Fix API page check during SSG page collecting

packages/next/build/index.ts

@@ -523,7 +523,9 @@ export default async function build(
       let isHybridAmp = false
       let ssgPageRoutes: string[] | null = null
 
-      const nonReservedPage = !page.match(/^\/(_app|_error|_document|api)/)
+      const nonReservedPage = !page.match(
+        /^\/(_app|_error|_document|api(\/|$))/
+      )
 
       if (nonReservedPage) {
         const serverBundle = getPagePath(page, distDir, isLikeServerless)

test/integration/prerender/pages/api-docs/[...slug].js

@@ -0,0 +1,27 @@
+import { useRouter } from 'next/router'
+
+export const getStaticProps = () => {
+  return {
+    props: {
+      hello: 'world',
+    },
+  }
+}
+
+export const getStaticPaths = () => {
+  return {
+    paths: ['/api-docs/first'],
+    fallback: true,
+  }
+}
+
+export default function Slug(props) {
+  if (useRouter().isFallback) return 'Loading...'
+
+  return (
+    <>
+      <p id="api-docs">API Docs</p>
+      <p id="props">{JSON.stringify(props)}</p>
+    </>
+  )
+}

test/integration/prerender/test/index.test.js

@@ -142,6 +142,11 @@ const expectedManifestRoutes = () => ({
     initialRevalidateSeconds: 1,
     srcRoute: null,
   },
+  '/api-docs/first': {
+    dataRoute: `/_next/data/${buildId}/api-docs/first.json`,
+    initialRevalidateSeconds: false,
+    srcRoute: '/api-docs/[...slug]',
+  },
   '/blocking-fallback-some/a': {
     dataRoute: `/_next/data/${buildId}/blocking-fallback-some/a.json`,
     initialRevalidateSeconds: 1,
@@ -602,6 +607,38 @@ const runTests = (dev = false, isEmulatedServerless = false) => {
     })
   }
 
+  it('should server prerendered path correctly for SSG pages that starts with api-docs', async () => {
+    const html = await renderViaHTTP(appPort, '/api-docs/first')
+    const $ = cheerio.load(html)
+
+    expect($('#api-docs').text()).toBe('API Docs')
+    expect(JSON.parse($('#props').text())).toEqual({
+      hello: 'world',
+    })
+  })
+
+  it('should render correctly for SSG pages that starts with api-docs', async () => {
+    const browser = await webdriver(appPort, '/api-docs/second')
+    await browser.waitForElementByCss('#api-docs')
+
+    expect(await browser.elementByCss('#api-docs').text()).toBe('API Docs')
+    expect(JSON.parse(await browser.elementByCss('#props').text())).toEqual({
+      hello: 'world',
+    })
+  })
+
+  it('should return data correctly for SSG pages that starts with api-docs', async () => {
+    const data = await renderViaHTTP(
+      appPort,
+      `/_next/data/${buildId}/api-docs/first.json`
+    )
+    const { pageProps } = JSON.parse(data)
+
+    expect(pageProps).toEqual({
+      hello: 'world',
+    })
+  })
+
   it('should SSR catch-all page with brackets in param as string', async () => {
     const html = await renderViaHTTP(
       appPort,
@@ -1136,6 +1173,20 @@ const runTests = (dev = false, isEmulatedServerless = false) => {
           ),
           page: '/another',
         },
+        {
+          dataRouteRegex: normalizeRegEx(
+            `^\\/_next\\/data\\/${escapeRegex(
+              buildId
+            )}\\/api\\-docs\\/(.+?)\\.json$`
+          ),
+          namedDataRouteRegex: `^/_next/data/${escapeRegex(
+            buildId
+          )}/api\\-docs/(?<slug>.+?)\\.json$`,
+          page: '/api-docs/[...slug]',
+          routeKeys: {
+            slug: 'slug',
+          },
+        },
         {
           dataRouteRegex: normalizeRegEx(
             `^\\/_next\\/data\\/${escapeRegex(buildId)}\\/bad-gssp.json$`
@@ -1388,6 +1439,14 @@ const runTests = (dev = false, isEmulatedServerless = false) => {
       expect(manifest.version).toBe(2)
       expect(manifest.routes).toEqual(expectedManifestRoutes())
       expect(manifest.dynamicRoutes).toEqual({
+        '/api-docs/[...slug]': {
+          dataRoute: `/_next/data/${buildId}/api-docs/[...slug].json`,
+          dataRouteRegex: normalizeRegEx(
+            `^\\/_next\\/data\\/${escapedBuildId}\\/api\\-docs\\/(.+?)\\.json$`
+          ),
+          fallback: '/api-docs/[...slug].html',
+          routeRegex: normalizeRegEx(`^\\/api\\-docs\\/(.+?)(?:\\/)?$`),
+        },
         '/blocking-fallback-once/[slug]': {
           dataRoute: `/_next/data/${buildId}/blocking-fallback-once/[slug].json`,
           dataRouteRegex: normalizeRegEx(
@@ -1995,6 +2054,7 @@ describe('SSG Prerender', () => {
       '/non-json/[p].js',
       '/blog/[post]/index.js',
       '/fallback-only/[slug].js',
+      '/api-docs/[...slug].js',
     ]
     const fallbackBlockingPages = [
       '/blocking-fallback/[slug].js',