components/Dialogs/tests/snapshot/MDCAlertControllerCustomTraitCollectionTests.m - external/github.com/material-components/material-components-ios - Git at Google

 // Copyright 2019-present the Material Components for iOS authors. All Rights Reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
 // You may obtain a copy of the License at
 //
 // http://www.apache.org/licenses/LICENSE-2.0
 //
 // Unless required by applicable law or agreed to in writing, software
 // distributed under the License is distributed on an "AS IS" BASIS,
 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 // See the License for the specific language governing permissions and
 // limitations under the License.

 #import <CoreGraphics/CoreGraphics.h>
 #import <UIKit/UIKit.h>

 #import "MDCAvailability.h"
 #import "MDCButton.h"
 #import "MDCAlertController.h"
 #import "UIFont+MaterialScalable.h"

 #pragma clang diagnostic push
 #pragma clang diagnostic ignored "-Wprivate-header"
 #import "MDCDialogShadowedView.h"
 #import "UIColor+MaterialDynamic.h"
 #import "MDCSnapshotTestCase.h"
 #import "UIView+MDCSnapshot.h"
 #pragma clang diagnostic pop

 #import "MDCAlertController+ButtonForAction.h"
 #import "MDCFontScaler.h"

 NS_ASSUME_NONNULL_BEGIN

 static NSDictionary<UIContentSizeCategory, NSNumber *> *CustomScalingCurve(void) {
   static NSDictionary<UIContentSizeCategory, NSNumber *> *scalingCurve;
   static dispatch_once_t onceToken;
   dispatch_once(&onceToken, ^{
     scalingCurve = @{
       UIContentSizeCategoryExtraSmall : @99,
       UIContentSizeCategorySmall : @98,
       UIContentSizeCategoryMedium : @97,
       UIContentSizeCategoryLarge : @96,
       UIContentSizeCategoryExtraLarge : @95,
       UIContentSizeCategoryExtraExtraLarge : @94,
       UIContentSizeCategoryExtraExtraExtraLarge : @93,
       UIContentSizeCategoryAccessibilityMedium : @92,
       UIContentSizeCategoryAccessibilityLarge : @91,
       UIContentSizeCategoryAccessibilityExtraLarge : @90,
       UIContentSizeCategoryAccessibilityExtraExtraLarge : @89,
       UIContentSizeCategoryAccessibilityExtraExtraExtraLarge : @88
     };
   });
   return scalingCurve;
 }

 /** A test fake window that allows overriding its @c traitCollection. */
 @interface MDCAlertControllerCustomTraitCollectionTestsWindowFake : UIWindow

 /** Set to override the value of @c traitCollection. */
 @property(nonatomic, strong) UITraitCollection *traitCollectionOverride;

 @end

 @implementation MDCAlertControllerCustomTraitCollectionTestsWindowFake

 - (UITraitCollection *)traitCollection {
   return self.traitCollectionOverride ?: [super traitCollection];
 }

 @end

 /**
  A @c MDCAlertController test fake to override the @c traitCollection to test for dynamic type.
  */
 @interface AlertControllerCustomTraitCollectionSnapshotTestFake : MDCAlertController
 @property(nonatomic, strong) UITraitCollection *traitCollectionOverride;
 @end

 @implementation AlertControllerCustomTraitCollectionSnapshotTestFake

 - (UITraitCollection *)traitCollection {
   return self.traitCollectionOverride ?: [super traitCollection];
 }

 @end

 /** An @c MDCDialogShadowedView test fake to override the @c traitCollection to test. */
 @interface ShadowViewCustomTraitCollectionSnapshotTestFake : MDCDialogShadowedView
 @property(nonatomic, strong) UITraitCollection *traitCollectionOverride;
 @end

 @implementation ShadowViewCustomTraitCollectionSnapshotTestFake

 - (UITraitCollection *)traitCollection {
   return self.traitCollectionOverride ?: [super traitCollection];
 }

 @end

 @interface MDCAlertControllerCustomTraitCollectionTests : MDCSnapshotTestCase
 @property(nonatomic, strong, nullable)
     AlertControllerCustomTraitCollectionSnapshotTestFake *alertController;
 @end

 @implementation MDCAlertControllerCustomTraitCollectionTests

 - (void)setUp {
   [super setUp];

   // Uncomment below to recreate all the goldens (or add the following line to the specific
   // test you wish to recreate the golden for).
   //  self.recordMode = YES;

   self.alertController = [[AlertControllerCustomTraitCollectionSnapshotTestFake alloc] init];
   self.alertController.title = @"Material";
   self.alertController.message =
       @"Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt "
       @"ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation "
       @"ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in "
       @"reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur "
       @"sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id "
       @"est laborum.";
   MDCAlertAction *fakeAction = [MDCAlertAction actionWithTitle:@"Foo"
                                                        handler:^(MDCAlertAction *action){
                                                        }];
   [self.alertController addAction:fakeAction];
   MDCFontScaler *titleFontScaler = [MDCFontScaler scalerForMaterialTextStyle:MDCTextStyleSubtitle1];
   UIFont *titleFont = [UIFont fontWithName:@"Zapfino" size:14];
   titleFont = [titleFontScaler scaledFontWithFont:titleFont];
   titleFont = [titleFont mdc_scaledFontAtDefaultSize];
   self.alertController.titleFont = titleFont;
   MDCFontScaler *messageFontScaler = [MDCFontScaler scalerForMaterialTextStyle:MDCTextStyleBody2];
   UIFont *messageFont = [UIFont fontWithName:@"Zapfino" size:14];
   messageFont = [messageFontScaler scaledFontWithFont:messageFont];
   messageFont = [messageFont mdc_scaledFontAtDefaultSize];
   self.alertController.messageFont = messageFont;
   MDCFontScaler *buttonFontScaler = [MDCFontScaler scalerForMaterialTextStyle:MDCTextStyleButton];
   UIFont *buttonFont = [UIFont fontWithName:@"Zapfino" size:14];
   buttonFont = [buttonFontScaler scaledFontWithFont:buttonFont];
   buttonFont = [buttonFont mdc_scaledFontAtDefaultSize];
   for (MDCAlertAction *action in self.alertController.actions) {
     [[self.alertController buttonForAction:action] setTitleFont:buttonFont
                                                        forState:UIControlStateNormal];
   }
   self.alertController.view.bounds = CGRectMake(0, 0, 300, 300);
 }

 - (void)tearDown {
   self.alertController = nil;

   [super tearDown];
 }

 - (void)generateSnapshotAndVerifyForView:(UIView *)view {
   [view layoutIfNeeded];
   UIView *snapshotView = [view mdc_addToBackgroundView];
   [self snapshotVerifyView:snapshotView];
 }

 /** Used to set the @c UIContentSizeCategory on an @c MDCAlertController. */
 - (void)setAlertControllerContentSizeCategory:(UIContentSizeCategory)sizeCategory {
   UITraitCollection *traitCollection = [[UITraitCollection alloc] init];
   traitCollection =
       [UITraitCollection traitCollectionWithPreferredContentSizeCategory:sizeCategory];

   self.alertController.traitCollectionOverride = traitCollection;
 }

 #pragma mark - Dynamic Type

 /**
  Tests the original MDCTypography behavior for Dynamic Type.

  @note The output depends on the host simulator and is equal to
        @c testSystemFontScaledWhenScaledFontUnavailableForContentSizeAXXXL as a result.
  */
 - (void)testSystemFontScaledWhenScaledFontUnavailableForContentSizeExtraSmall {
   // Given

   UIFont *originalFont = [UIFont fontWithName:@"Zapfino" size:20];
   UIFontMetrics *fontMetrics = [UIFontMetrics metricsForTextStyle:UIFontTextStyleHeadline];
   self.alertController.messageFont = [fontMetrics scaledFontForFont:originalFont];
   self.alertController.titleFont = [fontMetrics scaledFontForFont:originalFont];
   for (MDCAlertAction *action in self.alertController.actions) {
     [[self.alertController buttonForAction:action] setTitleFont:originalFont
                                                        forState:UIControlStateNormal];
   }
   [self setAlertControllerContentSizeCategory:UIContentSizeCategoryExtraSmall];

   // When
   [self.alertController loadViewIfNeeded];
   self.alertController.adjustsFontForContentSizeCategory = YES;

   // Then
   [self generateSnapshotAndVerifyForView:self.alertController.view];
 }

 /**
  Tests the original MDCTypography behavior for Dynamic Type.

  @note The output depends on the host simulator and is equal to
        @c testSystemFontScaledWhenScaledFontUnavailableForContentSizeExtraSmall as a result.
  */
 - (void)testSystemFontScaledWhenScaledFontUnavailableForContentSizeAXXXL {
   // Given

   // Although the font is initialized with point size 1, the MDCTypography behavior will select
   // a fixed point size for the font at the current UIContentSizeCategory (of the host app),
   // which is not 1.
   UIFont *originalFont = [UIFont fontWithName:@"Zapfino" size:20];
   UIFontMetrics *fontMetrics = [UIFontMetrics metricsForTextStyle:UIFontTextStyleHeadline];
   self.alertController.messageFont = [fontMetrics scaledFontForFont:originalFont];
   self.alertController.titleFont = [fontMetrics scaledFontForFont:originalFont];
   for (MDCAlertAction *action in self.alertController.actions) {
     [[self.alertController buttonForAction:action] setTitleFont:originalFont
                                                        forState:UIControlStateNormal];
   }
   [self
       setAlertControllerContentSizeCategory:UIContentSizeCategoryAccessibilityExtraExtraExtraLarge];

   // When
   [self.alertController loadViewIfNeeded];
   self.alertController.adjustsFontForContentSizeCategory = YES;

   // Then
   [self generateSnapshotAndVerifyForView:self.alertController.view];
 }

 /** Tests behavior when a font generated from a FontScaler is provided. */
 - (void)testFontScalerFontScaledForContentSizeExtraSmall {
   // Given
   UIFont *originalFont = [UIFont fontWithName:@"Zapfino" size:20];
   UIFontMetrics *fontMetrics = [UIFontMetrics metricsForTextStyle:UIFontTextStyleHeadline];
   self.alertController.messageFont = [fontMetrics scaledFontForFont:originalFont];
   self.alertController.titleFont = [fontMetrics scaledFontForFont:originalFont];
   for (MDCAlertAction *action in self.alertController.actions) {
     [[self.alertController buttonForAction:action] setTitleFont:originalFont
                                                        forState:UIControlStateNormal];
   }
   [self setAlertControllerContentSizeCategory:UIContentSizeCategoryExtraSmall];

   // When
   [self.alertController loadViewIfNeeded];
   self.alertController.adjustsFontForContentSizeCategory = YES;

   // Then
   [self generateSnapshotAndVerifyForView:self.alertController.view];
 }

 /** Tests behavior when a font generated from a FontScaler is provided. */
 - (void)testFontScalerFontScaledForContentSizeAXXXL {
   // Given
   UIFont *originalFont = [UIFont fontWithName:@"Zapfino" size:1];
   // Simulates a font scaler by providing scaling curve dictionary.
   originalFont.mdc_scalingCurve = CustomScalingCurve();
   self.alertController.messageFont = originalFont;
   self.alertController.titleFont = originalFont;
   for (MDCAlertAction *action in self.alertController.actions) {
     [[self.alertController buttonForAction:action] setTitleFont:originalFont
                                                        forState:UIControlStateNormal];
   }
   [self
       setAlertControllerContentSizeCategory:UIContentSizeCategoryAccessibilityExtraExtraExtraLarge];

   // When
   [self.alertController loadViewIfNeeded];
   self.alertController.adjustsFontForContentSizeCategory = YES;

   // Then
   [self generateSnapshotAndVerifyForView:self.alertController.view];
 }

 /**
  Test that @c adjustsFontForContentSizeCategory will scale an appropriate font to a larger
  size when the preferred content size category increases.
  */
 - (void)testAdjustsFontForContentSizeUpscalesUIFontMetricsFontsForSizeCategoryAXXXL {
   // Given
   UIFontMetrics *bodyMetrics = [UIFontMetrics metricsForTextStyle:UIFontTextStyleBody];
   UITraitCollection *extraSmallTraits = [UITraitCollection
       traitCollectionWithPreferredContentSizeCategory:UIContentSizeCategoryExtraSmall];

   UIFont *titleFont = [UIFont fontWithName:@"Zapfino" size:20];
   XCTAssertNotNil(titleFont);
   titleFont = [bodyMetrics scaledFontForFont:titleFont
                compatibleWithTraitCollection:extraSmallTraits];
   self.alertController.titleFont = titleFont;

   UIFont *messageFont = [UIFont fontWithName:@"Zapfino" size:15];
   messageFont = [bodyMetrics scaledFontForFont:messageFont
                  compatibleWithTraitCollection:extraSmallTraits];
   self.alertController.messageFont = messageFont;

   UIFont *buttonFont = [UIFont fontWithName:@"Zapfino" size:20];
   buttonFont = [bodyMetrics scaledFontForFont:buttonFont
                 compatibleWithTraitCollection:extraSmallTraits];
   for (MDCAlertAction *action in self.alertController.actions) {
     MDCButton *button = [self.alertController buttonForAction:action];
     button.titleLabel.font = buttonFont;
   }

   self.alertController.adjustsFontForContentSizeCategory = YES;
   [self.alertController loadViewIfNeeded];

   // The initial size is calculated without constraints, so start the view bounds there.
   CGSize alertSize = self.alertController.preferredContentSize;
   self.alertController.view.bounds = CGRectMake(0, 0, alertSize.width, alertSize.height);

   // Create a window so the Alert's view can inherit the trait environment.
   MDCAlertControllerCustomTraitCollectionTestsWindowFake *window =
       [[MDCAlertControllerCustomTraitCollectionTestsWindowFake alloc] init];
   [window makeKeyWindow];
   window.hidden = NO;
   [window addSubview:self.alertController.view];

   // When
   window.traitCollectionOverride =
       [UITraitCollection traitCollectionWithPreferredContentSizeCategory:
                              UIContentSizeCategoryAccessibilityExtraExtraExtraLarge];
   [window traitCollectionDidChange:nil];
   // Recalculates the preferredContentSize of the AlertController.
   [self.alertController.view layoutIfNeeded];
   alertSize = self.alertController.preferredContentSize;
   window.bounds = CGRectMake(0, 0, alertSize.width, alertSize.height);
   self.alertController.view.frame = window.bounds;

   // Then
   // Can't add a UIWindow to a UIView, so just screenshot the window directly.
   [window layoutIfNeeded];
   [self snapshotVerifyView:window];
 }

 /**
  Test that @c adjustsFontForContentSizeCategory will scale an appropriate font to a
  smaller size when the preferred content size category decreases.
  */
 - (void)testAdjustsFontForContentSizeDownscalesUIFontMetricsFontsForSizeCategoryXS {
   // Given
   UIFontMetrics *bodyMetrics = [UIFontMetrics metricsForTextStyle:UIFontTextStyleBody];
   UITraitCollection *aXXXLTraits =
       [UITraitCollection traitCollectionWithPreferredContentSizeCategory:
                              UIContentSizeCategoryAccessibilityExtraExtraExtraLarge];

   UIFont *titleFont = [UIFont fontWithName:@"Zapfino" size:20];
   XCTAssertNotNil(titleFont);
   titleFont = [bodyMetrics scaledFontForFont:titleFont compatibleWithTraitCollection:aXXXLTraits];
   self.alertController.titleFont = titleFont;

   UIFont *messageFont = [UIFont fontWithName:@"Zapfino" size:15];
   messageFont = [bodyMetrics scaledFontForFont:messageFont
                  compatibleWithTraitCollection:aXXXLTraits];
   self.alertController.messageFont = messageFont;

   UIFont *buttonFont = [UIFont fontWithName:@"Zapfino" size:20];
   buttonFont = [bodyMetrics scaledFontForFont:buttonFont compatibleWithTraitCollection:aXXXLTraits];
   for (MDCAlertAction *action in self.alertController.actions) {
     MDCButton *button = [self.alertController buttonForAction:action];
     button.titleLabel.font = buttonFont;
   }

   self.alertController.adjustsFontForContentSizeCategory = YES;
   [self.alertController loadViewIfNeeded];

   // The initial size is calculated without constraints, so start the view bounds there.
   CGSize alertSize = self.alertController.preferredContentSize;
   self.alertController.view.bounds = CGRectMake(0, 0, alertSize.width, alertSize.height);

   // Create a window so the Alert's view can inherit the trait environment.
   MDCAlertControllerCustomTraitCollectionTestsWindowFake *window =
       [[MDCAlertControllerCustomTraitCollectionTestsWindowFake alloc] init];
   [window makeKeyWindow];
   window.hidden = NO;
   [window addSubview:self.alertController.view];

   // When
   window.traitCollectionOverride = [UITraitCollection
       traitCollectionWithPreferredContentSizeCategory:UIContentSizeCategoryExtraSmall];
   [window traitCollectionDidChange:nil];
   // Recalculates the preferredContentSize of the AlertController.
   [self.alertController.view layoutIfNeeded];
   alertSize = self.alertController.preferredContentSize;
   window.bounds = CGRectMake(0, 0, alertSize.width, alertSize.height);
   self.alertController.view.frame = window.bounds;

   // Then
   // Can't add a UIWindow to a UIView, so just screenshot the window directly.
   [window layoutIfNeeded];
   [self snapshotVerifyView:window];
 }

 #pragma mark - Dynamic Color

 - (void)testDynamicColorSupport {
 #if MDC_AVAILABLE_SDK_IOS(13_0)
   if (@available(iOS 13.0, *)) {
     // Given
     UIColor *titleColor = [UIColor colorWithUserInterfaceStyleDarkColor:UIColor.greenColor
                                                            defaultColor:UIColor.blackColor];
     UIColor *messageColor = [UIColor colorWithUserInterfaceStyleDarkColor:UIColor.purpleColor
                                                              defaultColor:UIColor.blackColor];
     UIColor *backgroundColor = [UIColor colorWithUserInterfaceStyleDarkColor:UIColor.blueColor
                                                                 defaultColor:UIColor.blackColor];
     self.alertController.titleColor = titleColor;
     self.alertController.messageColor = messageColor;
     self.alertController.backgroundColor = backgroundColor;

     // When
     self.alertController.traitCollectionOverride =
         [UITraitCollection traitCollectionWithUserInterfaceStyle:UIUserInterfaceStyleDark];

     // Then
     UIView *snapshotView = [self.alertController.view
         mdc_addToBackgroundViewWithInsets:UIEdgeInsetsMake(50, 50, 50, 50)];
     [self snapshotVerifyViewForIOS13:snapshotView];
   }
 #endif  // MDC_AVAILABLE_SDK_IOS(13_0)
 }

 - (void)testDynamicColorSupportForTrackingView {
 #if MDC_AVAILABLE_SDK_IOS(13_0)
   if (@available(iOS 13.0, *)) {
     // Given
     UIColor *shadowColor = [UIColor colorWithUserInterfaceStyleDarkColor:UIColor.greenColor
                                                             defaultColor:UIColor.blackColor];
     ShadowViewCustomTraitCollectionSnapshotTestFake *trackingView =
         [[ShadowViewCustomTraitCollectionSnapshotTestFake alloc] init];
     trackingView.frame = CGRectMake(0, 0, 100, 200);
     trackingView.shadowColor = shadowColor;
     trackingView.backgroundColor = UIColor.whiteColor;

     // When
     trackingView.traitCollectionOverride =
         [UITraitCollection traitCollectionWithUserInterfaceStyle:UIUserInterfaceStyleDark];
     [trackingView layoutIfNeeded];

     // Then
     UIView *snapshotView =
         [trackingView mdc_addToBackgroundViewWithInsets:UIEdgeInsetsMake(50, 50, 50, 50)];
     [self snapshotVerifyViewForIOS13:snapshotView];
   }
 #endif  // MDC_AVAILABLE_SDK_IOS(13_0)
 }

 @end

 NS_ASSUME_NONNULL_END
	// Copyright 2019-present the Material Components for iOS authors. All Rights Reserved.
	//
	// Licensed under the Apache License, Version 2.0 (the "License");
	// you may not use this file except in compliance with the License.
	// You may obtain a copy of the License at
	//
	// http://www.apache.org/licenses/LICENSE-2.0
	//
	// Unless required by applicable law or agreed to in writing, software
	// distributed under the License is distributed on an "AS IS" BASIS,
	// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	// See the License for the specific language governing permissions and
	// limitations under the License.

	#import <CoreGraphics/CoreGraphics.h>
	#import <UIKit/UIKit.h>

	#import "MDCAvailability.h"
	#import "MDCButton.h"
	#import "MDCAlertController.h"
	#import "UIFont+MaterialScalable.h"

	#pragma clang diagnostic push
	#pragma clang diagnostic ignored "-Wprivate-header"
	#import "MDCDialogShadowedView.h"
	#import "UIColor+MaterialDynamic.h"
	#import "MDCSnapshotTestCase.h"
	#import "UIView+MDCSnapshot.h"
	#pragma clang diagnostic pop

	#import "MDCAlertController+ButtonForAction.h"
	#import "MDCFontScaler.h"

	NS_ASSUME_NONNULL_BEGIN

	static NSDictionary<UIContentSizeCategory, NSNumber > CustomScalingCurve(void) {
	static NSDictionary<UIContentSizeCategory, NSNumber > scalingCurve;
	static dispatch_once_t onceToken;
	dispatch_once(&onceToken, ^{
	scalingCurve = @{
	UIContentSizeCategoryExtraSmall : @99,
	UIContentSizeCategorySmall : @98,
	UIContentSizeCategoryMedium : @97,
	UIContentSizeCategoryLarge : @96,
	UIContentSizeCategoryExtraLarge : @95,
	UIContentSizeCategoryExtraExtraLarge : @94,
	UIContentSizeCategoryExtraExtraExtraLarge : @93,
	UIContentSizeCategoryAccessibilityMedium : @92,
	UIContentSizeCategoryAccessibilityLarge : @91,
	UIContentSizeCategoryAccessibilityExtraLarge : @90,
	UIContentSizeCategoryAccessibilityExtraExtraLarge : @89,
	UIContentSizeCategoryAccessibilityExtraExtraExtraLarge : @88
	};
	});
	return scalingCurve;
	}

	/** A test fake window that allows overriding its @c traitCollection. */
	@interface MDCAlertControllerCustomTraitCollectionTestsWindowFake : UIWindow

	/** Set to override the value of @c traitCollection. */
	@property(nonatomic, strong) UITraitCollection *traitCollectionOverride;

	@end

	@implementation MDCAlertControllerCustomTraitCollectionTestsWindowFake

	- (UITraitCollection *)traitCollection {
	return self.traitCollectionOverride ?: [super traitCollection];
	}

	@end

	/**
	A @c MDCAlertController test fake to override the @c traitCollection to test for dynamic type.
	*/
	@interface AlertControllerCustomTraitCollectionSnapshotTestFake : MDCAlertController
	@property(nonatomic, strong) UITraitCollection *traitCollectionOverride;
	@end

	@implementation AlertControllerCustomTraitCollectionSnapshotTestFake

	- (UITraitCollection *)traitCollection {
	return self.traitCollectionOverride ?: [super traitCollection];
	}

	@end

	/** An @c MDCDialogShadowedView test fake to override the @c traitCollection to test. */
	@interface ShadowViewCustomTraitCollectionSnapshotTestFake : MDCDialogShadowedView
	@property(nonatomic, strong) UITraitCollection *traitCollectionOverride;
	@end

	@implementation ShadowViewCustomTraitCollectionSnapshotTestFake

	- (UITraitCollection *)traitCollection {
	return self.traitCollectionOverride ?: [super traitCollection];
	}

	@end

	@interface MDCAlertControllerCustomTraitCollectionTests : MDCSnapshotTestCase
	@property(nonatomic, strong, nullable)
	AlertControllerCustomTraitCollectionSnapshotTestFake *alertController;
	@end

	@implementation MDCAlertControllerCustomTraitCollectionTests

	- (void)setUp {
	[super setUp];

	// Uncomment below to recreate all the goldens (or add the following line to the specific
	// test you wish to recreate the golden for).
	// self.recordMode = YES;

	self.alertController = [[AlertControllerCustomTraitCollectionSnapshotTestFake alloc] init];
	self.alertController.title = @"Material";
	self.alertController.message =
	@"Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt "
	@"ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation "
	@"ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in "
	@"reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur "
	@"sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id "
	@"est laborum.";
	MDCAlertAction *fakeAction = [MDCAlertAction actionWithTitle:@"Foo"
	handler:^(MDCAlertAction *action){
	}];
	[self.alertController addAction:fakeAction];
	MDCFontScaler *titleFontScaler = [MDCFontScaler scalerForMaterialTextStyle:MDCTextStyleSubtitle1];
	UIFont *titleFont = [UIFont fontWithName:@"Zapfino" size:14];
	titleFont = [titleFontScaler scaledFontWithFont:titleFont];
	titleFont = [titleFont mdc_scaledFontAtDefaultSize];
	self.alertController.titleFont = titleFont;
	MDCFontScaler *messageFontScaler = [MDCFontScaler scalerForMaterialTextStyle:MDCTextStyleBody2];
	UIFont *messageFont = [UIFont fontWithName:@"Zapfino" size:14];
	messageFont = [messageFontScaler scaledFontWithFont:messageFont];
	messageFont = [messageFont mdc_scaledFontAtDefaultSize];
	self.alertController.messageFont = messageFont;
	MDCFontScaler *buttonFontScaler = [MDCFontScaler scalerForMaterialTextStyle:MDCTextStyleButton];
	UIFont *buttonFont = [UIFont fontWithName:@"Zapfino" size:14];
	buttonFont = [buttonFontScaler scaledFontWithFont:buttonFont];
	buttonFont = [buttonFont mdc_scaledFontAtDefaultSize];
	for (MDCAlertAction *action in self.alertController.actions) {
	[[self.alertController buttonForAction:action] setTitleFont:buttonFont
	forState:UIControlStateNormal];
	}
	self.alertController.view.bounds = CGRectMake(0, 0, 300, 300);
	}

	- (void)tearDown {
	self.alertController = nil;

	[super tearDown];
	}

	- (void)generateSnapshotAndVerifyForView:(UIView *)view {
	[view layoutIfNeeded];
	UIView *snapshotView = [view mdc_addToBackgroundView];
	[self snapshotVerifyView:snapshotView];
	}

	/** Used to set the @c UIContentSizeCategory on an @c MDCAlertController. */
	- (void)setAlertControllerContentSizeCategory:(UIContentSizeCategory)sizeCategory {
	UITraitCollection *traitCollection = [[UITraitCollection alloc] init];
	traitCollection =
	[UITraitCollection traitCollectionWithPreferredContentSizeCategory:sizeCategory];

	self.alertController.traitCollectionOverride = traitCollection;
	}

	#pragma mark - Dynamic Type

	/**
	Tests the original MDCTypography behavior for Dynamic Type.

	@note The output depends on the host simulator and is equal to
	@c testSystemFontScaledWhenScaledFontUnavailableForContentSizeAXXXL as a result.
	*/
	- (void)testSystemFontScaledWhenScaledFontUnavailableForContentSizeExtraSmall {
	// Given

	UIFont *originalFont = [UIFont fontWithName:@"Zapfino" size:20];
	UIFontMetrics *fontMetrics = [UIFontMetrics metricsForTextStyle:UIFontTextStyleHeadline];
	self.alertController.messageFont = [fontMetrics scaledFontForFont:originalFont];
	self.alertController.titleFont = [fontMetrics scaledFontForFont:originalFont];
	for (MDCAlertAction *action in self.alertController.actions) {
	[[self.alertController buttonForAction:action] setTitleFont:originalFont
	forState:UIControlStateNormal];
	}
	[self setAlertControllerContentSizeCategory:UIContentSizeCategoryExtraSmall];

	// When
	[self.alertController loadViewIfNeeded];
	self.alertController.adjustsFontForContentSizeCategory = YES;

	// Then
	[self generateSnapshotAndVerifyForView:self.alertController.view];
	}

	/**
	Tests the original MDCTypography behavior for Dynamic Type.

	@note The output depends on the host simulator and is equal to
	@c testSystemFontScaledWhenScaledFontUnavailableForContentSizeExtraSmall as a result.
	*/
	- (void)testSystemFontScaledWhenScaledFontUnavailableForContentSizeAXXXL {
	// Given

	// Although the font is initialized with point size 1, the MDCTypography behavior will select
	// a fixed point size for the font at the current UIContentSizeCategory (of the host app),
	// which is not 1.
	UIFont *originalFont = [UIFont fontWithName:@"Zapfino" size:20];
	UIFontMetrics *fontMetrics = [UIFontMetrics metricsForTextStyle:UIFontTextStyleHeadline];
	self.alertController.messageFont = [fontMetrics scaledFontForFont:originalFont];
	self.alertController.titleFont = [fontMetrics scaledFontForFont:originalFont];
	for (MDCAlertAction *action in self.alertController.actions) {
	[[self.alertController buttonForAction:action] setTitleFont:originalFont
	forState:UIControlStateNormal];
	}
	[self
	setAlertControllerContentSizeCategory:UIContentSizeCategoryAccessibilityExtraExtraExtraLarge];

	// When
	[self.alertController loadViewIfNeeded];
	self.alertController.adjustsFontForContentSizeCategory = YES;

	// Then
	[self generateSnapshotAndVerifyForView:self.alertController.view];
	}

	/** Tests behavior when a font generated from a FontScaler is provided. */
	- (void)testFontScalerFontScaledForContentSizeExtraSmall {
	// Given
	UIFont *originalFont = [UIFont fontWithName:@"Zapfino" size:20];
	UIFontMetrics *fontMetrics = [UIFontMetrics metricsForTextStyle:UIFontTextStyleHeadline];
	self.alertController.messageFont = [fontMetrics scaledFontForFont:originalFont];
	self.alertController.titleFont = [fontMetrics scaledFontForFont:originalFont];
	for (MDCAlertAction *action in self.alertController.actions) {
	[[self.alertController buttonForAction:action] setTitleFont:originalFont
	forState:UIControlStateNormal];
	}
	[self setAlertControllerContentSizeCategory:UIContentSizeCategoryExtraSmall];

	// When
	[self.alertController loadViewIfNeeded];
	self.alertController.adjustsFontForContentSizeCategory = YES;

	// Then
	[self generateSnapshotAndVerifyForView:self.alertController.view];
	}

	/** Tests behavior when a font generated from a FontScaler is provided. */
	- (void)testFontScalerFontScaledForContentSizeAXXXL {
	// Given
	UIFont *originalFont = [UIFont fontWithName:@"Zapfino" size:1];
	// Simulates a font scaler by providing scaling curve dictionary.
	originalFont.mdc_scalingCurve = CustomScalingCurve();
	self.alertController.messageFont = originalFont;
	self.alertController.titleFont = originalFont;
	for (MDCAlertAction *action in self.alertController.actions) {
	[[self.alertController buttonForAction:action] setTitleFont:originalFont
	forState:UIControlStateNormal];
	}
	[self
	setAlertControllerContentSizeCategory:UIContentSizeCategoryAccessibilityExtraExtraExtraLarge];

	// When
	[self.alertController loadViewIfNeeded];
	self.alertController.adjustsFontForContentSizeCategory = YES;

	// Then
	[self generateSnapshotAndVerifyForView:self.alertController.view];
	}

	/**
	Test that @c adjustsFontForContentSizeCategory will scale an appropriate font to a larger
	size when the preferred content size category increases.
	*/
	- (void)testAdjustsFontForContentSizeUpscalesUIFontMetricsFontsForSizeCategoryAXXXL {
	// Given
	UIFontMetrics *bodyMetrics = [UIFontMetrics metricsForTextStyle:UIFontTextStyleBody];
	UITraitCollection *extraSmallTraits = [UITraitCollection
	traitCollectionWithPreferredContentSizeCategory:UIContentSizeCategoryExtraSmall];

	UIFont *titleFont = [UIFont fontWithName:@"Zapfino" size:20];
	XCTAssertNotNil(titleFont);
	titleFont = [bodyMetrics scaledFontForFont:titleFont
	compatibleWithTraitCollection:extraSmallTraits];
	self.alertController.titleFont = titleFont;

	UIFont *messageFont = [UIFont fontWithName:@"Zapfino" size:15];
	messageFont = [bodyMetrics scaledFontForFont:messageFont
	compatibleWithTraitCollection:extraSmallTraits];
	self.alertController.messageFont = messageFont;

	UIFont *buttonFont = [UIFont fontWithName:@"Zapfino" size:20];
	buttonFont = [bodyMetrics scaledFontForFont:buttonFont
	compatibleWithTraitCollection:extraSmallTraits];
	for (MDCAlertAction *action in self.alertController.actions) {
	MDCButton *button = [self.alertController buttonForAction:action];
	button.titleLabel.font = buttonFont;
	}

	self.alertController.adjustsFontForContentSizeCategory = YES;
	[self.alertController loadViewIfNeeded];

	// The initial size is calculated without constraints, so start the view bounds there.
	CGSize alertSize = self.alertController.preferredContentSize;
	self.alertController.view.bounds = CGRectMake(0, 0, alertSize.width, alertSize.height);

	// Create a window so the Alert's view can inherit the trait environment.
	MDCAlertControllerCustomTraitCollectionTestsWindowFake *window =
	[[MDCAlertControllerCustomTraitCollectionTestsWindowFake alloc] init];
	[window makeKeyWindow];
	window.hidden = NO;
	[window addSubview:self.alertController.view];

	// When
	window.traitCollectionOverride =
	[UITraitCollection traitCollectionWithPreferredContentSizeCategory:
	UIContentSizeCategoryAccessibilityExtraExtraExtraLarge];
	[window traitCollectionDidChange:nil];
	// Recalculates the preferredContentSize of the AlertController.
	[self.alertController.view layoutIfNeeded];
	alertSize = self.alertController.preferredContentSize;
	window.bounds = CGRectMake(0, 0, alertSize.width, alertSize.height);
	self.alertController.view.frame = window.bounds;

	// Then
	// Can't add a UIWindow to a UIView, so just screenshot the window directly.
	[window layoutIfNeeded];
	[self snapshotVerifyView:window];
	}

	/**
	Test that @c adjustsFontForContentSizeCategory will scale an appropriate font to a
	smaller size when the preferred content size category decreases.
	*/
	- (void)testAdjustsFontForContentSizeDownscalesUIFontMetricsFontsForSizeCategoryXS {
	// Given
	UIFontMetrics *bodyMetrics = [UIFontMetrics metricsForTextStyle:UIFontTextStyleBody];
	UITraitCollection *aXXXLTraits =
	[UITraitCollection traitCollectionWithPreferredContentSizeCategory:
	UIContentSizeCategoryAccessibilityExtraExtraExtraLarge];

	UIFont *titleFont = [UIFont fontWithName:@"Zapfino" size:20];
	XCTAssertNotNil(titleFont);
	titleFont = [bodyMetrics scaledFontForFont:titleFont compatibleWithTraitCollection:aXXXLTraits];
	self.alertController.titleFont = titleFont;

	UIFont *messageFont = [UIFont fontWithName:@"Zapfino" size:15];
	messageFont = [bodyMetrics scaledFontForFont:messageFont
	compatibleWithTraitCollection:aXXXLTraits];
	self.alertController.messageFont = messageFont;

	UIFont *buttonFont = [UIFont fontWithName:@"Zapfino" size:20];
	buttonFont = [bodyMetrics scaledFontForFont:buttonFont compatibleWithTraitCollection:aXXXLTraits];
	for (MDCAlertAction *action in self.alertController.actions) {
	MDCButton *button = [self.alertController buttonForAction:action];
	button.titleLabel.font = buttonFont;
	}

	self.alertController.adjustsFontForContentSizeCategory = YES;
	[self.alertController loadViewIfNeeded];

	// The initial size is calculated without constraints, so start the view bounds there.
	CGSize alertSize = self.alertController.preferredContentSize;
	self.alertController.view.bounds = CGRectMake(0, 0, alertSize.width, alertSize.height);

	// Create a window so the Alert's view can inherit the trait environment.
	MDCAlertControllerCustomTraitCollectionTestsWindowFake *window =
	[[MDCAlertControllerCustomTraitCollectionTestsWindowFake alloc] init];
	[window makeKeyWindow];
	window.hidden = NO;
	[window addSubview:self.alertController.view];

	// When
	window.traitCollectionOverride = [UITraitCollection
	traitCollectionWithPreferredContentSizeCategory:UIContentSizeCategoryExtraSmall];
	[window traitCollectionDidChange:nil];
	// Recalculates the preferredContentSize of the AlertController.
	[self.alertController.view layoutIfNeeded];
	alertSize = self.alertController.preferredContentSize;
	window.bounds = CGRectMake(0, 0, alertSize.width, alertSize.height);
	self.alertController.view.frame = window.bounds;

	// Then
	// Can't add a UIWindow to a UIView, so just screenshot the window directly.
	[window layoutIfNeeded];
	[self snapshotVerifyView:window];
	}

	#pragma mark - Dynamic Color

	- (void)testDynamicColorSupport {
	#if MDC_AVAILABLE_SDK_IOS(13_0)
	if (@available(iOS 13.0, *)) {
	// Given
	UIColor *titleColor = [UIColor colorWithUserInterfaceStyleDarkColor:UIColor.greenColor
	defaultColor:UIColor.blackColor];
	UIColor *messageColor = [UIColor colorWithUserInterfaceStyleDarkColor:UIColor.purpleColor
	defaultColor:UIColor.blackColor];
	UIColor *backgroundColor = [UIColor colorWithUserInterfaceStyleDarkColor:UIColor.blueColor
	defaultColor:UIColor.blackColor];
	self.alertController.titleColor = titleColor;
	self.alertController.messageColor = messageColor;
	self.alertController.backgroundColor = backgroundColor;

	// When
	self.alertController.traitCollectionOverride =
	[UITraitCollection traitCollectionWithUserInterfaceStyle:UIUserInterfaceStyleDark];

	// Then
	UIView *snapshotView = [self.alertController.view
	mdc_addToBackgroundViewWithInsets:UIEdgeInsetsMake(50, 50, 50, 50)];
	[self snapshotVerifyViewForIOS13:snapshotView];
	}
	#endif // MDC_AVAILABLE_SDK_IOS(13_0)
	}

	- (void)testDynamicColorSupportForTrackingView {
	#if MDC_AVAILABLE_SDK_IOS(13_0)
	if (@available(iOS 13.0, *)) {
	// Given
	UIColor *shadowColor = [UIColor colorWithUserInterfaceStyleDarkColor:UIColor.greenColor
	defaultColor:UIColor.blackColor];
	ShadowViewCustomTraitCollectionSnapshotTestFake *trackingView =
	[[ShadowViewCustomTraitCollectionSnapshotTestFake alloc] init];
	trackingView.frame = CGRectMake(0, 0, 100, 200);
	trackingView.shadowColor = shadowColor;
	trackingView.backgroundColor = UIColor.whiteColor;

	// When
	trackingView.traitCollectionOverride =
	[UITraitCollection traitCollectionWithUserInterfaceStyle:UIUserInterfaceStyleDark];
	[trackingView layoutIfNeeded];

	// Then
	UIView *snapshotView =
	[trackingView mdc_addToBackgroundViewWithInsets:UIEdgeInsetsMake(50, 50, 50, 50)];
	[self snapshotVerifyViewForIOS13:snapshotView];
	}
	#endif // MDC_AVAILABLE_SDK_IOS(13_0)
	}

	@end

	NS_ASSUME_NONNULL_END