Revert "Use Xcode legacy build system for iOS builds (#21901)" (#21966)

This caused issues for projects without an Xcode workspace. Almost all
Flutter projects in the wild will have a workspace, but this patch needs
to add a check to catch any that lack one.

This reverts commit 021f472e.

packages/flutter_tools/lib/src/context_runner.dart

@@ -71,7 +71,6 @@ Future<T> runInContext<T>(
       KernelCompiler: () => const KernelCompiler(),
       Logger: () => platform.isWindows ? WindowsStdoutLogger() : StdoutLogger(),
       OperatingSystemUtils: () => OperatingSystemUtils(),
-      PlistBuddy: () => const PlistBuddy(),
       SimControl: () => SimControl(),
       Stdio: () => const Stdio(),
       Usage: () => Usage(),

packages/flutter_tools/lib/src/ios/mac.dart

@@ -32,56 +32,8 @@ const int kXcodeRequiredVersionMajor = 9;
 const int kXcodeRequiredVersionMinor = 0;
 
 IMobileDevice get iMobileDevice => context[IMobileDevice];
-PlistBuddy get plistBuddy => context[PlistBuddy];
-Xcode get xcode => context[Xcode];
-
-class PlistBuddy {
-  const PlistBuddy();
-
-  static const String path = '/usr/libexec/PlistBuddy';
-
-  Future<ProcessResult> run(List<String> args) => processManager.run(<String>[path]..addAll(args));
-}
-
-/// A property list is a key-value representation commonly used for
-/// configuration on macOS/iOS systems.
-class PropertyList {
-  const PropertyList(this.plistPath);
-
-  final String plistPath;
-
-  /// Prints the specified key, or returns null if not present.
-  Future<String> read(String key) async {
-    final ProcessResult result = await _runCommand('Print $key');
-    if (result.exitCode == 0)
-      return result.stdout.trim();
-    return null;
-  }
-
-  /// Adds [key]. Has no effect if the key already exists.
-  Future<void> addString(String key, String value) async {
-    await _runCommand('Add $key string $value');
-  }
-
-  /// Updates [key] with the new [value]. Has no effect if the key does not exist.
-  Future<void> update(String key, String value) async {
-    await _runCommand('Set $key $value');
-  }
-
-  /// Deletes [key].
-  Future<void> delete(String key) async {
-    await _runCommand('Delete $key');
-  }
 
-  /// Deletes the content of the property list and creates a new root of the specified type.
-  Future<void> clearToDict() async {
-    await _runCommand('Clear dict');
-  }
-
-  Future<ProcessResult> _runCommand(String command) async {
-    return await plistBuddy.run(<String>['-c', command, plistPath]);
-  }
-}
+Xcode get xcode => context[Xcode];
 
 class IMobileDevice {
   const IMobileDevice();
@@ -229,41 +181,6 @@ class Xcode {
   }
 }
 
-/// Sets the Xcode system.
-///
-/// Xcode 10 added a new (default) build system with better performance and
-/// stricter checks. Flutter apps without plugins build fine under the new
-/// system, but it causes build breakages in projects with CocoaPods enabled.
-/// This affects Flutter apps with plugins.
-///
-/// Once Flutter has been updated to be fully compliant with the new build
-/// system, this can be removed.
-//
-// TODO(cbracken): remove when https://github.com/flutter/flutter/issues/20685 is fixed.
-Future<void> setXcodeWorkspaceBuildSystem({
-  @required File workspaceSettings,
-  @required bool modern,
-}) async {
-  final PropertyList plist = PropertyList(workspaceSettings.path);
-  if (!workspaceSettings.existsSync()) {
-    workspaceSettings.parent.createSync(recursive: true);
-    await plist.clearToDict();
-  }
-
-  const String kBuildSystemType = 'BuildSystemType';
-  if (modern) {
-    printTrace('Using new Xcode build system.');
-    await plist.delete(kBuildSystemType);
-  } else {
-    printTrace('Using legacy Xcode build system.');
-    if (await plist.read(kBuildSystemType) == null) {
-      await plist.addString(kBuildSystemType, 'Original');
-    } else {
-      await plist.update(kBuildSystemType, 'Original');
-    }
-  }
-}
-
 Future<XcodeBuildResult> buildXcodeProject({
   BuildableIOSApp app,
   BuildInfo buildInfo,
@@ -278,12 +195,6 @@ Future<XcodeBuildResult> buildXcodeProject({
   if (!_checkXcodeVersion())
     return XcodeBuildResult(success: false);
 
-  // TODO(cbracken) remove when https://github.com/flutter/flutter/issues/20685 is fixed.
-  await setXcodeWorkspaceBuildSystem(
-    workspaceSettings: app.project.xcodeWorkspaceSharedSettings,
-    modern: false,
-  );
-
   final XcodeProjectInfo projectInfo = xcodeProjectInterpreter.getInfo(app.project.directory.path);
   if (!projectInfo.targets.contains('Runner')) {
     printError('The Xcode project does not define target "Runner" which is needed by Flutter tooling.');

packages/flutter_tools/lib/src/project.dart

@@ -186,15 +186,6 @@ class IosProject {
   /// The '.pbxproj' file of the host app.
   File get xcodeProjectInfoFile => xcodeProject.childFile('project.pbxproj');
 
-  /// Xcode workspace directory of the host app.
-  Directory get xcodeWorkspace => directory.childDirectory('$_hostAppBundleName.xcworkspace');
-
-  /// Xcode workspace shared data directory for the host app.
-  Directory get xcodeWorkspaceSharedData => xcodeWorkspace.childDirectory('xcshareddata');
-
-  /// Xcode workspace shared workspace settings file for the host app.
-  File get xcodeWorkspaceSharedSettings => xcodeWorkspaceSharedData.childFile('WorkspaceSettings.xcsettings');
-
   /// The product bundle identifier of the host app, or null if not set or if
   /// iOS tooling needed to read it is not installed.
   String get productBundleIdentifier {

packages/flutter_tools/test/ios/mac_test.dart

@@ -5,7 +5,6 @@
 import 'dart:async';
 
 import 'package:file/file.dart';
-import 'package:file/memory.dart';
 import 'package:flutter_tools/src/base/file_system.dart';
 import 'package:flutter_tools/src/base/io.dart' show ProcessException, ProcessResult;
 import 'package:flutter_tools/src/ios/mac.dart';
@@ -22,63 +21,6 @@ class MockFile extends Mock implements File {}
 class MockXcodeProjectInterpreter extends Mock implements XcodeProjectInterpreter {}
 
 void main() {
-  group('PropertyList', () {
-    MockProcessManager mockProcessManager;
-    MemoryFileSystem fs;
-    File workspaceSettingsFile;
-
-    setUp(() {
-      mockProcessManager = MockProcessManager();
-      fs = MemoryFileSystem();
-      workspaceSettingsFile = fs.file('WorkspaceSettings.xcsettings');
-    });
-
-    testUsingContext('creates dict-based plist if settings file does not exist', () async {
-      workspaceSettingsFile.parent.createSync(recursive: true);
-      when(mockProcessManager.run(<String>[PlistBuddy.path, '-c', 'Print BuildSystemType', workspaceSettingsFile.path]))
-        .thenAnswer((_) => Future<ProcessResult>.value(ProcessResult(1, 1, '', '')));
-      await setXcodeWorkspaceBuildSystem(workspaceSettings: workspaceSettingsFile, modern: false);
-      verify(mockProcessManager.run(<String>[PlistBuddy.path, '-c', 'Clear dict', workspaceSettingsFile.path]));
-      verify(mockProcessManager.run(<String>[PlistBuddy.path, '-c', 'Add BuildSystemType string Original', workspaceSettingsFile.path]));
-    }, overrides: <Type, Generator>{
-      FileSystem: () => fs,
-      ProcessManager: () => mockProcessManager,
-    });
-
-    testUsingContext('writes legacy build mode settings if requested and not present', () async {
-      workspaceSettingsFile.createSync();
-      when(mockProcessManager.run(<String>[PlistBuddy.path, '-c', 'Print BuildSystemType', workspaceSettingsFile.path]))
-        .thenAnswer((_) => Future<ProcessResult>.value(ProcessResult(1, 1, '', '')));
-      await setXcodeWorkspaceBuildSystem(workspaceSettings: workspaceSettingsFile, modern: false);
-      verify(mockProcessManager.run(<String>[PlistBuddy.path, '-c', 'Add BuildSystemType string Original', workspaceSettingsFile.path]));
-    }, overrides: <Type, Generator>{
-      FileSystem: () => fs,
-      ProcessManager: () => mockProcessManager,
-    });
-
-    testUsingContext('updates legacy build mode setting if requested and existing setting is present', () async {
-      workspaceSettingsFile.createSync();
-      when(mockProcessManager.run(<String>[PlistBuddy.path, '-c', 'Print BuildSystemType', workspaceSettingsFile.path]))
-        .thenAnswer((_) => Future<ProcessResult>.value(ProcessResult(1, 0, 'FancyNewOne', '')));
-      await setXcodeWorkspaceBuildSystem(workspaceSettings: workspaceSettingsFile, modern: false);
-      verify(mockProcessManager.run(<String>[PlistBuddy.path, '-c', 'Set BuildSystemType Original', workspaceSettingsFile.path]));
-    }, overrides: <Type, Generator>{
-      FileSystem: () => fs,
-      ProcessManager: () => mockProcessManager,
-    });
-
-    testUsingContext('deletes legacy build mode setting if modern build mode requested', () async {
-      workspaceSettingsFile.createSync();
-      when(mockProcessManager.run(<String>[PlistBuddy.path, '-c', 'Print BuildSystemType', workspaceSettingsFile.path]))
-        .thenAnswer((_) => Future<ProcessResult>.value(ProcessResult(1, 0, 'Original', '')));
-      await setXcodeWorkspaceBuildSystem(workspaceSettings: workspaceSettingsFile, modern: true);
-      verify(mockProcessManager.run(<String>[PlistBuddy.path, '-c', 'Delete BuildSystemType', workspaceSettingsFile.path]));
-    }, overrides: <Type, Generator>{
-      FileSystem: () => fs,
-      ProcessManager: () => mockProcessManager,
-    });
-  });
-
   group('IMobileDevice', () {
     final FakePlatform osx = FakePlatform.fromPlatform(const LocalPlatform())
       ..operatingSystem = 'macos';