[macOS] Implement regular window (flutter#176361)

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---------

Co-authored-by: Matthew Kosarek <matt.kosarek@canonical.com>

Author: knopp

.ci.yaml

@@ -7005,6 +7005,16 @@ targets:
         ["devicelab", "hostonly", "linux"]
       task_name: windowing_test_linux
 
+  - name: MacOS windowing_test
+    recipe: devicelab/devicelab_drone
+    presubmit: true
+    bringup: true
+    timeout: 60
+    properties:
+      tags: >
+        ["devicelab", "hostonly", "macos"]
+      task_name: windowing_test_macos
+
 
   - name: Windows flutter_tool_startup__windows
     recipe: devicelab/devicelab_drone

TESTOWNERS

@@ -306,6 +306,7 @@
 /dev/devicelab/bin/tasks/windows_home_scroll_perf__timeline_summary.dart @jonahwilliams @flutter/engine
 /dev/devicelab/bin/tasks/windows_startup_test.dart @loic-sharma @flutter/desktop
 /dev/devicelab/bin/tasks/windowing_test_linux.dart @robert-ancell @flutter/desktop
+/dev/devicelab/bin/tasks/windowing_test_macos.dart @knopp @flutter/desktop
 /dev/devicelab/bin/tasks/windowing_test_windows.dart @mattkae @flutter/desktop
 /dev/devicelab/bin/tasks/mac_desktop_impeller.dart @jonahwilliams @flutter/engine
 /dev/devicelab/bin/tasks/linux_desktop_impeller.dart @jonahwilliams @flutter/engine

dev/devicelab/bin/tasks/windowing_test_macos.dart

@@ -0,0 +1,12 @@
+// Copyright 2014 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+import 'package:flutter_devicelab/framework/devices.dart';
+import 'package:flutter_devicelab/framework/framework.dart';
+import 'package:flutter_devicelab/tasks/integration_tests.dart';
+
+Future<void> main() async {
+  deviceOperatingSystem = DeviceOperatingSystem.macos;
+  await task(createWindowingDriverTest());
+}

dev/integration_tests/windowing_test/lib/main.dart

@@ -8,6 +8,7 @@ import 'dart:async';
 import 'dart:convert';
 import 'dart:io';
 
+import 'package:flutter/foundation.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter/src/widgets/_window.dart';
 import 'package:flutter_driver/driver_extension.dart';
@@ -56,6 +57,14 @@ void main() {
         controller.addListener(notificationHandler);
 
         act();
+
+        // On macOS, the predicate is immediately true, even though
+        // the animation is in progress and next request for state change
+        // will be ignored. Easiest way to handle this is to just wait.
+        if (defaultTargetPlatform == TargetPlatform.macOS) {
+          await Future.delayed(Duration(seconds: 1));
+        }
+
         await for (final _ in streamController.stream) {
           if (predicate()) {
             break;

dev/integration_tests/windowing_test/macos/.gitignore

@@ -0,0 +1,7 @@
+# Flutter-related
+**/Flutter/ephemeral/
+**/Pods/
+
+# Xcode-related
+**/dgph
+**/xcuserdata/

dev/integration_tests/windowing_test/macos/Flutter/Flutter-Debug.xcconfig

@@ -0,0 +1,2 @@
+#include? "Pods/Target Support Files/Pods-Runner/Pods-Runner.debug.xcconfig"
+#include "ephemeral/Flutter-Generated.xcconfig"

dev/integration_tests/windowing_test/macos/Flutter/Flutter-Release.xcconfig

@@ -0,0 +1,2 @@
+#include? "Pods/Target Support Files/Pods-Runner/Pods-Runner.release.xcconfig"
+#include "ephemeral/Flutter-Generated.xcconfig"

dev/integration_tests/windowing_test/macos/Podfile

@@ -0,0 +1,39 @@
+platform :osx, '10.15'
+
+# CocoaPods analytics sends network stats synchronously affecting flutter build latency.
+ENV['COCOAPODS_DISABLE_STATS'] = 'true'
+
+project 'Runner', {
+  'Debug' => :debug,
+  'Profile' => :release,
+  'Release' => :release,
+}
+
+def flutter_root
+  generated_xcode_build_settings_path = File.expand_path(File.join('..', 'Flutter', 'ephemeral', 'Flutter-Generated.xcconfig'), __FILE__)
+  unless File.exist?(generated_xcode_build_settings_path)
+    raise "#{generated_xcode_build_settings_path} must exist. If you're running pod install manually, make sure \"flutter pub get\" is executed first"
+  end
+
+  File.foreach(generated_xcode_build_settings_path) do |line|
+    matches = line.match(/FLUTTER_ROOT\=(.*)/)
+    return matches[1].strip if matches
+  end
+  raise "FLUTTER_ROOT not found in #{generated_xcode_build_settings_path}. Try deleting Flutter-Generated.xcconfig, then run \"flutter pub get\""
+end
+
+require File.expand_path(File.join('packages', 'flutter_tools', 'bin', 'podhelper'), flutter_root)
+
+flutter_macos_podfile_setup
+
+target 'Runner' do
+  use_frameworks!
+
+  flutter_install_all_macos_pods File.dirname(File.realpath(__FILE__))
+end
+
+post_install do |installer|
+  installer.pods_project.targets.each do |target|
+    flutter_additional_macos_build_settings(target)
+  end
+end