Include -isysroot -arch and -miphoneos-version-min when creating dummy module...

Include -isysroot -arch and -miphoneos-version-min when creating dummy module App.framework (#97689)

dev/devicelab/bin/tasks/module_test_ios.dart

@@ -246,6 +246,9 @@ dependencies:
       final Directory objectiveCBuildDirectory = Directory(path.join(tempDir.path, 'build-objc'));
 
       section('Build iOS Objective-C host app');
+
+      final File dummyAppFramework = File(path.join(projectDir.path, '.ios', 'Flutter', 'App.framework', 'App'));
+      checkFileNotExists(dummyAppFramework.path);
       await inDirectory(objectiveCHostApp, () async {
         await exec(
           'pod',
@@ -267,6 +270,14 @@ dependencies:
           throw TaskResult.failure('Building host app Podfile.lock does not contain expected pods');
         }
 
+        // Just running "pod install" should create a fake App.framework so CocoaPods recognizes
+        // it as a framework that needs to be embedded, before Flutter actually creates it.
+        checkFileExists(dummyAppFramework.path);
+        final String? version = await minPhoneOSVersion(dummyAppFramework.path);
+        if (version != '9.0') {
+          throw TaskResult.failure('Minimum version set to $version, expected 9.0');
+        }
+
         await exec(
           'xcodebuild',
           <String>[

dev/devicelab/lib/framework/ios.dart

@@ -16,6 +16,37 @@ Future<String> fileType(String pathToBinary) {
   return eval('file', <String>[pathToBinary]);
 }
 
+Future<String?> minPhoneOSVersion(String pathToBinary) async {
+  final String loadCommands = await eval('otool', <String>[
+    '-l',
+    '-arch',
+    'arm64',
+    pathToBinary,
+  ]);
+  if (!loadCommands.contains('LC_VERSION_MIN_IPHONEOS')) {
+    return null;
+  }
+
+  String? minVersion;
+  // Load command 7
+  // cmd LC_VERSION_MIN_IPHONEOS
+  // cmdsize 16
+  // version 9.0
+  // sdk 15.2
+  //  ...
+  final List<String> lines = LineSplitter.split(loadCommands).toList();
+  lines.asMap().forEach((int index, String line) {
+    if (line.contains('LC_VERSION_MIN_IPHONEOS') && lines.length - index - 1 > 3) {
+      final String versionLine = lines
+          .skip(index - 1)
+          .take(4).last;
+      final RegExp versionRegex = RegExp(r'\s*version\s*(\S*)');
+      minVersion = versionRegex.firstMatch(versionLine)?.group(1);
+    }
+  });
+  return minVersion;
+}
+
 Future<bool> containsBitcode(String pathToBinary) async {
   // See: https://stackoverflow.com/questions/32755775/how-to-check-a-static-library-is-built-contain-bitcode
   final String loadCommands = await eval('otool', <String>[

packages/flutter_tools/templates/module/ios/library/Flutter.tmpl/podhelper.rb.tmpl

@@ -109,7 +109,8 @@ def install_flutter_application_pod(flutter_application_path)
     # CocoaPods will not embed the framework on pod install (before any build phases can run) if the dylib does not exist.
     # Create a dummy dylib.
     FileUtils.mkdir_p(app_framework_dir)
-    `echo "static const int Moo = 88;" | xcrun clang -x c -dynamiclib -o "#{app_framework_dylib}" -`
+    sdk_path = `xcrun --sdk iphoneos --show-sdk-path`.strip
+    `echo "static const int Moo = 88;" | xcrun clang -x c -arch arm64 -dynamiclib -miphoneos-version-min=9.0 -isysroot "#{sdk_path}" -o "#{app_framework_dylib}" -`
   end
 
   # Keep pod and script phase paths relative so they can be checked into source control.