[flutter_tools] build ios-frameworks: option to exclude plugin frameworks from the build (#129739)

A lot of details are written in the feature request: https://github.com/flutter/flutter/issues/114692.

tl;dr: Options B & C from the add2app iOS guide have a limitation (build error) in case the Flutter plugin and native iOS app have a shared dependency. We can use a workaround to avoid the issue, but in this case we don't need to build frameworks for plugins.

Closes https://github.com/flutter/flutter/issues/114692
Part of https://github.com/flutter/flutter/issues/130220

dev/devicelab/bin/tasks/build_ios_framework_module_test.dart

@@ -493,6 +493,12 @@ Future<void> _testBuildIosFramework(Directory projectDir, { bool isModule = fals
       isModule) {
     throw TaskResult.failure('Unexpected GeneratedPluginRegistrant.m.');
   }
+
+  section('Build frameworks without plugins');
+  await _testBuildFrameworksWithoutPlugins(projectDir, platform: 'ios');
+
+  section('check --static cannot be used with the --no-plugins flag');
+  await _testStaticAndNoPlugins(projectDir);
 }
 
 
@@ -816,6 +822,83 @@ Future<void> _testBuildMacOSFramework(Directory projectDir) async {
     outputPath,
     'GeneratedPluginRegistrant.swift',
   ));
+
+  section('Build frameworks without plugins');
+  await _testBuildFrameworksWithoutPlugins(projectDir, platform: 'macos');
+}
+
+Future<void> _testBuildFrameworksWithoutPlugins(Directory projectDir, { required String platform}) async {
+  const String noPluginsOutputDir = 'flutter-frameworks-no-plugins';
+
+  await inDirectory(projectDir, () async {
+    await flutter(
+      'build',
+      options: <String>[
+        '$platform-framework',
+        '--cocoapods',
+        '--force', // Allow podspec creation on master.
+        '--output=$noPluginsOutputDir',
+        '--no-plugins',
+      ],
+    );
+  });
+
+  final String noPluginsOutputPath = path.join(projectDir.path, noPluginsOutputDir);
+  for (final String mode in <String>['Debug', 'Profile', 'Release']) {
+    checkFileExists(path.join(
+      noPluginsOutputPath,
+      mode,
+      'Flutter${platform == 'macos' ? 'MacOS' : ''}.podspec',
+    ));
+    checkDirectoryExists(path.join(
+      noPluginsOutputPath,
+      mode,
+      'App.xcframework',
+    ));
+
+    checkDirectoryNotExists(path.join(
+      noPluginsOutputPath,
+      mode,
+      'package_info.xcframework',
+    ));
+
+    checkDirectoryNotExists(path.join(
+      noPluginsOutputPath,
+      mode,
+      'connectivity.xcframework',
+    ));
+
+    checkDirectoryNotExists(path.join(
+      noPluginsOutputPath,
+      mode,
+      'Reachability.xcframework',
+    ));
+  }
+}
+
+Future<void> _testStaticAndNoPlugins(Directory projectDir) async {
+  const String noPluginsOutputDir = 'flutter-frameworks-no-plugins-static';
+  final ProcessResult result = await inDirectory(projectDir, () async {
+    return executeFlutter(
+        'build',
+        options: <String>[
+          'ios-framework',
+          '--cocoapods',
+          '--force', // Allow podspec creation on master.
+          '--output=$noPluginsOutputDir',
+          '--no-plugins',
+          '--static'
+        ],
+        canFail: true
+    );
+  });
+  if (result.exitCode == 0) {
+    throw TaskResult.failure('Build framework command did not exit with error as expected');
+  }
+  final String output = '${result.stdout}\n${result.stderr}';
+  if (!output.contains('--static cannot be used with the --no-plugins flag')) {
+    throw TaskResult.failure(output);
+  }
 }
 
 Future<void> _checkDylib(String pathToLibrary) async {

packages/flutter_tools/lib/src/commands/build_ios_framework.dart

@@ -68,6 +68,11 @@ abstract class BuildFrameworkCommand extends BuildSubCommand {
       ..addFlag('cocoapods',
         help: 'Produce a Flutter.podspec instead of an engine Flutter.xcframework (recommended if host app uses CocoaPods).',
       )
+      ..addFlag('plugins',
+        defaultsTo: true,
+        help: 'Whether to produce frameworks for the plugins. '
+              'This is intended for cases where plugins are already being built separately.',
+      )
       ..addFlag('static',
         help: 'Build plugins as static frameworks. Link on, but do not embed these frameworks in the existing Xcode project.',
       )
@@ -135,6 +140,10 @@ abstract class BuildFrameworkCommand extends BuildSubCommand {
     if ((await getBuildInfos()).isEmpty) {
       throwToolExit('At least one of "--debug" or "--profile", or "--release" is required.');
     }
+
+    if (!boolArg('plugins') && boolArg('static')) {
+      throwToolExit('--static cannot be used with the --no-plugins flag');
+    }
   }
 
   static Future<void> produceXCFramework(
@@ -264,7 +273,7 @@ class BuildIOSFrameworkCommand extends BuildFrameworkCommand {
 
       // Build and copy plugins.
       await processPodsIfNeeded(project.ios, getIosBuildDirectory(), buildInfo.mode);
-      if (hasPlugins(project)) {
+      if (boolArg('plugins') && hasPlugins(project)) {
         await _producePlugins(buildInfo.mode, xcodeBuildConfiguration, iPhoneBuildOutput, simulatorBuildOutput, modeDirectory);
       }
 

packages/flutter_tools/lib/src/commands/build_macos_framework.dart

@@ -91,7 +91,7 @@ class BuildMacOSFrameworkCommand extends BuildFrameworkCommand {
       // Build and copy plugins.
       final Directory buildOutput = modeDirectory.childDirectory('macos');
       await processPodsIfNeeded(project.macos, getMacOSBuildDirectory(), buildInfo.mode);
-      if (hasPlugins(project)) {
+      if (boolArg('plugins') && hasPlugins(project)) {
         await _producePlugins(xcodeBuildConfiguration, buildOutput, modeDirectory);
       }