ci(e2e-ios): metro/brew caches; skip xcodebuild via app cache + JS inject

Three independent cuts to the remaining wall-clock:

- Metro transform cache persisted to .metro-cache and actions/cache.
  Content-addressed, so staleness only costs hit rate; shared by the 4
  ppk bundles in prepare and the base-app bundling inside xcodebuild.
  Measured locally: prepare 120s cold -> 52s warm.
- Homebrew download cache for applesimutils + ccache bottles.
- The built .app (plus hermesc, copied out of Pods after the build) is
  cached keyed on every native input: both ios projects, cpp/, the
  android/jni sources the podspec compiles, podspec/configs, and the
  dependency lockfile. On an exact hit pod install and detox build are
  skipped entirely and scripts/refresh-ios-app-bundle.sh re-injects the
  current JS (metro bundle + hermesc, replicating react-native-xcode.sh
  release flags) into the cached app — simulator apps don't enforce
  code signatures. No restore-keys on purpose: a partial hit would be
  the wrong binary. Verified on-device: injected app passes the full
  suite 2/2, including a JS-only API-semantics change picked up with no
  xcodebuild.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

Author: sunnylqm

.github/workflows/e2e_ios.yml

@@ -95,6 +95,15 @@ jobs:
             echo "no matching simulator found, skipping pre-boot"
           fi
 
+      - name: Cache Homebrew downloads
+        # bottle 按 URL 内容寻址,restore-keys 前缀命中即省下载(装/链接照常)
+        uses: actions/cache@v5.0.4
+        with:
+          path: ~/Library/Caches/Homebrew
+          key: ${{ runner.os }}-brew-e2e-${{ github.sha }}
+          restore-keys: |
+            ${{ runner.os }}-brew-e2e-
+
       - name: Install applesimutils and ccache
         run: brew trust wix/brew && HOMEBREW_NO_AUTO_UPDATE=1 brew install wix/brew/applesimutils ccache
 
@@ -127,6 +136,15 @@ jobs:
       - name: Install react-native-update-cli dependencies
         run: cd react-native-update-cli && bun install --frozen-lockfile && bun run build
 
+      - name: Cache Metro transform cache
+        # 内容寻址(等价 ccache 之于 clang):陈旧条目只影响命中率不影响正确性
+        uses: actions/cache@v5.0.4
+        with:
+          path: Example/e2etest/.metro-cache
+          key: ${{ runner.os }}-metro-e2e-${{ github.sha }}
+          restore-keys: |
+            ${{ runner.os }}-metro-e2e-
+
       - name: Prepare local update artifacts
         env:
           E2E_PLATFORM: ios
@@ -141,7 +159,20 @@ jobs:
           restore-keys: |
             ${{ runner.os }}-cocoapods-e2e-
 
+      - name: Cache built e2e app (keyed on native inputs)
+        # 命中 = native 输入(两个 ios 工程、cpp/jni、podspec、依赖锁)一字未改,
+        # 跳过 pod install + xcodebuild,只重新注入 JS bundle(见下)。
+        # 故意不设 restore-keys:部分命中就是错的二进制,宁可全量重建。
+        id: cache-ios-app
+        uses: actions/cache@v5.0.4
+        with:
+          path: |
+            Example/e2etest/ios/build/Build/Products/Release-iphonesimulator/AwesomeProject.app
+            Example/e2etest/ios/build/hermesc
+          key: ${{ runner.os }}-e2e-app-xcode-26.4-${{ hashFiles('Example/e2etest/ios/**', 'Example/e2etest/package.json', 'Example/e2etest/bun.lock', 'react-native-update.podspec', 'react-native.config.js', 'expo-module.config.json', 'ios/**', 'cpp/**', 'android/jni/**') }}
+
       - name: Install CocoaPods dependencies
+        if: steps.cache-ios-app.outputs.cache-hit != 'true'
         # USE_CCACHE=1 让 react_native_post_install 给所有 pod target 接上
         # RN 自带的 ccache 编译器包装脚本
         run: cd Example/e2etest/ios && USE_CCACHE=1 pod install
@@ -160,9 +191,17 @@ jobs:
         run: cd Example/e2etest && bunx detox build-framework-cache
 
       - name: Detox build (ios.sim.release)
+        if: steps.cache-ios-app.outputs.cache-hit != 'true'
         env:
           RNU_CLI_ROOT: ${{ github.workspace }}/react-native-update-cli
-        run: cd Example/e2etest && E2E_PLATFORM=ios bunx detox build --configuration ios.sim.release
+        run: |
+          cd Example/e2etest && E2E_PLATFORM=ios bunx detox build --configuration ios.sim.release
+          # hermesc 进缓存区:命中 run 没有 Pods,注入脚本需要它编 HBC
+          cp ios/Pods/hermes-engine/destroot/bin/hermesc ios/build/hermesc
+
+      - name: Refresh JS bundle in cached app
+        if: steps.cache-ios-app.outputs.cache-hit == 'true'
+        run: cd Example/e2etest && ./scripts/refresh-ios-app-bundle.sh
 
       - name: Detox test (ios.sim.release)
         env:

Example/e2etest/.gitignore

@@ -76,3 +76,4 @@ coverage/
 android/app/.cxx/
 *.xcresult
 result*.xml
+.metro-cache/

Example/e2etest/metro.config.js

@@ -1,11 +1,17 @@
+const path = require('path');
 const {getDefaultConfig, mergeConfig} = require('@react-native/metro-config');
+const {FileStore} = require('metro-cache');
 
 /**
  * Metro configuration
  * https://reactnative.dev/docs/metro
  *
  * @type {import('@react-native/metro-config').MetroConfig}
  */
-const config = {};
+const config = {
+  // transform cache 是内容寻址的,落到项目内固定目录让 CI 用 actions/cache
+  // 跨 run 持久化(prep 的 4 次 ppk 打包 + xcodebuild 里的基座打包共享)。
+  cacheStores: [new FileStore({root: path.join(__dirname, '.metro-cache')})],
+};
 
 module.exports = mergeConfig(getDefaultConfig(__dirname), config);

Example/e2etest/scripts/refresh-ios-app-bundle.sh

@@ -0,0 +1,39 @@
+#!/usr/bin/env bash
+#
+# 在缓存命中的 .app 里重新注入当前源码的 JS bundle + assets,跳过整个
+# pod install + xcodebuild(native 输入没变时它们只会产出同样的二进制)。
+# 复刻 react-native-xcode.sh 的 release 流程:metro bundle → hermesc
+# (-emit-binary -max-diagnostic-width=80 -O)。模拟器 app 不做签名校验,
+# 替换资源后可直接安装运行;注入结果由 e2e 套件本身验证(BINARY_BASE
+# 断言 + 完整更新流)。
+set -euo pipefail
+
+cd "$(dirname "$0")/.."
+
+APP=ios/build/Build/Products/Release-iphonesimulator/AwesomeProject.app
+# 构建后由 workflow 从 Pods/hermes-engine 拷贝进缓存区(缓存命中时无 Pods)
+HERMESC=ios/build/hermesc
+
+if [ ! -d "$APP" ]; then
+  echo "error: cached app not found: $APP" >&2
+  exit 1
+fi
+if [ ! -x "$HERMESC" ]; then
+  echo "error: cached hermesc not found: $HERMESC" >&2
+  exit 1
+fi
+
+TMP=$(mktemp -d)
+trap 'rm -rf "$TMP"' EXIT
+
+bunx react-native bundle \
+  --platform ios \
+  --dev false \
+  --entry-file index.js \
+  --bundle-output "$TMP/main.jsbundle" \
+  --assets-dest "$APP"
+
+"$HERMESC" -emit-binary -max-diagnostic-width=80 -O \
+  -out "$APP/main.jsbundle" "$TMP/main.jsbundle"
+
+echo "refreshed JS bundle in $APP"