test: add tests for legacy NextCustomServer methods

test/integration/custom-server/pages/404.js

@@ -0,0 +1 @@
+export default () => <p>made it to 404</p>

test/integration/custom-server/pages/500.js

@@ -0,0 +1 @@
+export default () => <p>made it to 500</p>

test/integration/custom-server/pages/dynamic-dashboard/index.js

@@ -0,0 +1,22 @@
+import { useRouter } from 'next/router'
+
+// NOTE: we want this page to be dynamic, otherwise the HTML won't contain search params
+export async function getServerSideProps() {
+  return { props: {} }
+}
+
+export default function Page() {
+  const router = useRouter()
+  const searchParam = router.query.q
+  return (
+    <p>
+      made it to dynamic dashboard
+      {!!searchParam && (
+        <>
+          <br />
+          query param: {searchParam}
+        </>
+      )}
+    </p>
+  )
+}

test/integration/custom-server/server.js

@@ -1,17 +1,27 @@
+// @ts-check
+
 if (process.env.POLYFILL_FETCH) {
+  // @ts-expect-error
   global.fetch = require('node-fetch').default
+  // @ts-expect-error
   global.Request = require('node-fetch').Request
+  // @ts-expect-error
   global.Headers = require('node-fetch').Headers
 }
 
 const { readFileSync } = require('fs')
+
+/** @type {import('next').default} */
+// @ts-ignore: missing interopDefault
 const next = require('next')
+
 const { join } = require('path')
 const { parse } = require('url')
 
 const dev = process.env.NODE_ENV !== 'production'
 const dir = __dirname
-const port = process.env.PORT || 3000
+const port =
+  (process.env.PORT ? Number.parseInt(process.env.PORT) : undefined) || 3000
 const { createServer } = require(
   process.env.USE_HTTPS === 'true' ? 'https' : 'http'
 )
@@ -30,6 +40,11 @@ process.on('unhandledRejection', (err) => {
 
 app.prepare().then(() => {
   const server = createServer(httpOptions, async (req, res) => {
+    // let next.js handle assets from /_next/
+    if (/\/_next\//.test(req.url)) {
+      return handleNextRequests(req, res)
+    }
+
     if (req.url === '/no-query') {
       return app.render(req, res, '/no-query')
     }
@@ -42,7 +57,7 @@ app.prepare().then(() => {
     if (/setAssetPrefix/.test(req.url)) {
       app.setAssetPrefix(`http://127.0.0.1:${port}`)
     } else if (/setEmptyAssetPrefix/.test(req.url)) {
-      app.setAssetPrefix(null)
+      app.setAssetPrefix('')
     } else {
       // This is to support multi-zones support in localhost
       // and may be in staging deployments
@@ -73,6 +88,56 @@ app.prepare().then(() => {
       return handleNextRequests(req, res, parse('/dashboard', true))
     }
 
+    if (/legacy-methods\/render-to-html/.test(req.url)) {
+      try {
+        const html = await app.renderToHTML(req, res, '/dynamic-dashboard', {
+          q: '1',
+        })
+        res.end(html)
+      } catch (err) {
+        res.end(err.message)
+      }
+      return
+    }
+
+    if (/legacy-methods\/render404/.test(req.url)) {
+      try {
+        await app.render404(req, res, parse('/__non_existent__?q=1', true))
+      } catch (err) {
+        res.end(err.message)
+      }
+      return
+    }
+
+    if (/legacy-methods\/render-error/.test(req.url)) {
+      try {
+        res.statusCode = 500
+        await app.renderError(new Error('kaboom'), req, res, '/dashboard', {
+          q: '1',
+        })
+      } catch (err) {
+        res.end(err.message)
+      }
+      return
+    }
+
+    if (/legacy-methods\/render-error-to-html/.test(req.url)) {
+      try {
+        res.statusCode = 500
+        const html = await app.renderErrorToHTML(
+          new Error('kaboom'),
+          req,
+          res,
+          '/dashboard',
+          { q: '1' }
+        )
+        res.end(html)
+      } catch (err) {
+        res.end(err.message)
+      }
+      return
+    }
+
     handleNextRequests(req, res)
   })
 

test/integration/custom-server/test/index.test.js

@@ -301,7 +301,7 @@ describe.each([
       await fetchViaHTTP(nextUrl, '/unhandled-rejection', undefined, { agent })
       await check(() => stderr, /unhandledRejection/)
       expect(stderr).toContain('unhandledRejection: Error: unhandled rejection')
-      expect(stderr).toContain('server.js:38:22')
+      expect(stderr).toMatch(/\/server\.js:\d+\d+/)
     })
   })
 
@@ -317,4 +317,72 @@ describe.each([
       )
     })
   })
+
+  describe.each(['development', 'production'])(
+    'legacy NextCustomServer methods - %s mode',
+    (mode) => {
+      const isNextDev = mode === 'development'
+
+      beforeAll(async () => {
+        if (!isNextDev) {
+          await nextBuild(appDir)
+        }
+        await startServer({ NODE_ENV: mode })
+      })
+      afterAll(() => killApp(server))
+
+      it('NextCustomServer.renderToHTML', async () => {
+        const rawHTML = await renderViaHTTP(
+          nextUrl,
+          '/legacy-methods/render-to-html?q=2',
+          undefined,
+          { agent }
+        )
+        const $ = cheerio.load(rawHTML)
+        const text = $('p').text()
+        expect(text).toContain('made it to dynamic dashboard')
+        expect(text).toContain('query param: 1')
+      })
+
+      it('NextCustomServer.render404', async () => {
+        const html = await renderViaHTTP(
+          nextUrl,
+          '/legacy-methods/render404',
+          undefined,
+          { agent }
+        )
+        expect(html).toContain('made it to 404')
+      })
+
+      it('NextCustomServer.renderError', async () => {
+        const html = await renderViaHTTP(
+          nextUrl,
+          '/legacy-methods/render-error',
+          undefined,
+          { agent }
+        )
+        if (isNextDev) {
+          // in dev, we always render error overlay + default error page, not /500
+          expect(html).toContain('Error: kaboom')
+        } else {
+          expect(html).toContain('made it to 500')
+        }
+      })
+
+      it('NextCustomServer.renderErrorToHTML', async () => {
+        const html = await renderViaHTTP(
+          nextUrl,
+          '/legacy-methods/render-error-to-html',
+          undefined,
+          { agent }
+        )
+        if (isNextDev) {
+          // in dev, we always render error overlay + default error page, not /500
+          expect(html).toContain('Error: kaboom')
+        } else {
+          expect(html).toContain('made it to 500')
+        }
+      })
+    }
+  )
 })

test/integration/filesystempublicroutes/server.js

@@ -13,7 +13,7 @@ app.prepare().then(() => {
     if (/setAssetPrefix/.test(req.url)) {
       app.setAssetPrefix(`http://127.0.0.1:${port}`)
     } else if (/setEmptyAssetPrefix/.test(req.url)) {
-      app.setAssetPrefix(null)
+      app.setAssetPrefix('')
     } else {
       // This is to support multi-zones support in localhost
       // and may be in staging deployments