Update to latest watchpack with dynamic route rename fix

packages/next/server/next-dev-server.ts

@@ -28,6 +28,7 @@ import ErrorDebug from './error-debug'
 import HotReloader from './hot-reloader'
 import { findPageFile } from './lib/find-page-file'
 import checkCustomRoutes from '../lib/check-custom-routes'
+import { recursiveReadDir } from '../lib/recursive-readdir'
 
 if (typeof React.Suspense === 'undefined') {
   throw new Error(
@@ -157,24 +158,22 @@ export default class DevServer extends Server {
       let wp = (this.webpackWatcher = new Watchpack())
       wp.watch([], [pagesDir!], 0)
 
-      wp.on('aggregated', () => {
+      wp.on('aggregated', async () => {
         const dynamicRoutedPages = []
-        const knownFiles = wp.getTimeInfoEntries()
-        for (const [fileName, { accuracy }] of knownFiles) {
-          if (accuracy === undefined) {
-            continue
-          }
-
-          let pageName =
-            '/' + relative(pagesDir!, fileName).replace(/\\+/g, '/')
-
-          pageName = pageName.replace(
-            new RegExp(`\\.+(?:${this.nextConfig.pageExtensions.join('|')})$`),
-            ''
+        const pageExtensionsRegex = new RegExp(
+          `\\.+(?:${this.nextConfig.pageExtensions.join('|')})$`
+        )
+        const curPageFiles = new Set(
+          (await recursiveReadDir(this.pagesDir!, pageExtensionsRegex)).map(
+            f =>
+              f
+                .replace(/\\/g, '/')
+                .replace(pageExtensionsRegex, '')
+                .replace(/\/index$/, '') || '/'
           )
+        )
 
-          pageName = pageName.replace(/\/index$/, '') || '/'
-
+        for (const pageName of curPageFiles) {
           if (!isDynamicRoute(pageName)) {
             continue
           }

test/integration/dynamic-route-rename/pages/[pid].js

@@ -0,0 +1 @@
+export default () => 'hi'

test/integration/dynamic-route-rename/test/index.test.js

@@ -0,0 +1,53 @@
+/* eslint-env jest */
+/* global jasmine */
+import fs from 'fs-extra'
+import { join } from 'path'
+import {
+  renderViaHTTP,
+  launchApp,
+  findPort,
+  killApp,
+  waitFor,
+} from 'next-test-utils'
+
+jasmine.DEFAULT_TIMEOUT_INTERVAL = 1000 * 30 * 2
+
+let app
+let appPort
+let stderr = ''
+
+const appDir = join(__dirname, '../')
+const pageFile = join(appDir, 'pages/[pid].js')
+const pageFileAlt = join(appDir, 'pages/[PiD].js')
+
+describe('Dynamic route rename casing', () => {
+  beforeAll(async () => {
+    appPort = await findPort()
+    app = await launchApp(appDir, appPort, {
+      onStderr(msg) {
+        stderr += msg || ''
+      },
+    })
+  })
+  afterAll(() => killApp(app))
+
+  it('should not throw error when changing casing of dynamic route file', async () => {
+    // make sure route is loaded in webpack
+    const html = await renderViaHTTP(appPort, '/abc')
+    expect(html).toContain('hi')
+
+    await fs.rename(pageFile, pageFileAlt)
+    await waitFor(2000)
+
+    expect(stderr).not.toContain(
+      `You cannot use different slug names for the same dynamic path`
+    )
+
+    await fs.rename(pageFileAlt, pageFile)
+    await waitFor(2000)
+
+    expect(stderr).not.toContain(
+      `You cannot use different slug names for the same dynamic path`
+    )
+  })
+})