test: next.js repo tests adjustments (#3168)

Author: pieh

.github/workflows/test-e2e.yml

@@ -124,6 +124,24 @@ jobs:
           echo "version=$NODE_VERSION" >> $GITHUB_OUTPUT
           echo "Node version for 'next@${{ matrix.version_spec.selector }}' is '$NODE_VERSION'"
 
+      - name: Decide default bundler
+        id: decide-default-bundler
+        shell: bash
+        run: |
+          # we run tests with default bundler for given Next.js version
+          # some tests have webpack/turbopack specific assertions or skips
+          # so we need to set IS_WEBPACK_TEST, IS_TURBOPACK_TEST env vars accordingly
+          # to ensure tests assert behavior of the default bundler
+          DEFAULT_BUNDLER="webpack"
+          if [ "${{ matrix.version_spec.selector }}" = "canary" ]; then
+            # this is not ideal, because we set turbopack default just when explicitly using canary tag as target
+            # but next@canary are still on 15 major, so we can't yet use major version of resolved next version
+            # as condition
+            DEFAULT_BUNDLER="turbopack"
+          fi
+          echo "default_bundler=$DEFAULT_BUNDLER" >> $GITHUB_OUTPUT
+          echo "Default bundler for 'next@${{ matrix.version_spec.selector }}' is '$DEFAULT_BUNDLER'"
+
       - name: setup node
         uses: actions/setup-node@v5
         with:
@@ -218,6 +236,9 @@ jobs:
           # one job may wait for deploys in other jobs (only one deploy may be in progress for
           # a given alias at a time), resulting in cascading timeouts.
           DEPLOY_ALIAS: vercel-next-e2e-${{ matrix.version_spec.selector }}-${{ matrix.group }}
+          NEXT_RESOLVED_VERSION: ${{ matrix.version_spec.version }}
+          IS_WEBPACK_TEST: ${{ steps.decide-default-bundler.outputs.default_bundler == 'webpack' && '1' || '' }}
+          IS_TURBOPACK_TEST: ${{ steps.decide-default-bundler.outputs.default_bundler == 'turbopack' && '1' || '' }}
         run: node run-tests.js -g ${{ matrix.group }}/${{ needs.setup.outputs.total }} -c ${TEST_CONCURRENCY} --type e2e
         working-directory: ${{ env.next-path }}
 
@@ -226,7 +247,7 @@ jobs:
         uses: actions/upload-artifact@v4
         with:
           name: test-result-${{matrix.version_spec.selector}}-${{ matrix.group }}
-          path: ${{ env.next-path }}/test/test-junit-report/*.xml
+          path: ${{ env.next-path }}/test/${{steps.decide-default-bundler.outputs.default_bundler == 'turbopack' && 'turbopack-test-junit-report' || 'test-junit-report'}}/*.xml
   publish-test-results:
     name: 'E2E Test Summary (${{matrix.version_spec.selector}})'
     needs:

tests/netlify-deploy.ts

@@ -4,6 +4,7 @@ import fs from 'fs-extra'
 import { Span } from 'next/src/trace'
 import { tmpdir } from 'node:os'
 import path from 'path'
+import { satisfies as satisfiesVersionRange } from 'semver'
 import { NextInstance } from './base'
 
 async function packNextRuntimeImpl() {
@@ -58,6 +59,34 @@ export class NextDeployInstance extends NextInstance {
 
     const setupStartTime = Date.now()
 
+    const { runtimePackageName, runtimePackageTarballPath } = await packNextRuntime()
+
+    this.dependencies = {
+      ...(this.dependencies || {}),
+      // add the runtime package as a dependency
+      [runtimePackageName]: `file:${runtimePackageTarballPath}`,
+    }
+
+    if (
+      typeof this.files === 'string' &&
+      this.files.includes('back-forward-cache') &&
+      process.env.NEXT_RESOLVED_VERSION &&
+      satisfiesVersionRange(process.env.NEXT_RESOLVED_VERSION, '<=15.5.4')
+    ) {
+      require('console').log('Pinning @types/react(-dom) for back-forward-cache test fixture')
+      // back-forward-cache test fixture is failing types checking because:
+      //   - @types/react(-dom) types are not pinned
+      //   - fixture uses react `unstable_Activity` export which since fixture was introduced is no longer unstable
+      //     and types were updated for that and no longer provide types for that export (instead provide for `Activity`)
+      //     this adds the pinning of types to version of types that still had `unstable_Activity` type
+      this.dependencies['@types/react'] = '19.1.1'
+      this.dependencies['@types/react-dom'] = '19.1.2'
+    }
+
+    if (!this.buildCommand && this.buildArgs && this.buildArgs.length > 0) {
+      this.buildCommand = `next build ${this.buildArgs.join(' ')}`
+    }
+
     // create the test site
     await super.createTestDir({ parentSpan, skipInstall: true })
 
@@ -70,10 +99,13 @@ export class NextDeployInstance extends NextInstance {
       await fs.rename(nodeModules, nodeModulesBak)
     }
 
-    const { runtimePackageName, runtimePackageTarballPath } = await packNextRuntime()
-
     // install dependencies
-    await execa('npm', ['i', runtimePackageTarballPath, '--legacy-peer-deps'], {
+    // --force is used to match behavior of `pnpm install --strict-peer-dependencies=false` used by Vercel
+    // there is a test fixture that have `@babel/preset-flow` as a dependency which has a peer dependency of `@babel/core@^7.0.0-0`,
+    // but `@babel/core` is not specified as dependency, so we need to automatically attempt to install peer dependencies
+    // but also not fail in case of peer dependency versions not matching for other fixtures, so `--legacy-peer-deps` is not good option here
+    // https://github.com/vercel/next.js/blob/7453d200579512a6574f9c53edd716e5cc01615c/test/e2e/babel/index.test.js#L7-L9
+    await execa('npm', ['install', '--force'], {
       cwd: this.testDir,
       stdio: 'inherit',
     })