dom.iterable",
-            "esnext"
+          "include": [
+            "next-env.d.ts",
+            ".next/types/**/*.ts",
+            "**/*.ts",
+            "**/*.tsx"
           ],
-          "allowJs": true,
-          "skipLibCheck": true,
-          "strict": false,
-          "noEmit": true,
-          "incremental": true,
-          "moduleResolution": "node",
-          "resolveJsonModule": true,
-          "isolatedModules": true,
-          "jsx": "preserve",
-          "plugins": [
-            {
-              "name": "next"
-            }
-          ],
-          "strictNullChecks": true
+          "exclude": [
+            "node_modules"
+          ]
         }
-        // in-object comment 2
-        ,
-        "include": [
-          "next-env.d.ts",
-          ".next/types/**/*.ts",
-          "**/*.ts",
-          "**/*.tsx"
-        ],
-        "exclude": [
-          "node_modules"
-        ]
-      }
-      // end comment
-      "
-    `)
+        // end comment
+        "
+      `)
     })
 
     it('allows you to set commonjs module mode', async () => {
@@ -204,43 +207,44 @@ import path from 'path'
       expect(code).toBe(0)
 
       expect(await readFile(tsConfig, 'utf8')).toMatchInlineSnapshot(`
-      "{
-        "compilerOptions": {
-          "esModuleInterop": true,
-          "module": "commonjs",
-          "lib": [
-            "dom",
-            "dom.iterable",
-            "esnext"
+        "{
+          "compilerOptions": {
+            "esModuleInterop": true,
+            "module": "commonjs",
+            "target": "ES2017",
+            "lib": [
+              "dom",
+              "dom.iterable",
+              "esnext"
+            ],
+            "allowJs": true,
+            "skipLibCheck": true,
+            "strict": false,
+            "noEmit": true,
+            "incremental": true,
+            "moduleResolution": "node",
+            "resolveJsonModule": true,
+            "isolatedModules": true,
+            "jsx": "preserve",
+            "plugins": [
+              {
+                "name": "next"
+              }
+            ],
+            "strictNullChecks": true
+          },
+          "include": [
+            "next-env.d.ts",
+            ".next/types/**/*.ts",
+            "**/*.ts",
+            "**/*.tsx"
           ],
-          "allowJs": true,
-          "skipLibCheck": true,
-          "strict": false,
-          "noEmit": true,
-          "incremental": true,
-          "moduleResolution": "node",
-          "resolveJsonModule": true,
-          "isolatedModules": true,
-          "jsx": "preserve",
-          "plugins": [
-            {
-              "name": "next"
-            }
-          ],
-          "strictNullChecks": true
-        },
-        "include": [
-          "next-env.d.ts",
-          ".next/types/**/*.ts",
-          "**/*.ts",
-          "**/*.tsx"
-        ],
-        "exclude": [
-          "node_modules"
-        ]
-      }
-      "
-    `)
+          "exclude": [
+            "node_modules"
+          ]
+        }
+        "
+      `)
     })
 
     it('allows you to set es2020 module mode', async () => {
@@ -255,43 +259,44 @@ import path from 'path'
       expect(code).toBe(0)
 
       expect(await readFile(tsConfig, 'utf8')).toMatchInlineSnapshot(`
-      "{
-        "compilerOptions": {
-          "esModuleInterop": true,
-          "module": "es2020",
-          "lib": [
-            "dom",
-            "dom.iterable",
-            "esnext"
+        "{
+          "compilerOptions": {
+            "esModuleInterop": true,
+            "module": "es2020",
+            "target": "ES2017",
+            "lib": [
+              "dom",
+              "dom.iterable",
+              "esnext"
+            ],
+            "allowJs": true,
+            "skipLibCheck": true,
+            "strict": false,
+            "noEmit": true,
+            "incremental": true,
+            "moduleResolution": "node",
+            "resolveJsonModule": true,
+            "isolatedModules": true,
+            "jsx": "preserve",
+            "plugins": [
+              {
+                "name": "next"
+              }
+            ],
+            "strictNullChecks": true
+          },
+          "include": [
+            "next-env.d.ts",
+            ".next/types/**/*.ts",
+            "**/*.ts",
+            "**/*.tsx"
           ],
-          "allowJs": true,
-          "skipLibCheck": true,
-          "strict": false,
-          "noEmit": true,
-          "incremental": true,
-          "moduleResolution": "node",
-          "resolveJsonModule": true,
-          "isolatedModules": true,
-          "jsx": "preserve",
-          "plugins": [
-            {
-              "name": "next"
-            }
-          ],
-          "strictNullChecks": true
-        },
-        "include": [
-          "next-env.d.ts",
-          ".next/types/**/*.ts",
-          "**/*.ts",
-          "**/*.tsx"
-        ],
-        "exclude": [
-          "node_modules"
-        ]
-      }
-      "
-    `)
+          "exclude": [
+            "node_modules"
+          ]
+        }
+        "
+      `)
     })
 
     it('allows you to set node16 moduleResolution mode', async () => {
@@ -310,43 +315,44 @@ import path from 'path'
       expect(code).toBe(0)
 
       expect(await readFile(tsConfig, 'utf8')).toMatchInlineSnapshot(`
-      "{
-        "compilerOptions": {
-          "esModuleInterop": true,
-          "moduleResolution": "node16",
-          "module": "node16",
-          "lib": [
-            "dom",
-            "dom.iterable",
-            "esnext"
+        "{
+          "compilerOptions": {
+            "esModuleInterop": true,
+            "moduleResolution": "node16",
+            "module": "node16",
+            "target": "ES2017",
+            "lib": [
+              "dom",
+              "dom.iterable",
+              "esnext"
+            ],
+            "allowJs": true,
+            "skipLibCheck": true,
+            "strict": false,
+            "noEmit": true,
+            "incremental": true,
+            "resolveJsonModule": true,
+            "isolatedModules": true,
+            "jsx": "preserve",
+            "plugins": [
+              {
+                "name": "next"
+              }
+            ],
+            "strictNullChecks": true
+          },
+          "include": [
+            "next-env.d.ts",
+            ".next/types/**/*.ts",
+            "**/*.ts",
+            "**/*.tsx"
           ],
-          "allowJs": true,
-          "skipLibCheck": true,
-          "strict": false,
-          "noEmit": true,
-          "incremental": true,
-          "resolveJsonModule": true,
-          "isolatedModules": true,
-          "jsx": "preserve",
-          "plugins": [
-            {
-              "name": "next"
-            }
-          ],
-          "strictNullChecks": true
-        },
-        "include": [
-          "next-env.d.ts",
-          ".next/types/**/*.ts",
-          "**/*.ts",
-          "**/*.tsx"
-        ],
-        "exclude": [
-          "node_modules"
-        ]
-      }
-      "
-    `)
+          "exclude": [
+            "node_modules"
+          ]
+        }
+        "
+      `)
     })
 
     it('allows you to set bundler moduleResolution mode', async () => {
@@ -365,43 +371,44 @@ import path from 'path'
       expect(code).toBe(0)
 
       expect(await readFile(tsConfig, 'utf8')).toMatchInlineSnapshot(`
-      "{
-        "compilerOptions": {
-          "esModuleInterop": true,
-          "moduleResolution": "bundler",
-          "lib": [
-            "dom",
-            "dom.iterable",
-            "esnext"
+        "{
+          "compilerOptions": {
+            "esModuleInterop": true,
+            "moduleResolution": "bundler",
+            "target": "ES2017",
+            "lib": [
+              "dom",
+              "dom.iterable",
+              "esnext"
+            ],
+            "allowJs": true,
+            "skipLibCheck": true,
+            "strict": false,
+            "noEmit": true,
+            "incremental": true,
+            "module": "esnext",
+            "resolveJsonModule": true,
+            "isolatedModules": true,
+            "jsx": "preserve",
+            "plugins": [
+              {
+                "name": "next"
+              }
+            ],
+            "strictNullChecks": true
+          },
+          "include": [
+            "next-env.d.ts",
+            ".next/types/**/*.ts",
+            "**/*.ts",
+            "**/*.tsx"
           ],
-          "allowJs": true,
-          "skipLibCheck": true,
-          "strict": false,
-          "noEmit": true,
-          "incremental": true,
-          "module": "esnext",
-          "resolveJsonModule": true,
-          "isolatedModules": true,
-          "jsx": "preserve",
-          "plugins": [
-            {
-              "name": "next"
-            }
-          ],
-          "strictNullChecks": true
-        },
-        "include": [
-          "next-env.d.ts",
-          ".next/types/**/*.ts",
-          "**/*.ts",
-          "**/*.tsx"
-        ],
-        "exclude": [
-          "node_modules"
-        ]
-      }
-      "
-    `)
+          "exclude": [
+            "node_modules"
+          ]
+        }
+        "
+      `)
     })
 
     it('allows you to set target mode', async () => {
@@ -417,44 +424,44 @@ import path from 'path'
       expect(code).toBe(0)
 
       expect(await readFile(tsConfig, 'utf8')).toMatchInlineSnapshot(`
-      "{
-        "compilerOptions": {
-          "target": "es2022",
-          "lib": [
-            "dom",
-            "dom.iterable",
-            "esnext"
-          ],
-          "allowJs": true,
-          "skipLibCheck": true,
-          "strict": false,
-          "noEmit": true,
-          "incremental": true,
-          "module": "esnext",
-          "esModuleInterop": true,
-          "moduleResolution": "node",
-          "resolveJsonModule": true,
-          "isolatedModules": true,
-          "jsx": "preserve",
-          "plugins": [
-            {
-              "name": "next"
-            }
-          ],
-          "strictNullChecks": true
-        },
-        "include": [
-          "next-env.d.ts",
-          ".next/types/**/*.ts",
-          "**/*.ts",
-          "**/*.tsx"
-        ],
-        "exclude": [
-          "node_modules"
-        ]
-      }
-      "
-    `)
+              "{
+                "compilerOptions": {
+                  "target": "es2022",
+                  "lib": [
+                    "dom",
+                    "dom.iterable",
+                    "esnext"
+                  ],
+                  "allowJs": true,
+                  "skipLibCheck": true,
+                  "strict": false,
+                  "noEmit": true,
+                  "incremental": true,
+                  "module": "esnext",
+                  "esModuleInterop": true,
+                  "moduleResolution": "node",
+                  "resolveJsonModule": true,
+                  "isolatedModules": true,
+                  "jsx": "preserve",
+                  "plugins": [
+                    {
+                      "name": "next"
+                    }
+                  ],
+                  "strictNullChecks": true
+                },
+                "include": [
+                  "next-env.d.ts",
+                  ".next/types/**/*.ts",
+                  "**/*.ts",
+                  "**/*.tsx"
+                ],
+                "exclude": [
+                  "node_modules"
+                ]
+              }
+              "
+          `)
     })
 
     it('allows you to set node16 module mode', async () => {
@@ -473,43 +480,44 @@ import path from 'path'
       expect(code).toBe(0)
 
       expect(await readFile(tsConfig, 'utf8')).toMatchInlineSnapshot(`
-      "{
-        "compilerOptions": {
-          "esModuleInterop": true,
-          "module": "node16",
-          "moduleResolution": "node16",
-          "lib": [
-            "dom",
-            "dom.iterable",
-            "esnext"
+        "{
+          "compilerOptions": {
+            "esModuleInterop": true,
+            "module": "node16",
+            "moduleResolution": "node16",
+            "target": "ES2017",
+            "lib": [
+              "dom",
+              "dom.iterable",
+              "esnext"
+            ],
+            "allowJs": true,
+            "skipLibCheck": true,
+            "strict": false,
+            "noEmit": true,
+            "incremental": true,
+            "resolveJsonModule": true,
+            "isolatedModules": true,
+            "jsx": "preserve",
+            "plugins": [
+              {
+                "name": "next"
+              }
+            ],
+            "strictNullChecks": true
+          },
+          "include": [
+            "next-env.d.ts",
+            ".next/types/**/*.ts",
+            "**/*.ts",
+            "**/*.tsx"
           ],
-          "allowJs": true,
-          "skipLibCheck": true,
-          "strict": false,
-          "noEmit": true,
-          "incremental": true,
-          "resolveJsonModule": true,
-          "isolatedModules": true,
-          "jsx": "preserve",
-          "plugins": [
-            {
-              "name": "next"
-            }
-          ],
-          "strictNullChecks": true
-        },
-        "include": [
-          "next-env.d.ts",
-          ".next/types/**/*.ts",
-          "**/*.ts",
-          "**/*.tsx"
-        ],
-        "exclude": [
-          "node_modules"
-        ]
-      }
-      "
-    `)
+          "exclude": [
+            "node_modules"
+          ]
+        }
+        "
+      `)
     })
 
     it('allows you to set verbatimModuleSyntax true without adding isolatedModules', async () => {
@@ -528,43 +536,44 @@ import path from 'path'
       expect(code).toBe(0)
 
       expect(await readFile(tsConfig, 'utf8')).toMatchInlineSnapshot(`
-      "{
-        "compilerOptions": {
-          "verbatimModuleSyntax": true,
-          "lib": [
-            "dom",
-            "dom.iterable",
-            "esnext"
+        "{
+          "compilerOptions": {
+            "verbatimModuleSyntax": true,
+            "target": "ES2017",
+            "lib": [
+              "dom",
+              "dom.iterable",
+              "esnext"
+            ],
+            "allowJs": true,
+            "skipLibCheck": true,
+            "strict": false,
+            "noEmit": true,
+            "incremental": true,
+            "module": "esnext",
+            "esModuleInterop": true,
+            "moduleResolution": "node",
+            "resolveJsonModule": true,
+            "jsx": "preserve",
+            "plugins": [
+              {
+                "name": "next"
+              }
+            ],
+            "strictNullChecks": true
+          },
+          "include": [
+            "next-env.d.ts",
+            ".next/types/**/*.ts",
+            "**/*.ts",
+            "**/*.tsx"
           ],
-          "allowJs": true,
-          "skipLibCheck": true,
-          "strict": false,
-          "noEmit": true,
-          "incremental": true,
-          "module": "esnext",
-          "esModuleInterop": true,
-          "moduleResolution": "node",
-          "resolveJsonModule": true,
-          "jsx": "preserve",
-          "plugins": [
-            {
-              "name": "next"
-            }
-          ],
-          "strictNullChecks": true
-        },
-        "include": [
-          "next-env.d.ts",
-          ".next/types/**/*.ts",
-          "**/*.ts",
-          "**/*.tsx"
-        ],
-        "exclude": [
-          "node_modules"
-        ]
-      }
-      "
-    `)
+          "exclude": [
+            "node_modules"
+          ]
+        }
+        "
+      `)
     })
 
     it('allows you to set verbatimModuleSyntax true via extends without adding isolatedModules', async () => {
@@ -588,6 +597,7 @@ import path from 'path'
         "{
           "extends": "./tsconfig.base.json",
           "compilerOptions": {
+            "target": "ES2017",
             "lib": [
               "dom",
               "dom.iterable",
@@ -681,9 +691,16 @@ import path from 'path'
       expect(stderr + stdout).not.toContain('moduleResolution')
       expect(code).toBe(0)
 
-      expect(await readFile(tsConfig, 'utf8')).toMatchInlineSnapshot(
-        `"{ "extends": "./tsconfig.base.json" }"`
-      )
+      expect(await readFile(tsConfig, 'utf8')).toMatchInlineSnapshot(`
+        "{
+          "extends": "./tsconfig.base.json",
+          "compilerOptions": {
+            "target": "ES2017",
+            "strictNullChecks": true
+          }
+        }
+        "
+      `)
     })
 
     it('creates compilerOptions when you extend another config', async () => {
@@ -743,15 +760,16 @@ import path from 'path'
       expect(code).toBe(0)
 
       expect(await readFile(tsConfig, 'utf8')).toMatchInlineSnapshot(`
-      "{
-        "extends": "./tsconfig.base.json",
-        "compilerOptions": {
-          "incremental": true,
-          "strictNullChecks": true
+        "{
+          "extends": "./tsconfig.base.json",
+          "compilerOptions": {
+            "target": "ES2017",
+            "incremental": true,
+            "strictNullChecks": true
+          }
         }
-      }
-      "
-    `)
+        "
+      `)
     })
 
     // TODO: Enable this test when repo has upgraded to TypeScript 5.4. Currently tested as E2E: tsconfig-module-preserve
@@ -773,40 +791,40 @@ import path from 'path'
       expect(code).toBe(0)
 
       expect(await readFile(tsConfig, 'utf8')).toMatchInlineSnapshot(`
-      "{
-        "compilerOptions": {
-          "module": "preserve",
-          "lib": [
-            "dom",
-            "dom.iterable",
-            "esnext"
-          ],
-          "allowJs": true,
-          "skipLibCheck": true,
-          "strict": false,
-          "noEmit": true,
-          "incremental": true,
-          "isolatedModules": true,
-          "jsx": "preserve",
-          "plugins": [
-            {
-              "name": "next"
-            }
-          ],
-          "strictNullChecks": true
-        },
-        "include": [
-          "next-env.d.ts",
-          ".next/types/**/*.ts",
-          "**/*.ts",
-          "**/*.tsx"
-        ],
-        "exclude": [
-          "node_modules"
-        ]
-      }
-      "
-    `)
+              "{
+                "compilerOptions": {
+                  "module": "preserve",
+                  "lib": [
+                    "dom",
+                    "dom.iterable",
+                    "esnext"
+                  ],
+                  "allowJs": true,
+                  "skipLibCheck": true,
+                  "strict": false,
+                  "noEmit": true,
+                  "incremental": true,
+                  "isolatedModules": true,
+                  "jsx": "preserve",
+                  "plugins": [
+                    {
+                      "name": "next"
+                    }
+                  ],
+                  "strictNullChecks": true
+                },
+                "include": [
+                  "next-env.d.ts",
+                  ".next/types/**/*.ts",
+                  "**/*.ts",
+                  "**/*.tsx"
+                ],
+                "exclude": [
+                  "node_modules"
+                ]
+              }
+              "
+          `)
     })
   }
 )