IGListKit Support II: Electric Boogaloo (#2942)

* Reimplement IGListKit support in a cleaner way

* Rename and fix some stuff

* Fix supplementaries more

* Update docs

* Update test

* Cleanup minor things

* Tweak it

* Indentation

* Remove irrelevant changes

* Break out cell into its own file

* Fix indentation

* Address feedback

.travis.yml

@@ -17,6 +17,7 @@ before_install:
 install: echo "<3"
 env:
   - MODE=tests
+  - MODE=tests_listkit
   - MODE=examples-pt1
   - MODE=examples-pt2
   - MODE=examples-pt3

ASDKListKit/ASDKListKit.xcodeproj/project.pbxproj

@@ -0,0 +1,394 @@
+// !$*UTF8*$!
+{
+	archiveVersion = 1;
+	classes = {
+	};
+	objectVersion = 46;
+	objects = {
+
+/* Begin PBXBuildFile section */
+		BD860CAB842324FDF0B3105C /* libPods-ASDKListKitTests.a in Frameworks */ = {isa = PBXBuildFile; fileRef = 1FEACA22D54B3609C19BB4CE /* libPods-ASDKListKitTests.a */; };
+		CC5532391E16F2A90011C01F /* ASListTestSupplementarySource.m in Sources */ = {isa = PBXBuildFile; fileRef = CC55322D1E16F2A90011C01F /* ASListTestSupplementarySource.m */; };
+		CC55323A1E16F2A90011C01F /* ASListTestSupplementaryNode.m in Sources */ = {isa = PBXBuildFile; fileRef = CC55322F1E16F2A90011C01F /* ASListTestSupplementaryNode.m */; };
+		CC55323B1E16F2A90011C01F /* ASListKitTestAdapterDataSource.m in Sources */ = {isa = PBXBuildFile; fileRef = CC5532311E16F2A90011C01F /* ASListKitTestAdapterDataSource.m */; };
+		CC55323C1E16F2A90011C01F /* ASListTestSection.m in Sources */ = {isa = PBXBuildFile; fileRef = CC5532331E16F2A90011C01F /* ASListTestSection.m */; };
+		CC55323D1E16F2A90011C01F /* ASListTestCellNode.m in Sources */ = {isa = PBXBuildFile; fileRef = CC5532351E16F2A90011C01F /* ASListTestCellNode.m */; };
+		CC55323E1E16F2A90011C01F /* ASListTestObject.m in Sources */ = {isa = PBXBuildFile; fileRef = CC5532371E16F2A90011C01F /* ASListTestObject.m */; };
+		CC55323F1E16F2A90011C01F /* ASListKitTests.m in Sources */ = {isa = PBXBuildFile; fileRef = CC5532381E16F2A90011C01F /* ASListKitTests.m */; };
+/* End PBXBuildFile section */
+
+/* Begin PBXFileReference section */
+		1FEACA22D54B3609C19BB4CE /* libPods-ASDKListKitTests.a */ = {isa = PBXFileReference; explicitFileType = archive.ar; includeInIndex = 0; path = "libPods-ASDKListKitTests.a"; sourceTree = BUILT_PRODUCTS_DIR; };
+		B1FDA57F88BB590E403D7BB8 /* Pods-ASDKListKitTests.debug.xcconfig */ = {isa = PBXFileReference; includeInIndex = 1; lastKnownFileType = text.xcconfig; name = "Pods-ASDKListKitTests.debug.xcconfig"; path = "Pods/Target Support Files/Pods-ASDKListKitTests/Pods-ASDKListKitTests.debug.xcconfig"; sourceTree = "<group>"; };
+		CC5532231E16EB9D0011C01F /* ASDKListKitTests.xctest */ = {isa = PBXFileReference; explicitFileType = wrapper.cfbundle; includeInIndex = 0; path = ASDKListKitTests.xctest; sourceTree = BUILT_PRODUCTS_DIR; };
+		CC5532281E16EB9D0011C01F /* Info.plist */ = {isa = PBXFileReference; lastKnownFileType = text.plist.xml; path = Info.plist; sourceTree = "<group>"; };
+		CC55322C1E16F2A90011C01F /* ASListTestSupplementarySource.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = ASListTestSupplementarySource.h; sourceTree = "<group>"; };
+		CC55322D1E16F2A90011C01F /* ASListTestSupplementarySource.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = ASListTestSupplementarySource.m; sourceTree = "<group>"; };
+		CC55322E1E16F2A90011C01F /* ASListTestSupplementaryNode.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = ASListTestSupplementaryNode.h; sourceTree = "<group>"; };
+		CC55322F1E16F2A90011C01F /* ASListTestSupplementaryNode.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = ASListTestSupplementaryNode.m; sourceTree = "<group>"; };
+		CC5532301E16F2A90011C01F /* ASListKitTestAdapterDataSource.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = ASListKitTestAdapterDataSource.h; sourceTree = "<group>"; };
+		CC5532311E16F2A90011C01F /* ASListKitTestAdapterDataSource.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = ASListKitTestAdapterDataSource.m; sourceTree = "<group>"; };
+		CC5532321E16F2A90011C01F /* ASListTestSection.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = ASListTestSection.h; sourceTree = "<group>"; };
+		CC5532331E16F2A90011C01F /* ASListTestSection.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = ASListTestSection.m; sourceTree = "<group>"; };
+		CC5532341E16F2A90011C01F /* ASListTestCellNode.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = ASListTestCellNode.h; sourceTree = "<group>"; };
+		CC5532351E16F2A90011C01F /* ASListTestCellNode.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = ASListTestCellNode.m; sourceTree = "<group>"; };
+		CC5532361E16F2A90011C01F /* ASListTestObject.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = ASListTestObject.h; sourceTree = "<group>"; };
+		CC5532371E16F2A90011C01F /* ASListTestObject.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = ASListTestObject.m; sourceTree = "<group>"; };
+		CC5532381E16F2A90011C01F /* ASListKitTests.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = ASListKitTests.m; sourceTree = "<group>"; };
+		CC55326C1E16F67A0011C01F /* ASXCTExtensions.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = ASXCTExtensions.h; sourceTree = "<group>"; };
+		D6BDED6F23A72F40F571EEF0 /* Pods-ASDKListKitTests.release.xcconfig */ = {isa = PBXFileReference; includeInIndex = 1; lastKnownFileType = text.xcconfig; name = "Pods-ASDKListKitTests.release.xcconfig"; path = "Pods/Target Support Files/Pods-ASDKListKitTests/Pods-ASDKListKitTests.release.xcconfig"; sourceTree = "<group>"; };
+/* End PBXFileReference section */
+
+/* Begin PBXFrameworksBuildPhase section */
+		CC5532201E16EB9D0011C01F /* Frameworks */ = {
+			isa = PBXFrameworksBuildPhase;
+			buildActionMask = 2147483647;
+			files = (
+				BD860CAB842324FDF0B3105C /* libPods-ASDKListKitTests.a in Frameworks */,
+			);
+			runOnlyForDeploymentPostprocessing = 0;
+		};
+/* End PBXFrameworksBuildPhase section */
+
+/* Begin PBXGroup section */
+		72C6817154F7AC11E373624A /* Pods */ = {
+			isa = PBXGroup;
+			children = (
+				B1FDA57F88BB590E403D7BB8 /* Pods-ASDKListKitTests.debug.xcconfig */,
+				D6BDED6F23A72F40F571EEF0 /* Pods-ASDKListKitTests.release.xcconfig */,
+			);
+			name = Pods;
+			sourceTree = "<group>";
+		};
+		74DAA5F5D522433F103348B7 /* Frameworks */ = {
+			isa = PBXGroup;
+			children = (
+				1FEACA22D54B3609C19BB4CE /* libPods-ASDKListKitTests.a */,
+			);
+			name = Frameworks;
+			sourceTree = "<group>";
+		};
+		CC5532181E16EB7A0011C01F = {
+			isa = PBXGroup;
+			children = (
+				CC5532251E16EB9D0011C01F /* ASDKListKitTests */,
+				CC5532241E16EB9D0011C01F /* Products */,
+				72C6817154F7AC11E373624A /* Pods */,
+				74DAA5F5D522433F103348B7 /* Frameworks */,
+			);
+			indentWidth = 2;
+			sourceTree = "<group>";
+			tabWidth = 2;
+			usesTabs = 0;
+		};
+		CC5532241E16EB9D0011C01F /* Products */ = {
+			isa = PBXGroup;
+			children = (
+				CC5532231E16EB9D0011C01F /* ASDKListKitTests.xctest */,
+			);
+			name = Products;
+			sourceTree = "<group>";
+		};
+		CC5532251E16EB9D0011C01F /* ASDKListKitTests */ = {
+			isa = PBXGroup;
+			children = (
+				CC55326D1E16F67D0011C01F /* Common */,
+				CC55326E1E170A740011C01F /* ListKit Fixtures */,
+				CC5532381E16F2A90011C01F /* ASListKitTests.m */,
+				CC5532281E16EB9D0011C01F /* Info.plist */,
+			);
+			path = ASDKListKitTests;
+			sourceTree = "<group>";
+		};
+		CC55326D1E16F67D0011C01F /* Common */ = {
+			isa = PBXGroup;
+			children = (
+				CC55326C1E16F67A0011C01F /* ASXCTExtensions.h */,
+			);
+			name = Common;
+			sourceTree = "<group>";
+		};
+		CC55326E1E170A740011C01F /* ListKit Fixtures */ = {
+			isa = PBXGroup;
+			children = (
+				CC55322C1E16F2A90011C01F /* ASListTestSupplementarySource.h */,
+				CC55322D1E16F2A90011C01F /* ASListTestSupplementarySource.m */,
+				CC55322E1E16F2A90011C01F /* ASListTestSupplementaryNode.h */,
+				CC55322F1E16F2A90011C01F /* ASListTestSupplementaryNode.m */,
+				CC5532301E16F2A90011C01F /* ASListKitTestAdapterDataSource.h */,
+				CC5532311E16F2A90011C01F /* ASListKitTestAdapterDataSource.m */,
+				CC5532321E16F2A90011C01F /* ASListTestSection.h */,
+				CC5532331E16F2A90011C01F /* ASListTestSection.m */,
+				CC5532341E16F2A90011C01F /* ASListTestCellNode.h */,
+				CC5532351E16F2A90011C01F /* ASListTestCellNode.m */,
+				CC5532361E16F2A90011C01F /* ASListTestObject.h */,
+				CC5532371E16F2A90011C01F /* ASListTestObject.m */,
+			);
+			name = "ListKit Fixtures";
+			sourceTree = "<group>";
+		};
+/* End PBXGroup section */
+
+/* Begin PBXNativeTarget section */
+		CC5532221E16EB9D0011C01F /* ASDKListKitTests */ = {
+			isa = PBXNativeTarget;
+			buildConfigurationList = CC5532291E16EB9D0011C01F /* Build configuration list for PBXNativeTarget "ASDKListKitTests" */;
+			buildPhases = (
+				614B24BFF3DA58512D2E2147 /* [CP] Check Pods Manifest.lock */,
+				CC55321F1E16EB9D0011C01F /* Sources */,
+				CC5532201E16EB9D0011C01F /* Frameworks */,
+				CC5532211E16EB9D0011C01F /* Resources */,
+				989E6C194A1983B8B21AB82F /* [CP] Embed Pods Frameworks */,
+				876CE14CAF6A87E34577E157 /* [CP] Copy Pods Resources */,
+			);
+			buildRules = (
+			);
+			dependencies = (
+			);
+			name = ASDKListKitTests;
+			productName = ASDKListKitTests;
+			productReference = CC5532231E16EB9D0011C01F /* ASDKListKitTests.xctest */;
+			productType = "com.apple.product-type.bundle.unit-test";
+		};
+/* End PBXNativeTarget section */
+
+/* Begin PBXProject section */
+		CC5532191E16EB7A0011C01F /* Project object */ = {
+			isa = PBXProject;
+			attributes = {
+				LastUpgradeCheck = 0820;
+				TargetAttributes = {
+					CC5532221E16EB9D0011C01F = {
+						CreatedOnToolsVersion = 8.2.1;
+						ProvisioningStyle = Automatic;
+					};
+				};
+			};
+			buildConfigurationList = CC55321C1E16EB7A0011C01F /* Build configuration list for PBXProject "ASDKListKit" */;
+			compatibilityVersion = "Xcode 3.2";
+			developmentRegion = English;
+			hasScannedForEncodings = 0;
+			knownRegions = (
+				en,
+			);
+			mainGroup = CC5532181E16EB7A0011C01F;
+			productRefGroup = CC5532241E16EB9D0011C01F /* Products */;
+			projectDirPath = "";
+			projectRoot = "";
+			targets = (
+				CC5532221E16EB9D0011C01F /* ASDKListKitTests */,
+			);
+		};
+/* End PBXProject section */
+
+/* Begin PBXResourcesBuildPhase section */
+		CC5532211E16EB9D0011C01F /* Resources */ = {
+			isa = PBXResourcesBuildPhase;
+			buildActionMask = 2147483647;
+			files = (
+			);
+			runOnlyForDeploymentPostprocessing = 0;
+		};
+/* End PBXResourcesBuildPhase section */
+
+/* Begin PBXShellScriptBuildPhase section */
+		614B24BFF3DA58512D2E2147 /* [CP] Check Pods Manifest.lock */ = {
+			isa = PBXShellScriptBuildPhase;
+			buildActionMask = 2147483647;
+			files = (
+			);
+			inputPaths = (
+			);
+			name = "[CP] Check Pods Manifest.lock";
+			outputPaths = (
+			);
+			runOnlyForDeploymentPostprocessing = 0;
+			shellPath = /bin/sh;
+			shellScript = "diff \"${PODS_ROOT}/../Podfile.lock\" \"${PODS_ROOT}/Manifest.lock\" > /dev/null\nif [[ $? != 0 ]] ; then\n    cat << EOM\nerror: The sandbox is not in sync with the Podfile.lock. Run 'pod install' or update your CocoaPods installation.\nEOM\n    exit 1\nfi\n";
+			showEnvVarsInLog = 0;
+		};
+		876CE14CAF6A87E34577E157 /* [CP] Copy Pods Resources */ = {
+			isa = PBXShellScriptBuildPhase;
+			buildActionMask = 2147483647;
+			files = (
+			);
+			inputPaths = (
+			);
+			name = "[CP] Copy Pods Resources";
+			outputPaths = (
+			);
+			runOnlyForDeploymentPostprocessing = 0;
+			shellPath = /bin/sh;
+			shellScript = "\"${SRCROOT}/Pods/Target Support Files/Pods-ASDKListKitTests/Pods-ASDKListKitTests-resources.sh\"\n";
+			showEnvVarsInLog = 0;
+		};
+		989E6C194A1983B8B21AB82F /* [CP] Embed Pods Frameworks */ = {
+			isa = PBXShellScriptBuildPhase;
+			buildActionMask = 2147483647;
+			files = (
+			);
+			inputPaths = (
+			);
+			name = "[CP] Embed Pods Frameworks";
+			outputPaths = (
+			);
+			runOnlyForDeploymentPostprocessing = 0;
+			shellPath = /bin/sh;
+			shellScript = "\"${SRCROOT}/Pods/Target Support Files/Pods-ASDKListKitTests/Pods-ASDKListKitTests-frameworks.sh\"\n";
+			showEnvVarsInLog = 0;
+		};
+/* End PBXShellScriptBuildPhase section */
+
+/* Begin PBXSourcesBuildPhase section */
+		CC55321F1E16EB9D0011C01F /* Sources */ = {
+			isa = PBXSourcesBuildPhase;
+			buildActionMask = 2147483647;
+			files = (
+				CC55323E1E16F2A90011C01F /* ASListTestObject.m in Sources */,
+				CC5532391E16F2A90011C01F /* ASListTestSupplementarySource.m in Sources */,
+				CC55323D1E16F2A90011C01F /* ASListTestCellNode.m in Sources */,
+				CC55323B1E16F2A90011C01F /* ASListKitTestAdapterDataSource.m in Sources */,
+				CC55323C1E16F2A90011C01F /* ASListTestSection.m in Sources */,
+				CC55323F1E16F2A90011C01F /* ASListKitTests.m in Sources */,
+				CC55323A1E16F2A90011C01F /* ASListTestSupplementaryNode.m in Sources */,
+			);
+			runOnlyForDeploymentPostprocessing = 0;
+		};
+/* End PBXSourcesBuildPhase section */
+
+/* Begin XCBuildConfiguration section */
+		CC55321D1E16EB7A0011C01F /* Debug */ = {
+			isa = XCBuildConfiguration;
+			buildSettings = {
+			};
+			name = Debug;
+		};
+		CC55321E1E16EB7A0011C01F /* Release */ = {
+			isa = XCBuildConfiguration;
+			buildSettings = {
+			};
+			name = Release;
+		};
+		CC55322A1E16EB9D0011C01F /* Debug */ = {
+			isa = XCBuildConfiguration;
+			baseConfigurationReference = B1FDA57F88BB590E403D7BB8 /* Pods-ASDKListKitTests.debug.xcconfig */;
+			buildSettings = {
+				ALWAYS_SEARCH_USER_PATHS = NO;
+				CLANG_ANALYZER_NONNULL = YES;
+				CLANG_CXX_LANGUAGE_STANDARD = "gnu++0x";
+				CLANG_CXX_LIBRARY = "libc++";
+				CLANG_ENABLE_MODULES = YES;
+				CLANG_ENABLE_OBJC_ARC = YES;
+				CLANG_WARN_BOOL_CONVERSION = YES;
+				CLANG_WARN_CONSTANT_CONVERSION = YES;
+				CLANG_WARN_DIRECT_OBJC_ISA_USAGE = YES_ERROR;
+				CLANG_WARN_DOCUMENTATION_COMMENTS = YES;
+				CLANG_WARN_EMPTY_BODY = YES;
+				CLANG_WARN_ENUM_CONVERSION = YES;
+				CLANG_WARN_INFINITE_RECURSION = YES;
+				CLANG_WARN_INT_CONVERSION = YES;
+				CLANG_WARN_OBJC_ROOT_CLASS = YES_ERROR;
+				CLANG_WARN_SUSPICIOUS_MOVE = YES;
+				CLANG_WARN_UNREACHABLE_CODE = YES;
+				CLANG_WARN__DUPLICATE_METHOD_MATCH = YES;
+				"CODE_SIGN_IDENTITY[sdk=iphoneos*]" = "iPhone Developer";
+				COPY_PHASE_STRIP = NO;
+				DEBUG_INFORMATION_FORMAT = dwarf;
+				ENABLE_STRICT_OBJC_MSGSEND = YES;
+				ENABLE_TESTABILITY = YES;
+				GCC_C_LANGUAGE_STANDARD = gnu99;
+				GCC_DYNAMIC_NO_PIC = NO;
+				GCC_NO_COMMON_BLOCKS = YES;
+				GCC_OPTIMIZATION_LEVEL = 0;
+				GCC_PREPROCESSOR_DEFINITIONS = (
+					"DEBUG=1",
+					"$(inherited)",
+				);
+				GCC_WARN_64_TO_32_BIT_CONVERSION = YES;
+				GCC_WARN_ABOUT_RETURN_TYPE = YES_ERROR;
+				GCC_WARN_UNDECLARED_SELECTOR = YES;
+				GCC_WARN_UNINITIALIZED_AUTOS = YES_AGGRESSIVE;
+				GCC_WARN_UNUSED_FUNCTION = YES;
+				GCC_WARN_UNUSED_VARIABLE = YES;
+				INFOPLIST_FILE = ASDKListKitTests/Info.plist;
+				IPHONEOS_DEPLOYMENT_TARGET = 10.2;
+				LD_RUNPATH_SEARCH_PATHS = "$(inherited) @executable_path/Frameworks @loader_path/Frameworks";
+				MTL_ENABLE_DEBUG_INFO = YES;
+				ONLY_ACTIVE_ARCH = YES;
+				PRODUCT_BUNDLE_IDENTIFIER = asyncdisplaykit.ASDKListKitTests;
+				PRODUCT_NAME = "$(TARGET_NAME)";
+				SDKROOT = iphoneos;
+			};
+			name = Debug;
+		};
+		CC55322B1E16EB9D0011C01F /* Release */ = {
+			isa = XCBuildConfiguration;
+			baseConfigurationReference = D6BDED6F23A72F40F571EEF0 /* Pods-ASDKListKitTests.release.xcconfig */;
+			buildSettings = {
+				ALWAYS_SEARCH_USER_PATHS = NO;
+				CLANG_ANALYZER_NONNULL = YES;
+				CLANG_CXX_LANGUAGE_STANDARD = "gnu++0x";
+				CLANG_CXX_LIBRARY = "libc++";
+				CLANG_ENABLE_MODULES = YES;
+				CLANG_ENABLE_OBJC_ARC = YES;
+				CLANG_WARN_BOOL_CONVERSION = YES;
+				CLANG_WARN_CONSTANT_CONVERSION = YES;
+				CLANG_WARN_DIRECT_OBJC_ISA_USAGE = YES_ERROR;
+				CLANG_WARN_DOCUMENTATION_COMMENTS = YES;
+				CLANG_WARN_EMPTY_BODY = YES;
+				CLANG_WARN_ENUM_CONVERSION = YES;
+				CLANG_WARN_INFINITE_RECURSION = YES;
+				CLANG_WARN_INT_CONVERSION = YES;
+				CLANG_WARN_OBJC_ROOT_CLASS = YES_ERROR;
+				CLANG_WARN_SUSPICIOUS_MOVE = YES;
+				CLANG_WARN_UNREACHABLE_CODE = YES;
+				CLANG_WARN__DUPLICATE_METHOD_MATCH = YES;
+				"CODE_SIGN_IDENTITY[sdk=iphoneos*]" = "iPhone Developer";
+				COPY_PHASE_STRIP = NO;
+				DEBUG_INFORMATION_FORMAT = "dwarf-with-dsym";
+				ENABLE_NS_ASSERTIONS = NO;
+				ENABLE_STRICT_OBJC_MSGSEND = YES;
+				GCC_C_LANGUAGE_STANDARD = gnu99;
+				GCC_NO_COMMON_BLOCKS = YES;
+				GCC_WARN_64_TO_32_BIT_CONVERSION = YES;
+				GCC_WARN_ABOUT_RETURN_TYPE = YES_ERROR;
+				GCC_WARN_UNDECLARED_SELECTOR = YES;
+				GCC_WARN_UNINITIALIZED_AUTOS = YES_AGGRESSIVE;
+				GCC_WARN_UNUSED_FUNCTION = YES;
+				GCC_WARN_UNUSED_VARIABLE = YES;
+				INFOPLIST_FILE = ASDKListKitTests/Info.plist;
+				IPHONEOS_DEPLOYMENT_TARGET = 10.2;
+				LD_RUNPATH_SEARCH_PATHS = "$(inherited) @executable_path/Frameworks @loader_path/Frameworks";
+				MTL_ENABLE_DEBUG_INFO = NO;
+				PRODUCT_BUNDLE_IDENTIFIER = asyncdisplaykit.ASDKListKitTests;
+				PRODUCT_NAME = "$(TARGET_NAME)";
+				SDKROOT = iphoneos;
+				VALIDATE_PRODUCT = YES;
+			};
+			name = Release;
+		};
+/* End XCBuildConfiguration section */
+
+/* Begin XCConfigurationList section */
+		CC55321C1E16EB7A0011C01F /* Build configuration list for PBXProject "ASDKListKit" */ = {
+			isa = XCConfigurationList;
+			buildConfigurations = (
+				CC55321D1E16EB7A0011C01F /* Debug */,
+				CC55321E1E16EB7A0011C01F /* Release */,
+			);
+			defaultConfigurationIsVisible = 0;
+			defaultConfigurationName = Release;
+		};
+		CC5532291E16EB9D0011C01F /* Build configuration list for PBXNativeTarget "ASDKListKitTests" */ = {
+			isa = XCConfigurationList;
+			buildConfigurations = (
+				CC55322A1E16EB9D0011C01F /* Debug */,
+				CC55322B1E16EB9D0011C01F /* Release */,
+			);
+			defaultConfigurationIsVisible = 0;
+			defaultConfigurationName = Release;
+		};
+/* End XCConfigurationList section */
+	};
+	rootObject = CC5532191E16EB7A0011C01F /* Project object */;
+}

ASDKListKit/ASDKListKit.xcodeproj/project.xcworkspace/contents.xcworkspacedata

@@ -0,0 +1,7 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<Workspace
+   version = "1.0">
+   <FileRef
+      location = "self:ASDKListKit.xcodeproj">
+   </FileRef>
+</Workspace>

ASDKListKit/ASDKListKit.xcworkspace/contents.xcworkspacedata

@@ -0,0 +1,10 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<Workspace
+   version = "1.0">
+   <FileRef
+      location = "group:ASDKListKit.xcodeproj">
+   </FileRef>
+   <FileRef
+      location = "group:Pods/Pods.xcodeproj">
+   </FileRef>
+</Workspace>

ASDKListKit/ASDKListKitTests/ASListKitTestAdapterDataSource.h

@@ -0,0 +1,16 @@
+//
+//  ASListKitTestAdapterDataSource.h
+//  AsyncDisplayKit
+//
+//  Created by Adlai Holler on 12/25/16.
+//  Copyright © 2016 Facebook. All rights reserved.
+//
+
+#import <IGListKit/IGListKit.h>
+
+@interface ASListKitTestAdapterDataSource : NSObject <IGListAdapterDataSource>
+
+// array of numbers which is then passed to -[IGListTestSection setItems:]
+@property (nonatomic, strong) NSArray <NSNumber *> *objects;
+
+@end

ASDKListKit/ASDKListKitTests/ASListKitTestAdapterDataSource.m

@@ -0,0 +1,30 @@
+//
+//  ASListKitTestAdapterDataSource.m
+//  AsyncDisplayKit
+//
+//  Created by Adlai Holler on 12/25/16.
+//  Copyright © 2016 Facebook. All rights reserved.
+//
+
+#import "ASListKitTestAdapterDataSource.h"
+#import "ASListTestSection.h"
+
+@implementation ASListKitTestAdapterDataSource
+
+- (NSArray *)objectsForListAdapter:(IGListAdapter *)listAdapter
+{
+  return self.objects;
+}
+
+- (IGListSectionController <IGListSectionType> *)listAdapter:(IGListAdapter *)listAdapter sectionControllerForObject:(id)object
+{
+  ASListTestSection *section = [[ASListTestSection alloc] init];
+  return section;
+}
+
+- (nullable UIView *)emptyViewForListAdapter:(IGListAdapter *)listAdapter
+{
+  return nil;
+}
+
+@end

ASDKListKit/ASDKListKitTests/ASListKitTests.m

@@ -0,0 +1,110 @@
+//
+//  ASListKitTests.m
+//  AsyncDisplayKit
+//
+//  Created by Adlai Holler on 12/25/16.
+//  Copyright © 2016 Facebook. All rights reserved.
+//
+
+#import <XCTest/XCTest.h>
+#import <AsyncDisplayKit/AsyncDisplayKit.h>
+#import "ASListKitTestAdapterDataSource.h"
+#import "ASXCTExtensions.h"
+#import <JGMethodSwizzler/JGMethodSwizzler.h>
+
+@interface ASListKitTests : XCTestCase
+
+@property (nonatomic, strong) ASCollectionNode *collectionNode;
+@property (nonatomic, strong) UICollectionView *collectionView;
+@property (nonatomic, strong) IGListAdapter *adapter;
+@property (nonatomic, strong) ASListKitTestAdapterDataSource *dataSource;
+@property (nonatomic, strong) UICollectionViewFlowLayout *layout;
+@property (nonatomic, strong) UIWindow *window;
+@property (nonatomic) NSInteger reloadDataCount;
+
+@end
+
+@implementation ASListKitTests
+
+- (void)setUp
+{
+  [super setUp];
+
+  [ASCollectionView swizzleInstanceMethod:@selector(reloadData) withReplacement:JGMethodReplacementProviderBlock {
+    return JGMethodReplacement(void, ASCollectionView *) {
+      JGOriginalImplementation(void);
+      _reloadDataCount++;
+    };
+  }];
+
+  self.window = [[UIWindow alloc] initWithFrame:CGRectMake(0, 0, 100, 100)];
+
+  self.layout = [[UICollectionViewFlowLayout alloc] init];
+  self.collectionNode = [[ASCollectionNode alloc] initWithCollectionViewLayout:self.layout];
+  self.collectionNode.frame = self.window.bounds;
+  self.collectionView = self.collectionNode.view;
+
+  [self.window addSubnode:self.collectionNode];
+
+  IGListAdapterUpdater *updater = [[IGListAdapterUpdater alloc] init];
+
+  self.dataSource = [[ASListKitTestAdapterDataSource alloc] init];
+  self.adapter = [[IGListAdapter alloc] initWithUpdater:updater
+                                         viewController:nil
+                                       workingRangeSize:0];
+  self.adapter.dataSource = self.dataSource;
+  [self.adapter setASDKCollectionNode:self.collectionNode];
+  XCTAssertNotNil(self.adapter.collectionView, @"Adapter was not bound to collection view. You may have a stale copy of AsyncDisplayKit that was built without IG_LIST_KIT. Clean Builder Folder IMO.");
+}
+
+- (void)tearDown
+{
+  [super tearDown];
+  XCTAssert([ASCollectionView deswizzleAllMethods]);
+  self.reloadDataCount = 0;
+  self.window = nil;
+  self.collectionNode = nil;
+  self.collectionView = nil;
+  self.adapter = nil;
+  self.dataSource = nil;
+  self.layout = nil;
+}
+
+- (void)test_whenAdapterUpdated_withObjectsOverflow_thatVisibleObjectsIsSubsetOfAllObjects
+{
+  // each section controller returns n items sized 100x10
+  self.dataSource.objects = @[@1, @2, @3, @4, @5, @6];
+  XCTestExpectation *e = [self expectationWithDescription:@"Data update completed"];
+
+  [self.adapter performUpdatesAnimated:NO completion:^(BOOL finished) {
+    [e fulfill];
+  }];
+  
+  [self waitForExpectationsWithTimeout:1 handler:nil];
+  self.collectionNode.view.contentOffset = CGPointMake(0, 30);
+  [self.collectionNode.view layoutIfNeeded];
+
+
+  NSArray *visibleObjects = [[self.adapter visibleObjects] sortedArrayUsingSelector:@selector(compare:)];
+  NSArray *expectedObjects = @[@3, @4, @5];
+  XCTAssertEqualObjects(visibleObjects, expectedObjects);
+}
+
+- (void)test_whenCollectionViewIsNotInAWindow_updaterDoesNotJustCallReloadData
+{
+  [self.collectionView removeFromSuperview];
+
+  [self.collectionView layoutIfNeeded];
+  self.dataSource.objects = @[@1, @2, @3, @4, @5, @6];
+  XCTestExpectation *e = [self expectationWithDescription:@"Data update completed"];
+
+  [self.adapter performUpdatesAnimated:NO completion:^(BOOL finished) {
+    [e fulfill];
+  }];
+  [self waitForExpectationsWithTimeout:1 handler:nil];
+  [self.collectionView layoutIfNeeded];
+
+  XCTAssertEqual(self.reloadDataCount, 2);
+}
+
+@end

ASDKListKit/ASDKListKitTests/ASListTestCellNode.h

@@ -0,0 +1,13 @@
+//
+//  ASListTestCellNode.h
+//  AsyncDisplayKit
+//
+//  Created by Adlai Holler on 12/25/16.
+//  Copyright © 2016 Facebook. All rights reserved.
+//
+
+#import <AsyncDisplayKit/AsyncDisplayKit.h>
+
+@interface ASListTestCellNode : ASCellNode
+
+@end

ASDKListKit/ASDKListKitTests/ASListTestCellNode.m

@@ -0,0 +1,13 @@
+//
+//  ASListTestCellNode.m
+//  AsyncDisplayKit
+//
+//  Created by Adlai Holler on 12/25/16.
+//  Copyright © 2016 Facebook. All rights reserved.
+//
+
+#import "ASListTestCellNode.h"
+
+@implementation ASListTestCellNode
+
+@end

ASDKListKit/ASDKListKitTests/ASListTestObject.h

@@ -0,0 +1,22 @@
+//
+//  ASListTestObject.h
+//  AsyncDisplayKit
+//
+//  Created by Adlai Holler on 12/25/16.
+//  Copyright © 2016 Facebook. All rights reserved.
+//
+
+#import <IGListKit/IGListKit.h>
+
+NS_ASSUME_NONNULL_BEGIN
+
+@interface ASListTestObject : NSObject <IGListDiffable, NSCopying>
+
+- (instancetype)initWithKey:(id <NSCopying>)key value:(id)value;
+
+@property (nonatomic, strong, readonly) id key;
+@property (nonatomic, strong) id value;
+
+@end
+
+NS_ASSUME_NONNULL_END

ASDKListKit/ASDKListKitTests/ASListTestObject.m

@@ -0,0 +1,49 @@
+//
+//  ASListTestObject.m
+//  AsyncDisplayKit
+//
+//  Created by Adlai Holler on 12/25/16.
+//  Copyright © 2016 Facebook. All rights reserved.
+//
+
+#import "ASListTestObject.h"
+
+@implementation ASListTestObject
+
+- (instancetype)initWithKey:(id)key value:(id)value
+{
+  if (self = [super init]) {
+    _key = [key copy];
+    _value = value;
+  }
+  return self;
+}
+
+- (instancetype)copyWithZone:(NSZone *)zone
+{
+  return [[ASListTestObject alloc] initWithKey:self.key value:self.value];
+}
+
+#pragma mark - IGListDiffable
+
+- (id<NSObject>)diffIdentifier
+{
+  return self.key;
+}
+
+- (BOOL)isEqualToDiffableObject:(id)object
+{
+  if (object == self) {
+    return YES;
+  }
+  if ([object isKindOfClass:[ASListTestObject class]]) {
+    id k1 = self.key;
+    id k2 = [object key];
+    id v1 = self.value;
+    id v2 = [(ASListTestObject *)object value];
+    return (v1 == v2 || [v1 isEqual:v2]) && (k1 == k2 || [k1 isEqual:k2]);
+  }
+  return NO;
+}
+
+@end

ASDKListKit/ASDKListKitTests/ASListTestSection.h

@@ -0,0 +1,18 @@
+//
+//  ASListTestSection.h
+//  AsyncDisplayKit
+//
+//  Created by Adlai Holler on 12/25/16.
+//  Copyright © 2016 Facebook. All rights reserved.
+//
+
+#import <IGListKit/IGListKit.h>
+#import <AsyncDisplayKit/AsyncDisplayKit.h>
+
+@interface ASListTestSection : IGListSectionController <IGListSectionType, ASSectionController>
+
+@property (nonatomic) NSInteger itemCount;
+
+@property (nonatomic) NSInteger selectedItemIndex;
+
+@end

ASDKListKit/ASDKListKitTests/ASListTestSection.m

@@ -0,0 +1,58 @@
+//
+//  ASListTestSection.m
+//  AsyncDisplayKit
+//
+//  Created by Adlai Holler on 12/25/16.
+//  Copyright © 2016 Facebook. All rights reserved.
+//
+
+#import "ASListTestSection.h"
+#import "ASListTestCellNode.h"
+
+@implementation ASListTestSection
+
+- (instancetype)init
+{
+  if (self = [super init])
+{
+    _selectedItemIndex = NSNotFound;
+  }
+  return self;
+}
+
+- (NSInteger)numberOfItems
+{
+  return self.itemCount;
+}
+
+- (CGSize)sizeForItemAtIndex:(NSInteger)index
+{
+  ASDisplayNodeFailAssert(@"Did not expect %@ to be called.", NSStringFromSelector(_cmd));
+  return CGSizeMake(100, 10);
+}
+
+ASIGSectionControllerCellForIndexImplementation
+
+- (void)didUpdateToObject:(id)object
+{
+  if ([object isKindOfClass:[NSNumber class]])
+{
+    self.itemCount = [object integerValue];
+  }
+}
+
+- (void)didSelectItemAtIndex:(NSInteger)index
+{
+  self.selectedItemIndex = index;
+}
+
+- (ASCellNodeBlock)nodeBlockForItemAtIndex:(NSInteger)index
+{
+  return ^{
+    ASListTestCellNode *node = [[ASListTestCellNode alloc] init];
+    node.style.preferredSize = CGSizeMake(100, 10);
+    return node;
+  };
+}
+
+@end

ASDKListKit/ASDKListKitTests/ASListTestSupplementaryNode.h

@@ -0,0 +1,13 @@
+//
+//  ASListTestSupplementaryNode.h
+//  AsyncDisplayKit
+//
+//  Created by Adlai Holler on 12/25/16.
+//  Copyright © 2016 Facebook. All rights reserved.
+//
+
+#import <AsyncDisplayKit/AsyncDisplayKit.h>
+
+@interface ASListTestSupplementaryNode : ASCellNode
+
+@end

ASDKListKit/ASDKListKitTests/ASListTestSupplementaryNode.m

@@ -0,0 +1,13 @@
+//
+//  ASListTestSupplementaryNode.m
+//  AsyncDisplayKit
+//
+//  Created by Adlai Holler on 12/25/16.
+//  Copyright © 2016 Facebook. All rights reserved.
+//
+
+#import "ASListTestSupplementaryNode.h"
+
+@implementation ASListTestSupplementaryNode
+
+@end

ASDKListKit/ASDKListKitTests/ASListTestSupplementarySource.h

@@ -0,0 +1,20 @@
+//
+//  ASListTestSupplementarySource.h
+//  AsyncDisplayKit
+//
+//  Created by Adlai Holler on 12/25/16.
+//  Copyright © 2016 Facebook. All rights reserved.
+//
+
+#import <IGListKit/IGListKit.h>
+#import <AsyncDisplayKit/AsyncDisplayKit.h>
+
+@interface ASListTestSupplementarySource : NSObject <IGListSupplementaryViewSource, ASSupplementaryNodeSource>
+
+@property (nonatomic, strong, readwrite) NSArray<NSString *> *supportedElementKinds;
+
+@property (nonatomic, weak) id<IGListCollectionContext> collectionContext;
+
+@property (nonatomic, weak) IGListSectionController<IGListSectionType> *sectionController;
+
+@end

ASDKListKit/ASDKListKitTests/ASListTestSupplementarySource.m

@@ -0,0 +1,24 @@
+//
+//  ASListTestSupplementarySource.m
+//  AsyncDisplayKit
+//
+//  Created by Adlai Holler on 12/25/16.
+//  Copyright © 2016 Facebook. All rights reserved.
+//
+
+#import "ASListTestSupplementarySource.h"
+#import "ASListTestSupplementaryNode.h"
+
+@implementation ASListTestSupplementarySource
+
+ASIGSupplementarySourceViewForSupplementaryElementImplementation(self.sectionController)
+ASIGSupplementarySourceSizeForSupplementaryElementImplementation
+
+- (ASCellNode *)nodeForSupplementaryElementOfKind:(NSString *)elementKind atIndex:(NSInteger)index
+{
+  ASListTestSupplementaryNode *node = [[ASListTestSupplementaryNode alloc] init];
+  node.style.preferredSize = CGSizeMake(100, 10);
+  return node;
+}
+
+@end

ASDKListKit/ASDKListKitTests/ASXCTExtensions.h

@@ -0,0 +1,36 @@
+/**
+ * XCTest extensions for CGGeometry.
+ *
+ * Prefer these to XCTAssert(CGRectEqualToRect(...)) because you get output
+ * that tells you what went wrong.
+ * Could use NSValue, but using strings makes the description messages shorter.
+ */
+
+#import <XCTest/XCTestAssertionsImpl.h>
+
+#define ASXCTAssertEqualSizes(s0, s1, ...) \
+  _XCTPrimitiveAssertEqualObjects(self, NSStringFromCGSize(s0), @#s0, NSStringFromCGSize(s1), @#s1, __VA_ARGS__)
+
+#define ASXCTAssertNotEqualSizes(s0, s1, ...) \
+  _XCTPrimitiveAssertNotEqualObjects(self, NSStringFromCGSize(s0), @#s0, NSStringFromCGSize(s1), @#s1, __VA_ARGS__)
+
+#define ASXCTAssertEqualPoints(p0, p1, ...) \
+  _XCTPrimitiveAssertEqualObjects(self, NSStringFromCGPoint(p0), @#p0, NSStringFromCGPoint(p1), @#p1, __VA_ARGS__)
+
+#define ASXCTAssertNotEqualPoints(p0, p1, ...) \
+  _XCTPrimitiveAssertNotEqualObjects(self, NSStringFromCGPoint(p0), @#p0, NSStringFromCGPoint(p1), @#p1, __VA_ARGS__)
+
+#define ASXCTAssertEqualRects(r0, r1, ...) \
+  _XCTPrimitiveAssertEqualObjects(self, NSStringFromCGRect(r0), @#r0, NSStringFromCGRect(r1), @#r1, __VA_ARGS__)
+
+#define ASXCTAssertNotEqualRects(r0, r1, ...) \
+  _XCTPrimitiveAssertNotEqualObjects(self, NSStringFromCGRect(r0), @#r0, NSStringFromCGRect(r1), @#r1, __VA_ARGS__)
+
+#define ASXCTAssertEqualDimensions(r0, r1, ...) \
+  _XCTPrimitiveAssertEqualObjects(self, NSStringFromASDimension(r0), @#r0, NSStringFromASDimension(r1), @#r1, __VA_ARGS__)
+
+#define ASXCTAssertNotEqualDimensions(r0, r1, ...) \
+  _XCTPrimitiveAssertNotEqualObjects(self, NSStringFromASDimension(r0), @#r0, NSStringFromASDimension(r1), @#r1, __VA_ARGS__)
+
+#define ASXCTAssertEqualSizeRanges(r0, r1, ...) \
+  _XCTPrimitiveAssertEqualObjects(self, NSStringFromASSizeRange(r0), @#r0, NSStringFromASSizeRange(r1), @#r1, __VA_ARGS__)

ASDKListKit/ASDKListKitTests/Info.plist

@@ -0,0 +1,22 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
+<plist version="1.0">
+<dict>
+	<key>CFBundleDevelopmentRegion</key>
+	<string>en</string>
+	<key>CFBundleExecutable</key>
+	<string>$(EXECUTABLE_NAME)</string>
+	<key>CFBundleIdentifier</key>
+	<string>$(PRODUCT_BUNDLE_IDENTIFIER)</string>
+	<key>CFBundleInfoDictionaryVersion</key>
+	<string>6.0</string>
+	<key>CFBundleName</key>
+	<string>$(PRODUCT_NAME)</string>
+	<key>CFBundlePackageType</key>
+	<string>BNDL</string>
+	<key>CFBundleShortVersionString</key>
+	<string>1.0</string>
+	<key>CFBundleVersion</key>
+	<string>1</string>
+</dict>
+</plist>

ASDKListKit/Podfile

@@ -0,0 +1,8 @@
+source 'https://github.com/CocoaPods/Specs.git'
+
+platform :ios, '8.0'
+target 'ASDKListKitTests' do
+	pod 'AsyncDisplayKit/IGListKit', :path => '..'
+	pod 'JGMethodSwizzler', :git => 'https://github.com/JonasGessner/JGMethodSwizzler', :branch => 'master'
+end
+

AsyncDisplayKit.podspec

@@ -47,6 +47,12 @@ Pod::Spec.new do |spec|
       pin.dependency 'PINRemoteImage/PINCache'
       pin.dependency 'AsyncDisplayKit/Core'
   end
+
+  spec.subspec 'IGListKit' do |igl|
+      igl.xcconfig = { 'GCC_PREPROCESSOR_DEFINITIONS' => '$(inherited) IG_LIST_KIT=1' }
+      igl.dependency 'IGListKit', '2.1.0'
+      igl.dependency 'AsyncDisplayKit/Core'
+  end
   
   # Include optional PINRemoteImage module
   spec.default_subspec = 'PINRemoteImage'

AsyncDisplayKit.xcodeproj/project.pbxproj

@@ -459,15 +459,30 @@
 		CC4C2A7A1D8902350039ACAB /* ASTraceEvent.h in CopyFiles */ = {isa = PBXBuildFile; fileRef = CC4C2A751D88E3BF0039ACAB /* ASTraceEvent.h */; };
 		CC54A81C1D70079800296A24 /* ASDispatch.h in Headers */ = {isa = PBXBuildFile; fileRef = CC54A81B1D70077A00296A24 /* ASDispatch.h */; };
 		CC54A81E1D7008B300296A24 /* ASDispatchTests.m in Sources */ = {isa = PBXBuildFile; fileRef = CC54A81D1D7008B300296A24 /* ASDispatchTests.m */; };
+		CC6363E21E32C00800D8A8DE /* ASCollectionInteropProtocols.h in Headers */ = {isa = PBXBuildFile; fileRef = CC6363E11E32C00800D8A8DE /* ASCollectionInteropProtocols.h */; };
+		CC6363E31E32C01900D8A8DE /* ASCollectionInteropProtocols.h in CopyFiles */ = {isa = PBXBuildFile; fileRef = CC6363E11E32C00800D8A8DE /* ASCollectionInteropProtocols.h */; };
 		CC7FD9DF1BB5E962005CCB2B /* ASPhotosFrameworkImageRequest.m in Sources */ = {isa = PBXBuildFile; fileRef = CC7FD9DD1BB5E962005CCB2B /* ASPhotosFrameworkImageRequest.m */; };
 		CC7FD9E11BB5F750005CCB2B /* ASPhotosFrameworkImageRequestTests.m in Sources */ = {isa = PBXBuildFile; fileRef = CC7FD9E01BB5F750005CCB2B /* ASPhotosFrameworkImageRequestTests.m */; };
 		CC7FD9E21BB603FF005CCB2B /* ASPhotosFrameworkImageRequest.h in Headers */ = {isa = PBXBuildFile; fileRef = CC7FD9DC1BB5E962005CCB2B /* ASPhotosFrameworkImageRequest.h */; settings = {ATTRIBUTES = (Public, ); }; };
+		CC8525151E3FC253008EABE6 /* _ASCollectionViewCell.h in Headers */ = {isa = PBXBuildFile; fileRef = CC8525131E3FC253008EABE6 /* _ASCollectionViewCell.h */; settings = {ATTRIBUTES = (Private, ); }; };
+		CC8525161E3FC253008EABE6 /* _ASCollectionViewCell.m in Sources */ = {isa = PBXBuildFile; fileRef = CC8525141E3FC253008EABE6 /* _ASCollectionViewCell.m */; };
+		CC8525171E3FC253008EABE6 /* _ASCollectionViewCell.m in Sources */ = {isa = PBXBuildFile; fileRef = CC8525141E3FC253008EABE6 /* _ASCollectionViewCell.m */; };
+		CC8525181E3FC316008EABE6 /* _ASCollectionViewCell.h in CopyFiles */ = {isa = PBXBuildFile; fileRef = CC8525131E3FC253008EABE6 /* _ASCollectionViewCell.h */; };
 		CC87BB951DA8193C0090E380 /* ASCellNode+Internal.h in Headers */ = {isa = PBXBuildFile; fileRef = CC87BB941DA8193C0090E380 /* ASCellNode+Internal.h */; };
 		CC8B05D61D73836400F54286 /* ASPerformanceTestContext.m in Sources */ = {isa = PBXBuildFile; fileRef = CC8B05D51D73836400F54286 /* ASPerformanceTestContext.m */; };
 		CC8B05D81D73979700F54286 /* ASTextNodePerformanceTests.m in Sources */ = {isa = PBXBuildFile; fileRef = CC8B05D71D73979700F54286 /* ASTextNodePerformanceTests.m */; };
 		CCA221D31D6FA7EF00AF6A0F /* ASViewControllerTests.m in Sources */ = {isa = PBXBuildFile; fileRef = CCA221D21D6FA7EF00AF6A0F /* ASViewControllerTests.m */; };
 		CCB2F34D1D63CCC6004E6DE9 /* ASDisplayNodeSnapshotTests.m in Sources */ = {isa = PBXBuildFile; fileRef = CCB2F34C1D63CCC6004E6DE9 /* ASDisplayNodeSnapshotTests.m */; };
+		CCE04B1F1E313EA7006AEBBB /* ASSectionController.h in Headers */ = {isa = PBXBuildFile; fileRef = CCE04B1E1E313EA7006AEBBB /* ASSectionController.h */; settings = {ATTRIBUTES = (Public, ); }; };
+		CCE04B221E313EB9006AEBBB /* IGListAdapter+AsyncDisplayKit.h in Headers */ = {isa = PBXBuildFile; fileRef = CCE04B201E313EB9006AEBBB /* IGListAdapter+AsyncDisplayKit.h */; };
+		CCE04B231E313EB9006AEBBB /* IGListAdapter+AsyncDisplayKit.m in Sources */ = {isa = PBXBuildFile; fileRef = CCE04B211E313EB9006AEBBB /* IGListAdapter+AsyncDisplayKit.m */; };
+		CCE04B241E313EB9006AEBBB /* IGListAdapter+AsyncDisplayKit.m in Sources */ = {isa = PBXBuildFile; fileRef = CCE04B211E313EB9006AEBBB /* IGListAdapter+AsyncDisplayKit.m */; };
+		CCE04B2C1E314A32006AEBBB /* ASSupplementaryNodeSource.h in Headers */ = {isa = PBXBuildFile; fileRef = CCE04B2B1E314A32006AEBBB /* ASSupplementaryNodeSource.h */; settings = {ATTRIBUTES = (Public, ); }; };
+		CCE04B2E1E314A9C006AEBBB /* ASSectionController.h in CopyFiles */ = {isa = PBXBuildFile; fileRef = CCE04B1E1E313EA7006AEBBB /* ASSectionController.h */; };
+		CCE04B2F1E314A9C006AEBBB /* ASSupplementaryNodeSource.h in CopyFiles */ = {isa = PBXBuildFile; fileRef = CCE04B2B1E314A32006AEBBB /* ASSupplementaryNodeSource.h */; };
+		CCE04B301E314A9C006AEBBB /* IGListAdapter+AsyncDisplayKit.h in CopyFiles */ = {isa = PBXBuildFile; fileRef = CCE04B201E313EB9006AEBBB /* IGListAdapter+AsyncDisplayKit.h */; };
 		CCF18FF41D2575E300DF5895 /* NSIndexSet+ASHelpers.h in Headers */ = {isa = PBXBuildFile; fileRef = CC4981BA1D1C7F65004E13CC /* NSIndexSet+ASHelpers.h */; };
+		CCF92DCD1E3155180019E9C6 /* ASIGListKitMethodImplementations.h in Headers */ = {isa = PBXBuildFile; fileRef = CCF92DCC1E3155180019E9C6 /* ASIGListKitMethodImplementations.h */; };
 		D785F6631A74327E00291744 /* ASScrollNode.mm in Sources */ = {isa = PBXBuildFile; fileRef = D785F6611A74327E00291744 /* ASScrollNode.mm */; };
 		DB55C2631C6408D6004EDCF5 /* _ASTransitionContext.m in Sources */ = {isa = PBXBuildFile; fileRef = DB55C2601C6408D6004EDCF5 /* _ASTransitionContext.m */; };
 		DB55C2671C641AE4004EDCF5 /* ASContextTransitioning.h in Headers */ = {isa = PBXBuildFile; fileRef = DB55C2651C641AE4004EDCF5 /* ASContextTransitioning.h */; settings = {ATTRIBUTES = (Public, ); }; };
@@ -674,6 +689,7 @@
 			dstPath = "include/$(PRODUCT_NAME)";
 			dstSubfolderSpec = 16;
 			files = (
+				CC8525181E3FC316008EABE6 /* _ASCollectionViewCell.h in CopyFiles */,
 				690ED59D1E36D140000627C0 /* ASImageNode+tvOS.h in CopyFiles */,
 				690ED59C1E36D13A000627C0 /* ASControlNode+tvOS.h in CopyFiles */,
 				690ED58F1E36BCBF000627C0 /* ASLayoutElementStylePrivate.h in CopyFiles */,
@@ -682,6 +698,10 @@
 				692BE8D81E36B66500C86D87 /* ASLayoutSpecPrivate.h in CopyFiles */,
 				6947B0C71E36B5B60007C478 /* ASStackPositionedLayout.h in CopyFiles */,
 				6947B0C61E36B5A90007C478 /* ASStackUnpositionedLayout.h in CopyFiles */,
+				CC6363E31E32C01900D8A8DE /* ASCollectionInteropProtocols.h in CopyFiles */,
+				CCE04B2E1E314A9C006AEBBB /* ASSectionController.h in CopyFiles */,
+				CCE04B2F1E314A9C006AEBBB /* ASSupplementaryNodeSource.h in CopyFiles */,
+				CCE04B301E314A9C006AEBBB /* IGListAdapter+AsyncDisplayKit.h in CopyFiles */,
 				693DA5141E25373100F66DF4 /* ASDimensionDeprecated.h in CopyFiles */,
 				693DA50F1E2536A600F66DF4 /* ASDimensionInternal.h in CopyFiles */,
 				68C2155C1DE11AA80019C4BC /* ASObjectDescriptionHelpers.h in CopyFiles */,
@@ -967,7 +987,7 @@
 		257754BC1BEE458E00737CA5 /* ASTextNodeTypes.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; name = ASTextNodeTypes.h; path = TextKit/ASTextNodeTypes.h; sourceTree = "<group>"; };
 		257754BD1BEE458E00737CA5 /* ASTextNodeWordKerner.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; name = ASTextNodeWordKerner.m; path = TextKit/ASTextNodeWordKerner.m; sourceTree = "<group>"; };
 		25E327541C16819500A2170C /* ASPagerNode.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; lineEnding = 0; path = ASPagerNode.h; sourceTree = "<group>"; };
-		25E327551C16819500A2170C /* ASPagerNode.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; lineEnding = 0; path = ASPagerNode.m; sourceTree = "<group>"; xcLanguageSpecificationIdentifier = xcode.lang.objc; };
+		25E327551C16819500A2170C /* ASPagerNode.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; lineEnding = 0; path = ASPagerNode.m; sourceTree = "<group>"; };
 		2911485B1A77147A005D0878 /* ASControlNodeTests.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = ASControlNodeTests.m; sourceTree = "<group>"; };
 		292C59991A956527007E5DD6 /* ASLayoutRangeType.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = ASLayoutRangeType.h; sourceTree = "<group>"; };
 		2967F9E11AB0A4CF0072E4AB /* ASBasicImageDownloaderInternal.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = ASBasicImageDownloaderInternal.h; sourceTree = "<group>"; };
@@ -1158,15 +1178,23 @@
 		CC512B841DAC45C60054848E /* ASTableView+Undeprecated.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = "ASTableView+Undeprecated.h"; sourceTree = "<group>"; };
 		CC54A81B1D70077A00296A24 /* ASDispatch.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = ASDispatch.h; sourceTree = "<group>"; };
 		CC54A81D1D7008B300296A24 /* ASDispatchTests.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = ASDispatchTests.m; sourceTree = "<group>"; };
+		CC6363E11E32C00800D8A8DE /* ASCollectionInteropProtocols.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = ASCollectionInteropProtocols.h; sourceTree = "<group>"; };
 		CC7FD9DC1BB5E962005CCB2B /* ASPhotosFrameworkImageRequest.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = ASPhotosFrameworkImageRequest.h; sourceTree = "<group>"; };
 		CC7FD9DD1BB5E962005CCB2B /* ASPhotosFrameworkImageRequest.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = ASPhotosFrameworkImageRequest.m; sourceTree = "<group>"; };
 		CC7FD9E01BB5F750005CCB2B /* ASPhotosFrameworkImageRequestTests.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = ASPhotosFrameworkImageRequestTests.m; sourceTree = "<group>"; };
+		CC8525131E3FC253008EABE6 /* _ASCollectionViewCell.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = _ASCollectionViewCell.h; sourceTree = "<group>"; };
+		CC8525141E3FC253008EABE6 /* _ASCollectionViewCell.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = _ASCollectionViewCell.m; sourceTree = "<group>"; };
 		CC87BB941DA8193C0090E380 /* ASCellNode+Internal.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; name = "ASCellNode+Internal.h"; path = "AsyncDisplayKit/ASCellNode+Internal.h"; sourceTree = SOURCE_ROOT; };
 		CC8B05D41D73836400F54286 /* ASPerformanceTestContext.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = ASPerformanceTestContext.h; sourceTree = "<group>"; };
 		CC8B05D51D73836400F54286 /* ASPerformanceTestContext.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = ASPerformanceTestContext.m; sourceTree = "<group>"; };
 		CC8B05D71D73979700F54286 /* ASTextNodePerformanceTests.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = ASTextNodePerformanceTests.m; sourceTree = "<group>"; };
 		CCA221D21D6FA7EF00AF6A0F /* ASViewControllerTests.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = ASViewControllerTests.m; sourceTree = "<group>"; };
 		CCB2F34C1D63CCC6004E6DE9 /* ASDisplayNodeSnapshotTests.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = ASDisplayNodeSnapshotTests.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>"; };
+		CCE04B2B1E314A32006AEBBB /* ASSupplementaryNodeSource.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = ASSupplementaryNodeSource.h; sourceTree = "<group>"; };
+		CCF92DCC1E3155180019E9C6 /* ASIGListKitMethodImplementations.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = ASIGListKitMethodImplementations.h; sourceTree = "<group>"; };
 		D3779BCFF841AD3EB56537ED /* Pods-AsyncDisplayKitTests.release.xcconfig */ = {isa = PBXFileReference; includeInIndex = 1; lastKnownFileType = text.xcconfig; name = "Pods-AsyncDisplayKitTests.release.xcconfig"; path = "Pods/Target Support Files/Pods-AsyncDisplayKitTests/Pods-AsyncDisplayKitTests.release.xcconfig"; sourceTree = "<group>"; };
 		D785F6601A74327E00291744 /* ASScrollNode.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = ASScrollNode.h; sourceTree = "<group>"; };
 		D785F6611A74327E00291744 /* ASScrollNode.mm */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.objcpp; path = ASScrollNode.mm; sourceTree = "<group>"; };
@@ -1316,6 +1344,7 @@
 		058D09B1195D04C000B7D73C /* AsyncDisplayKit */ = {
 			isa = PBXGroup;
 			children = (
+				CCE04B1D1E313E99006AEBBB /* Collection Data Adapter */,
 				DBDB83921C6E879900D0098C /* ASPagerFlowLayout.h */,
 				DBDB83931C6E879900D0098C /* ASPagerFlowLayout.m */,
 				92DD2FE11BF4B97E0074C9DD /* ASMapNode.h */,
@@ -1485,6 +1514,8 @@
 		058D09E1195D050800B7D73C /* Details */ = {
 			isa = PBXGroup;
 			children = (
+				CC8525131E3FC253008EABE6 /* _ASCollectionViewCell.h */,
+				CC8525141E3FC253008EABE6 /* _ASCollectionViewCell.m */,
 				058D09E2195D050800B7D73C /* _ASDisplayLayer.h */,
 				058D09E3195D050800B7D73C /* _ASDisplayLayer.mm */,
 				058D09E4195D050800B7D73C /* _ASDisplayView.h */,
@@ -1577,6 +1608,7 @@
 			isa = PBXGroup;
 			children = (
 				6947B0BB1E36B4E30007C478 /* Layout */,
+				CCE04B2A1E313EDA006AEBBB /* Collection Data Adapter */,
 				058D0A03195D050800B7D73C /* _ASCoreAnimationExtras.h */,
 				058D0A04195D050800B7D73C /* _ASCoreAnimationExtras.mm */,
 				AC026B6D1BD57DBF00BBC17E /* _ASHierarchyChangeSet.h */,
@@ -1784,6 +1816,34 @@
 			name = "Supporting Files";
 			sourceTree = "<group>";
 		};
+		CCE04B1D1E313E99006AEBBB /* Collection Data Adapter */ = {
+			isa = PBXGroup;
+			children = (
+				CCE04B1E1E313EA7006AEBBB /* ASSectionController.h */,
+				CCE04B2B1E314A32006AEBBB /* ASSupplementaryNodeSource.h */,
+				CCF92DCE1E315FC50019E9C6 /* IGListKit Support */,
+			);
+			name = "Collection Data Adapter";
+			sourceTree = "<group>";
+		};
+		CCE04B2A1E313EDA006AEBBB /* Collection Data Adapter */ = {
+			isa = PBXGroup;
+			children = (
+				CC6363E11E32C00800D8A8DE /* ASCollectionInteropProtocols.h */,
+			);
+			name = "Collection Data Adapter";
+			sourceTree = "<group>";
+		};
+		CCF92DCE1E315FC50019E9C6 /* IGListKit Support */ = {
+			isa = PBXGroup;
+			children = (
+				CCF92DCC1E3155180019E9C6 /* ASIGListKitMethodImplementations.h */,
+				CCE04B201E313EB9006AEBBB /* IGListAdapter+AsyncDisplayKit.h */,
+				CCE04B211E313EB9006AEBBB /* IGListAdapter+AsyncDisplayKit.m */,
+			);
+			name = "IGListKit Support";
+			sourceTree = "<group>";
+		};
 		DE89C1691DCEB9CC00D49D74 /* Debug */ = {
 			isa = PBXGroup;
 			children = (
@@ -1855,11 +1915,13 @@
 				254C6B731BF94DF4003EC431 /* ASTextKitCoreTextAdditions.h in Headers */,
 				A2763D7A1CBDD57D00A9ADBD /* ASPINRemoteImageDownloader.h in Headers */,
 				254C6B7A1BF94DF4003EC431 /* ASTextKitRenderer.h in Headers */,
+				CCE04B1F1E313EA7006AEBBB /* ASSectionController.h in Headers */,
 				69CB62AC1CB8165900024920 /* _ASDisplayViewAccessiblity.h in Headers */,
 				68355B3F1CB57A64001D4E68 /* ASPINRemoteImageDownloader.h in Headers */,
 				254C6B7C1BF94DF4003EC431 /* ASTextKitRenderer+TextChecking.h in Headers */,
 				34EFC7611B701C9C00AD841F /* ASBackgroundLayoutSpec.h in Headers */,
 				68AF37DB1CBEF4D80077BF76 /* ASImageNode+AnimatedImagePrivate.h in Headers */,
+				CCE04B221E313EB9006AEBBB /* IGListAdapter+AsyncDisplayKit.h in Headers */,
 				B35062591B010F070018CF92 /* ASBaseDefines.h in Headers */,
 				B35062131B010EFD0018CF92 /* ASBasicImageDownloader.h in Headers */,
 				B35062461B010EFD0018CF92 /* ASBasicImageDownloaderInternal.h in Headers */,
@@ -1883,6 +1945,7 @@
 				9C70F20F1CDBE9FF007D6C76 /* ASLayoutManager.h in Headers */,
 				B35061FA1B010EFD0018CF92 /* ASControlNode+Subclasses.h in Headers */,
 				6947B0C31E36B5040007C478 /* ASStackPositionedLayout.h in Headers */,
+				CC6363E21E32C00800D8A8DE /* ASCollectionInteropProtocols.h in Headers */,
 				B35061F81B010EFD0018CF92 /* ASControlNode.h in Headers */,
 				B35062171B010EFD0018CF92 /* ASDataController.h in Headers */,
 				34EFC75B1B701BAF00AD841F /* ASDimension.h in Headers */,
@@ -1901,6 +1964,7 @@
 				B350621B1B010EFD0018CF92 /* ASFlowLayoutController.h in Headers */,
 				B350621D1B010EFD0018CF92 /* ASHighlightOverlayLayer.h in Headers */,
 				C78F7E2B1BF7809800CDEAFC /* ASTableNode.h in Headers */,
+				CCF92DCD1E3155180019E9C6 /* ASIGListKitMethodImplementations.h in Headers */,
 				AC7A2C181BDE11DF0093FE1A /* ASTableViewInternal.h in Headers */,
 				B35062531B010EFD0018CF92 /* ASImageNode+CGExtras.h in Headers */,
 				254C6B7F1BF94DF4003EC431 /* ASTextKitTruncating.h in Headers */,
@@ -1935,6 +1999,7 @@
 				DECBD6E81BE56E1900CF4905 /* ASButtonNode.h in Headers */,
 				B35062241B010EFD0018CF92 /* ASMutableAttributedStringBuilder.h in Headers */,
 				B13CA0F81C519EBA00E031AB /* ASCollectionViewLayoutFacilitatorProtocol.h in Headers */,
+				CCE04B2C1E314A32006AEBBB /* ASSupplementaryNodeSource.h in Headers */,
 				8BBBAB8C1CEBAF1700107FC6 /* ASDefaultPlaybackButton.h in Headers */,
 				B35062061B010EFD0018CF92 /* ASNetworkImageNode.h in Headers */,
 				34EFC76C1B701CED00AD841F /* ASOverlayLayoutSpec.h in Headers */,
@@ -1973,6 +2038,7 @@
 				9C6BB3B31B8CC9C200F13F52 /* ASAbsoluteLayoutElement.h in Headers */,
 				34EFC7731B701D0700AD841F /* ASAbsoluteLayoutSpec.h in Headers */,
 				254C6B781BF94DF4003EC431 /* ASTextKitContext.h in Headers */,
+				CC8525151E3FC253008EABE6 /* _ASCollectionViewCell.h in Headers */,
 				B350620A1B010EFD0018CF92 /* ASTableView.h in Headers */,
 				B350620C1B010EFD0018CF92 /* ASTableViewProtocols.h in Headers */,
 				B350620D1B010EFD0018CF92 /* ASTextNode.h in Headers */,
@@ -2227,6 +2293,7 @@
 				AC6456091B0A335000CF11B8 /* ASCellNode.mm in Sources */,
 				DE8BEAC31C2DF3FC00D57C12 /* ASDelegateProxy.m in Sources */,
 				ACF6ED1D1B17843500DA7C62 /* ASCenterLayoutSpec.mm in Sources */,
+				CC8525161E3FC253008EABE6 /* _ASCollectionViewCell.m in Sources */,
 				9F98C0251DBDF2A300476D92 /* ASControlTargetAction.m in Sources */,
 				18C2ED801B9B7DE800F627B3 /* ASCollectionNode.mm in Sources */,
 				92DD2FE41BF4B97E0074C9DD /* ASMapNode.mm in Sources */,
@@ -2274,6 +2341,7 @@
 				AC6145431D8AFD4F003D62A2 /* ASSection.m in Sources */,
 				058D0A1B195D050800B7D73C /* ASMutableAttributedStringBuilder.m in Sources */,
 				055B9FA91A1C154B00035D6D /* ASNetworkImageNode.mm in Sources */,
+				CCE04B231E313EB9006AEBBB /* IGListAdapter+AsyncDisplayKit.m in Sources */,
 				AEB7B01B1C5962EA00662EF4 /* ASDefaultPlayButton.m in Sources */,
 				CC3B20851C3F76D600798563 /* ASPendingStateController.mm in Sources */,
 				ACF6ED2C1B17843500DA7C62 /* ASOverlayLayoutSpec.mm in Sources */,
@@ -2418,6 +2486,7 @@
 				DE8BEAC41C2DF3FC00D57C12 /* ASDelegateProxy.m in Sources */,
 				9C70F2081CDAA3C6007D6C76 /* ASEnvironment.mm in Sources */,
 				B35062141B010EFD0018CF92 /* ASBasicImageDownloader.mm in Sources */,
+				CC8525171E3FC253008EABE6 /* _ASCollectionViewCell.m in Sources */,
 				B35062161B010EFD0018CF92 /* ASBatchContext.mm in Sources */,
 				AC47D9421B3B891B00AAEE9D /* ASCellNode.mm in Sources */,
 				34EFC7641B701CC600AD841F /* ASCenterLayoutSpec.mm in Sources */,
@@ -2465,6 +2534,7 @@
 				34EFC7681B701CDE00AD841F /* ASLayout.mm in Sources */,
 				DECBD6EA1BE56E1900CF4905 /* ASButtonNode.mm in Sources */,
 				254C6B841BF94F8A003EC431 /* ASTextNodeWordKerner.m in Sources */,
+				CCE04B241E313EB9006AEBBB /* IGListAdapter+AsyncDisplayKit.m in Sources */,
 				34EFC76B1B701CEB00AD841F /* ASLayoutSpec.mm in Sources */,
 				CC3B20861C3F76D600798563 /* ASPendingStateController.mm in Sources */,
 				254C6B8C1BF94F8A003EC431 /* ASTextKitTailTruncater.mm in Sources */,

AsyncDisplayKit/ASCollectionNode.h

@@ -501,6 +501,16 @@ NS_ASSUME_NONNULL_BEGIN
  */
 - (nullable id<ASSectionContext>)collectionNode:(ASCollectionNode *)collectionNode contextForSection:(NSInteger)section;
 
+/**
+ * Asks the data source to provide an array of supplementary element kinds that exist in a given section.
+ *
+ * @param collectionNode The sender.
+ * @param section The index of the section to provide supplementary kinds for.
+ *
+ * @return The supplementary element kinds that exist in the given section, if any.
+ */
+- (NSArray<NSString *> *)collectionNode:(ASCollectionNode *)collectionNode supplementaryElementKindsInSection:(NSInteger)section;
+
 /**
  * Similar to -collectionView:cellForItemAtIndexPath:.
  *

AsyncDisplayKit/ASCollectionNode.mm

@@ -13,6 +13,7 @@
 #import "ASCollectionInternal.h"
 #import "ASCollectionViewLayoutFacilitatorProtocol.h"
 #import "ASCollectionNode.h"
+#import "ASCollectionNode+Beta.h"
 #import "ASDisplayNode+Subclasses.h"
 #import "ASDisplayNode+FrameworkPrivate.h"
 #import "ASEnvironmentInternal.h"

AsyncDisplayKit/ASCollectionView.mm

@@ -8,12 +8,18 @@
 //  of patent rights can be found in the PATENTS file in the same directory.
 //
 
+#import "ASCollectionView.h"
+
+#import <objc/runtime.h>
+
+#import "_ASCollectionViewCell.h"
 #import "ASAssert.h"
 #import "ASAvailability.h"
 #import "ASBatchFetching.h"
 #import "ASDelegateProxy.h"
 #import "ASCellNode+Internal.h"
 #import "ASCollectionDataController.h"
+#import "ASCollectionInternal.h"
 #import "ASCollectionViewLayoutController.h"
 #import "ASCollectionViewFlowLayoutInspector.h"
 #import "ASDisplayNodeExtras.h"
@@ -27,6 +33,7 @@
 #import "ASSectionContext.h"
 #import "ASCollectionView+Undeprecated.h"
 #import "_ASHierarchyChangeSet.h"
+#import "ASCollectionInteropProtocols.h"
 
 /**
  * A macro to get self.collectionNode and assign it to a local variable, or return
@@ -62,79 +69,6 @@ static const NSUInteger kASCollectionViewAnimationNone = UITableViewRowAnimation
 /// Used for all cells and supplementaries. UICV keys by supp-kind+reuseID so this is plenty.
 static NSString * const kReuseIdentifier = @"_ASCollectionReuseIdentifier";
 
-#pragma mark -
-#pragma mark ASCellNode<->UICollectionViewCell bridging.
-
-@class _ASCollectionViewCell;
-
-@interface _ASCollectionViewCell : UICollectionViewCell
-@property (nonatomic, weak) ASCellNode *node;
-@property (nonatomic, strong) UICollectionViewLayoutAttributes *layoutAttributes;
-@end
-
-@implementation _ASCollectionViewCell
-
-- (void)setNode:(ASCellNode *)node
-{
-  ASDisplayNodeAssertMainThread();
-  node.layoutAttributes = _layoutAttributes;
-  _node = node;
-  self.backgroundColor = node.backgroundColor;
-  self.clipsToBounds = node.clipsToBounds;
-  [node __setSelectedFromUIKit:self.selected];
-  [node __setHighlightedFromUIKit:self.highlighted];
-}
-
-- (void)setSelected:(BOOL)selected
-{
-  [super setSelected:selected];
-  [_node __setSelectedFromUIKit:selected];
-}
-
-- (void)setHighlighted:(BOOL)highlighted
-{
-  [super setHighlighted:highlighted];
-  [_node __setHighlightedFromUIKit:highlighted];
-}
-
-- (void)setLayoutAttributes:(UICollectionViewLayoutAttributes *)layoutAttributes
-{
-  _layoutAttributes = layoutAttributes;
-  _node.layoutAttributes = layoutAttributes;
-}
-
-- (void)prepareForReuse
-{
-  self.layoutAttributes = nil;
-
-  // Need to clear node pointer before UIKit calls setSelected:NO / setHighlighted:NO on its cells
-  self.node = nil;
-  [super prepareForReuse];
-}
-
-/**
- * In the initial case, this is called by UICollectionView during cell dequeueing, before
- *   we get a chance to assign a node to it, so we must be sure to set these layout attributes
- *   on our node when one is next assigned to us in @c setNode: . Since there may be cases when we _do_ already
- *   have our node assigned e.g. during a layout update for existing cells, we also attempt
- *   to update it now.
- */
-- (void)applyLayoutAttributes:(UICollectionViewLayoutAttributes *)layoutAttributes
-{
-  self.layoutAttributes = layoutAttributes;
-}
-
-/**
- * Keep our node filling our content view.
- */
-- (void)layoutSubviews
-{
-  [super layoutSubviews];
-  self.node.frame = self.contentView.bounds;
-}
-
-@end
-
 #pragma mark -
 #pragma mark ASCollectionView.
 
@@ -243,8 +177,9 @@ static NSString * const kReuseIdentifier = @"_ASCollectionReuseIdentifier";
     unsigned int collectionNodeWillBeginBatchFetch:1;
     unsigned int collectionNodeWillDisplaySupplementaryElement:1;
     unsigned int collectionNodeDidEndDisplayingSupplementaryElement:1;
-
     unsigned int shouldBatchFetchForCollectionNode:1;
+    // Whether this delegate conforms to ASCollectionDataSourceInterop
+    unsigned int interop:1;
   } _asyncDelegateFlags;
   
   struct {
@@ -256,9 +191,13 @@ static NSString * const kReuseIdentifier = @"_ASCollectionReuseIdentifier";
     unsigned int collectionNodeNodeForItem:1;
     unsigned int collectionNodeNodeBlockForItem:1;
     unsigned int collectionNodeNodeForSupplementaryElement:1;
+    unsigned int collectionNodeSupplementaryElementKindsInSection:1;
     unsigned int numberOfSectionsInCollectionNode:1;
     unsigned int collectionNodeNumberOfItemsInSection:1;
     unsigned int collectionNodeContextForSection:1;
+
+    // Whether this data source conforms to ASCollectionDataSourceInterop
+    unsigned int interop:1;
   } _asyncDataSourceFlags;
   
   struct {
@@ -267,8 +206,6 @@ static NSString * const kReuseIdentifier = @"_ASCollectionReuseIdentifier";
   } _layoutInspectorFlags;
 }
 
-@property (nonatomic, weak)   ASCollectionNode *collectionNode;
-
 @end
 
 @interface ASCollectionNode ()
@@ -426,14 +363,14 @@ static NSString * const kReuseIdentifier = @"_ASCollectionReuseIdentifier";
 
 - (void)setDataSource:(id<UICollectionViewDataSource>)dataSource
 {
-  // UIKit can internally generate a call to this method upon changing the asyncDataSource; only assert for non-nil.
+  // UIKit can internally generate a call to this method upon changing the asyncDataSource; only assert for non-nil. We also allow this when we're doing interop.
-  ASDisplayNodeAssert(dataSource == nil, @"ASCollectionView uses asyncDataSource, not UICollectionView's dataSource property.");
+  ASDisplayNodeAssert(_asyncDelegateFlags.interop || dataSource == nil, @"ASCollectionView uses asyncDataSource, not UICollectionView's dataSource property.");
 }
 
 - (void)setDelegate:(id<UICollectionViewDelegate>)delegate
 {
-  // Our UIScrollView superclass sets its delegate to nil on dealloc. Only assert if we get a non-nil value here.
+  // Our UIScrollView superclass sets its delegate to nil on dealloc. Only assert if we get a non-nil value here. We also allow this when we're doing interop.
-  ASDisplayNodeAssert(delegate == nil, @"ASCollectionView uses asyncDelegate, not UICollectionView's delegate property.");
+  ASDisplayNodeAssert(_asyncDelegateFlags.interop || delegate == nil, @"ASCollectionView uses asyncDelegate, not UICollectionView's delegate property.");
 }
 
 - (void)proxyTargetHasDeallocated:(ASDelegateProxy *)proxy
@@ -464,8 +401,8 @@ static NSString * const kReuseIdentifier = @"_ASCollectionReuseIdentifier";
   if (asyncDataSource == nil) {
     _asyncDataSource = nil;
     _proxyDataSource = _isDeallocating ? nil : [[ASCollectionViewProxy alloc] initWithTarget:nil interceptor:self];
-    
+    _asyncDataSourceFlags = {};
-    memset(&_asyncDataSourceFlags, 0, sizeof(_asyncDataSourceFlags));
+
   } else {
     _asyncDataSource = asyncDataSource;
     _proxyDataSource = [[ASCollectionViewProxy alloc] initWithTarget:_asyncDataSource interceptor:self];
@@ -482,7 +419,8 @@ static NSString * const kReuseIdentifier = @"_ASCollectionReuseIdentifier";
     _asyncDataSourceFlags.collectionNodeNumberOfItemsInSection = [_asyncDataSource respondsToSelector:@selector(collectionNode:numberOfItemsInSection:)];
     _asyncDataSourceFlags.collectionNodeContextForSection = [_asyncDataSource respondsToSelector:@selector(collectionNode:contextForSection:)];
     _asyncDataSourceFlags.collectionNodeNodeForSupplementaryElement = [_asyncDataSource respondsToSelector:@selector(collectionNode:nodeForSupplementaryElementOfKind:atIndexPath:)];
-
+    _asyncDataSourceFlags.collectionNodeSupplementaryElementKindsInSection = [_asyncDataSource respondsToSelector:@selector(collectionNode:supplementaryElementKindsInSection:)];
+    _asyncDataSourceFlags.interop = [_asyncDataSource conformsToProtocol:@protocol(ASCollectionDataSourceInterop)];
 
     ASDisplayNodeAssert(_asyncDataSourceFlags.collectionNodeNumberOfItemsInSection || _asyncDataSourceFlags.collectionViewNumberOfItemsInSection, @"Data source must implement collectionNode:numberOfItemsInSection:");
     ASDisplayNodeAssert(_asyncDataSourceFlags.collectionNodeNodeBlockForItem
@@ -520,8 +458,7 @@ static NSString * const kReuseIdentifier = @"_ASCollectionReuseIdentifier";
   if (asyncDelegate == nil) {
     _asyncDelegate = nil;
     _proxyDelegate = _isDeallocating ? nil : [[ASCollectionViewProxy alloc] initWithTarget:nil interceptor:self];
-    
+    _asyncDataSourceFlags = {};
-    memset(&_asyncDelegateFlags, 0, sizeof(_asyncDelegateFlags));
   } else {
     _asyncDelegate = asyncDelegate;
     _proxyDelegate = [[ASCollectionViewProxy alloc] initWithTarget:_asyncDelegate interceptor:self];
@@ -561,6 +498,7 @@ static NSString * const kReuseIdentifier = @"_ASCollectionReuseIdentifier";
     _asyncDelegateFlags.collectionNodeShouldShowMenuForItem = [_asyncDelegate respondsToSelector:@selector(collectionNode:shouldShowMenuForItemAtIndexPath:)];
     _asyncDelegateFlags.collectionNodeCanPerformActionForItem = [_asyncDelegate respondsToSelector:@selector(collectionNode:canPerformAction:forItemAtIndexPath:sender:)];
     _asyncDelegateFlags.collectionNodePerformActionForItem = [_asyncDelegate respondsToSelector:@selector(collectionNode:performAction:forItemAtIndexPath:sender:)];
+    _asyncDelegateFlags.interop = [_asyncDelegate conformsToProtocol:@protocol(ASCollectionDelegateInterop)];
   }
 
   super.delegate = (id<UICollectionViewDelegate>)_proxyDelegate;
@@ -939,7 +877,13 @@ static NSString * const kReuseIdentifier = @"_ASCollectionReuseIdentifier";
 
 - (UICollectionReusableView *)collectionView:(UICollectionView *)collectionView viewForSupplementaryElementOfKind:(NSString *)kind atIndexPath:(NSIndexPath *)indexPath
 {
-  UICollectionReusableView *view = [self dequeueReusableSupplementaryViewOfKind:kind withReuseIdentifier:kReuseIdentifier forIndexPath:indexPath];
+  UICollectionReusableView *view;
+  if (_asyncDataSource && _asyncDataSourceFlags.interop) {
+    view = [(id<ASCollectionDataSourceInterop>)_asyncDataSource collectionView:collectionView viewForSupplementaryElementOfKind:kind atIndexPath:indexPath];
+  } else {
+    view = [self dequeueReusableSupplementaryViewOfKind:kind withReuseIdentifier:kReuseIdentifier forIndexPath:indexPath];
+  }
+  
   ASCellNode *node = [_dataController supplementaryNodeOfKind:kind atIndexPath:indexPath];
   ASDisplayNodeAssert(node != nil, @"Supplementary node should exist.  Kind = %@, indexPath = %@, collectionDataSource = %@", kind, indexPath, self);
   [_rangeController configureContentView:view forCellNode:node];
@@ -948,7 +892,12 @@ static NSString * const kReuseIdentifier = @"_ASCollectionReuseIdentifier";
 
 - (UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath
 {
-  _ASCollectionViewCell *cell = [self dequeueReusableCellWithReuseIdentifier:kReuseIdentifier forIndexPath:indexPath];
+  _ASCollectionViewCell *cell;
+  if (_asyncDataSource && _asyncDataSourceFlags.interop) {
+    cell = [(id<ASCollectionDataSourceInterop>)_asyncDataSource collectionView:collectionView cellForItemAtIndexPath:indexPath];
+  } else {
+    cell = [self dequeueReusableCellWithReuseIdentifier:kReuseIdentifier forIndexPath:indexPath];
+  }
   
   ASCellNode *node = [self nodeForItemAtIndexPath:indexPath];
   cell.node = node;
@@ -979,7 +928,9 @@ static NSString * const kReuseIdentifier = @"_ASCollectionReuseIdentifier";
 
   ASDisplayNodeAssertNotNil(cellNode, @"Expected node associated with cell that will be displayed not to be nil. indexPath: %@", indexPath);
 
-  if (_asyncDelegateFlags.collectionNodeWillDisplayItem) {
+  if (_asyncDelegateFlags.interop) {
+    [(id<ASCollectionDelegateInterop>)_asyncDelegate collectionView:collectionView willDisplayCell:cell forItemAtIndexPath:indexPath];
+  } else if (_asyncDelegateFlags.collectionNodeWillDisplayItem) {
     if (ASCollectionNode *collectionNode = self.collectionNode) {
     	[_asyncDelegate collectionNode:collectionNode willDisplayItemWithNode:cellNode];
     }
@@ -1004,7 +955,9 @@ static NSString * const kReuseIdentifier = @"_ASCollectionReuseIdentifier";
   ASCellNode *cellNode = [cell node];
   ASDisplayNodeAssertNotNil(cellNode, @"Expected node associated with removed cell not to be nil.");
 
-  if (_asyncDelegateFlags.collectionNodeDidEndDisplayingItem) {
+  if (_asyncDelegateFlags.interop) {
+    [(id<ASCollectionDelegateInterop>)_asyncDelegate collectionView:collectionView didEndDisplayingCell:cell forItemAtIndexPath:indexPath];
+  } else if (_asyncDelegateFlags.collectionNodeDidEndDisplayingItem) {
     if (ASCollectionNode *collectionNode = self.collectionNode) {
     	[_asyncDelegate collectionNode:collectionNode didEndDisplayingItemWithNode:cellNode];
     }
@@ -1544,10 +1497,20 @@ static NSString * const kReuseIdentifier = @"_ASCollectionReuseIdentifier";
   return node;
 }
 
-// TODO: Lock this
+- (NSArray *)supplementaryNodeKindsInDataController:(ASCollectionDataController *)dataController sections:(NSIndexSet *)sections
-- (NSArray *)supplementaryNodeKindsInDataController:(ASCollectionDataController *)dataController
 {
-  return [_registeredSupplementaryKinds allObjects];
+  if (_asyncDataSourceFlags.collectionNodeSupplementaryElementKindsInSection) {
+    NSMutableSet *kinds = [NSMutableSet set];
+    GET_COLLECTIONNODE_OR_RETURN(collectionNode, @[]);
+    [sections enumerateIndexesUsingBlock:^(NSUInteger section, BOOL * _Nonnull stop) {
+      NSArray *kindsForSection = [_asyncDataSource collectionNode:collectionNode supplementaryElementKindsInSection:section];
+      [kinds addObjectsFromArray:kindsForSection];
+    }];
+    return [kinds allObjects];
+  } else {
+    // TODO: Lock this
+    return [_registeredSupplementaryKinds allObjects];
+  }
 }
 
 - (ASSizeRange)dataController:(ASCollectionDataController *)dataController constrainedSizeForSupplementaryNodeOfKind:(NSString *)kind atIndexPath:(NSIndexPath *)indexPath

AsyncDisplayKit/ASCollectionViewProtocols.h

@@ -23,7 +23,7 @@ NS_ASSUME_NONNULL_BEGIN
 
 - (NSInteger)numberOfSectionsInCollectionView:(UICollectionView *)collectionView ASDISPLAYNODE_DEPRECATED_MSG("Implement -numberOfSectionsInCollectionNode: instead.");
 
-- (UICollectionReusableView *)collectionView:(UICollectionView *)collectionView viewForSupplementaryElementOfKind:(NSString *)kind atIndexPath:(NSIndexPath *)indexPath ASDISPLAYNODE_DEPRECATED_MSG("Implement - collectionNode:viewForSupplementaryElementOfKind:atIndexPath: instead.");
+- (UICollectionReusableView *)collectionView:(UICollectionView *)collectionView viewForSupplementaryElementOfKind:(NSString *)kind atIndexPath:(NSIndexPath *)indexPath ASDISPLAYNODE_DEPRECATED_MSG("Implement - collectionNode:nodeForSupplementaryElementOfKind:atIndexPath: instead.");
 
 @end
 

AsyncDisplayKit/ASDisplayNode.mm

@@ -389,11 +389,10 @@ static ASDisplayNodeMethodOverrides GetASDisplayNodeMethodOverrides(Class c)
 {
   ASDN::MutexLocker l(__instanceLock__);
   if ([self _isNodeLoaded]) {
-    ASDisplayNodeFailAssert(@"Attempt to call %@ on node after it was loaded. Node: %@", NSStringFromSelector(_cmd), self);
+    ASDisplayNodeAssertThreadAffinity(self);
-    return;
+    ASDN::MutexUnlocker l(__instanceLock__);
-  }
+    body(self);
-  
+  } else if (_onDidLoadBlocks == nil) {
-  if (_onDidLoadBlocks == nil) {
     _onDidLoadBlocks = [NSMutableArray arrayWithObject:body];
   } else {
     [_onDidLoadBlocks addObject:body];
@@ -663,11 +662,11 @@ static ASDisplayNodeMethodOverrides GetASDisplayNodeMethodOverrides(Class c)
   ASDN::MutexLocker l(__instanceLock__);
 
   ASDisplayNodeLogEvent(self, @"didLoad");
+  [self didLoad];
   for (ASDisplayNodeDidLoadBlock block in _onDidLoadBlocks) {
     block(self);
   }
   _onDidLoadBlocks = nil;
-  [self didLoad];
 }
 
 - (void)didLoad

AsyncDisplayKit/ASIGListKitMethodImplementations.h

@@ -0,0 +1,66 @@
+//
+//  ASIGListKitMethodImplementations.h
+//  AsyncDisplayKit
+//
+//  Created by Adlai Holler on 1/19/17.
+//  Copyright © 2017 Facebook. All rights reserved.
+//
+
+/**
+ * If you are using AsyncDisplayKit with IGListKit, you should use
+ * these macros to provide implementations of methods like 
+ * -cellForItemAtIndex: that don't apply when used with AsyncDisplayKit.
+ *
+ * Your section controllers should also conform to @c ASSectionController and your
+ * supplementary view sources should conform to @c ASSupplementaryNodeSource.
+ */
+
+#if IG_LIST_KIT
+
+#import <AsyncDisplayKit/_ASCollectionViewCell.h>
+
+/**
+ * The implementation of viewForSupplementaryElementOfKind that connects
+ * IGSupplementaryViewSource to AsyncDisplayKit. Add this into the .m file
+ * for your `ASIGListSupplementaryViewSource` and implement the ASDK-specific
+ * method `nodeForSupplementaryElementOfKind:` to provide your node.
+ *
+ * @param sectionController The section controller this supplementary source is
+ * working on behalf of. For example, `self` or `self.sectionController`.
+ */
+#define ASIGSupplementarySourceViewForSupplementaryElementImplementation(sectionController) \
+- (__kindof UICollectionReusableView *)viewForSupplementaryElementOfKind:(NSString *)elementKind atIndex:(NSInteger)index { \
+  return [self.collectionContext dequeueReusableSupplementaryViewOfKind:elementKind forSectionController:sectionController class:[UICollectionReusableView class] atIndex:index]; \
+}
+
+/**
+ * The implementation of sizeForSupplementaryViewOfKind that connects
+ * IGSupplementaryViewSource to AsyncDisplayKit. Add this into the .m file
+ * for your `ASIGListSupplementaryViewSource` and implement the ASDK-specific
+ * method `nodeForSupplementaryElementOfKind:` to provide your node which should
+ * size itself. You can set `node.style.preferredSize` if you want to fix the size.
+ *
+ * @param sectionController The section controller this supplementary source is
+ * working on behalf of. For example, `self` or `self.sectionController`.
+ */
+#define ASIGSupplementarySourceSizeForSupplementaryElementImplementation \
+- (CGSize)sizeForSupplementaryViewOfKind:(NSString *)elementKind atIndex:(NSInteger)index {\
+  ASDisplayNodeFailAssert(@"Did not expect %@ to be called.", NSStringFromSelector(_cmd)); \
+  return CGSizeZero; \
+}
+
+
+#define ASIGSectionControllerCellForIndexImplementation \
+- (__kindof UICollectionViewCell *)cellForItemAtIndex:(NSInteger)index\
+{\
+  return [self.collectionContext dequeueReusableCellOfClass:[_ASCollectionViewCell class] forSectionController:self atIndex:index]; \
+}\
+
+#define ASIGSectionControllerSizeForItemImplementation \
+- (CGSize)sizeForItemAtIndex:(NSInteger)index \
+{\
+  ASDisplayNodeFailAssert(@"Did not expect %@ to be called.", NSStringFromSelector(_cmd)); \
+  return CGSizeZero;\
+}
+
+#endif // IG_LIST_KIT

AsyncDisplayKit/ASSectionController.h

@@ -0,0 +1,69 @@
+//
+//  ASSectionController.h
+//  AsyncDisplayKit
+//
+//  Created by Adlai Holler on 1/19/17.
+//  Copyright © 2017 Facebook. All rights reserved.
+//
+
+#import <Foundation/Foundation.h>
+
+NS_ASSUME_NONNULL_BEGIN
+
+/**
+ * A protocol that your section controllers should conform to,
+ * in addition to IGListSectionType, in order to be used with AsyncDisplayKit.
+ *
+ * @note Your supplementary view source should conform to @c ASSupplementaryNodeSource.
+ */
+@protocol ASSectionController <NSObject>
+
+/**
+ * A method to provide the node block for the item at the given index.
+ * The node block you return will be run asynchronously off the main thread,
+ * so it's important to retrieve any objects from your section _outside_ the block
+ * because by the time the block is run, the array may have changed.
+ *
+ * @param index The index of the item.
+ * @return A block to be run concurrently to build the node for this item.
+ * @see collectionNode:nodeBlockForItemAtIndexPath:
+ */
+- (ASCellNodeBlock)nodeBlockForItemAtIndex:(NSInteger)index;
+
+@optional
+
+/**
+ * Asks the section controller whether it should batch fetch because the user is
+ * near the end of the current data set.
+ *
+ * @discussion Use this method to conditionally fetch batches. Example use cases are: limiting the total number of
+ * objects that can be fetched or no network connection.
+ *
+ * If not implemented, the assumed return value is @c YES.
+ */
+- (BOOL)shouldBatchFetch;
+
+/**
+ * Asks the section controller to begin fetching more content (tail loading) because
+ * the user is near the end of the current data set.
+ *
+ * @param context A context object that must be notified when the batch fetch is completed.
+ *
+ * @discussion You must eventually call -completeBatchFetching: with an argument of YES in order to receive future
+ * notifications to do batch fetches. This method is called on a background queue.
+ */
+- (void)beginBatchFetchWithContext:(ASBatchContext *)context;
+
+/**
+ * A method to provide the size range used for measuring the item
+ * at the given index.
+ *
+ * @param index The index of the item.
+ * @return A size range used for asynchronously measuring the node at this index.
+ * @see collectionNode:constrainedSizeForItemAtIndexPath:
+ */
+- (ASSizeRange)sizeRangeForItemAtIndex:(NSInteger)index;
+
+@end
+
+NS_ASSUME_NONNULL_END

AsyncDisplayKit/ASSupplementaryNodeSource.h

@@ -0,0 +1,40 @@
+//
+//  ASSupplementaryNodeSource.h
+//  AsyncDisplayKit
+//
+//  Created by Adlai Holler on 1/19/17.
+//  Copyright © 2017 Facebook. All rights reserved.
+//
+
+#import <Foundation/Foundation.h>
+
+NS_ASSUME_NONNULL_BEGIN
+
+@protocol ASSupplementaryNodeSource <NSObject>
+
+/**
+ * A method to provide the node for the item at the given index.
+ *
+ * @param elementKind The kind of supplementary element.
+ * @param index The index of the item.
+ * @return A node for the supplementary element.
+ * @see collectionNode:nodeForSupplementaryElementOfKind:atIndexPath:
+ */
+- (ASCellNode *)nodeForSupplementaryElementOfKind:(NSString *)elementKind atIndex:(NSInteger)index;
+
+@optional
+
+/**
+ * A method to provide the size range used for measuring the supplementary
+ * element of the given kind at the given index.
+ *
+ * @param elementKind The kind of supplementary element.
+ * @param index The index of the item.
+ * @return A size range used for asynchronously measuring the node.
+ * @see collectionNode:constrainedSizeForSupplementaryElementOfKind:atIndexPath:
+ */
+- (ASSizeRange)sizeRangeForSupplementaryElementOfKind:(NSString *)elementKind atIndex:(NSInteger)index;
+
+@end
+
+NS_ASSUME_NONNULL_END

AsyncDisplayKit/AsyncDisplayKit-Prefix.pch

@@ -17,3 +17,7 @@
 // a user does not include the framework in the link binary with build step).
 #define PIN_REMOTE_IMAGE __has_include(<PINRemoteImage/PINRemoteImage.h>)
 #endif
+
+#ifndef IG_LIST_KIT
+#define IG_LIST_KIT __has_include(<IGListKit/IGListKit.h>)
+#endif

AsyncDisplayKit/AsyncDisplayKit.h

@@ -34,6 +34,13 @@
 #import <AsyncDisplayKit/ASCellNode.h>
 #import <AsyncDisplayKit/ASSectionContext.h>
 
+#import <AsyncDisplayKit/ASSectionController.h>
+#import <AsyncDisplayKit/ASSupplementaryNodeSource.h>
+#if IG_LIST_KIT
+#import <AsyncDisplayKit/IGListAdapter+AsyncDisplayKit.h>
+#import <AsyncDisplayKit/ASIGListKitMethodImplementations.h>
+#endif
+
 #import <AsyncDisplayKit/ASScrollNode.h>
 
 #import <AsyncDisplayKit/ASPagerFlowLayout.h>

AsyncDisplayKit/Details/ASCollectionDataController.h

@@ -27,7 +27,7 @@ NS_ASSUME_NONNULL_BEGIN
  */
 - (ASSizeRange)dataController:(ASCollectionDataController *)dataController constrainedSizeForSupplementaryNodeOfKind:(NSString *)kind atIndexPath:(NSIndexPath *)indexPath;
 
-- (NSArray *)supplementaryNodeKindsInDataController:(ASCollectionDataController *)dataController;
+- (NSArray *)supplementaryNodeKindsInDataController:(ASCollectionDataController *)dataController sections:(NSIndexSet *)sections;
 
 - (NSUInteger)dataController:(ASCollectionDataController *)dataController supplementaryNodesOfKind:(NSString *)kind inSection:(NSUInteger)section;
 

AsyncDisplayKit/Details/ASCollectionDataController.mm

@@ -17,6 +17,7 @@
 #import "ASIndexedNodeContext.h"
 #import "ASSection.h"
 #import "ASSectionContext.h"
+#import "NSIndexSet+ASHelpers.h"
 
 //#define LOG(...) NSLog(__VA_ARGS__)
 #define LOG(...)
@@ -26,6 +27,13 @@
   NSInteger _nextSectionID;
   NSMutableArray<ASSection *> *_sections;
   NSArray<ASSection *> *_pendingSections;
+
+  /**
+   * supplementaryKinds can only be accessed on the main thread
+   * and so we set this in the -prepare stage, and then read it during the -will
+   * stage of each update operation.
+   */
+  NSArray *_supplementaryKindsForPendingOperation;
 }
 
 - (id<ASCollectionDataControllerSource>)collectionDataSource;
@@ -59,7 +67,7 @@
   [_sections removeAllObjects];
   [self _populatePendingSectionsFromDataSource:sections];
   
-  for (NSString *kind in [self supplementaryKinds]) {
+  for (NSString *kind in [self supplementaryKindsInSections:sections]) {
     LOG(@"Populating elements of kind: %@", kind);
     NSMutableArray<ASIndexedNodeContext *> *contexts = [NSMutableArray array];
     [self _populateSupplementaryNodesOfKind:kind withSections:sections mutableContexts:contexts];
@@ -101,7 +109,7 @@
   ASDisplayNodeAssertMainThread();
   [self _populatePendingSectionsFromDataSource:sections];
   
-  for (NSString *kind in [self supplementaryKinds]) {
+  for (NSString *kind in [self supplementaryKindsInSections:sections]) {
     LOG(@"Populating elements of kind: %@, for sections: %@", kind, sections);
     NSMutableArray<ASIndexedNodeContext *> *contexts = [NSMutableArray array];
     [self _populateSupplementaryNodesOfKind:kind withSections:sections mutableContexts:contexts];
@@ -127,46 +135,29 @@
   [_pendingNodeContexts removeAllObjects];
 }
 
+- (void)prepareForDeleteSections:(NSIndexSet *)sections
+{
+  _supplementaryKindsForPendingOperation = [self supplementaryKindsInSections:sections];
+}
+
 - (void)willDeleteSections:(NSIndexSet *)sections
 {
   [_sections removeObjectsAtIndexes:sections];
-  
+
-  for (NSString *kind in [self supplementaryKinds]) {
+  for (NSString *kind in _supplementaryKindsForPendingOperation) {
     NSArray *indexPaths = ASIndexPathsForMultidimensionalArrayAtIndexSet([self editingNodesOfKind:kind], sections);
     
     [self deleteNodesOfKind:kind atIndexPaths:indexPaths completion:nil];
     [self deleteSectionsOfKind:kind atIndexSet:sections completion:nil];
   }
-}
+  _supplementaryKindsForPendingOperation = nil;
-
-- (void)willMoveSection:(NSInteger)section toSection:(NSInteger)newSection
-{
-  ASSection *movedSection = [_sections objectAtIndex:section];
-  [_sections removeObjectAtIndex:section];
-  [_sections insertObject:movedSection atIndex:newSection];
-  
-  NSIndexSet *sectionAsIndexSet = [NSIndexSet indexSetWithIndex:section];
-  for (NSString *kind in [self supplementaryKinds]) {
-    NSMutableArray *editingNodes = [self editingNodesOfKind:kind];
-    NSArray *indexPaths = ASIndexPathsForMultidimensionalArrayAtIndexSet(editingNodes, sectionAsIndexSet);
-    NSArray *nodes = ASFindElementsInMultidimensionalArrayAtIndexPaths(editingNodes, indexPaths);
-    [self deleteNodesOfKind:kind atIndexPaths:indexPaths completion:nil];
-    
-    // update the section of indexpaths
-    NSMutableArray *updatedIndexPaths = [[NSMutableArray alloc] initWithCapacity:indexPaths.count];
-    for (NSIndexPath *indexPath in indexPaths) {
-      NSUInteger newItem = [indexPath indexAtPosition:indexPath.length - 1];
-      NSIndexPath *mappedIndexPath = [NSIndexPath indexPathForItem:newItem inSection:newSection];
-      [updatedIndexPaths addObject:mappedIndexPath];
-    }
-    [self insertNodes:nodes ofKind:kind atIndexPaths:indexPaths completion:nil];
-  }
 }
 
 - (void)prepareForInsertRowsAtIndexPaths:(NSArray<NSIndexPath *> *)indexPaths
 {
   ASDisplayNodeAssertMainThread();
-  for (NSString *kind in [self supplementaryKinds]) {
+  NSIndexSet *sections = [NSIndexSet as_sectionsFromIndexPaths:indexPaths];
+  for (NSString *kind in [self supplementaryKindsInSections:sections]) {
     LOG(@"Populating elements of kind: %@, for index paths: %@", kind, indexPaths);
     NSMutableArray<ASIndexedNodeContext *> *contexts = [NSMutableArray array];
     [self _populateSupplementaryNodesOfKind:kind atIndexPaths:indexPaths mutableContexts:contexts];
@@ -188,7 +179,9 @@
 - (void)prepareForDeleteRowsAtIndexPaths:(NSArray<NSIndexPath *> *)indexPaths
 {
   ASDisplayNodeAssertMainThread();
-  for (NSString *kind in [self supplementaryKinds]) {
+  NSIndexSet *sections = [NSIndexSet as_sectionsFromIndexPaths:indexPaths];
+  _supplementaryKindsForPendingOperation = [self supplementaryKindsInSections:sections];
+  for (NSString *kind in _supplementaryKindsForPendingOperation) {
     NSMutableArray<ASIndexedNodeContext *> *contexts = [NSMutableArray array];
     [self _populateSupplementaryNodesOfKind:kind atIndexPaths:indexPaths mutableContexts:contexts];
     _pendingNodeContexts[kind] = contexts;
@@ -197,7 +190,7 @@
 
 - (void)willDeleteRowsAtIndexPaths:(NSArray<NSIndexPath *> *)indexPaths
 {
-  for (NSString *kind in [self supplementaryKinds]) {
+  for (NSString *kind in _supplementaryKindsForPendingOperation) {
     NSArray<NSIndexPath *> *deletedIndexPaths = ASIndexPathsInMultidimensionalArrayIntersectingIndexPaths([self editingNodesOfKind:kind], indexPaths);
 
     [self deleteNodesOfKind:kind atIndexPaths:deletedIndexPaths completion:nil];
@@ -216,6 +209,7 @@
     }];
   }
   [_pendingNodeContexts removeAllObjects];
+  _supplementaryKindsForPendingOperation = nil;
 }
 
 - (void)_populatePendingSectionsFromDataSource:(NSIndexSet *)sectionIndexes
@@ -323,9 +317,9 @@
 
 #pragma mark - Private Helpers
 
-- (NSArray *)supplementaryKinds
+- (NSArray *)supplementaryKindsInSections:(NSIndexSet *)sections
 {
-  return [self.collectionDataSource supplementaryNodeKindsInDataController:self];
+  return [self.collectionDataSource supplementaryNodeKindsInDataController:self sections:sections];
 }
 
 - (id<ASCollectionDataControllerSource>)collectionDataSource

AsyncDisplayKit/Details/ASCollectionViewFlowLayoutInspector.m

@@ -66,24 +66,32 @@
 
 - (ASSizeRange)collectionView:(ASCollectionView *)collectionView constrainedSizeForNodeAtIndexPath:(NSIndexPath *)indexPath
 {
+  ASSizeRange result = ASSizeRangeUnconstrained;
   if (_delegateFlags.implementsConstrainedSizeForItemAtIndexPath) {
-    return [collectionView.asyncDelegate collectionNode:collectionView.collectionNode constrainedSizeForItemAtIndexPath:indexPath];
+    result = [collectionView.asyncDelegate collectionNode:collectionView.collectionNode constrainedSizeForItemAtIndexPath:indexPath];
   } else if (_delegateFlags.implementsConstrainedSizeForNodeAtIndexPathDeprecated) {
 #pragma clang diagnostic push
 #pragma clang diagnostic ignored "-Wdeprecated-declarations"
-    return [collectionView.asyncDelegate collectionView:collectionView constrainedSizeForNodeAtIndexPath:indexPath];
+    result = [collectionView.asyncDelegate collectionView:collectionView constrainedSizeForNodeAtIndexPath:indexPath];
 #pragma clang diagnostic pop
   } else {
     // With 2.0 `collectionView:constrainedSizeForNodeAtIndexPath:` was moved to the delegate. Assert if not implemented on the delegate but on the data source
     ASDisplayNodeAssert([collectionView.asyncDataSource respondsToSelector:@selector(collectionView:constrainedSizeForNodeAtIndexPath:)] == NO, @"collectionView:constrainedSizeForNodeAtIndexPath: was moved from the ASCollectionDataSource to the ASCollectionDelegate.");
   }
-  
+
-  CGSize itemSize = _layout.itemSize;
+  // If we got no size range:
-  if (CGSizeEqualToSize(itemSize, kDefaultItemSize) == NO) {
+  if (ASSizeRangeEqualToSizeRange(result, ASSizeRangeUnconstrained)) {
-    return ASSizeRangeMake(itemSize, itemSize);
+    // Use itemSize if they set it.
+    CGSize itemSize = _layout.itemSize;
+    if (CGSizeEqualToSize(itemSize, kDefaultItemSize) == NO) {
+      result = ASSizeRangeMake(itemSize, itemSize);
+    } else {
+      // Compute constraint from scroll direction otherwise.
+      result = NodeConstrainedSizeForScrollDirection(collectionView);
+    }
   }
   
-  return NodeConstrainedSizeForScrollDirection(collectionView);
+  return result;
 }
 
 - (ASSizeRange)collectionView:(ASCollectionView *)collectionView constrainedSizeForSupplementaryNodeOfKind:(NSString *)kind atIndexPath:(NSIndexPath *)indexPath

AsyncDisplayKit/Details/ASCollectionViewLayoutInspector.m

@@ -10,6 +10,7 @@
 
 #import "ASCollectionView.h"
 #import "ASCollectionView+Undeprecated.h"
+#import "ASCollectionInternal.h"
 
 #pragma mark - Helper Functions
 

AsyncDisplayKit/Details/ASDataController.mm

@@ -719,6 +719,8 @@ NSString * const ASCollectionInvalidUpdateException = @"ASCollectionInvalidUpdat
   [_nodeContexts[ASDataControllerRowNodeKind] removeObjectsAtIndexes:sections];
 
   dispatch_group_wait(_editingTransactionGroup, DISPATCH_TIME_FOREVER);
+
+  [self prepareForDeleteSections:sections];
   dispatch_group_async(_editingTransactionGroup, _editingTransactionQueue, ^{
     [self willDeleteSections:sections];
 
@@ -745,6 +747,11 @@ NSString * const ASCollectionInvalidUpdateException = @"ASCollectionInvalidUpdat
   // Optional template hook for subclasses (See ASDataController+Subclasses.h)
 }
 
+- (void)prepareForDeleteSections:(NSIndexSet *)sections
+{
+  // Optional template hook for subclasses (See ASDataController+Subclasses.h)
+}
+
 - (void)willInsertSections:(NSIndexSet *)sections
 {
   // Optional template hook for subclasses (See ASDataController+Subclasses.h)

AsyncDisplayKit/Details/NSIndexSet+ASHelpers.h

@@ -22,4 +22,7 @@
 
 - (NSString *)as_smallDescription;
 
+/// Returns all the section indexes contained in the index paths array.
++ (NSIndexSet *)as_sectionsFromIndexPaths:(NSArray<NSIndexPath *> *)indexPaths;
+
 @end

AsyncDisplayKit/Details/NSIndexSet+ASHelpers.m

@@ -77,4 +77,13 @@
   return result;
 }
 
++ (NSIndexSet *)as_sectionsFromIndexPaths:(NSArray<NSIndexPath *> *)indexPaths
+{
+  NSMutableIndexSet *result = [NSMutableIndexSet indexSet];
+  for (NSIndexPath *indexPath in indexPaths) {
+    [result addIndex:indexPath.section];
+  }
+  return result;
+}
+
 @end

AsyncDisplayKit/Details/_ASCollectionViewCell.h

@@ -0,0 +1,17 @@
+//
+//  _ASCollectionViewCell.h
+//  AsyncDisplayKit
+//
+//  Created by Adlai Holler on 1/30/17.
+//  Copyright © 2017 Facebook. All rights reserved.
+//
+
+#import <UIKit/UIKit.h>
+
+@class ASCellNode;
+
+@interface _ASCollectionViewCell : UICollectionViewCell
+@property (nonatomic, weak) ASCellNode *node;
+@property (nonatomic, strong) UICollectionViewLayoutAttributes *layoutAttributes;
+@end
+

AsyncDisplayKit/Details/_ASCollectionViewCell.m

@@ -0,0 +1,74 @@
+//
+//  _ASCollectionViewCell.m
+//  AsyncDisplayKit
+//
+//  Created by Adlai Holler on 1/30/17.
+//  Copyright © 2017 Facebook. All rights reserved.
+//
+
+#import "_ASCollectionViewCell.h"
+#import "ASCellNode+Internal.h"
+#import <AsyncDisplayKit/AsyncDisplayKit.h>
+
+@implementation _ASCollectionViewCell
+
+- (void)setNode:(ASCellNode *)node
+{
+  ASDisplayNodeAssertMainThread();
+  node.layoutAttributes = _layoutAttributes;
+  _node = node;
+  self.backgroundColor = node.backgroundColor;
+  self.clipsToBounds = node.clipsToBounds;
+  [node __setSelectedFromUIKit:self.selected];
+  [node __setHighlightedFromUIKit:self.highlighted];
+}
+
+- (void)setSelected:(BOOL)selected
+{
+  [super setSelected:selected];
+  [_node __setSelectedFromUIKit:selected];
+}
+
+- (void)setHighlighted:(BOOL)highlighted
+{
+  [super setHighlighted:highlighted];
+  [_node __setHighlightedFromUIKit:highlighted];
+}
+
+- (void)setLayoutAttributes:(UICollectionViewLayoutAttributes *)layoutAttributes
+{
+  _layoutAttributes = layoutAttributes;
+  _node.layoutAttributes = layoutAttributes;
+}
+
+- (void)prepareForReuse
+{
+  self.layoutAttributes = nil;
+
+  // Need to clear node pointer before UIKit calls setSelected:NO / setHighlighted:NO on its cells
+  self.node = nil;
+  [super prepareForReuse];
+}
+
+/**
+ * In the initial case, this is called by UICollectionView during cell dequeueing, before
+ *   we get a chance to assign a node to it, so we must be sure to set these layout attributes
+ *   on our node when one is next assigned to us in @c setNode: . Since there may be cases when we _do_ already
+ *   have our node assigned e.g. during a layout update for existing cells, we also attempt
+ *   to update it now.
+ */
+- (void)applyLayoutAttributes:(UICollectionViewLayoutAttributes *)layoutAttributes
+{
+  self.layoutAttributes = layoutAttributes;
+}
+
+/**
+ * Keep our node filling our content view.
+ */
+- (void)layoutSubviews
+{
+  [super layoutSubviews];
+  self.node.frame = self.contentView.bounds;
+}
+
+@end

AsyncDisplayKit/IGListAdapter+AsyncDisplayKit.h

@@ -0,0 +1,34 @@
+//
+//  IGListAdapter+AsyncDisplayKit.h
+//  AsyncDisplayKit
+//
+//  Created by Adlai Holler on 1/19/17.
+//  Copyright © 2017 Facebook. All rights reserved.
+//
+
+#if IG_LIST_KIT
+
+#import <IGListKit/IGListKit.h>
+
+NS_ASSUME_NONNULL_BEGIN
+
+@class ASCollectionNode;
+
+@interface IGListAdapter (AsyncDisplayKit)
+
+/**
+ * Connect this list adapter to the given collection node.
+ *
+ * @param collectionNode The collection node to drive with this list adapter.
+ *
+ * @note This method may only be called once per list adapter, 
+ *   and it must be called on the main thread. -[UIViewController init]
+ *   is a good place to call it. This method does not retain the collection node.
+ */
+- (void)setASDKCollectionNode:(ASCollectionNode *)collectionNode;
+
+@end
+
+NS_ASSUME_NONNULL_END
+
+#endif // IG_LIST_KIT

AsyncDisplayKit/IGListAdapter+AsyncDisplayKit.m

@@ -0,0 +1,45 @@
+//
+//  IGListAdapter+AsyncDisplayKit.m
+//  AsyncDisplayKit
+//
+//  Created by Adlai Holler on 1/19/17.
+//  Copyright © 2017 Facebook. All rights reserved.
+//
+
+#if IG_LIST_KIT
+
+#import "IGListAdapter+AsyncDisplayKit.h"
+#import "ASIGListAdapterBasedDataSource.h"
+#import "ASAssert.h"
+#import <objc/runtime.h>
+
+@implementation IGListAdapter (AsyncDisplayKit)
+
+- (void)setASDKCollectionNode:(ASCollectionNode *)collectionNode
+{
+  ASDisplayNodeAssertMainThread();
+
+  // Attempt to retrieve previous data source.
+  ASIGListAdapterBasedDataSource *dataSource = objc_getAssociatedObject(self, _cmd);
+  // Bomb if we already made one.
+  if (dataSource != nil) {
+    ASDisplayNodeFailAssert(@"Attempt to call %@ multiple times on the same list adapter. Not currently allowed!", NSStringFromSelector(_cmd));
+    return;
+  }
+
+  // Make a data source and retain it.
+  dataSource = [[ASIGListAdapterBasedDataSource alloc] initWithListAdapter:self];
+  objc_setAssociatedObject(self, _cmd, dataSource, OBJC_ASSOCIATION_RETAIN_NONATOMIC);
+
+  // Attach the data source to the collection node.
+  collectionNode.dataSource = dataSource;
+  collectionNode.delegate = dataSource;
+  __weak IGListAdapter *weakSelf = self;
+  [collectionNode onDidLoad:^(__kindof ASCollectionNode * _Nonnull collectionNode) {
+    weakSelf.collectionView = collectionNode.view;
+  }];
+}
+
+@end
+
+#endif // IG_LIST_KIT

AsyncDisplayKit/Private/ASCollectionInteropProtocols.h

@@ -0,0 +1,34 @@
+//
+//  ASCollectionDataSourceInterop.h
+//  AsyncDisplayKit
+//
+//  Created by Adlai Holler on 1/20/17.
+//  Copyright © 2017 Facebook. All rights reserved.
+//
+
+#import <AsyncDisplayKit/AsyncDisplayKit.h>
+
+NS_ASSUME_NONNULL_BEGIN
+
+/**
+ * Protocols that allow the data source/delegate extra hooks,
+ * to facilitate interop e.g. with IGListKit.
+ */
+
+@protocol ASCollectionDataSourceInterop <ASCollectionDataSource>
+
+- (__kindof UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath;
+
+- (UICollectionReusableView *)collectionView:(UICollectionView *)collectionView viewForSupplementaryElementOfKind:(NSString *)kind atIndexPath:(NSIndexPath *)indexPath;
+
+@end
+
+@protocol ASCollectionDelegateInterop <ASCollectionDelegate>
+
+- (void)collectionView:(UICollectionView *)collectionView willDisplayCell:(UICollectionViewCell *)cell forItemAtIndexPath:(NSIndexPath *)indexPath;
+
+- (void)collectionView:(UICollectionView *)collectionView didEndDisplayingCell:(UICollectionViewCell *)cell forItemAtIndexPath:(NSIndexPath *)indexPath;
+
+@end
+
+NS_ASSUME_NONNULL_END

AsyncDisplayKit/Private/ASDataController+Subclasses.h

@@ -113,6 +113,17 @@ typedef void (^ASDataControllerCompletionBlock)(NSArray<ASCellNode *> *nodes, NS
  */
 - (void)willInsertSections:(NSIndexSet *)sections;
 
+/**
+ * Notifies the subclass to perform setup before sections are deleted in the data controller
+ *
+ * @discussion This method will be performed before the data controller enters its editing queue.
+ * The data source is locked at this point and accessing it is safe. Use this method to set up any nodes or
+ * data stores before entering into editing the backing store on a background thread.
+ *
+ * @param sections Indices of sections to be inserted
+ */
+- (void)prepareForDeleteSections:(NSIndexSet *)sections;
+
 /**
  * Notifies the subclass that the data controller will delete sections at the given positions
  *
@@ -124,18 +135,6 @@ typedef void (^ASDataControllerCompletionBlock)(NSArray<ASCellNode *> *nodes, NS
  */
 - (void)willDeleteSections:(NSIndexSet *)sections;
 
-/**
- * Notifies the subclass that the data controller will move a section to a new position
- *
- * @discussion This method will be performed on the data controller's editing background queue before the parent's
- * concrete implementation. This is a great place to perform any additional transformations like supplementary views
- * or header/footer nodes.
- *
- * @param section    Index of current section position
- * @param newSection Index of new section position
- */
-- (void)willMoveSection:(NSInteger)section toSection:(NSInteger)newSection;
-
 /**
  * Notifies the subclass to perform setup before rows are inserted in the data controller.
  *

AsyncDisplayKit/Private/ASIGListAdapterBasedDataSource.h

@@ -0,0 +1,22 @@
+//
+//  ASIGListAdapterBasedDataSource.h
+//  AsyncDisplayKit
+//
+//  Created by Adlai Holler on 1/19/17.
+//  Copyright © 2017 Facebook. All rights reserved.
+//
+
+#if IG_LIST_KIT
+
+#import <IGListKit/IGListKit.h>
+#import <AsyncDisplayKit/AsyncDisplayKit.h>
+#import "ASCollectionInteropProtocols.h"
+
+AS_SUBCLASSING_RESTRICTED
+@interface ASIGListAdapterBasedDataSource : NSObject <ASCollectionDataSourceInterop, ASCollectionDelegateInterop, ASCollectionDelegateFlowLayout>
+
+- (instancetype)initWithListAdapter:(IGListAdapter *)listAdapter;
+
+@end
+
+#endif

AsyncDisplayKit/Private/ASIGListAdapterBasedDataSource.m

@@ -0,0 +1,315 @@
+//
+//  ASIGListAdapterBasedDataSource.m
+//  AsyncDisplayKit
+//
+//  Created by Adlai Holler on 1/19/17.
+//  Copyright © 2017 Facebook. All rights reserved.
+//
+
+#if IG_LIST_KIT
+
+#import "ASIGListAdapterBasedDataSource.h"
+#import <AsyncDisplayKit/AsyncDisplayKit.h>
+#import <objc/runtime.h>
+
+typedef IGListSectionController<IGListSectionType, ASSectionController> ASIGSectionController;
+
+/// The optional methods that a class implements from ASSectionController.
+/// Note: Bitfields are not supported by NSValue so we can't use them.
+typedef struct {
+  BOOL sizeRangeForItem;
+  BOOL shouldBatchFetch;
+  BOOL beginBatchFetchWithContext;
+} ASSectionControllerOverrides;
+
+/// The optional methods that a class implements from ASSupplementaryNodeSource.
+/// Note: Bitfields are not supported by NSValue so we can't use them.
+typedef struct {
+  BOOL sizeRangeForSupplementary;
+} ASSupplementarySourceOverrides;
+
+@protocol ASIGSupplementaryNodeSource <IGListSupplementaryViewSource, ASSupplementaryNodeSource>
+@end
+
+@interface ASIGListAdapterBasedDataSource ()
+@property (nonatomic, weak, readonly) IGListAdapter *listAdapter;
+@property (nonatomic, readonly) id<UICollectionViewDelegateFlowLayout> delegate;
+@property (nonatomic, readonly) id<UICollectionViewDataSource> dataSource;
+
+/**
+ * The section controller that we will forward beginBatchFetchWithContext: to.
+ * Since shouldBatchFetch: is called on main, we capture the last section controller in there,
+ * and then we use it and clear it in beginBatchFetchWithContext: (on default queue).
+ *
+ * It is safe to use it without a lock in this limited way, since those two methods will
+ * never execute in parallel.6
+ */
+@property (nonatomic, weak) ASIGSectionController *sectionControllerForBatchFetching;
+@end
+
+@implementation ASIGListAdapterBasedDataSource
+
+- (instancetype)initWithListAdapter:(IGListAdapter *)listAdapter
+{
+  if (self = [super init]) {
+    [ASIGListAdapterBasedDataSource setASCollectionViewSuperclass];
+    [ASIGListAdapterBasedDataSource configureUpdater:listAdapter.updater];
+
+    ASDisplayNodeAssert([listAdapter conformsToProtocol:@protocol(UICollectionViewDataSource)], @"Expected IGListAdapter to conform to UICollectionViewDataSource.");
+    ASDisplayNodeAssert([listAdapter conformsToProtocol:@protocol(UICollectionViewDelegateFlowLayout)], @"Expected IGListAdapter to conform to UICollectionViewDelegateFlowLayout.");
+    _listAdapter = listAdapter;
+  }
+  return self;
+}
+
+- (id<UICollectionViewDataSource>)dataSource
+{
+  return (id<UICollectionViewDataSource>)_listAdapter;
+}
+
+- (id<UICollectionViewDelegateFlowLayout>)delegate
+{
+  return (id<UICollectionViewDelegateFlowLayout>)_listAdapter;
+}
+
+#pragma mark - ASCollectionDelegate
+
+- (void)collectionNode:(ASCollectionNode *)collectionNode didSelectItemAtIndexPath:(NSIndexPath *)indexPath
+{
+  [self.delegate collectionView:collectionNode.view didSelectItemAtIndexPath:indexPath];
+}
+
+- (void)scrollViewDidScroll:(UIScrollView *)scrollView
+{
+  [self.delegate scrollViewDidScroll:scrollView];
+}
+
+- (void)scrollViewWillBeginDragging:(UIScrollView *)scrollView
+{
+  [self.delegate scrollViewWillBeginDragging:scrollView];
+}
+
+- (void)scrollViewDidEndDragging:(UIScrollView *)scrollView willDecelerate:(BOOL)decelerate
+{
+  [self.delegate scrollViewDidEndDragging:scrollView willDecelerate:decelerate];
+}
+
+- (BOOL)shouldBatchFetchForCollectionNode:(ASCollectionNode *)collectionNode
+{
+  NSInteger sectionCount = [self numberOfSectionsInCollectionNode:collectionNode];
+  if (sectionCount == 0) {
+    return NO;
+  }
+
+  // If they implement shouldBatchFetch, call it. Otherwise, just say YES if they implement beginBatchFetch.
+  ASIGSectionController *ctrl = [self sectionControllerForSection:sectionCount - 1];
+  ASSectionControllerOverrides o = [ASIGListAdapterBasedDataSource overridesForSectionControllerClass:ctrl.class];
+  BOOL result = (o.shouldBatchFetch ? [ctrl shouldBatchFetch] : o.beginBatchFetchWithContext);
+  if (result) {
+    self.sectionControllerForBatchFetching = ctrl;
+  }
+  return result;
+}
+
+- (void)collectionNode:(ASCollectionNode *)collectionNode willBeginBatchFetchWithContext:(ASBatchContext *)context
+{
+  ASIGSectionController *ctrl = self.sectionControllerForBatchFetching;
+  self.sectionControllerForBatchFetching = nil;
+  [ctrl beginBatchFetchWithContext:context];
+}
+
+/**
+ * Note: It is not documented that ASCollectionNode will forward these UIKit delegate calls if they are implemented.
+ * It is not considered harmful to do so, and adding them to documentation will confuse most users, who should
+ * instead using the ASCollectionDelegate callbacks.
+ */
+#pragma mark - ASCollectionDelegateInterop
+
+- (void)collectionView:(UICollectionView *)collectionView willDisplayCell:(UICollectionViewCell *)cell forItemAtIndexPath:(NSIndexPath *)indexPath
+{
+  [self.delegate collectionView:collectionView willDisplayCell:cell forItemAtIndexPath:indexPath];
+}
+
+- (void)collectionView:(UICollectionView *)collectionView didEndDisplayingCell:(UICollectionViewCell *)cell forItemAtIndexPath:(NSIndexPath *)indexPath
+{
+  [self.delegate collectionView:collectionView didEndDisplayingCell:cell forItemAtIndexPath:indexPath];
+}
+
+#pragma mark - ASCollectionDelegateFlowLayout
+
+- (ASSizeRange)collectionNode:(ASCollectionNode *)collectionNode sizeRangeForHeaderInSection:(NSInteger)section
+{
+  id<ASIGSupplementaryNodeSource> src = [self supplementaryElementSourceForSection:section];
+  if ([ASIGListAdapterBasedDataSource overridesForSupplementarySourceClass:[src class]].sizeRangeForSupplementary) {
+    return [src sizeRangeForSupplementaryElementOfKind:UICollectionElementKindSectionHeader atIndex:0];
+  } else {
+    return ASSizeRangeZero;
+  }
+}
+
+- (ASSizeRange)collectionNode:(ASCollectionNode *)collectionNode sizeRangeForFooterInSection:(NSInteger)section
+{
+  id<ASIGSupplementaryNodeSource> src = [self supplementaryElementSourceForSection:section];
+  if ([ASIGListAdapterBasedDataSource overridesForSupplementarySourceClass:[src class]].sizeRangeForSupplementary) {
+    return [src sizeRangeForSupplementaryElementOfKind:UICollectionElementKindSectionFooter atIndex:0];
+  } else {
+    return ASSizeRangeZero;
+  }
+}
+
+- (UIEdgeInsets)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout *)collectionViewLayout insetForSectionAtIndex:(NSInteger)section
+{
+  return [self.delegate collectionView:collectionView layout:collectionViewLayout insetForSectionAtIndex:section];
+}
+
+- (CGFloat)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout *)collectionViewLayout minimumLineSpacingForSectionAtIndex:(NSInteger)section
+{
+  return [self.delegate collectionView:collectionView layout:collectionViewLayout minimumLineSpacingForSectionAtIndex:section];
+}
+
+- (CGFloat)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout *)collectionViewLayout minimumInteritemSpacingForSectionAtIndex:(NSInteger)section
+{
+  return [self.delegate collectionView:collectionView layout:collectionViewLayout minimumInteritemSpacingForSectionAtIndex:section];
+}
+
+#pragma mark - ASCollectionDataSource
+
+- (NSInteger)collectionNode:(ASCollectionNode *)collectionNode numberOfItemsInSection:(NSInteger)section
+{
+  return [self.dataSource collectionView:collectionNode.view numberOfItemsInSection:section];
+}
+
+- (NSInteger)numberOfSectionsInCollectionNode:(ASCollectionNode *)collectionNode
+{
+  return [self.dataSource numberOfSectionsInCollectionView:collectionNode.view];
+}
+
+- (ASCellNodeBlock)collectionNode:(ASCollectionNode *)collectionNode nodeBlockForItemAtIndexPath:(NSIndexPath *)indexPath
+{
+  return [[self sectionControllerForSection:indexPath.section] nodeBlockForItemAtIndex:indexPath.item];
+}
+
+- (ASSizeRange)collectionNode:(ASCollectionNode *)collectionNode constrainedSizeForItemAtIndexPath:(NSIndexPath *)indexPath
+{
+  ASIGSectionController *ctrl = [self sectionControllerForSection:indexPath.section];
+  if ([ASIGListAdapterBasedDataSource overridesForSectionControllerClass:ctrl.class].sizeRangeForItem) {
+    return [ctrl sizeRangeForItemAtIndex:indexPath.item];
+  } else {
+    return ASSizeRangeUnconstrained;
+  }
+}
+
+- (ASCellNode *)collectionNode:(ASCollectionNode *)collectionNode nodeForSupplementaryElementOfKind:(NSString *)kind atIndexPath:(NSIndexPath *)indexPath
+{
+  return [[self supplementaryElementSourceForSection:indexPath.section] nodeForSupplementaryElementOfKind:kind atIndex:indexPath.item];
+}
+
+- (NSArray<NSString *> *)collectionNode:(ASCollectionNode *)collectionNode supplementaryElementKindsInSection:(NSInteger)section
+{
+  return [[self supplementaryElementSourceForSection:section] supportedElementKinds];
+}
+
+#pragma mark - ASCollectionDataSourceInterop
+
+- (__kindof UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(nonnull NSIndexPath *)indexPath
+{
+  return [self.dataSource collectionView:collectionView cellForItemAtIndexPath:indexPath];
+}
+
+- (UICollectionReusableView *)collectionView:(UICollectionView *)collectionView viewForSupplementaryElementOfKind:(NSString *)kind atIndexPath:(NSIndexPath *)indexPath
+{
+  return [self.dataSource collectionView:collectionView viewForSupplementaryElementOfKind:kind atIndexPath:indexPath];
+}
+
+#pragma mark - Helpers
+
+- (id<ASIGSupplementaryNodeSource>)supplementaryElementSourceForSection:(NSInteger)section
+{
+  ASIGSectionController *ctrl = [self sectionControllerForSection:section];
+  id<ASIGSupplementaryNodeSource> src = (id<ASIGSupplementaryNodeSource>)ctrl.supplementaryViewSource;
+  ASDisplayNodeAssert(src == nil || [src conformsToProtocol:@protocol(ASSupplementaryNodeSource)], @"Supplementary view source should conform to %@", NSStringFromProtocol(@protocol(ASSupplementaryNodeSource)));
+  return src;
+}
+
+- (ASIGSectionController *)sectionControllerForSection:(NSInteger)section
+{
+  id object = [_listAdapter objectAtSection:section];
+  ASIGSectionController *ctrl = (ASIGSectionController *)[_listAdapter sectionControllerForObject:object];
+  ASDisplayNodeAssert([ctrl conformsToProtocol:@protocol(ASSectionController)], @"Expected section controller to conform to %@. Controller: %@", NSStringFromProtocol(@protocol(ASSectionController)), ctrl);
+  return ctrl;
+}
+
+/**
+ * Set ASCollectionView's superclass to IGListCollectionView.
+ * Scary! If IGListKit removed the subclassing restriction, we could
+ * use #if in the @interface to choose the superclass based on
+ * whether we have IGListKit available.
+ */
++ (void)setASCollectionViewSuperclass
+{
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wdeprecated-declarations"
+  static dispatch_once_t onceToken;
+  dispatch_once(&onceToken, ^{
+    class_setSuperclass([ASCollectionView class], [IGListCollectionView class]);
+  });
+#pragma clang diagnostic pop
+}
+
+/// Ensure updater won't call reloadData on us.
++ (void)configureUpdater:(id<IGListUpdatingDelegate>)updater
+{
+  // Cast to NSObject will be removed after https://github.com/Instagram/IGListKit/pull/435
+  if ([(id<NSObject>)updater isKindOfClass:[IGListAdapterUpdater class]]) {
+    [(IGListAdapterUpdater *)updater setAllowsBackgroundReloading:NO];
+  } else {
+    static dispatch_once_t onceToken;
+    dispatch_once(&onceToken, ^{
+      NSLog(@"WARNING: Use of non-%@ updater with AsyncDisplayKit is discouraged. Updater: %@", NSStringFromClass([IGListAdapterUpdater class]), updater);
+    });
+  }
+}
+
++ (ASSupplementarySourceOverrides)overridesForSupplementarySourceClass:(Class)c
+{
+  static NSCache<Class, NSValue *> *cache;
+  static dispatch_once_t onceToken;
+  dispatch_once(&onceToken, ^{
+    cache = [[NSCache alloc] init];
+  });
+  NSValue *obj = [cache objectForKey:c];
+  ASSupplementarySourceOverrides o;
+  if (obj == nil) {
+    o.sizeRangeForSupplementary = [c instancesRespondToSelector:@selector(sizeRangeForSupplementaryElementOfKind:atIndex:)];
+    obj = [NSValue valueWithBytes:&o objCType:@encode(ASSupplementarySourceOverrides)];
+    [cache setObject:obj forKey:c];
+  } else {
+    [obj getValue:&o];
+  }
+  return o;
+}
+
++ (ASSectionControllerOverrides)overridesForSectionControllerClass:(Class)c
+{
+  static NSCache<Class, NSValue *> *cache;
+  static dispatch_once_t onceToken;
+  dispatch_once(&onceToken, ^{
+    cache = [[NSCache alloc] init];
+  });
+  NSValue *obj = [cache objectForKey:c];
+  ASSectionControllerOverrides o;
+  if (obj == nil) {
+    o.sizeRangeForItem = [c instancesRespondToSelector:@selector(sizeRangeForItemAtIndex:)];
+    o.beginBatchFetchWithContext = [c instancesRespondToSelector:@selector(beginBatchFetchWithContext:)];
+    o.shouldBatchFetch = [c instancesRespondToSelector:@selector(shouldBatchFetch)];
+    obj = [NSValue valueWithBytes:&o objCType:@encode(ASSectionControllerOverrides)];
+    [cache setObject:obj forKey:c];
+  } else {
+    [obj getValue:&o];
+  }
+  return o;
+}
+
+@end
+
+#endif // IG_LIST_KIT

AsyncDisplayKitTests/ASCollectionViewTests.mm

@@ -164,7 +164,7 @@
 
 @interface ASCollectionView (InternalTesting)
 
-- (NSArray *)supplementaryNodeKindsInDataController:(ASCollectionDataController *)dataController;
+- (NSArray *)supplementaryNodeKindsInDataController:(ASCollectionDataController *)dataController sections:(nonnull NSIndexSet *)sections;
 
 @end
 
@@ -219,7 +219,7 @@
   UICollectionViewFlowLayout *layout = [[UICollectionViewFlowLayout alloc] init];
   ASCollectionView *collectionView = [[ASCollectionView alloc] initWithFrame:CGRectZero collectionViewLayout:layout];
   [collectionView registerSupplementaryNodeOfKind:UICollectionElementKindSectionHeader];
-  XCTAssertEqualObjects([collectionView supplementaryNodeKindsInDataController:nil], @[UICollectionElementKindSectionHeader]);
+  XCTAssertEqualObjects([collectionView supplementaryNodeKindsInDataController:nil sections:[NSIndexSet indexSetWithIndex:0]], @[UICollectionElementKindSectionHeader]);
 }
 
 - (void)testReloadIfNeeded

AsyncDisplayKitTests/ASDisplayNodeTests.m

@@ -2144,11 +2144,16 @@ static bool stringContainsPointer(NSString *description, id p) {
   XCTAssertNoThrow([node.view layoutIfNeeded]);
 }
 
-- (void)testThatOnDidLoadThrowsIfCalledOnLoaded
+- (void)testThatOnDidLoadThrowsIfCalledOnLoadedOffMain
 {
   ASTestDisplayNode *node = [[ASTestDisplayNode alloc] init];
   [node view];
-  XCTAssertThrows([node onDidLoad:^(ASDisplayNode * _Nonnull node) { }]);
+  dispatch_semaphore_t sem = dispatch_semaphore_create(0);
+  [NSThread detachNewThreadWithBlock:^{
+    XCTAssertThrows([node onDidLoad:^(ASDisplayNode * _Nonnull node) { }]);
+    dispatch_semaphore_signal(sem);
+  }];
+  dispatch_semaphore_wait(sem, DISPATCH_TIME_FOREVER);
 }
 
 - (void)testThatOnDidLoadWorks

build.sh

@@ -30,7 +30,20 @@ if [ "$MODE" = "tests" ]; then
         -scheme AsyncDisplayKit \
         -sdk "$SDK" \
         -destination "$PLATFORM" \
-        build test | xcpretty $FORMATTER
+        build-for-testing test | xcpretty $FORMATTER
+    trap - EXIT
+    exit 0
+fi
+
+if [ "$MODE" = "tests_listkit" ]; then
+    echo "Building & testing AsyncDisplayKit+IGListKit."
+    pod install --project-directory=ASDKListKit
+    set -o pipefail && xcodebuild \
+        -workspace ASDKListKit/ASDKListKit.xcworkspace \
+        -scheme ASDKListKitTests \
+        -sdk "$SDK" \
+        -destination "$PLATFORM" \
+        build-for-testing test | xcpretty $FORMATTER
     trap - EXIT
     exit 0
 fi

examples/ASCollectionView/Sample/ViewController.m

@@ -21,7 +21,7 @@
 #import "SupplementaryNode.h"
 #import "ItemNode.h"
 
-@interface ViewController () <ASCollectionDataSource, ASCollectionViewDelegateFlowLayout>
+@interface ViewController () <ASCollectionDataSource, ASCollectionDelegateFlowLayout>
 
 @property (nonatomic, strong) ASCollectionNode *collectionNode;
 @property (nonatomic, strong) NSArray *data;

examples/ASDKgram/Podfile

@@ -1,6 +1,7 @@
 source 'https://github.com/CocoaPods/Specs.git'
-platform :ios, '7.0'
+platform :ios, '8.0'
 target 'Sample' do
-	pod 'AsyncDisplayKit', :path => '../..'
+	pod 'AsyncDisplayKit/IGListKit', :path => '../..'
+	pod 'AsyncDisplayKit/PINRemoteImage', :path => '../..'
 end
 

examples/ASDKgram/Sample.xcodeproj/project.pbxproj

@@ -31,6 +31,11 @@
 		768843931CAA37EF00D8629E /* UserModel.m in Sources */ = {isa = PBXBuildFile; fileRef = 7688437B1CAA37EF00D8629E /* UserModel.m */; };
 		768843961CAA37EF00D8629E /* Utilities.m in Sources */ = {isa = PBXBuildFile; fileRef = 7688437E1CAA37EF00D8629E /* Utilities.m */; };
 		B13424EE6D36C2EC5D1030B6 /* libPods-Sample.a in Frameworks */ = {isa = PBXBuildFile; fileRef = AD5DDA0A29B0F32AA5CC47BA /* libPods-Sample.a */; };
+		CC00D1571E15912F004E5502 /* PhotoFeedListKitViewController.m in Sources */ = {isa = PBXBuildFile; fileRef = CC00D1561E15912F004E5502 /* PhotoFeedListKitViewController.m */; };
+		CC5369AC1E15925200FAD348 /* PhotoFeedSectionController.m in Sources */ = {isa = PBXBuildFile; fileRef = CC5369AB1E15925200FAD348 /* PhotoFeedSectionController.m */; };
+		CC5532171E15CC1E0011C01F /* ASCollectionSectionController.m in Sources */ = {isa = PBXBuildFile; fileRef = CC5532161E15CC1E0011C01F /* ASCollectionSectionController.m */; };
+		CC6350BB1E1C482D002BC613 /* TailLoadingNode.m in Sources */ = {isa = PBXBuildFile; fileRef = CC6350BA1E1C482D002BC613 /* TailLoadingNode.m */; };
+		CC85250F1E36B392008EABE6 /* FeedHeaderNode.m in Sources */ = {isa = PBXBuildFile; fileRef = CC85250E1E36B392008EABE6 /* FeedHeaderNode.m */; };
 /* End PBXBuildFile section */
 
 /* Begin PBXFileReference section */
@@ -80,6 +85,17 @@
 		7688437F1CAA37EF00D8629E /* Info.plist */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = text.plist.xml; path = Info.plist; sourceTree = "<group>"; };
 		97A9B1BAF4265967672F9EA3 /* Pods-Sample.debug.xcconfig */ = {isa = PBXFileReference; includeInIndex = 1; lastKnownFileType = text.xcconfig; name = "Pods-Sample.debug.xcconfig"; path = "Pods/Target Support Files/Pods-Sample/Pods-Sample.debug.xcconfig"; sourceTree = "<group>"; };
 		AD5DDA0A29B0F32AA5CC47BA /* libPods-Sample.a */ = {isa = PBXFileReference; explicitFileType = archive.ar; includeInIndex = 0; path = "libPods-Sample.a"; sourceTree = BUILT_PRODUCTS_DIR; };
+		CC00D1551E15912F004E5502 /* PhotoFeedListKitViewController.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = PhotoFeedListKitViewController.h; sourceTree = "<group>"; };
+		CC00D1561E15912F004E5502 /* PhotoFeedListKitViewController.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = PhotoFeedListKitViewController.m; sourceTree = "<group>"; };
+		CC5369AA1E15925200FAD348 /* PhotoFeedSectionController.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = PhotoFeedSectionController.h; sourceTree = "<group>"; };
+		CC5369AB1E15925200FAD348 /* PhotoFeedSectionController.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = PhotoFeedSectionController.m; sourceTree = "<group>"; };
+		CC5532111E159D770011C01F /* RefreshingSectionControllerType.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = RefreshingSectionControllerType.h; sourceTree = "<group>"; };
+		CC5532151E15CC1E0011C01F /* ASCollectionSectionController.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = ASCollectionSectionController.h; sourceTree = "<group>"; };
+		CC5532161E15CC1E0011C01F /* ASCollectionSectionController.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = ASCollectionSectionController.m; sourceTree = "<group>"; };
+		CC6350B91E1C482D002BC613 /* TailLoadingNode.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = TailLoadingNode.h; sourceTree = "<group>"; };
+		CC6350BA1E1C482D002BC613 /* TailLoadingNode.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = TailLoadingNode.m; sourceTree = "<group>"; };
+		CC85250D1E36B392008EABE6 /* FeedHeaderNode.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = FeedHeaderNode.h; sourceTree = "<group>"; };
+		CC85250E1E36B392008EABE6 /* FeedHeaderNode.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = FeedHeaderNode.m; sourceTree = "<group>"; };
 		D09B5DF0BFB37583DE8F3142 /* Pods-Sample.release.xcconfig */ = {isa = PBXFileReference; includeInIndex = 1; lastKnownFileType = text.xcconfig; name = "Pods-Sample.release.xcconfig"; path = "Pods/Target Support Files/Pods-Sample/Pods-Sample.release.xcconfig"; sourceTree = "<group>"; };
 /* End PBXFileReference section */
 
@@ -169,6 +185,7 @@
 			children = (
 				767A5F161CAA3D96004CDA8D /* UIKit */,
 				767A5F151CAA3D90004CDA8D /* ASDK */,
+				CC00D1581E159132004E5502 /* ASDK-ListKit */,
 			);
 			name = Controller;
 			sourceTree = "<group>";
@@ -239,6 +256,10 @@
 		767A5F1A1CAA3DBF004CDA8D /* ASDK */ = {
 			isa = PBXGroup;
 			children = (
+				CC85250D1E36B392008EABE6 /* FeedHeaderNode.h */,
+				CC85250E1E36B392008EABE6 /* FeedHeaderNode.m */,
+				CC6350B91E1C482D002BC613 /* TailLoadingNode.h */,
+				CC6350BA1E1C482D002BC613 /* TailLoadingNode.m */,
 				7688435B1CAA37EF00D8629E /* PhotoCellNode.h */,
 				768843731CAA37EF00D8629E /* PhotoCellNode.m */,
 				768843541CAA37EF00D8629E /* CommentsNode.h */,
@@ -247,6 +268,20 @@
 			name = ASDK;
 			sourceTree = "<group>";
 		};
+		CC00D1581E159132004E5502 /* ASDK-ListKit */ = {
+			isa = PBXGroup;
+			children = (
+				CC5532111E159D770011C01F /* RefreshingSectionControllerType.h */,
+				CC00D1551E15912F004E5502 /* PhotoFeedListKitViewController.h */,
+				CC00D1561E15912F004E5502 /* PhotoFeedListKitViewController.m */,
+				CC5369AA1E15925200FAD348 /* PhotoFeedSectionController.h */,
+				CC5369AB1E15925200FAD348 /* PhotoFeedSectionController.m */,
+				CC5532151E15CC1E0011C01F /* ASCollectionSectionController.h */,
+				CC5532161E15CC1E0011C01F /* ASCollectionSectionController.m */,
+			);
+			name = "ASDK-ListKit";
+			sourceTree = "<group>";
+		};
 /* End PBXGroup section */
 
 /* Begin PBXNativeTarget section */
@@ -378,15 +413,20 @@
 				768843831CAA37EF00D8629E /* CommentsNode.m in Sources */,
 				768843961CAA37EF00D8629E /* Utilities.m in Sources */,
 				768843931CAA37EF00D8629E /* UserModel.m in Sources */,
+				CC5532171E15CC1E0011C01F /* ASCollectionSectionController.m in Sources */,
 				768843801CAA37EF00D8629E /* AppDelegate.m in Sources */,
 				768843811CAA37EF00D8629E /* CommentFeedModel.m in Sources */,
 				7688438E1CAA37EF00D8629E /* PhotoFeedNodeController.m in Sources */,
+				CC6350BB1E1C482D002BC613 /* TailLoadingNode.m in Sources */,
+				CC85250F1E36B392008EABE6 /* FeedHeaderNode.m in Sources */,
 				768843841CAA37EF00D8629E /* CommentView.m in Sources */,
 				768843881CAA37EF00D8629E /* LocationModel.m in Sources */,
 				768843901CAA37EF00D8629E /* PhotoModel.m in Sources */,
 				768843911CAA37EF00D8629E /* PhotoTableViewCell.m in Sources */,
+				CC00D1571E15912F004E5502 /* PhotoFeedListKitViewController.m in Sources */,
 				7688438B1CAA37EF00D8629E /* PhotoCellNode.m in Sources */,
 				7688438D1CAA37EF00D8629E /* PhotoFeedModel.m in Sources */,
+				CC5369AC1E15925200FAD348 /* PhotoFeedSectionController.m in Sources */,
 				768843851CAA37EF00D8629E /* ImageURLModel.m in Sources */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;

examples/ASDKgram/Sample.xcworkspace/contents.xcworkspacedata

@@ -0,0 +1,10 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<Workspace
+   version = "1.0">
+   <FileRef
+      location = "group:Sample.xcodeproj">
+   </FileRef>
+   <FileRef
+      location = "group:Pods/Pods.xcodeproj">
+   </FileRef>
+</Workspace>

examples/ASDKgram/Sample/ASCollectionSectionController.h

@@ -0,0 +1,28 @@
+//
+//  ASCollectionSectionController.h
+//  Sample
+//
+//  Created by Adlai Holler on 12/29/16.
+//  Copyright © 2016 Facebook. All rights reserved.
+//
+
+#import <IGListKit/IGListKit.h>
+
+NS_ASSUME_NONNULL_BEGIN
+
+@interface ASCollectionSectionController : IGListSectionController
+
+/**
+ * The items managed by this section controller.
+ */
+@property (nonatomic, strong, readonly) NSArray<id<IGListDiffable>> *items;
+
+- (void)setItems:(NSArray<id<IGListDiffable>> *)newItems
+        animated:(BOOL)animated
+      completion:(nullable void(^)())completion;
+
+- (NSInteger)numberOfItems;
+
+@end
+
+NS_ASSUME_NONNULL_END

examples/ASDKgram/Sample/ASCollectionSectionController.m

@@ -0,0 +1,79 @@
+//
+//  ASCollectionSectionController.m
+//  Sample
+//
+//  Created by Adlai Holler on 12/29/16.
+//  Copyright © 2016 Facebook. All rights reserved.
+//
+
+#import "ASCollectionSectionController.h"
+#import <AsyncDisplayKit/AsyncDisplayKit.h>
+
+@interface ASCollectionSectionController ()
+@property (nonatomic, strong, readonly) dispatch_queue_t diffingQueue;
+
+/// The items that have been diffed and are waiting to be submitted to the collection view.
+/// Should always be accessed on the diffing queue, and should never be accessed
+/// before the initial items are read (in -numberOfItems).
+@property (nonatomic, copy) NSArray *pendingItems;
+
+@property (nonatomic) BOOL initialItemsRead;
+@end
+
+@implementation ASCollectionSectionController
+@synthesize diffingQueue = _diffingQueue;
+
+- (NSInteger)numberOfItems
+{
+  if (_initialItemsRead == NO) {
+    _pendingItems = self.items;
+    _initialItemsRead = YES;
+  }
+  return self.items.count;
+}
+
+- (dispatch_queue_t)diffingQueue
+{
+  if (_diffingQueue == nil) {
+    _diffingQueue = dispatch_queue_create("ASCollectionSectionController.diffingQueue", DISPATCH_QUEUE_SERIAL);
+  }
+  return _diffingQueue;
+}
+
+- (void)setItems:(NSArray *)newItems animated:(BOOL)animated completion:(void(^)())completion
+{
+  ASDisplayNodeAssertMainThread();
+  newItems = [newItems copy];
+  if (!self.initialItemsRead) {
+    _items = newItems;
+    if (completion) {
+      completion();
+    }
+    return;
+  }
+
+  BOOL wasEmpty = (self.items.count == 0);
+
+  dispatch_async(self.diffingQueue, ^{
+    IGListIndexSetResult *result = IGListDiff(self.pendingItems, newItems, IGListDiffPointerPersonality);
+    self.pendingItems = newItems;
+    dispatch_async(dispatch_get_main_queue(), ^{
+      id<IGListCollectionContext> ctx = self.collectionContext;
+      [ctx performBatchAnimated:animated updates:^{
+        [ctx insertInSectionController:(id)self atIndexes:result.inserts];
+        [ctx deleteInSectionController:(id)self atIndexes:result.deletes];
+        _items = newItems;
+      } completion:^(BOOL finished) {
+        if (completion) {
+          completion();
+        }
+        // WORKAROUND for https://github.com/Instagram/IGListKit/issues/378
+        if (wasEmpty) {
+          [(IGListAdapter *)ctx performUpdatesAnimated:NO completion:nil];
+        }
+      }];
+    });
+  });
+}
+
+@end

examples/ASDKgram/Sample/AppDelegate.m

@@ -20,6 +20,7 @@
 #import "AppDelegate.h"
 #import "PhotoFeedViewController.h"
 #import "PhotoFeedNodeController.h"
+#import "PhotoFeedListKitViewController.h"
 #import "WindowWithStatusBarUnderlay.h"
 #import "Utilities.h"
 
@@ -37,13 +38,19 @@
   _window                  = [[WindowWithStatusBarUnderlay alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
   _window.backgroundColor  = [UIColor whiteColor];
   
-  // UIKit Home Feed viewController & navController
+  // ASDK Home Feed viewController & navController
   PhotoFeedNodeController *asdkHomeFeedVC      = [[PhotoFeedNodeController alloc] init];
   UINavigationController *asdkHomeFeedNavCtrl  = [[UINavigationController alloc] initWithRootViewController:asdkHomeFeedVC];
   asdkHomeFeedNavCtrl.tabBarItem               = [[UITabBarItem alloc] initWithTitle:@"ASDK" image:[UIImage imageNamed:@"home"] tag:0];
   asdkHomeFeedNavCtrl.hidesBarsOnSwipe         = YES;
-  
+
-  // ASDK Home Feed viewController & navController
+  // ListKit Home Feed viewController & navController
+  PhotoFeedListKitViewController *listKitHomeFeedVC      = [[PhotoFeedListKitViewController alloc] init];
+  UINavigationController *listKitHomeFeedNavCtrl  = [[UINavigationController alloc] initWithRootViewController:listKitHomeFeedVC];
+  listKitHomeFeedNavCtrl.tabBarItem               = [[UITabBarItem alloc] initWithTitle:@"ListKit" image:[UIImage imageNamed:@"home"] tag:0];
+  listKitHomeFeedNavCtrl.hidesBarsOnSwipe         = YES;
+
+  // UIKit Home Feed viewController & navController
   PhotoFeedViewController *uikitHomeFeedVC     = [[PhotoFeedViewController alloc] init];
   UINavigationController *uikitHomeFeedNavCtrl = [[UINavigationController alloc] initWithRootViewController:uikitHomeFeedVC];
   uikitHomeFeedNavCtrl.tabBarItem              = [[UITabBarItem alloc] initWithTitle:@"UIKit" image:[UIImage imageNamed:@"home"] tag:0];
@@ -51,7 +58,7 @@
 
   // UITabBarController
   UITabBarController *tabBarController         = [[UITabBarController alloc] init];
-  tabBarController.viewControllers             = @[uikitHomeFeedNavCtrl, asdkHomeFeedNavCtrl];
+  tabBarController.viewControllers             = @[uikitHomeFeedNavCtrl, asdkHomeFeedNavCtrl, listKitHomeFeedNavCtrl];
   tabBarController.selectedViewController      = asdkHomeFeedNavCtrl;
   tabBarController.delegate                    = self;
   [[UITabBar appearance] setTintColor:[UIColor darkBlueColor]];

examples/ASDKgram/Sample/FeedHeaderNode.h

@@ -0,0 +1,13 @@
+//
+//  FeedHeaderNode.h
+//  Sample
+//
+//  Created by Adlai Holler on 1/23/17.
+//  Copyright © 2017 Facebook. All rights reserved.
+//
+
+#import <AsyncDisplayKit/AsyncDisplayKit.h>
+
+@interface FeedHeaderNode : ASCellNode
+
+@end

examples/ASDKgram/Sample/FeedHeaderNode.m

@@ -0,0 +1,35 @@
+//
+//  FeedHeaderNode.m
+//  Sample
+//
+//  Created by Adlai Holler on 1/23/17.
+//  Copyright © 2017 Facebook. All rights reserved.
+//
+
+#import "FeedHeaderNode.h"
+#import "Utilities.h"
+
+static UIEdgeInsets kFeedHeaderInset = { .top = 20, .bottom = 20, .left = 10, .right = 10 };
+
+@interface FeedHeaderNode ()
+@property (nonatomic, strong, readonly) ASTextNode *textNode;
+@end
+
+@implementation FeedHeaderNode
+
+- (instancetype)init
+{
+  if (self = [super init]) {
+    _textNode = [[ASTextNode alloc] init];
+    self.automaticallyManagesSubnodes = YES;
+    _textNode.attributedText = [NSAttributedString attributedStringWithString:@"Latest Posts" fontSize:18 color:[UIColor darkGrayColor] firstWordColor:nil];
+  }
+  return self;
+}
+
+- (ASLayoutSpec *)layoutSpecThatFits:(ASSizeRange)constrainedSize
+{
+  return [ASInsetLayoutSpec insetLayoutSpecWithInsets:kFeedHeaderInset child:_textNode];
+}
+
+@end

examples/ASDKgram/Sample/PhotoFeedListKitViewController.h

@@ -0,0 +1,14 @@
+//
+//  PhotoFeedListKitViewController.h
+//  Sample
+//
+//  Created by Adlai Holler on 12/29/16.
+//  Copyright © 2016 Facebook. All rights reserved.
+//
+
+#import <AsyncDisplayKit/AsyncDisplayKit.h>
+#import "AppDelegate.h"
+
+@interface PhotoFeedListKitViewController<ASCollectionNode> : ASViewController <PhotoFeedControllerProtocol>
+
+@end

examples/ASDKgram/Sample/PhotoFeedListKitViewController.m

@@ -0,0 +1,106 @@
+//
+//  PhotoFeedListKitViewController.m
+//  Sample
+//
+//  Created by Adlai Holler on 12/29/16.
+//  Copyright © 2016 Facebook. All rights reserved.
+//
+
+#import "PhotoFeedListKitViewController.h"
+#import <IGListKit/IGListKit.h>
+#import "PhotoFeedModel.h"
+#import "PhotoFeedSectionController.h"
+#import "RefreshingSectionControllerType.h"
+
+@interface PhotoFeedListKitViewController () <IGListAdapterDataSource, ASCollectionDelegate>
+@property (nonatomic, strong) IGListAdapter *listAdapter;
+@property (nonatomic, strong) PhotoFeedModel *photoFeed;
+@property (nonatomic, strong, readonly) ASCollectionNode *collectionNode;
+@property (nonatomic, strong, readonly) UIActivityIndicatorView *spinner;
+@property (nonatomic, strong, readonly) UIRefreshControl *refreshCtrl;
+@end
+
+@implementation PhotoFeedListKitViewController
+@synthesize spinner = _spinner;
+
+- (instancetype)init
+{
+  UICollectionViewFlowLayout *layout = [[UICollectionViewFlowLayout alloc] init];
+  ASCollectionNode *node = [[ASCollectionNode alloc] initWithCollectionViewLayout:layout];
+  if (self = [super initWithNode:node]) {
+    CGRect screenRect   = [[UIScreen mainScreen] bounds];
+    CGFloat screenScale = [[UIScreen mainScreen] scale];
+    CGSize screenWidthImageSize = CGSizeMake(screenRect.size.width * screenScale, screenRect.size.width * screenScale);
+    _photoFeed = [[PhotoFeedModel alloc] initWithPhotoFeedModelType:PhotoFeedModelTypePopular imageSize:screenWidthImageSize];
+
+    IGListAdapterUpdater *updater = [[IGListAdapterUpdater alloc] init];
+    _listAdapter = [[IGListAdapter alloc] initWithUpdater:updater viewController:self workingRangeSize:0];
+    _listAdapter.dataSource = self;
+    [_listAdapter setASDKCollectionNode:self.collectionNode];
+  }
+  return self;
+}
+
+- (void)viewDidLoad
+{
+  [super viewDidLoad];
+  self.collectionNode.view.alwaysBounceVertical = YES;
+  _refreshCtrl = [[UIRefreshControl alloc] init];
+  [_refreshCtrl addTarget:self action:@selector(refreshFeed) forControlEvents:UIControlEventValueChanged];
+  [self.collectionNode.view addSubview:_refreshCtrl];
+  _spinner = [[UIActivityIndicatorView alloc] initWithActivityIndicatorStyle:UIActivityIndicatorViewStyleGray];
+}
+
+- (ASCollectionNode *)collectionNode
+{
+  return self.node;
+}
+
+- (void)resetAllData
+{
+  // nop, not used currently
+}
+
+- (void)refreshFeed
+{
+  // Ask the first section controller to do the refreshing.
+  id<RefreshingSectionControllerType> secCtrl = [self.listAdapter sectionControllerForObject:self.photoFeed];
+  if ([secCtrl conformsToProtocol:@protocol(RefreshingSectionControllerType)]) {
+    [secCtrl refreshContentWithCompletion:^{
+      [self.refreshCtrl endRefreshing];
+    }];
+  }
+}
+
+- (UIActivityIndicatorView *)spinner
+{
+  if (_spinner == nil) {
+    _spinner = [[UIActivityIndicatorView alloc] initWithActivityIndicatorStyle:UIActivityIndicatorViewStyleGray];
+    [_spinner startAnimating];
+  }
+  return _spinner;
+}
+
+#pragma mark - IGListAdapterDataSource
+
+- (NSArray<id <IGListDiffable>> *)objectsForListAdapter:(IGListAdapter *)listAdapter
+{
+  return @[ self.photoFeed ];
+}
+
+- (UIView *)emptyViewForListAdapter:(IGListAdapter *)listAdapter
+{
+  return self.spinner;
+}
+
+- (IGListSectionController <IGListSectionType> *)listAdapter:(IGListAdapter *)listAdapter sectionControllerForObject:(id)object
+{
+  if ([object isKindOfClass:[PhotoFeedModel class]]) {
+    return [[PhotoFeedSectionController alloc] init];
+  } else {
+    ASDisplayNodeFailAssert(@"Only supports objects of class PhotoFeedModel.");
+    return nil;
+  }
+}
+
+@end

examples/ASDKgram/Sample/PhotoFeedModel.h

@@ -18,6 +18,7 @@
 //
 
 #import "PhotoModel.h"
+#import <IGListKit/IGListKit.h>
 
 typedef NS_ENUM(NSInteger, PhotoFeedModelType) {
   PhotoFeedModelTypePopular,
@@ -25,11 +26,13 @@ typedef NS_ENUM(NSInteger, PhotoFeedModelType) {
   PhotoFeedModelTypeUserPhotos
 };
 
-@interface PhotoFeedModel : NSObject
+@interface PhotoFeedModel : NSObject <IGListDiffable>
 
 - (instancetype)init NS_UNAVAILABLE;
 - (instancetype)initWithPhotoFeedModelType:(PhotoFeedModelType)type imageSize:(CGSize)size NS_DESIGNATED_INITIALIZER;
 
+@property (nonatomic, readonly) NSArray<PhotoModel *> *photos;
+
 - (NSUInteger)totalNumberOfPhotos;
 - (NSUInteger)numberOfItemsInFeed;
 - (PhotoModel *)objectAtIndex:(NSUInteger)index;

examples/ASDKgram/Sample/PhotoFeedModel.m

@@ -47,13 +47,6 @@
   NSUInteger    _userID;
 }
 
-#pragma mark - Properties
-
-- (NSMutableArray *)photos
-{
-  return _photos;
-}
-
 #pragma mark - Lifecycle
 
 - (instancetype)initWithPhotoFeedModelType:(PhotoFeedModelType)type imageSize:(CGSize)size
@@ -92,6 +85,11 @@
 
 #pragma mark - Instance Methods
 
+- (NSArray *)photos
+{
+  return [_photos copy];
+}
+
 - (NSUInteger)totalNumberOfPhotos
 {
   return _totalItems;
@@ -186,10 +184,13 @@
   // early return if reached end of pages
   if (_totalPages) {
     if (_currentPage == _totalPages) {
+      if (block){
+        block(@[]);
+      }
       return;
     }
   }
-  
+
   NSUInteger numPhotos = (numResults < 100) ? numResults : 100;
     
   dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
@@ -246,4 +247,16 @@
   });
 }
 
+#pragma mark - IGListDiffable
+
+- (id<NSObject>)diffIdentifier
+{
+  return self;
+}
+
+- (BOOL)isEqualToDiffableObject:(id<IGListDiffable>)object
+{
+  return self == object;
+}
+
 @end

examples/ASDKgram/Sample/PhotoFeedSectionController.h

@@ -0,0 +1,24 @@
+//
+//  PhotoFeedSectionController.h
+//  Sample
+//
+//  Created by Adlai Holler on 12/29/16.
+//  Copyright © 2016 Facebook. All rights reserved.
+//
+
+#import <IGListKit/IGListKit.h>
+#import <AsyncDisplayKit/AsyncDisplayKit.h>
+#import "RefreshingSectionControllerType.h"
+#import "ASCollectionSectionController.h"
+
+@class PhotoFeedModel;
+
+NS_ASSUME_NONNULL_BEGIN
+
+@interface PhotoFeedSectionController : ASCollectionSectionController <IGListSectionType, ASSectionController, RefreshingSectionControllerType>
+
+@property (nonatomic, strong, nullable) PhotoFeedModel *photoFeed;
+
+@end
+
+NS_ASSUME_NONNULL_END

examples/ASDKgram/Sample/PhotoFeedSectionController.m

@@ -0,0 +1,122 @@
+//
+//  PhotoFeedSectionController.m
+//  Sample
+//
+//  Created by Adlai Holler on 12/29/16.
+//  Copyright © 2016 Facebook. All rights reserved.
+//
+
+#import "PhotoFeedSectionController.h"
+#import "PhotoFeedModel.h"
+#import "PhotoModel.h"
+#import "PhotoCellNode.h"
+#import "TailLoadingNode.h"
+#import "FeedHeaderNode.h"
+
+@interface PhotoFeedSectionController () <ASSupplementaryNodeSource, IGListSupplementaryViewSource>
+@property (nonatomic, strong) NSString *paginatingSpinner;
+@end
+
+@implementation PhotoFeedSectionController
+
+- (instancetype)init
+{
+  if (self = [super init]) {
+    _paginatingSpinner = @"Paginating Spinner";
+    self.supplementaryViewSource = self;
+  }
+  return self;
+}
+
+#pragma mark - IGListSectionType
+
+- (void)didUpdateToObject:(id)object
+{
+  _photoFeed = object;
+  [self setItems:_photoFeed.photos animated:NO completion:nil];
+}
+
+
+ASIGSectionControllerSizeForItemImplementation;
+ASIGSectionControllerCellForIndexImplementation;
+
+- (void)didSelectItemAtIndex:(NSInteger)index
+{
+  // nop
+}
+
+#pragma mark - ASSectionController
+
+- (ASCellNodeBlock)nodeBlockForItemAtIndex:(NSInteger)index
+{
+  id object = self.items[index];
+  // this will be executed on a background thread - important to make sure it's thread safe
+  ASCellNode *(^nodeBlock)() = nil;
+  if (object == _paginatingSpinner) {
+    nodeBlock = ^{
+      return [[TailLoadingNode alloc] init];
+    };
+  } else if ([object isKindOfClass:[PhotoModel class]]) {
+    PhotoModel *photoModel = object;
+    nodeBlock = ^{
+      PhotoCellNode *cellNode = [[PhotoCellNode alloc] initWithPhotoObject:photoModel];
+      return cellNode;
+    };
+  }
+
+  return nodeBlock;
+}
+
+- (void)beginBatchFetchWithContext:(ASBatchContext *)context
+{
+  // Immediately add the loading spinner if needed.
+  if (self.items.count > 0) {
+    NSArray *newItems = [self.items arrayByAddingObject:_paginatingSpinner];
+    [self setItems:newItems animated:NO completion:nil];
+  }
+
+  // Start the fetch, then update the items (removing the spinner) when they are loaded.
+  [_photoFeed requestPageWithCompletionBlock:^(NSArray *newPhotos){
+    [self setItems:_photoFeed.photos animated:NO completion:^{
+      [context completeBatchFetching:YES];
+    }];
+  } numResultsToReturn:20];
+}
+
+#pragma mark - RefreshingSectionControllerType
+
+- (void)refreshContentWithCompletion:(void(^)())completion
+{
+  [_photoFeed refreshFeedWithCompletionBlock:^(NSArray *addedItems) {
+    [self setItems:_photoFeed.photos animated:YES completion:completion];
+  } numResultsToReturn:4];
+}
+
+#pragma mark - ASSupplementaryNodeSource
+
+- (ASCellNode *)nodeForSupplementaryElementOfKind:(NSString *)elementKind atIndex:(NSInteger)index
+{
+  ASDisplayNodeAssert([elementKind isEqualToString:UICollectionElementKindSectionHeader], nil);
+  return [[FeedHeaderNode alloc] init];
+}
+
+- (ASSizeRange)sizeRangeForSupplementaryElementOfKind:(NSString *)elementKind atIndex:(NSInteger)index
+{
+  if ([elementKind isEqualToString:UICollectionElementKindSectionHeader]) {
+    return ASSizeRangeUnconstrained;
+  } else {
+    return ASSizeRangeZero;
+  }
+}
+
+#pragma mark - IGListSupplementaryViewSource
+
+- (NSArray<NSString *> *)supportedElementKinds
+{
+  return @[ UICollectionElementKindSectionHeader ];
+}
+
+ASIGSupplementarySourceViewForSupplementaryElementImplementation(self);
+ASIGSupplementarySourceSizeForSupplementaryElementImplementation;
+
+@end

examples/ASDKgram/Sample/PhotoModel.h

@@ -17,12 +17,12 @@
 //  CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 //
 
-#import "CoreGraphics/CoreGraphics.h"
 #import "UserModel.h"
 #import "LocationModel.h"
 #import "CommentFeedModel.h"
+#import <IGListKit/IGListKit.h>
 
-@interface PhotoModel : NSObject
+@interface PhotoModel : NSObject <IGListDiffable>
 
 @property (nonatomic, strong, readonly) NSURL                  *URL;
 @property (nonatomic, strong, readonly) NSString               *photoID;

examples/ASDKgram/Sample/PhotoModel.m

@@ -83,11 +83,7 @@
 
 - (NSAttributedString *)likesAttributedStringWithFontSize:(CGFloat)size
 {
-  NSNumberFormatter *formatter = [[NSNumberFormatter alloc] init];
+  NSString *likesString = [NSString stringWithFormat:@"♥︎ %lu likes", (unsigned long)_likesCount];
-  [formatter setNumberStyle:NSNumberFormatterDecimalStyle];
-  NSString *formattedLikesNumber = [formatter stringFromNumber:[[NSNumber alloc] initWithUnsignedInteger:self.likesCount]];
-  
-  NSString *likesString = [NSString stringWithFormat:@"♥︎ %@ likes", formattedLikesNumber];
 
   return [NSAttributedString attributedStringWithString:likesString fontSize:size color:[UIColor darkBlueColor] firstWordColor:nil];
 }
@@ -102,4 +98,14 @@
   return [NSString stringWithFormat:@"%@ - %@", _photoID, _descriptionText];
 }
 
-@end
+- (id<NSObject>)diffIdentifier
+{
+  return self.photoID;
+}
+
+- (BOOL)isEqualToDiffableObject:(id<IGListDiffable>)object
+{
+  return [self isEqual:object];
+}
+
+@end

examples/ASDKgram/Sample/RefreshingSectionControllerType.h

@@ -0,0 +1,19 @@
+//
+//  RefreshingSectionControllerType.h
+//  Sample
+//
+//  Created by Adlai Holler on 12/29/16.
+//  Copyright © 2016 Facebook. All rights reserved.
+//
+
+#import <IGListKit/IGListKit.h>
+
+NS_ASSUME_NONNULL_BEGIN
+
+@protocol RefreshingSectionControllerType <IGListSectionType>
+
+- (void)refreshContentWithCompletion:(nullable void(^)())completion;
+
+@end
+
+NS_ASSUME_NONNULL_END

examples/ASDKgram/Sample/TailLoadingNode.h

@@ -0,0 +1,17 @@
+//
+//  TailLoadingNode.h
+//  Sample
+//
+//  Created by Adlai Holler on 1/3/17.
+//  Copyright © 2017 Facebook. All rights reserved.
+//
+
+#import <AsyncDisplayKit/AsyncDisplayKit.h>
+
+/**
+ * A node that shows a UIActivityIndicatorView, useful for putting at the end of a 
+ * list while the next page is loading.
+ */
+@interface TailLoadingNode : ASCellNode
+
+@end

examples/ASDKgram/Sample/TailLoadingNode.m

@@ -0,0 +1,35 @@
+//
+//  TailLoadingNode.m
+//  Sample
+//
+//  Created by Adlai Holler on 1/3/17.
+//  Copyright © 2017 Facebook. All rights reserved.
+//
+
+#import "TailLoadingNode.h"
+
+@interface TailLoadingNode ()
+@property (nonatomic, strong) ASDisplayNode *activityIndicatorNode;
+@end
+
+@implementation TailLoadingNode
+
+- (instancetype)init
+{
+  if (self = [super init]) {
+    _activityIndicatorNode = [[ASDisplayNode alloc] initWithViewBlock:^{
+      UIActivityIndicatorView *v = [[UIActivityIndicatorView alloc] initWithActivityIndicatorStyle:UIActivityIndicatorViewStyleGray];
+      [v startAnimating];
+      return v;
+    }];
+    self.style.height = ASDimensionMake(100);
+  }
+  return self;
+}
+
+- (ASLayoutSpec *)layoutSpecThatFits:(ASSizeRange)constrainedSize
+{
+  return [ASCenterLayoutSpec centerLayoutSpecWithCenteringOptions:ASCenterLayoutSpecCenteringXY sizingOptions:ASCenterLayoutSpecSizingOptionMinimumXY child:self.activityIndicatorNode];
+}
+
+@end