Improve collection node testing, reveal double-load issue. #trivial

AsyncDisplayKit.xcodeproj/project.pbxproj

@@ -371,6 +371,8 @@
 		CCA282D11E9EBF6C0037E8B7 /* ASTipsWindow.m in Sources */ = {isa = PBXBuildFile; fileRef = CCA282CF1E9EBF6C0037E8B7 /* ASTipsWindow.m */; };
 		CCA5F62C1EEC9E9B0060C137 /* NSInvocation+ASTestHelpers.m in Sources */ = {isa = PBXBuildFile; fileRef = CCA5F62B1EEC9E9B0060C137 /* NSInvocation+ASTestHelpers.m */; };
 		CCB2F34D1D63CCC6004E6DE9 /* ASDisplayNodeSnapshotTests.m in Sources */ = {isa = PBXBuildFile; fileRef = CCB2F34C1D63CCC6004E6DE9 /* ASDisplayNodeSnapshotTests.m */; };
+		CCB338E41EEE11160081F21A /* OCMockObject+ASAdditions.m in Sources */ = {isa = PBXBuildFile; fileRef = CCB338E31EEE11160081F21A /* OCMockObject+ASAdditions.m */; };
+		CCB338E71EEE27760081F21A /* ASTestCase.m in Sources */ = {isa = PBXBuildFile; fileRef = CCB338E61EEE27760081F21A /* ASTestCase.m */; };
 		CCBBBF5D1EB161760069AA91 /* ASRangeManagingNode.h in Headers */ = {isa = PBXBuildFile; fileRef = CCBBBF5C1EB161760069AA91 /* ASRangeManagingNode.h */; settings = {ATTRIBUTES = (Public, ); }; };
 		CCCCCCD51EC3EF060087FE10 /* ASTextDebugOption.h in Headers */ = {isa = PBXBuildFile; fileRef = CCCCCCC31EC3EF060087FE10 /* ASTextDebugOption.h */; };
 		CCCCCCD61EC3EF060087FE10 /* ASTextDebugOption.m in Sources */ = {isa = PBXBuildFile; fileRef = CCCCCCC41EC3EF060087FE10 /* ASTextDebugOption.m */; };
@@ -392,6 +394,7 @@
 		CCCCCCE81EC3F0FC0087FE10 /* NSAttributedString+ASText.m in Sources */ = {isa = PBXBuildFile; fileRef = CCCCCCE61EC3F0FC0087FE10 /* NSAttributedString+ASText.m */; };
 		CCD523111EBD658C001F2191 /* ASTextNode2.h in Headers */ = {isa = PBXBuildFile; fileRef = CCD5230F1EBD658C001F2191 /* ASTextNode2.h */; };
 		CCD523121EBD658C001F2191 /* ASTextNode2.mm in Sources */ = {isa = PBXBuildFile; fileRef = CCD523101EBD658C001F2191 /* ASTextNode2.mm */; };
+		CCDD148B1EEDCD9D0020834E /* ASCollectionModernDataSourceTests.m in Sources */ = {isa = PBXBuildFile; fileRef = CCDD148A1EEDCD9D0020834E /* ASCollectionModernDataSourceTests.m */; };
 		CCF18FF41D2575E300DF5895 /* NSIndexSet+ASHelpers.h in Headers */ = {isa = PBXBuildFile; fileRef = CC4981BA1D1C7F65004E13CC /* NSIndexSet+ASHelpers.h */; settings = {ATTRIBUTES = (Private, ); }; };
 		DB55C2671C641AE4004EDCF5 /* ASContextTransitioning.h in Headers */ = {isa = PBXBuildFile; fileRef = DB55C2651C641AE4004EDCF5 /* ASContextTransitioning.h */; settings = {ATTRIBUTES = (Public, ); }; };
 		DB7121BCD50849C498C886FB /* libPods-AsyncDisplayKitTests.a in Frameworks */ = {isa = PBXBuildFile; fileRef = EFA731F0396842FF8AB635EE /* libPods-AsyncDisplayKitTests.a */; };
@@ -829,6 +832,10 @@
 		CCA5F62A1EEC9E9B0060C137 /* NSInvocation+ASTestHelpers.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = "NSInvocation+ASTestHelpers.h"; sourceTree = "<group>"; };
 		CCA5F62B1EEC9E9B0060C137 /* NSInvocation+ASTestHelpers.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = "NSInvocation+ASTestHelpers.m"; sourceTree = "<group>"; };
 		CCB2F34C1D63CCC6004E6DE9 /* ASDisplayNodeSnapshotTests.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = ASDisplayNodeSnapshotTests.m; sourceTree = "<group>"; };
+		CCB338E21EEE11160081F21A /* OCMockObject+ASAdditions.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = "OCMockObject+ASAdditions.h"; sourceTree = "<group>"; };
+		CCB338E31EEE11160081F21A /* OCMockObject+ASAdditions.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = "OCMockObject+ASAdditions.m"; sourceTree = "<group>"; };
+		CCB338E51EEE27760081F21A /* ASTestCase.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = ASTestCase.h; sourceTree = "<group>"; };
+		CCB338E61EEE27760081F21A /* ASTestCase.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = ASTestCase.m; sourceTree = "<group>"; };
 		CCBBBF5C1EB161760069AA91 /* ASRangeManagingNode.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = ASRangeManagingNode.h; sourceTree = "<group>"; };
 		CCBD05DE1E4147B000D18509 /* ASIGListAdapterBasedDataSource.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = ASIGListAdapterBasedDataSource.m; sourceTree = "<group>"; };
 		CCBD05DF1E4147B000D18509 /* ASIGListAdapterBasedDataSource.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = ASIGListAdapterBasedDataSource.h; sourceTree = "<group>"; };
@@ -852,6 +859,7 @@
 		CCCCCCE61EC3F0FC0087FE10 /* NSAttributedString+ASText.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = "NSAttributedString+ASText.m"; sourceTree = "<group>"; };
 		CCD5230F1EBD658C001F2191 /* ASTextNode2.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = ASTextNode2.h; sourceTree = "<group>"; };
 		CCD523101EBD658C001F2191 /* ASTextNode2.mm */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.objcpp; path = ASTextNode2.mm; sourceTree = "<group>"; };
+		CCDD148A1EEDCD9D0020834E /* ASCollectionModernDataSourceTests.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = ASCollectionModernDataSourceTests.m; sourceTree = "<group>"; };
 		CCE04B1E1E313EA7006AEBBB /* ASSectionController.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = ASSectionController.h; sourceTree = "<group>"; };
 		CCE04B201E313EB9006AEBBB /* IGListAdapter+AsyncDisplayKit.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = "IGListAdapter+AsyncDisplayKit.h"; sourceTree = "<group>"; };
 		CCE04B211E313EB9006AEBBB /* IGListAdapter+AsyncDisplayKit.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = "IGListAdapter+AsyncDisplayKit.m"; sourceTree = "<group>"; };
@@ -1107,8 +1115,13 @@
 		058D09C5195D04C000B7D73C /* Tests */ = {
 			isa = PBXGroup;
 			children = (
+				CCB338E51EEE27760081F21A /* ASTestCase.h */,
+				CCB338E61EEE27760081F21A /* ASTestCase.m */,
+				CCB338E21EEE11160081F21A /* OCMockObject+ASAdditions.h */,
+				CCB338E31EEE11160081F21A /* OCMockObject+ASAdditions.m */,
 				CCA5F62A1EEC9E9B0060C137 /* NSInvocation+ASTestHelpers.h */,
 				CCA5F62B1EEC9E9B0060C137 /* NSInvocation+ASTestHelpers.m */,
+				CCDD148A1EEDCD9D0020834E /* ASCollectionModernDataSourceTests.m */,
 				CC034A0F1E60C9BF00626263 /* ASRectTableTests.m */,
 				CC11F9791DB181180024D77B /* ASNetworkImageNodeTests.m */,
 				CC051F1E1D7A286A006434CB /* ASCALayerTests.m */,
@@ -2050,6 +2063,7 @@
 				CC4981B31D1A02BE004E13CC /* ASTableViewThrashTests.m in Sources */,
 				CC54A81E1D7008B300296A24 /* ASDispatchTests.m in Sources */,
 				058D0A3B195D057000B7D73C /* ASDisplayNodeTestsHelper.m in Sources */,
+				CCB338E71EEE27760081F21A /* ASTestCase.m in Sources */,
 				83A7D95E1D446A6E00BF333E /* ASWeakMapTests.m in Sources */,
 				056D21551ABCEF50001107EF /* ASImageNodeSnapshotTests.m in Sources */,
 				AC026B581BD3F61800BBC17E /* ASAbsoluteLayoutSpecSnapshotTests.m in Sources */,
@@ -2060,12 +2074,14 @@
 				058D0A3C195D057000B7D73C /* ASMutableAttributedStringBuilderTests.m in Sources */,
 				CC8B05D81D73979700F54286 /* ASTextNodePerformanceTests.m in Sources */,
 				697B315A1CFE4B410049936F /* ASEditableTextNodeTests.m in Sources */,
+				CCB338E41EEE11160081F21A /* OCMockObject+ASAdditions.m in Sources */,
 				ACF6ED611B178DC700DA7C62 /* ASOverlayLayoutSpecSnapshotTests.mm in Sources */,
 				CC8B05D61D73836400F54286 /* ASPerformanceTestContext.m in Sources */,
 				CC0AEEA41D66316E005D1C78 /* ASUICollectionViewTests.m in Sources */,
 				69B225671D72535E00B25B22 /* ASDisplayNodeLayoutTests.mm in Sources */,
 				ACF6ED621B178DC700DA7C62 /* ASRatioLayoutSpecSnapshotTests.mm in Sources */,
 				7AB338691C55B97B0055FDE8 /* ASRelativeLayoutSpecSnapshotTests.mm in Sources */,
+				CCDD148B1EEDCD9D0020834E /* ASCollectionModernDataSourceTests.m in Sources */,
 				254C6B541BF8FF2A003EC431 /* ASTextKitTests.mm in Sources */,
 				05EA6FE71AC0966E00E35788 /* ASSnapshotTestCase.m in Sources */,
 				ACF6ED631B178DC700DA7C62 /* ASStackLayoutSpecSnapshotTests.mm in Sources */,

Source/ASCollectionView.mm

@@ -1647,7 +1647,7 @@ - (ASCellNodeBlock)dataController:(ASDataController *)dataController nodeBlockAt
         return cell;
       };
     } else {
-      ASDisplayNodeFailAssert(@"ASCollection could not get a node block for row at index path %@: %@, %@. If you are trying to display a UICollectionViewCell, make sure your dataSource conforms to the <ASCollectionDataSourceInterop> protocol!", indexPath, cell, block);
+      ASDisplayNodeFailAssert(@"ASCollection could not get a node block for item at index path %@: %@, %@. If you are trying to display a UICollectionViewCell, make sure your dataSource conforms to the <ASCollectionDataSourceInterop> protocol!", indexPath, cell, block);
       block = ^{
         return [[ASCellNode alloc] init];
       };

Tests/ASCollectionModernDataSourceTests.m

@@ -0,0 +1,106 @@
+//
+//  ASCollectionModernDataSourceTests.m
+//  Texture
+//
+//  Copyright (c) 2017-present, Pinterest, Inc.  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
+//
+
+#import <XCTest/XCTest.h>
+#import <OCMock/OCMock.h>
+#import <AsyncDisplayKit/AsyncDisplayKit.h>
+#import <AsyncDisplayKit/NSIndexSet+ASHelpers.h>
+#import "OCMockObject+ASAdditions.h"
+#import "ASTestCase.h"
+
+@interface ASCollectionModernDataSourceTests : ASTestCase
+
+@end
+
+@implementation ASCollectionModernDataSourceTests {
+@private
+  id mockDataSource;
+  UIWindow *window;
+  UIViewController *viewController;
+  ASCollectionNode *collectionNode;
+}
+
+- (void)setUp {
+  [super setUp];
+  window = [[UIWindow alloc] initWithFrame:CGRectMake(0, 0, 100, 100)];
+  viewController = [[UIViewController alloc] init];
+
+  window.rootViewController = viewController;
+  [window makeKeyAndVisible];
+  collectionNode = [[ASCollectionNode alloc] initWithCollectionViewLayout:[UICollectionViewFlowLayout new]];
+  collectionNode.frame = viewController.view.bounds;
+  collectionNode.view.autoresizingMask = UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight;
+  [viewController.view addSubnode:collectionNode];
+
+  mockDataSource = OCMStrictProtocolMock(@protocol(ASCollectionDataSource));
+  [mockDataSource addImplementedOptionalProtocolMethods:
+   @selector(numberOfSectionsInCollectionNode:),
+   @selector(collectionNode:numberOfItemsInSection:),
+   @selector(collectionNode:nodeBlockForItemAtIndexPath:),
+   nil];
+  [mockDataSource setExpectationOrderMatters:YES];
+
+  // NOTE: Adding optionally-implemented methods after this point won't work due to ASCollectionNode selector caching.
+  collectionNode.dataSource = mockDataSource;
+}
+
+- (void)tearDown
+{
+  OCMVerifyAll(mockDataSource);
+  [super tearDown];
+}
+
+- (void)testInitialDataLoadingCallPattern
+{
+  /// BUG: these methods are called twice in a row i.e. this for-loop shouldn't be here. https://github.com/TextureGroup/Texture/issues/351
+  for (int i = 0; i < 2; i++) {
+    NSArray *counts = @[ @2 ];
+    [self expectDataSourceMethodsWithCounts:counts];
+  }
+
+  [window layoutIfNeeded];
+}
+
+#pragma mark - Helpers
+
+/**
+ * Adds expectations for the sequence:
+ *
+ * numberOfSectionsInCollectionNode:
+ * for section in countsArray
+ *  numberOfItemsInSection:
+ *  for item < itemCount
+ *    nodeBlockForItemAtIndexPath:
+ */
+- (void)expectDataSourceMethodsWithCounts:(NSArray<NSNumber *> *)counts
+{
+  // -numberOfSectionsInCollectionNode
+  OCMExpect([mockDataSource numberOfSectionsInCollectionNode:collectionNode])
+  .andReturn(counts.count);
+
+  // For each section:
+  // Note: Skip fast enumeration for readability.
+  for (NSInteger section = 0; section < counts.count; section++) {
+    NSInteger itemCount = counts[section].integerValue;
+    OCMExpect([mockDataSource collectionNode:collectionNode numberOfItemsInSection:section])
+    .andReturn(itemCount);
+
+    // For each item:
+    for (NSInteger i = 0; i < itemCount; i++) {
+      NSIndexPath *indexPath = [NSIndexPath indexPathForItem:i inSection:section];
+      OCMExpect([mockDataSource collectionNode:collectionNode nodeBlockForItemAtIndexPath:indexPath])
+      .andReturn((ASCellNodeBlock)^{ return [[ASCellNode alloc] init]; });
+    }
+  }
+}
+
+@end

Tests/ASTestCase.h

@@ -0,0 +1,17 @@
+//
+//  ASTestCase.h
+//  Texture
+//
+//  Copyright (c) 2017-present, Pinterest, Inc.  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
+//
+
+#import <XCTest/XCTest.h>
+
+@interface ASTestCase : XCTestCase
+
+@end

Tests/ASTestCase.m

@@ -0,0 +1,50 @@
+//
+//  ASTestCase.m
+//  Texture
+//
+//  Copyright (c) 2017-present, Pinterest, Inc.  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
+//
+
+#import "ASTestCase.h"
+#import <objc/runtime.h>
+
+@implementation ASTestCase
+
+- (void)tearDown
+{
+  // Clear out all application windows. Note: the system will retain these sometimes on its
+  // own but we'll do our best.
+  for (UIWindow *window in [UIApplication sharedApplication].windows) {
+    [window resignKeyWindow];
+    window.hidden = YES;
+    for (UIView *view in window.subviews) {
+      [view removeFromSuperview];
+    }
+  }
+
+  // Set nil for all our subclasses' ivars. Use setValue:forKey: so memory is managed correctly.
+  Class c = [self class];
+  while (c != [ASTestCase class]) {
+    unsigned int ivarCount;
+    Ivar *ivars = class_copyIvarList(c, &ivarCount);
+    for (unsigned int i = 0; i < ivarCount; i++) {
+      Ivar ivar = ivars[i];
+      NSString *key = [NSString stringWithCString:ivar_getName(ivar) encoding:NSUTF8StringEncoding];
+      [self setValue:nil forKey:key];
+    }
+    if (ivars) {
+      free(ivars);
+    }
+
+    c = [c superclass];
+  }
+
+  [super tearDown];
+}
+
+@end

Tests/OCMockObject+ASAdditions.h

@@ -0,0 +1,29 @@
+//
+//  OCMockObject+ASAdditions.h
+//  Texture
+//
+//  Copyright (c) 2017-present, Pinterest, Inc.  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
+//
+
+#import <OCMock/OCMockObject.h>
+
+@interface OCMockObject (ASAdditions)
+
+/**
+ * A method to manually specify which optional protocol methods should return YES
+ * from -respondsToSelector:.
+ *
+ * If you don't call this method, the default OCMock behavior is to
+ * "implement" all optional protocol methods, which makes it impossible to
+ * test scenarios where only a subset of optional protocol methods are implemented.
+ *
+ * You should only call this on protocol mocks.
+ */
+- (void)addImplementedOptionalProtocolMethods:(SEL)aSelector, ... NS_REQUIRES_NIL_TERMINATION;
+
+@end