[iOS] Load additional Cupertino system fonts

ci/licenses_golden/licenses_flutter

@@ -4032,6 +4032,7 @@ ORIGIN: ../../../flutter/third_party/txt/src/txt/platform.h + ../../../flutter/L
 ORIGIN: ../../../flutter/third_party/txt/src/txt/platform_android.cc + ../../../flutter/LICENSE
 ORIGIN: ../../../flutter/third_party/txt/src/txt/platform_fuchsia.cc + ../../../flutter/LICENSE
 ORIGIN: ../../../flutter/third_party/txt/src/txt/platform_linux.cc + ../../../flutter/LICENSE
+ORIGIN: ../../../flutter/third_party/txt/src/txt/platform_mac.h + ../../../flutter/LICENSE
 ORIGIN: ../../../flutter/third_party/txt/src/txt/platform_mac.mm + ../../../flutter/LICENSE
 ORIGIN: ../../../flutter/third_party/txt/src/txt/platform_windows.cc + ../../../flutter/LICENSE
 ORIGIN: ../../../flutter/third_party/web_test_fonts/lib/web_test_fonts.dart + ../../../flutter/LICENSE
@@ -6819,6 +6820,7 @@ FILE: ../../../flutter/third_party/txt/src/txt/platform.h
 FILE: ../../../flutter/third_party/txt/src/txt/platform_android.cc
 FILE: ../../../flutter/third_party/txt/src/txt/platform_fuchsia.cc
 FILE: ../../../flutter/third_party/txt/src/txt/platform_linux.cc
+FILE: ../../../flutter/third_party/txt/src/txt/platform_mac.h
 FILE: ../../../flutter/third_party/txt/src/txt/platform_mac.mm
 FILE: ../../../flutter/third_party/txt/src/txt/platform_windows.cc
 FILE: ../../../flutter/third_party/web_test_fonts/lib/web_test_fonts.dart

lib/ui/text/font_collection.cc

@@ -22,6 +22,9 @@
 #include "third_party/tonic/typed_data/typed_list.h"
 #include "txt/asset_font_manager.h"
 #include "txt/test_font_manager.h"
+#if FML_OS_MACOSX || FML_OS_IOS
+#include "txt/platform_mac.h"
+#endif
 
 namespace flutter {
 
@@ -63,6 +66,9 @@ void FontCollection::SetupDefaultFontManager(
 // Structure described in https://docs.flutter.dev/cookbook/design/fonts
 void FontCollection::RegisterFonts(
     const std::shared_ptr<AssetManager>& asset_manager) {
+#if FML_OS_MACOSX || FML_OS_IOS
+  RegisterSystemFonts(*dynamic_font_manager_);
+#endif
   std::unique_ptr<fml::Mapping> manifest_mapping =
       asset_manager->GetAsMapping("FontManifest.json");
   if (manifest_mapping == nullptr) {

testing/scenario_app/ios/Scenarios/Scenarios.xcodeproj/project.pbxproj

@@ -69,6 +69,8 @@
 		686383152AC2175100E27AAD /* ../../Flutter.xcframework in Frameworks */ = {isa = PBXBuildFile; fileRef = 246B4E4522E3B61000073EBF /* ../../Flutter.xcframework */; };
 		686383162AC2175100E27AAD /* ../../Flutter.xcframework in Embed Frameworks */ = {isa = PBXBuildFile; fileRef = 246B4E4522E3B61000073EBF /* ../../Flutter.xcframework */; settings = {ATTRIBUTES = (CodeSignOnCopy, RemoveHeadersOnCopy, ); }; };
 		68A5B63423EB71D300BDBCDB /* PlatformViewGestureRecognizerTests.m in Sources */ = {isa = PBXBuildFile; fileRef = 68A5B63323EB71D300BDBCDB /* PlatformViewGestureRecognizerTests.m */; };
+		68C9D8012AD9B0EF00DF9D79 /* DarwinSystemFontTests.m in Sources */ = {isa = PBXBuildFile; fileRef = 68C9D8002AD9B0EF00DF9D79 /* DarwinSystemFontTests.m */; };
+		68C9D8092AD9B6C800DF9D79 /* golden_darwin_system_font_iPhone SE (3rd generation)_16.2_simulator.png in Resources */ = {isa = PBXBuildFile; fileRef = 68C9D8082AD9B6C800DF9D79 /* golden_darwin_system_font_iPhone SE (3rd generation)_16.2_simulator.png */; };
 		68D4017D2564859300ECD91A /* ContinuousTexture.m in Sources */ = {isa = PBXBuildFile; fileRef = 68D4017C2564859300ECD91A /* ContinuousTexture.m */; };
 		68D93AEE2A46097E0054AB6D /* golden_platform_view_with_negative_backdrop_filter_iPhone SE (3rd generation)_16.2_simulator.png in Resources */ = {isa = PBXBuildFile; fileRef = 68D93AED2A46097E0054AB6D /* golden_platform_view_with_negative_backdrop_filter_iPhone SE (3rd generation)_16.2_simulator.png */; };
 		F26F15B8268B6B5600EC54D3 /* iPadGestureTests.m in Sources */ = {isa = PBXBuildFile; fileRef = F26F15B7268B6B5500EC54D3 /* iPadGestureTests.m */; };
@@ -242,6 +244,8 @@
 		686383052AC2024200E27AAD /* FlutterAppExtensionTestHost.xcodeproj */ = {isa = PBXFileReference; lastKnownFileType = "wrapper.pb-project"; name = FlutterAppExtensionTestHost.xcodeproj; path = ../FlutterAppExtensionTestHost/FlutterAppExtensionTestHost.xcodeproj; sourceTree = "<group>"; };
 		686383122AC202B700E27AAD /* AppExtensionTests.m */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.objc; path = AppExtensionTests.m; sourceTree = "<group>"; };
 		68A5B63323EB71D300BDBCDB /* PlatformViewGestureRecognizerTests.m */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.objc; path = PlatformViewGestureRecognizerTests.m; sourceTree = "<group>"; };
+		68C9D8002AD9B0EF00DF9D79 /* DarwinSystemFontTests.m */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.objc; path = DarwinSystemFontTests.m; sourceTree = "<group>"; };
+		68C9D8082AD9B6C800DF9D79 /* golden_darwin_system_font_iPhone SE (3rd generation)_16.2_simulator.png */ = {isa = PBXFileReference; lastKnownFileType = image.png; path = "golden_darwin_system_font_iPhone SE (3rd generation)_16.2_simulator.png"; sourceTree = "<group>"; };
 		68D4017B2564859300ECD91A /* ContinuousTexture.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = ContinuousTexture.h; sourceTree = "<group>"; };
 		68D4017C2564859300ECD91A /* ContinuousTexture.m */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.objc; path = ContinuousTexture.m; sourceTree = "<group>"; };
 		68D93AED2A46097E0054AB6D /* golden_platform_view_with_negative_backdrop_filter_iPhone SE (3rd generation)_16.2_simulator.png */ = {isa = PBXFileReference; lastKnownFileType = image.png; path = "golden_platform_view_with_negative_backdrop_filter_iPhone SE (3rd generation)_16.2_simulator.png"; sourceTree = "<group>"; };
@@ -366,6 +370,7 @@
 				0DDEBC88258830B40065D0E8 /* SpawnEngineTest.m */,
 				F26F15B7268B6B5500EC54D3 /* iPadGestureTests.m */,
 				686383122AC202B700E27AAD /* AppExtensionTests.m */,
+				68C9D8002AD9B0EF00DF9D79 /* DarwinSystemFontTests.m */,
 			);
 			path = ScenariosUITests;
 			sourceTree = "<group>";
@@ -401,6 +406,7 @@
 		F7B464DC2759D02B00079189 /* Goldens */ = {
 			isa = PBXGroup;
 			children = (
+				68C9D8082AD9B6C800DF9D79 /* golden_darwin_system_font_iPhone SE (3rd generation)_16.2_simulator.png */,
 				3BFD971E2A990CF40094F51B /* golden_bogus_font_text_impeller_iPhone SE (3rd generation)_16.2_simulator.png */,
 				3BFD971F2A990CF40094F51B /* golden_spawn_engine_works_impeller_iPhone SE (3rd generation)_16.2_simulator.png */,
 				68D93AED2A46097E0054AB6D /* golden_platform_view_with_negative_backdrop_filter_iPhone SE (3rd generation)_16.2_simulator.png */,
@@ -617,6 +623,7 @@
 				684FFF8729F9C10700281002 /* golden_platform_view_multiple_iPhone SE (3rd generation)_16.2_simulator.png in Resources */,
 				68D93AEE2A46097E0054AB6D /* golden_platform_view_with_negative_backdrop_filter_iPhone SE (3rd generation)_16.2_simulator.png in Resources */,
 				3BFD97202A990CF50094F51B /* golden_bogus_font_text_impeller_iPhone SE (3rd generation)_16.2_simulator.png in Resources */,
+				68C9D8092AD9B6C800DF9D79 /* golden_darwin_system_font_iPhone SE (3rd generation)_16.2_simulator.png in Resources */,
 				684FFF8D29F9C10700281002 /* golden_platform_view_large_cliprrect_iPhone SE (3rd generation)_16.2_simulator.png in Resources */,
 				684FFF8329F9C10700281002 /* golden_platform_view_transform_iPhone SE (3rd generation)_16.2_simulator.png in Resources */,
 				684FFF8B29F9C10700281002 /* golden_platform_view_clippath_iPhone SE (3rd generation)_16.2_simulator.png in Resources */,
@@ -666,6 +673,7 @@
 			files = (
 				6402EBD124147BDA00987DCB /* UnobstructedPlatformViewTests.m in Sources */,
 				68A5B63423EB71D300BDBCDB /* PlatformViewGestureRecognizerTests.m in Sources */,
+				68C9D8012AD9B0EF00DF9D79 /* DarwinSystemFontTests.m in Sources */,
 				6816DBA12317573300A51400 /* GoldenImage.m in Sources */,
 				0A02E8F724EFAD27002D54E5 /* BogusFontTextTest.m in Sources */,
 				6816DB9E231750ED00A51400 /* GoldenPlatformViewTests.m in Sources */,

testing/scenario_app/ios/Scenarios/Scenarios/AppDelegate.m

@@ -90,6 +90,7 @@ - (BOOL)application:(UIApplication*)application
     @"--two-platform-view-clip-rect" : @"two_platform_view_clip_rect",
     @"--two-platform-view-clip-rrect" : @"two_platform_view_clip_rrect",
     @"--two-platform-view-clip-path" : @"two_platform_view_clip_path",
+    @"--darwin-system-font" : @"darwin_system_font",
   };
   __block NSString* flutterViewControllerTestName = nil;
   [launchArgsMap

testing/scenario_app/ios/Scenarios/ScenariosUITests/DarwinSystemFontTests.m

@@ -0,0 +1,30 @@
+// Copyright 2013 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 <Flutter/Flutter.h>
+#import <XCTest/XCTest.h>
+#import "GoldenTestManager.h"
+
+@interface DarwinSystemFontTests : XCTestCase
+
+@end
+
+@implementation DarwinSystemFontTests
+
+- (void)testFontRendering {
+  self.continueAfterFailure = NO;
+
+  XCUIApplication* application = [[XCUIApplication alloc] init];
+  application.launchArguments = @[ @"--darwin-system-font" ];
+  [application launch];
+
+  XCUIElement* addTextField = application.textFields[@"ready"];
+  XCTAssertTrue([addTextField waitForExistenceWithTimeout:30]);
+
+  GoldenTestManager* manager =
+      [[GoldenTestManager alloc] initWithLaunchArg:@"--darwin-system-font"];
+  [manager checkGoldenForTest:self rmesThreshold:kDefaultRmseThreshold];
+}
+
+@end

testing/scenario_app/ios/Scenarios/ScenariosUITests/GoldenTestManager.m

@@ -54,6 +54,7 @@ - (instancetype)initWithLaunchArg:(NSString*)launchArg {
         @"--two-platform-view-clip-rrect" : @"two_platform_view_clip_rrect",
         @"--two-platform-view-clip-path" : @"two_platform_view_clip_path",
         @"--app-extension" : @"app_extension",
+        @"--darwin-system-font" : @"darwin_system_font",
       };
     });
     _identifier = launchArgsMap[launchArg];

testing/scenario_app/lib/src/darwin_system_font.dart

@@ -0,0 +1,62 @@
+// Copyright 2013 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 'dart:ui';
+
+import 'channel_util.dart';
+import 'scenario.dart';
+
+/// Tries to draw darwin system font: CupertinoSystemDisplay, CupertinoSystemText
+class DarwinSystemFont extends Scenario {
+  /// Creates the DarwinSystemFont scenario.
+  DarwinSystemFont(super.view);
+
+  // Semi-arbitrary.
+  final double _screenWidth = 700;
+
+  @override
+  void onBeginFrame(Duration duration) {
+    final SceneBuilder builder = SceneBuilder();
+    final PictureRecorder recorder = PictureRecorder();
+    final Canvas canvas = Canvas(recorder);
+
+    final ParagraphBuilder paragraphBuilderDisplay =
+        ParagraphBuilder(ParagraphStyle(fontFamily: 'CupertinoSystemDisplay'))
+          ..pushStyle(TextStyle(fontSize: 50))
+          ..addText('Cupertino System Display\n')
+          ..pop();
+    final ParagraphBuilder paragraphBuilderText =
+        ParagraphBuilder(ParagraphStyle(fontFamily: 'CupertinoSystemText'))
+          ..pushStyle(TextStyle(fontSize: 50))
+          ..addText('Cupertino System Text\n')
+          ..pop();
+
+    final Paragraph paragraphPro = paragraphBuilderDisplay.build();
+    paragraphPro.layout(ParagraphConstraints(width: _screenWidth));
+    canvas.drawParagraph(paragraphPro, const Offset(50, 80));
+
+    final Paragraph paragraphText = paragraphBuilderText.build();
+    paragraphText.layout(ParagraphConstraints(width: _screenWidth));
+    canvas.drawParagraph(paragraphText, const Offset(50, 200));
+
+    final Picture picture = recorder.endRecording();
+
+    builder.addPicture(
+      Offset.zero,
+      picture,
+      willChangeHint: true,
+    );
+    final Scene scene = builder.build();
+    view.render(scene);
+    scene.dispose();
+
+    sendJsonMessage(
+      dispatcher: view.platformDispatcher,
+      channel: 'display_data',
+      json: <String, dynamic>{
+        'data': 'ready',
+      },
+    );
+  }
+}

testing/scenario_app/lib/src/scenarios.dart

@@ -7,6 +7,7 @@ import 'dart:ui';
 import 'animated_color_square.dart';
 import 'bogus_font_text.dart';
 import 'darwin_app_extension_scenario.dart';
+import 'darwin_system_font.dart';
 import 'get_bitmap_scenario.dart';
 import 'initial_route_reply.dart';
 import 'locale_initialization.dart';
@@ -68,6 +69,7 @@ Map<String, _ScenarioFactory> _scenarios = <String, _ScenarioFactory>{
   'display_texture': (FlutterView view) => DisplayTexture(view),
   'get_bitmap': (FlutterView view) => GetBitmapScenario(view),
   'app_extension': (FlutterView view) => DarwinAppExtensionScenario(view),
+  'darwin_system_font': (FlutterView view) => DarwinSystemFont(view),
 };
 
 Map<String, dynamic> _currentScenarioParams = <String, dynamic>{};

third_party/txt/BUILD.gn

@@ -98,7 +98,10 @@ source_set("txt") {
   }
 
   if (is_mac || is_ios) {
-    sources += [ "src/txt/platform_mac.mm" ]
+    sources += [
+      "src/txt/platform_mac.h",
+      "src/txt/platform_mac.mm",
+    ]
     deps += [ "//flutter/fml" ]
   } else if (is_android) {
     sources += [ "src/txt/platform_android.cc" ]
@@ -148,6 +151,10 @@ if (enable_unittests) {
       "tests/txt_run_all_unittests.cc",
     ]
 
+    if (is_mac || is_ios) {
+      sources += [ "tests/platform_mac_tests.cc" ]
+    }
+
     public_configs = [ ":txt_config" ]
 
     configs += [ ":allow_posix_names" ]

third_party/txt/src/txt/asset_font_manager.h

@@ -89,7 +89,7 @@ class DynamicFontManager : public AssetFontManager {
   DynamicFontManager()
       : AssetFontManager(std::make_unique<TypefaceFontAssetProvider>()) {}
 
-  TypefaceFontAssetProvider& font_provider() {
+  TypefaceFontAssetProvider& font_provider() const {
     return static_cast<TypefaceFontAssetProvider&>(*font_provider_);
   }
 };

third_party/txt/src/txt/platform_mac.h

@@ -0,0 +1,17 @@
+// Copyright 2013 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.
+
+#ifndef TXT_PLATFORM_MAC_H_
+#define TXT_PLATFORM_MAC_H_
+
+#include "txt/asset_font_manager.h"
+
+namespace txt {
+
+// Register additional system font for MacOS and iOS.
+void RegisterSystemFonts(const DynamicFontManager& dynamic_font_manager);
+
+}  // namespace txt
+
+#endif  // TXT_PLATFORM_MAC_H_

third_party/txt/src/txt/platform_mac.mm

@@ -5,7 +5,9 @@
 #include <TargetConditionals.h>
 
 #include "flutter/fml/platform/darwin/platform_version.h"
+#include "third_party/skia/include/ports/SkTypeface_mac.h"
 #include "txt/platform.h"
+#include "txt/platform_mac.h"
 
 #if TARGET_OS_EMBEDDED || TARGET_OS_SIMULATOR
 #include <UIKit/UIKit.h>
@@ -15,6 +17,15 @@
 #define FONT_CLASS NSFont
 #endif  // TARGET_OS_EMBEDDED
 
+// Apple system font larger than size 29 returns SFProDisplay typeface.
+static const CGFloat kSFProDisplayBreakPoint = 29;
+// Apple system font smaller than size 16 returns SFProText typeface.
+static const CGFloat kSFProTextBreakPoint = 16;
+// Font name represents the "SF Pro Display" system font on Apple platforms.
+static const std::string kSFProDisplayName = "CupertinoSystemDisplay";
+// Font name represents the "SF Pro Text" system font on Apple platforms.
+static const std::string kSFProTextName = "CupertinoSystemText";
+
 namespace txt {
 
 std::vector<std::string> GetDefaultFontFamilies() {
@@ -29,4 +40,34 @@
   return SkFontMgr::RefDefault();
 }
 
+void RegisterSystemFonts(const DynamicFontManager& dynamic_font_manager) {
+  // iOS loads different system fonts when size is greater than 28 or lower
+  // than 17. The "familyName" property returned from CoreText stays the same
+  // despite the typeface is different.
+  //
+  // Below code manually loads and registers them as two different fonts
+  // so Flutter app can access them on macOS and iOS.
+  //
+  // Darwin system fonts from 17 to 28 also have dynamic spacing based on sizes.
+  // These two fonts do not match the spacings when sizes are from 17 to 28.
+  // The spacing should be handled by the app or the framework.
+  //
+  // See https://www.wwdcnotes.com/notes/wwdc20/10175/ for Apple's document on
+  // this topic.
+  sk_sp<SkTypeface> large_system_font = SkMakeTypefaceFromCTFont(
+      (CTFontRef)CFAutorelease(CTFontCreateUIFontForLanguage(
+          kCTFontUIFontSystem, kSFProDisplayBreakPoint, NULL)));
+  if (large_system_font) {
+    dynamic_font_manager.font_provider().RegisterTypeface(large_system_font,
+                                                          kSFProDisplayName);
+  }
+  sk_sp<SkTypeface> regular_system_font = SkMakeTypefaceFromCTFont(
+      (CTFontRef)CFAutorelease(CTFontCreateUIFontForLanguage(
+          kCTFontUIFontSystem, kSFProTextBreakPoint, NULL)));
+  if (regular_system_font) {
+    dynamic_font_manager.font_provider().RegisterTypeface(regular_system_font,
+                                                          kSFProTextName);
+  }
+}
+
 }  // namespace txt

third_party/txt/tests/platform_mac_tests.cc

@@ -0,0 +1,34 @@
+// Copyright 2013 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.
+
+#include "gtest/gtest.h"
+
+#include <sstream>
+
+#include "txt/platform_mac.h"
+
+namespace txt {
+namespace testing {
+
+class PlatformMacTests : public ::testing::Test {
+ public:
+  PlatformMacTests() {}
+
+  void SetUp() override {}
+};
+
+TEST_F(PlatformMacTests, RegisterSystemFonts) {
+  DynamicFontManager dynamic_font_manager;
+  RegisterSystemFonts(dynamic_font_manager);
+  ASSERT_EQ(dynamic_font_manager.font_provider().GetFamilyCount(), 2ul);
+  ASSERT_NE(dynamic_font_manager.font_provider().MatchFamily(
+                "CupertinoSystemDisplay"),
+            nullptr);
+  ASSERT_NE(
+      dynamic_font_manager.font_provider().MatchFamily("CupertinoSystemText"),
+      nullptr);
+}
+
+}  // namespace testing
+}  // namespace txt