Merge branch 'develop' into feature/monarch

MVMCoreUI.xcodeproj/project.pbxproj

@@ -170,8 +170,15 @@
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 		5822720C2B1FC55F00F75BAE /* RotorHandler.swift in Sources */ = {isa = PBXBuildFile; fileRef = 5822720A2B1FC55F00F75BAE /* RotorHandler.swift */; };
+		583335592BF64E77001D90D7 /* MVMCoreUITests.swift in Sources */ = {isa = PBXBuildFile; fileRef = 583335582BF64E77001D90D7 /* MVMCoreUITests.swift */; };
+		5833355A2BF64E77001D90D7 /* MVMCoreUI.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = D29DF0CC21E404D4003B2FB9 /* MVMCoreUI.framework */; };
+		583335632BF6509C001D90D7 /* UAD_page_model.json in Resources */ = {isa = PBXBuildFile; fileRef = 583335622BF6509C001D90D7 /* UAD_page_model.json */; };
+		583335652BF6A5C3001D90D7 /* TestUtils.swift in Sources */ = {isa = PBXBuildFile; fileRef = 583335642BF6A5C3001D90D7 /* TestUtils.swift */; };
+		583335672BF6DCD0001D90D7 /* UAD_page_model_2.json in Resources */ = {isa = PBXBuildFile; fileRef = 583335662BF6DCD0001D90D7 /* UAD_page_model_2.json */; };
+		5833356D2BFBF51C001D90D7 /* UAD_page_model_3.json in Resources */ = {isa = PBXBuildFile; fileRef = 5833356C2BFBF51C001D90D7 /* UAD_page_model_3.json */; };
 		5846ABF62B4762A600FA6C76 /* PollingBehaviorModel.swift in Sources */ = {isa = PBXBuildFile; fileRef = 5846ABF52B4762A600FA6C76 /* PollingBehaviorModel.swift */; };
 		58A9DD7D2AC2103300F5E0B0 /* ReplaceableMoleculeBehaviorModel.swift in Sources */ = {isa = PBXBuildFile; fileRef = 58A9DD7C2AC2103300F5E0B0 /* ReplaceableMoleculeBehaviorModel.swift */; };
+		58E7561D2BE04C320088BB5D /* MoleculeComparisonProtocol.swift in Sources */ = {isa = PBXBuildFile; fileRef = 58E7561C2BE04C320088BB5D /* MoleculeComparisonProtocol.swift */; };
 		608211282AC6B57E00C3FC39 /* MVMCoreUILoggingHandler.swift in Sources */ = {isa = PBXBuildFile; fileRef = 608211262AC6AF8200C3FC39 /* MVMCoreUILoggingHandler.swift */; };
 		8D070BB0241B56530099AC56 /* ListRightVariableTotalDataModel.swift in Sources */ = {isa = PBXBuildFile; fileRef = 8D070BAF241B56530099AC56 /* ListRightVariableTotalDataModel.swift */; };
 		8D070BB2241B56AD0099AC56 /* ListRightVariableTotalData.swift in Sources */ = {isa = PBXBuildFile; fileRef = 8D070BB1241B56AD0099AC56 /* ListRightVariableTotalData.swift */; };
@@ -608,6 +615,16 @@
 		FD99130028E21E4900542CC3 /* RuleNotEqualsModel.swift in Sources */ = {isa = PBXBuildFile; fileRef = FD9912FF28E21E4900542CC3 /* RuleNotEqualsModel.swift */; };
 /* End PBXBuildFile section */
 
+/* Begin PBXContainerItemProxy section */
+		5833355B2BF64E77001D90D7 /* PBXContainerItemProxy */ = {
+			isa = PBXContainerItemProxy;
+			containerPortal = D29DF0C321E404D4003B2FB9 /* Project object */;
+			proxyType = 1;
+			remoteGlobalIDString = D29DF0CB21E404D4003B2FB9;
+			remoteInfo = MVMCoreUI;
+		};
+/* End PBXContainerItemProxy section */
+
 /* Begin PBXFileReference section */
 		01004F2F22721C3800991ECC /* RadioButton.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = RadioButton.swift; sourceTree = "<group>"; };
 		0103B84D23D7E33A009C315C /* HeadlineBodyToggleModel.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = HeadlineBodyToggleModel.swift; sourceTree = "<group>"; };
@@ -775,10 +792,17 @@
 		52B201D124081CFB00D2011E /* ListLeftVariableRadioButtonAndPaymentMethodModel.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = ListLeftVariableRadioButtonAndPaymentMethodModel.swift; sourceTree = "<group>"; };
 		582272092B1FC55F00F75BAE /* AccessibilityHandler.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = AccessibilityHandler.swift; sourceTree = "<group>"; };
 		5822720A2B1FC55F00F75BAE /* RotorHandler.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = RotorHandler.swift; sourceTree = "<group>"; };
+		583335562BF64E77001D90D7 /* MVMCoreUITests.xctest */ = {isa = PBXFileReference; explicitFileType = wrapper.cfbundle; includeInIndex = 0; path = MVMCoreUITests.xctest; sourceTree = BUILT_PRODUCTS_DIR; };
+		583335582BF64E77001D90D7 /* MVMCoreUITests.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = MVMCoreUITests.swift; sourceTree = "<group>"; };
+		583335622BF6509C001D90D7 /* UAD_page_model.json */ = {isa = PBXFileReference; lastKnownFileType = text.json; path = UAD_page_model.json; sourceTree = "<group>"; };
+		583335642BF6A5C3001D90D7 /* TestUtils.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = TestUtils.swift; sourceTree = "<group>"; };
+		583335662BF6DCD0001D90D7 /* UAD_page_model_2.json */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = text.json; path = UAD_page_model_2.json; sourceTree = "<group>"; };
+		5833356C2BFBF51C001D90D7 /* UAD_page_model_3.json */ = {isa = PBXFileReference; lastKnownFileType = text.json; path = UAD_page_model_3.json; sourceTree = "<group>"; };
 		5846ABF52B4762A600FA6C76 /* PollingBehaviorModel.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = PollingBehaviorModel.swift; sourceTree = "<group>"; };
 		5878F0A42BD7E68800ADE23D /* mvmcoreui.xcconfig */ = {isa = PBXFileReference; lastKnownFileType = text.xcconfig; path = mvmcoreui.xcconfig; sourceTree = "<group>"; };
 		5878F0A52BD7E6BE00ADE23D /* mvmcoreui_dev.xcconfig */ = {isa = PBXFileReference; lastKnownFileType = text.xcconfig; path = mvmcoreui_dev.xcconfig; sourceTree = "<group>"; };
 		58A9DD7C2AC2103300F5E0B0 /* ReplaceableMoleculeBehaviorModel.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = ReplaceableMoleculeBehaviorModel.swift; sourceTree = "<group>"; };
+		58E7561C2BE04C320088BB5D /* MoleculeComparisonProtocol.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = MoleculeComparisonProtocol.swift; sourceTree = "<group>"; };
 		608211262AC6AF8200C3FC39 /* MVMCoreUILoggingHandler.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = MVMCoreUILoggingHandler.swift; sourceTree = "<group>"; };
 		8D070BAF241B56530099AC56 /* ListRightVariableTotalDataModel.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = ListRightVariableTotalDataModel.swift; sourceTree = "<group>"; };
 		8D070BB1241B56AD0099AC56 /* ListRightVariableTotalData.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = ListRightVariableTotalData.swift; sourceTree = "<group>"; };
@@ -1220,6 +1244,14 @@
 /* End PBXFileReference section */
 
 /* Begin PBXFrameworksBuildPhase section */
+		583335532BF64E77001D90D7 /* Frameworks */ = {
+			isa = PBXFrameworksBuildPhase;
+			buildActionMask = 2147483647;
+			files = (
+				5833355A2BF64E77001D90D7 /* MVMCoreUI.framework in Frameworks */,
+			);
+			runOnlyForDeploymentPostprocessing = 0;
+		};
 		D29DF0C921E404D4003B2FB9 /* Frameworks */ = {
 			isa = PBXFrameworksBuildPhase;
 			buildActionMask = 2147483647;
@@ -1253,6 +1285,7 @@
 				D28BA74C248589C800B75CB8 /* TabPageModelProtocol.swift */,
 				27F6B08B26052AFF008529AA /* ParentMoleculeModelProtocol.swift */,
 				27577DCC286CA959001EC47E /* MoleculeMaskingProtocol.swift */,
+				58E7561C2BE04C320088BB5D /* MoleculeComparisonProtocol.swift */,
 			);
 			path = ModelProtocols;
 			sourceTree = "<group>";
@@ -1503,6 +1536,34 @@
 			path = Accessibility;
 			sourceTree = "<group>";
 		};
+		583335572BF64E77001D90D7 /* MVMCoreUITests */ = {
+			isa = PBXGroup;
+			children = (
+				583335602BF65063001D90D7 /* JSON */,
+				583335582BF64E77001D90D7 /* MVMCoreUITests.swift */,
+				583335642BF6A5C3001D90D7 /* TestUtils.swift */,
+			);
+			path = MVMCoreUITests;
+			sourceTree = "<group>";
+		};
+		583335602BF65063001D90D7 /* JSON */ = {
+			isa = PBXGroup;
+			children = (
+				583335612BF6506C001D90D7 /* Modelling */,
+			);
+			path = JSON;
+			sourceTree = "<group>";
+		};
+		583335612BF6506C001D90D7 /* Modelling */ = {
+			isa = PBXGroup;
+			children = (
+				583335662BF6DCD0001D90D7 /* UAD_page_model_2.json */,
+				583335622BF6509C001D90D7 /* UAD_page_model.json */,
+				5833356C2BFBF51C001D90D7 /* UAD_page_model_3.json */,
+			);
+			path = Modelling;
+			sourceTree = "<group>";
+		};
 		8DD1E36C243B3CD900D8F2DF /* ThreeColumn */ = {
 			isa = PBXGroup;
 			children = (
@@ -2012,6 +2073,7 @@
 			isa = PBXGroup;
 			children = (
 				D29DF0CE21E404D4003B2FB9 /* MVMCoreUI */,
+				583335572BF64E77001D90D7 /* MVMCoreUITests */,
 				D29DF0CD21E404D4003B2FB9 /* Products */,
 				D29DF0E421E4F3C7003B2FB9 /* Frameworks */,
 			);
@@ -2021,6 +2083,7 @@
 			isa = PBXGroup;
 			children = (
 				D29DF0CC21E404D4003B2FB9 /* MVMCoreUI.framework */,
+				583335562BF64E77001D90D7 /* MVMCoreUITests.xctest */,
 			);
 			name = Products;
 			sourceTree = "<group>";
@@ -2597,6 +2660,24 @@
 /* End PBXHeadersBuildPhase section */
 
 /* Begin PBXNativeTarget section */
+		583335552BF64E77001D90D7 /* MVMCoreUITests */ = {
+			isa = PBXNativeTarget;
+			buildConfigurationList = 5833355F2BF64E77001D90D7 /* Build configuration list for PBXNativeTarget "MVMCoreUITests" */;
+			buildPhases = (
+				583335522BF64E77001D90D7 /* Sources */,
+				583335532BF64E77001D90D7 /* Frameworks */,
+				583335542BF64E77001D90D7 /* Resources */,
+			);
+			buildRules = (
+			);
+			dependencies = (
+				5833355C2BF64E77001D90D7 /* PBXTargetDependency */,
+			);
+			name = MVMCoreUITests;
+			productName = MVMCoreUITests;
+			productReference = 583335562BF64E77001D90D7 /* MVMCoreUITests.xctest */;
+			productType = "com.apple.product-type.bundle.unit-test";
+		};
 		D29DF0CB21E404D4003B2FB9 /* MVMCoreUI */ = {
 			isa = PBXNativeTarget;
 			buildConfigurationList = D29DF0D421E404D4003B2FB9 /* Build configuration list for PBXNativeTarget "MVMCoreUI" */;
@@ -2621,9 +2702,13 @@
 		D29DF0C321E404D4003B2FB9 /* Project object */ = {
 			isa = PBXProject;
 			attributes = {
+				LastSwiftUpdateCheck = 1540;
 				LastUpgradeCheck = 1320;
 				ORGANIZATIONNAME = "Verizon Wireless";
 				TargetAttributes = {
+					583335552BF64E77001D90D7 = {
+						CreatedOnToolsVersion = 15.4;
+					};
 					D29DF0CB21E404D4003B2FB9 = {
 						CreatedOnToolsVersion = 10.1;
 						LastSwiftMigration = 1010;
@@ -2646,11 +2731,22 @@
 			projectRoot = "";
 			targets = (
 				D29DF0CB21E404D4003B2FB9 /* MVMCoreUI */,
+				583335552BF64E77001D90D7 /* MVMCoreUITests */,
 			);
 		};
 /* End PBXProject section */
 
 /* Begin PBXResourcesBuildPhase section */
+		583335542BF64E77001D90D7 /* Resources */ = {
+			isa = PBXResourcesBuildPhase;
+			buildActionMask = 2147483647;
+			files = (
+				583335672BF6DCD0001D90D7 /* UAD_page_model_2.json in Resources */,
+				5833356D2BFBF51C001D90D7 /* UAD_page_model_3.json in Resources */,
+				583335632BF6509C001D90D7 /* UAD_page_model.json in Resources */,
+			);
+			runOnlyForDeploymentPostprocessing = 0;
+		};
 		D29DF0CA21E404D4003B2FB9 /* Resources */ = {
 			isa = PBXResourcesBuildPhase;
 			buildActionMask = 2147483647;
@@ -2669,6 +2765,15 @@
 /* End PBXResourcesBuildPhase section */
 
 /* Begin PBXSourcesBuildPhase section */
+		583335522BF64E77001D90D7 /* Sources */ = {
+			isa = PBXSourcesBuildPhase;
+			buildActionMask = 2147483647;
+			files = (
+				583335592BF64E77001D90D7 /* MVMCoreUITests.swift in Sources */,
+				583335652BF6A5C3001D90D7 /* TestUtils.swift in Sources */,
+			);
+			runOnlyForDeploymentPostprocessing = 0;
+		};
 		D29DF0C821E404D4003B2FB9 /* Sources */ = {
 			isa = PBXSourcesBuildPhase;
 			buildActionMask = 2147483647;
@@ -3009,6 +3114,7 @@
 				EA1758482BC97ED800A5C0D9 /* BadgeIndicator.swift in Sources */,
 				012A88B1238C880100FE3DA1 /* CarouselPagingModelProtocol.swift in Sources */,
 				0A9D091E2433796500D2E6C0 /* NumericCarouselIndicatorModel.swift in Sources */,
+				58E7561D2BE04C320088BB5D /* MoleculeComparisonProtocol.swift in Sources */,
 				D29DF2C921E7BFC6003B2FB9 /* MFSizeObject.m in Sources */,
 				AF1C336928859778006B1001 /* ActionAlertHandler.swift in Sources */,
 				9445890E2385C3F800DE9FD4 /* MultiProgressModel.swift in Sources */,
@@ -3240,6 +3346,14 @@
 		};
 /* End PBXSourcesBuildPhase section */
 
+/* Begin PBXTargetDependency section */
+		5833355C2BF64E77001D90D7 /* PBXTargetDependency */ = {
+			isa = PBXTargetDependency;
+			target = D29DF0CB21E404D4003B2FB9 /* MVMCoreUI */;
+			targetProxy = 5833355B2BF64E77001D90D7 /* PBXContainerItemProxy */;
+		};
+/* End PBXTargetDependency section */
+
 /* Begin PBXVariantGroup section */
 		D29DF32821EE8736003B2FB9 /* Localizable.strings */ = {
 			isa = PBXVariantGroup;
@@ -3254,6 +3368,49 @@
 /* End PBXVariantGroup section */
 
 /* Begin XCBuildConfiguration section */
+		5833355D2BF64E77001D90D7 /* Debug */ = {
+			isa = XCBuildConfiguration;
+			buildSettings = {
+				ASSETCATALOG_COMPILER_GENERATE_SWIFT_ASSET_SYMBOL_EXTENSIONS = YES;
+				CLANG_CXX_LANGUAGE_STANDARD = "gnu++20";
+				CODE_SIGN_STYLE = Automatic;
+				CURRENT_PROJECT_VERSION = 1;
+				ENABLE_USER_SCRIPT_SANDBOXING = YES;
+				GCC_C_LANGUAGE_STANDARD = gnu17;
+				GENERATE_INFOPLIST_FILE = YES;
+				IPHONEOS_DEPLOYMENT_TARGET = 17.5;
+				LOCALIZATION_PREFERS_STRING_CATALOGS = YES;
+				MARKETING_VERSION = 1.0;
+				PRODUCT_BUNDLE_IDENTIFIER = com.vzw.MVMCoreUITests;
+				PRODUCT_NAME = "$(TARGET_NAME)";
+				SWIFT_ACTIVE_COMPILATION_CONDITIONS = "DEBUG $(inherited)";
+				SWIFT_EMIT_LOC_STRINGS = NO;
+				SWIFT_VERSION = 5.0;
+				TARGETED_DEVICE_FAMILY = "1,2";
+			};
+			name = Debug;
+		};
+		5833355E2BF64E77001D90D7 /* Release */ = {
+			isa = XCBuildConfiguration;
+			buildSettings = {
+				ASSETCATALOG_COMPILER_GENERATE_SWIFT_ASSET_SYMBOL_EXTENSIONS = YES;
+				CLANG_CXX_LANGUAGE_STANDARD = "gnu++20";
+				CODE_SIGN_STYLE = Automatic;
+				CURRENT_PROJECT_VERSION = 1;
+				ENABLE_USER_SCRIPT_SANDBOXING = YES;
+				GCC_C_LANGUAGE_STANDARD = gnu17;
+				GENERATE_INFOPLIST_FILE = YES;
+				IPHONEOS_DEPLOYMENT_TARGET = 17.5;
+				LOCALIZATION_PREFERS_STRING_CATALOGS = YES;
+				MARKETING_VERSION = 1.0;
+				PRODUCT_BUNDLE_IDENTIFIER = com.vzw.MVMCoreUITests;
+				PRODUCT_NAME = "$(TARGET_NAME)";
+				SWIFT_EMIT_LOC_STRINGS = NO;
+				SWIFT_VERSION = 5.0;
+				TARGETED_DEVICE_FAMILY = "1,2";
+			};
+			name = Release;
+		};
 		D29DF0D221E404D4003B2FB9 /* Debug */ = {
 			isa = XCBuildConfiguration;
 			baseConfigurationReference = 5878F0A52BD7E6BE00ADE23D /* mvmcoreui_dev.xcconfig */;
@@ -3446,6 +3603,15 @@
 /* End XCBuildConfiguration section */
 
 /* Begin XCConfigurationList section */
+		5833355F2BF64E77001D90D7 /* Build configuration list for PBXNativeTarget "MVMCoreUITests" */ = {
+			isa = XCConfigurationList;
+			buildConfigurations = (
+				5833355D2BF64E77001D90D7 /* Debug */,
+				5833355E2BF64E77001D90D7 /* Release */,
+			);
+			defaultConfigurationIsVisible = 0;
+			defaultConfigurationName = Release;
+		};
 		D29DF0C621E404D4003B2FB9 /* Build configuration list for PBXProject "MVMCoreUI" */ = {
 			isa = XCConfigurationList;
 			buildConfigurations = (

MVMCoreUI.xcodeproj/xcshareddata/xcschemes/MVMCoreUI.xcscheme

@@ -0,0 +1,67 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<Scheme
+   LastUpgradeVersion = "1540"
+   version = "1.7">
+   <BuildAction
+      parallelizeBuildables = "YES"
+      buildImplicitDependencies = "YES"
+      buildArchitectures = "Automatic">
+      <BuildActionEntries>
+         <BuildActionEntry
+            buildForTesting = "YES"
+            buildForRunning = "YES"
+            buildForProfiling = "YES"
+            buildForArchiving = "YES"
+            buildForAnalyzing = "YES">
+            <BuildableReference
+               BuildableIdentifier = "primary"
+               BlueprintIdentifier = "D29DF0CB21E404D4003B2FB9"
+               BuildableName = "MVMCoreUI.framework"
+               BlueprintName = "MVMCoreUI"
+               ReferencedContainer = "container:MVMCoreUI.xcodeproj">
+            </BuildableReference>
+         </BuildActionEntry>
+      </BuildActionEntries>
+   </BuildAction>
+   <TestAction
+      buildConfiguration = "Debug"
+      selectedDebuggerIdentifier = "Xcode.DebuggerFoundation.Debugger.LLDB"
+      selectedLauncherIdentifier = "Xcode.DebuggerFoundation.Launcher.LLDB"
+      shouldUseLaunchSchemeArgsEnv = "YES"
+      shouldAutocreateTestPlan = "YES">
+   </TestAction>
+   <LaunchAction
+      buildConfiguration = "Debug"
+      selectedDebuggerIdentifier = "Xcode.DebuggerFoundation.Debugger.LLDB"
+      selectedLauncherIdentifier = "Xcode.DebuggerFoundation.Launcher.LLDB"
+      launchStyle = "0"
+      useCustomWorkingDirectory = "NO"
+      ignoresPersistentStateOnLaunch = "NO"
+      debugDocumentVersioning = "YES"
+      debugServiceExtension = "internal"
+      allowLocationSimulation = "YES">
+   </LaunchAction>
+   <ProfileAction
+      buildConfiguration = "Release"
+      shouldUseLaunchSchemeArgsEnv = "YES"
+      savedToolIdentifier = ""
+      useCustomWorkingDirectory = "NO"
+      debugDocumentVersioning = "YES">
+      <MacroExpansion>
+         <BuildableReference
+            BuildableIdentifier = "primary"
+            BlueprintIdentifier = "D29DF0CB21E404D4003B2FB9"
+            BuildableName = "MVMCoreUI.framework"
+            BlueprintName = "MVMCoreUI"
+            ReferencedContainer = "container:MVMCoreUI.xcodeproj">
+         </BuildableReference>
+      </MacroExpansion>
+   </ProfileAction>
+   <AnalyzeAction
+      buildConfiguration = "Debug">
+   </AnalyzeAction>
+   <ArchiveAction
+      buildConfiguration = "Release"
+      revealArchiveInOrganizer = "YES">
+   </ArchiveAction>
+</Scheme>

MVMCoreUI/Atomic/Actions/ActionAlertModel.swift

@@ -25,4 +25,11 @@ public struct ActionAlertModel: ActionModelProtocol {
     public init(alert: AlertModel) {
         self.alert = alert
     }
+    
+    public func isEqual(to model: any ModelComparisonProtocol) -> Bool {
+        guard let model = model as? Self else { return false }
+        return model.extraParameters == extraParameters
+        && model.analyticsData == analyticsData
+        && model.alert == alert
+    }
 }

MVMCoreUI/Atomic/Actions/ActionCollapseNotificationModel.swift

@@ -20,4 +20,12 @@ public struct ActionCollapseNotificationModel: ActionModelProtocol {
         self.extraParameters = extraParameters
         self.analyticsData = analyticsData
     }
+    
+    // Default
+    //public func isEqual(to model: any ModelComparisonProtocol) -> Bool {
+    //    guard let model = model as? Self else { return false }
+    //    return model.actionType == actionType
+    //    && model.extraParameters == extraParameters
+    //    && model.analyticsData == analyticsData
+    //}
 }

MVMCoreUI/Atomic/Actions/ActionDismissNotificationModel.swift

@@ -20,4 +20,12 @@ public struct ActionDismissNotificationModel: ActionModelProtocol {
         self.extraParameters = extraParameters
         self.analyticsData = analyticsData
     }
+    
+    // Default
+    // public func isEqual(to model: any ModelComparisonProtocol) -> Bool {
+    //    guard let model = model as? Self else { return false }
+    //    return model.actionType == actionType
+    //    && model.extraParameters == extraParameters
+    //    && model.analyticsData == analyticsData
+    //}
 }

MVMCoreUI/Atomic/Actions/ActionOpenPanelModel.swift

@@ -29,4 +29,12 @@ public struct ActionOpenPanelModel: ActionModelProtocol {
         self.extraParameters = extraParameters
         self.analyticsData = analyticsData
     }
+    
+    // Default
+    public func isEqual(to model: any ModelComparisonProtocol) -> Bool {
+        guard let model = model as? Self else { return false }
+        return model.extraParameters == extraParameters
+        && model.analyticsData == analyticsData
+        && model.panel == panel
+    }
 }

MVMCoreUI/Atomic/Actions/ActionTopNotificationModel.swift

@@ -22,4 +22,11 @@ public struct ActionTopNotificationModel: ActionModelProtocol {
         self.extraParameters = extraParameters
         self.analyticsData = analyticsData
     }
+    
+    public func isEqual(to model: any ModelComparisonProtocol) -> Bool {
+        guard let model = model as? Self else { return false }
+        return model.extraParameters == extraParameters
+        && model.analyticsData == analyticsData
+        && model.topNotification == topNotification
+    }
 }

MVMCoreUI/Atomic/Actions/AlertModel.swift

@@ -9,7 +9,8 @@
 import UIKit
 import MVMCore
 
-public struct AlertButtonModel: Codable {
+public struct AlertButtonModel: Codable, Equatable {
+    
     //--------------------------------------------------
     // MARK: - Properties
     //--------------------------------------------------
@@ -62,9 +63,16 @@ public struct AlertButtonModel: Codable {
         try container.encodeModel(action, forKey: .action)
         try container.encodeIfPresent(preferred, forKey: .preferred)
     }
+    
+    public static func == (lhs: AlertButtonModel, rhs: AlertButtonModel) -> Bool {
+        lhs.title == rhs.title
+        && lhs.preferred == rhs.preferred
+        && lhs.style == rhs.style
+        && lhs.action.isEqual(to: rhs.action)
+    }
 }
 
-public struct AlertModel: Codable, Identifiable, AlertModelProtocol {
+public struct AlertModel: Codable, Identifiable, Equatable, AlertModelProtocol {
     
     //--------------------------------------------------
     // MARK: - Properties
@@ -95,7 +103,6 @@ public struct AlertModel: Codable, Identifiable, AlertModelProtocol {
         }
     }
     
-
     //--------------------------------------------------
     // MARK: - Init
     //--------------------------------------------------
@@ -149,6 +156,14 @@ public struct AlertModel: Codable, Identifiable, AlertModelProtocol {
         try container.encodeIfPresent(analyticsData, forKey: .analyticsData)
         try container.encode(id, forKey: .id)
     }
+    
+    public static func == (lhs: AlertModel, rhs: AlertModel) -> Bool {
+        lhs.title == rhs.title
+        && lhs.message == rhs.message
+        && lhs.preferredStyle == rhs.preferredStyle
+        && lhs.buttonModels == rhs.buttonModels
+        && lhs.analyticsData == rhs.analyticsData
+    }
 }
 
 public extension AlertButtonModel {

MVMCoreUI/Atomic/Atoms/Buttons/ButtonGroupModel.swift

@@ -79,4 +79,16 @@ public class ButtonGroupModel: ParentMoleculeModelProtocol {
         try container.encodeIfPresent(childWidthValue, forKey: .childWidthValue)
         try container.encodeIfPresent(childWidthPercentage, forKey: .childWidthPercentage)
     }
+
+    public func isEqual(to model: any ModelComparisonProtocol) -> Bool {
+        guard let model = model as? Self else { return false }
+        return buttons.count == model.buttons.count
+        && surface == model.surface
+        && enabled == model.enabled
+        && alignment == model.alignment
+        && rowQuantityPhone == model.rowQuantityPhone
+        && rowQuantityTablet == model.rowQuantityTablet
+        && childWidthValue == model.childWidthValue
+        && childWidthPercentage == model.childWidthPercentage
+    }
 }

MVMCoreUI/Atomic/Atoms/Buttons/ButtonModel.swift

@@ -186,4 +186,34 @@ open class ButtonModel: ButtonModelProtocol, MoleculeModelProtocol, FormGroupWat
         try container.encodeIfPresent(accessibilityTraits, forKey: .accessibilityTraits)
         try container.encodeIfPresent(disabledAccessibilityTraits, forKey: .disabledAccessibilityTraits)
     }
+    
+    public func isEqual(to model: any ModelComparisonProtocol) -> Bool {
+        guard let model = model as? Self else { return false }
+        return title == model.title
+        && enabled == model.enabled
+        && inverted == model.inverted
+        && accessibilityText == model.accessibilityText
+        && accessibilityIdentifier == model.accessibilityIdentifier
+        && accessibilityTraits == model.accessibilityTraits
+        && disabledAccessibilityTraits == model.disabledAccessibilityTraits
+        && style == model.style
+        && size == model.size
+        && groupName == model.groupName
+        && width == model.width
+        && action.isEqual(to: model.action)
+    }
+    
+    public func isVisuallyEquivalent(to model: any MoleculeModelComparisonProtocol) -> Bool {
+        guard let model = model as? Self else { return false }
+        return title == model.title
+        && enabled == model.enabled
+        && inverted == model.inverted
+        && accessibilityText == model.accessibilityText
+        && accessibilityIdentifier == model.accessibilityIdentifier
+        && accessibilityTraits == model.accessibilityTraits
+        && disabledAccessibilityTraits == model.disabledAccessibilityTraits
+        && style == model.style
+        && size == model.size
+        && width == model.width
+    }
 }

MVMCoreUI/Atomic/Atoms/Buttons/ImageButtonModel.swift

@@ -33,7 +33,7 @@ open class ImageButtonModel: ButtonModelProtocol, MoleculeModelProtocol, FormGro
         [image].compactMap({$0})
     }
     
-    public func replaceChildMolecule(with molecule: MoleculeModelProtocol) throws -> Bool {
+    public func replaceChildMolecule(with molecule: MoleculeModelProtocol) throws -> MoleculeModelProtocol? {
         return try replaceChildMolecule(at: &image, with: molecule)
     }
     

MVMCoreUI/Atomic/Atoms/Buttons/Link/LinkModel.swift

@@ -99,6 +99,30 @@ open class LinkModel: ButtonModelProtocol, MoleculeModelProtocol, EnableableMode
         try container.encodeIfPresent(size, forKey: .size)
         try container.encode(shouldMaskRecordedView, forKey: .shouldMaskRecordedView)
     }
+    
+    public func isEqual(to model: any ModelComparisonProtocol) -> Bool {
+        guard let model = model as? Self else { return false }
+        return backgroundColor == model.backgroundColor
+        && title == model.title
+        && accessibilityText == model.accessibilityText
+        && accessibilityIdentifier == model.accessibilityIdentifier
+        && inverted == model.inverted
+        && enabled == model.enabled
+        && size == model.size
+        && shouldMaskRecordedView == model.shouldMaskRecordedView
+        && action.isEqual(to: model.action)
+    }
+    
+    public func isVisuallyEquivalent(to model: any MoleculeModelComparisonProtocol) -> Bool {
+        guard let model = model as? Self else { return false }
+        return backgroundColor == model.backgroundColor
+        && title == model.title
+        && accessibilityText == model.accessibilityText
+        && accessibilityIdentifier == model.accessibilityIdentifier
+        && inverted == model.inverted
+        && enabled == model.enabled
+        && size == model.size
+    }
 }
 
 extension LinkModel {

MVMCoreUI/Atomic/Atoms/Views/ArrowModel.swift

@@ -125,5 +125,19 @@ open class ArrowModel: MoleculeModelProtocol, EnableableModelProtocol {
         try container.encode(width, forKey: .width)
         try container.encode(height, forKey: .height)
         try container.encode(enabled, forKey: .enabled)
+        try container.encode(inverted, forKey: .inverted)
+    }
+    
+    public func isEqual(to model: any ModelComparisonProtocol) -> Bool {
+        guard let model = model as? Self else { return false }
+        return backgroundColor == model.backgroundColor
+        && disabledColor == model.disabledColor
+        && color == model.color
+        && degrees == model.degrees
+        && lineWidth == model.lineWidth
+        && width == model.width
+        && height == model.height
+        && enabled == model.enabled
+        && inverted == model.inverted
     }
 }

MVMCoreUI/Atomic/Atoms/Views/CarouselIndicator/CarouselIndicatorModel.swift

@@ -21,6 +21,8 @@ open class CarouselIndicatorModel: CarouselPagingModelProtocol, MoleculeModelPro
     public var id: String = UUID().uuidString
     public var backgroundColor: Color?
     public var moleculeName: String?
+
+    // Assigned and computed by parent.
     public var numberOfPages: Int = 0
     
     /// Sets the current Index to focus on.
@@ -49,7 +51,6 @@ open class CarouselIndicatorModel: CarouselPagingModelProtocol, MoleculeModelPro
         case moleculeName
         case backgroundColor
         case currentIndex
-        case numberOfPages
         case alwaysSendAction
         case animated
         case hidesForSinglePage
@@ -118,7 +119,6 @@ open class CarouselIndicatorModel: CarouselPagingModelProtocol, MoleculeModelPro
         try container.encode(id, forKey: .id)
         try container.encodeIfPresent(moleculeName, forKey: .moleculeName)
         try container.encodeIfPresent(backgroundColor, forKey: .backgroundColor)
-        try container.encode(numberOfPages, forKey: .numberOfPages)
         try container.encode(currentIndex, forKey: .currentIndex)
         try container.encode(alwaysSendAction, forKey: .alwaysSendAction)
         try container.encode(animated, forKey: .animated)
@@ -130,4 +130,31 @@ open class CarouselIndicatorModel: CarouselPagingModelProtocol, MoleculeModelPro
         try container.encode(indicatorColor, forKey: .indicatorColor)
         try container.encodeIfPresent(position, forKey: .position)
     }
+    
+    public func isEqual(to model: any ModelComparisonProtocol) -> Bool {
+        guard let model = model as? Self else { return false }
+        return backgroundColor == model.backgroundColor
+        && currentIndex == model.currentIndex
+        && alwaysSendAction == model.alwaysSendAction
+        && animated == model.animated
+        && hidesForSinglePage == model.hidesForSinglePage
+        && accessibilityHasSlidesInsteadOfPage == model.accessibilityHasSlidesInsteadOfPage
+        && enabled == model.enabled
+        && inverted == model.inverted
+        && disabledIndicatorColor == model.disabledIndicatorColor
+        && indicatorColor == model.indicatorColor
+        && position == model.position
+    }
+    
+    public func isVisuallyEquivalent(to model: any MoleculeModelComparisonProtocol) -> Bool {
+        guard let model = model as? Self else { return false }
+        return backgroundColor == model.backgroundColor
+        && animated == model.animated
+        && hidesForSinglePage == model.hidesForSinglePage
+        && accessibilityHasSlidesInsteadOfPage == model.accessibilityHasSlidesInsteadOfPage
+        && enabled == model.enabled
+        && inverted == model.inverted
+        && disabledIndicatorColor == model.disabledIndicatorColor
+        && indicatorColor == model.indicatorColor
+    }
 }

MVMCoreUI/Atomic/Atoms/Views/ImageViewModel.swift

@@ -61,4 +61,20 @@
         case shouldMaskRecordedView
         case allowServerParameters
     }
+    
+    public func isEqual(to model: any ModelComparisonProtocol) -> Bool {
+        guard let model = model as? Self else { return false }
+        return backgroundColor == model.backgroundColor
+        && image == model.image
+        && accessibilityText == model.accessibilityText
+        && fallbackImage == model.fallbackImage
+        && imageFormat == model.imageFormat
+        && width == model.width
+        && height == model.height
+        && contentMode == model.contentMode
+        && cornerRadius == model.cornerRadius
+        && clipsImage == model.clipsImage
+        && allowServerParameters == model.allowServerParameters
+        && shouldMaskRecordedView == model.shouldMaskRecordedView
+    }
 }

MVMCoreUI/Atomic/Atoms/Views/Label/LabelAttributeActionModel.swift

@@ -48,4 +48,9 @@ open class LabelAttributeActionModel: LabelAttributeModel {
         var container = encoder.container(keyedBy: CodingKeys.self)
         try container.encodeModel(action, forKey: .action)
     }
+    
+    public override func isEqual(to model: any ModelComparisonProtocol) -> Bool {
+        guard super.isEqual(to: model), let model = model as? Self else { return false }
+        return action.isEqual(to: model.action)
+    }
 }

MVMCoreUI/Atomic/Atoms/Views/Label/LabelAttributeColorModel.swift

@@ -43,4 +43,9 @@
         var container = encoder.container(keyedBy: CodingKeys.self)
         try container.encodeIfPresent(textColor, forKey: .textColor)
     }
+    
+    public override func isEqual(to model: any ModelComparisonProtocol) -> Bool {
+        guard super.isEqual(to: model), let model = model as? Self else { return false }
+        return textColor == model.textColor
+    }
 }

MVMCoreUI/Atomic/Atoms/Views/Label/LabelAttributeFontModel.swift

@@ -55,4 +55,11 @@
         try container.encodeIfPresent(name, forKey: .name)
         try container.encodeIfPresent(size, forKey: .size)
     }
+    
+    public override func isEqual(to model: any ModelComparisonProtocol) -> Bool {
+        guard super.isEqual(to: model), let model = model as? Self else { return false }
+        return style == model.style
+        && name == model.name
+        && size == model.size
+    }
 }

MVMCoreUI/Atomic/Atoms/Views/Label/LabelAttributeImageModel.swift

@@ -69,4 +69,12 @@ class LabelAttributeImageModel: LabelAttributeModel {
         try container.encodeIfPresent(URL, forKey: .URL)
         try container.encodeIfPresent(tintColor, forKey: .tintColor)
     }
+    
+    public override func isEqual(to model: any ModelComparisonProtocol) -> Bool {
+        guard super.isEqual(to: model), let model = model as? Self else { return false }
+        return URL == model.URL
+        && name == model.name
+        && size == model.size
+        && tintColor == model.tintColor
+    }
 }

MVMCoreUI/Atomic/Atoms/Views/Label/LabelAttributeModel.swift

@@ -7,7 +7,7 @@
 //
 
 
-@objcMembers open class LabelAttributeModel: ModelProtocol {
+@objcMembers open class LabelAttributeModel: ModelProtocol, ModelComparisonProtocol, MoleculeModelComparisonProtocol {
     //--------------------------------------------------
     // MARK: - Properties
     //--------------------------------------------------
@@ -75,4 +75,16 @@
         try container.encode(location, forKey: .location)
         try container.encode(length, forKey: .length)
     }
+    
+    public func isEqual(to model: any ModelComparisonProtocol) -> Bool {
+        guard let model = model as? Self else { return false }
+        return location == model.location
+        && length == model.length
+    }
+    
+    public func isVisuallyEquivalent(to model: any MoleculeModelComparisonProtocol) -> Bool {
+        guard let model = model as? Self else { return false }
+        return location == model.location
+        && length == model.length
+    }
 }

MVMCoreUI/Atomic/Atoms/Views/Label/LabelAttributeUnderlineModel.swift

@@ -66,6 +66,13 @@ import UIKit
         try container.encode(style, forKey: .style)
         try container.encodeIfPresent(pattern, forKey: .pattern)
     }
+    
+    public override func isEqual(to model: any ModelComparisonProtocol) -> Bool {
+        guard super.isEqual(to: model), let model = model as? Self else { return false }
+        return style == model.style
+        && color == model.color
+        && pattern == model.pattern
+    }
 }
 
 public enum UnderlineStyle: String, Codable {

MVMCoreUI/Atomic/Atoms/Views/Label/LabelModel.swift

@@ -132,6 +132,45 @@ import VDS
         try container.encodeIfPresent(shouldMaskRecordedView, forKey: .shouldMaskRecordedView)
         try container.encodeIfPresent(accessibilityTraits, forKey: .accessibilityTraits)
     }
+    
+    public func isEqual(to model: any ModelComparisonProtocol) -> Bool {
+        guard let model = model as? Self else { return false }
+        return backgroundColor == model.backgroundColor
+        && text == model.text
+        && textColor == model.textColor
+        && fontStyle == model.fontStyle
+        && fontName == model.fontName
+        && fontSize == model.fontSize
+        && textAlignment == model.textAlignment
+        && html == model.html
+        && hero == model.hero
+        && makeWholeViewClickable == model.makeWholeViewClickable
+        && numberOfLines == model.numberOfLines
+        && accessibilityText == model.accessibilityText
+        && accessibilityTraits == model.accessibilityTraits
+        && inverted == inverted
+        && shouldMaskRecordedView == model.shouldMaskRecordedView
+        && attributes.isEqual(to: model.attributes)
+    }
+    
+    public func isVisuallyEquivalent(to model: any MoleculeModelComparisonProtocol) -> Bool {
+        guard let model = model as? Self else { return false }
+        return backgroundColor == model.backgroundColor
+        && text == model.text
+        && textColor == model.textColor
+        && fontStyle == model.fontStyle
+        && fontName == model.fontName
+        && fontSize == model.fontSize
+        && textAlignment == model.textAlignment
+        && html == model.html
+        && hero == model.hero
+        && makeWholeViewClickable == model.makeWholeViewClickable
+        && numberOfLines == model.numberOfLines
+        && accessibilityText == model.accessibilityText
+        && accessibilityTraits == model.accessibilityTraits
+        && inverted == inverted
+        && attributes.isVisuallyEquivalent(to: model.attributes)
+    }
 }
 
 extension LabelModel {

MVMCoreUI/Atomic/Atoms/Views/LineModel.swift

@@ -129,4 +129,12 @@ public class LineModel: MoleculeModelProtocol, Invertable {
         try container.encodeIfPresent(frequency, forKey: .frequency)
         try container.encode(orientation == .vertical, forKey: .useVerticalLine)
     }
+    
+    public func isEqual(to model: any ModelComparisonProtocol) -> Bool {
+        guard let model = model as? Self else { return false }
+        return type == model.type
+        && inverted == model.inverted
+        && frequency == model.frequency
+        && orientation == model.orientation
+    }
 }

MVMCoreUI/Atomic/Atoms/Views/TileContainer.swift

@@ -136,4 +136,8 @@ open class TileContainer: VDS.TileContainer, VDSMoleculeViewProtocol{
 
 extension TileContainer: MVMCoreUIViewConstrainingProtocol {
     public func horizontalAlignment() -> UIStackView.Alignment { .leading }
+    
+    public func isClippable() -> Bool {
+        return false
+    }
 }

MVMCoreUI/Atomic/Atoms/Views/TileContainerModel.swift

@@ -25,7 +25,7 @@ open class TileContainerModel: TileContainerBaseModel<TileContainer.Padding, Til
         return [molecule]
     }
 
-    public func replaceChildMolecule(with molecule: MoleculeModelProtocol) throws -> Bool  {
+    public func replaceChildMolecule(with molecule: MoleculeModelProtocol) throws -> MoleculeModelProtocol? {
         return try replaceChildMolecule(at: &self.molecule, with: molecule)
     }
 

MVMCoreUI/Atomic/Atoms/Views/Tilelet.swift

@@ -134,3 +134,13 @@ open class Tilelet: VDS.Tilelet, VDSMoleculeViewProtocol{
         }
     }
 }
+
+extension Tilelet: MVMCoreUIViewConstrainingProtocol {
+    
+    // Investigate later.
+    //public func horizontalAlignment() -> UIStackView.Alignment { .leading }
+    
+    public func isClippable() -> Bool {
+        return false
+    }
+}

MVMCoreUI/Atomic/Extensions/ReadableDecodingErrors.swift

@@ -1,63 +0,0 @@
-//
-//  ReadableDecodingErrors.swift
-//  MVMCore
-//
-//  Created by Kyle Hedden on 10/5/23.
-//  Copyright © 2023 myverizon. All rights reserved.
-//
-
-import Foundation
-
-protocol HumanReadableDecodingErrorProtocol {
-    var readableDescription: String { get }
-}
-
-extension JSONError: HumanReadableDecodingErrorProtocol {
-    var readableDescription: String {
-        switch (self) {
-        case .other(let other):
-            if let other = other as? HumanReadableDecodingErrorProtocol {
-                return other.readableDescription
-            }
-            return description
-        default:
-            return description
-        }
-    }
-}
-
-extension ModelRegistry.Error: HumanReadableDecodingErrorProtocol {
-    var readableDescription: String {
-        switch (self) {
-        case .decoderErrorModelNotMapped(let identifier, let codingKey, let codingPath) where identifier != nil && codingKey != nil && codingPath != nil:
-            return "Model identifier \"\(identifier!)\" is not mapped for  \"\(codingKey!.stringValue)\" @ \(codingPath!.map { return $0.stringValue })"
-            
-        case .decoderErrorObjectNotPresent(let codingKey, let codingPath):
-            return "Required model \"\(codingKey.stringValue)\" was not found @ \(codingPath.map { return $0.stringValue })"
-            
-        default:
-            return "Registry error: \((self as NSError).localizedFailureReason ?? self.localizedDescription)"
-        }
-    }
-}
-
-extension DecodingError: HumanReadableDecodingErrorProtocol {
-    var readableDescription: String {
-        switch (self) {
-        case .keyNotFound(let codingKey, let context):
-            return "Required key \(codingKey.stringValue) was not found @ \(context.codingPath.map { return $0.stringValue })"
-            
-        case .valueNotFound(_, let context):
-            return "Value not found @ \(context.codingPath.map { return $0.stringValue })"
-            
-        case .typeMismatch(_, let context):
-            return "Value type mismatch @ \(context.codingPath.map { return $0.stringValue })"
-            
-        case .dataCorrupted(let context):
-            return "Data corrupted @ \(context.codingPath.map { return $0.stringValue })"
-            
-        @unknown default:
-            return (self as NSError).localizedFailureReason ?? self.localizedDescription
-        }
-    }
-}

MVMCoreUI/Atomic/Molecules/DesignedComponents/Headers/H1/HeadersH1ButtonModel.swift

@@ -21,9 +21,13 @@ public class HeadersH1ButtonModel: HeaderModel, MoleculeModelProtocol, ParentMol
         [titleLockup, buttons]
     }
     
-    public func replaceChildMolecule(with molecule: MoleculeModelProtocol) throws -> Bool {
+    public func replaceChildMolecule(with molecule: MoleculeModelProtocol) throws -> MoleculeModelProtocol? {
-        return try replaceChildMolecule(at: &titleLockup, with: molecule)
+        var replacedMolecule: MoleculeModelProtocol?
-        || replaceChildMolecule(at: &buttons, with: molecule)
+        if try replaceChildMolecule(at: &titleLockup, with: molecule, replaced: &replacedMolecule)
+            || replaceChildMolecule(at: &buttons, with: molecule, replaced: &replacedMolecule) {
+            return replacedMolecule
+        }
+        return nil
     }
     
     //--------------------------------------------------

MVMCoreUI/Atomic/Molecules/DesignedComponents/Headers/H1/HeadersH1LandingPageHeaderModel.swift

@@ -24,13 +24,17 @@ public class HeadersH1LandingPageHeaderModel: HeaderModel, MoleculeModelProtocol
         [headline, headline2, subHeadline, body, link, buttons]
     }
     
-    public func replaceChildMolecule(with molecule: MoleculeModelProtocol) throws -> Bool {
+    public func replaceChildMolecule(with molecule: MoleculeModelProtocol) throws -> MoleculeModelProtocol? {
-        return try replaceChildMolecule(at: &headline, with: molecule)
+        var replacedMolecule: MoleculeModelProtocol?
-        || replaceChildMolecule(at: &headline2, with: molecule)
+        if try replaceChildMolecule(at: &headline, with: molecule, replaced: &replacedMolecule)
-        || replaceChildMolecule(at: &subHeadline, with: molecule)
+        || replaceChildMolecule(at: &headline2, with: molecule, replaced: &replacedMolecule)
-        || replaceChildMolecule(at: &body, with: molecule)
+        || replaceChildMolecule(at: &subHeadline, with: molecule, replaced: &replacedMolecule)
-        || replaceChildMolecule(at: &link, with: molecule)
+        || replaceChildMolecule(at: &body, with: molecule, replaced: &replacedMolecule)
-        || replaceChildMolecule(at: &buttons, with: molecule)
+        || replaceChildMolecule(at: &link, with: molecule, replaced: &replacedMolecule)
+            || replaceChildMolecule(at: &buttons, with: molecule, replaced: &replacedMolecule) {
+            return replacedMolecule
+        }
+        return nil
     }
     
     //--------------------------------------------------

MVMCoreUI/Atomic/Molecules/DesignedComponents/Headers/H1/HeadersH1NoButtonsBodyTextModel.swift

@@ -19,7 +19,7 @@ public class HeadersH1NoButtonsBodyTextModel: HeaderModel, MoleculeModelProtocol
         [titleLockup]
     }
     
-    public func replaceChildMolecule(with molecule: MoleculeModelProtocol) throws -> Bool  {
+    public func replaceChildMolecule(with molecule: MoleculeModelProtocol) throws -> MoleculeModelProtocol? {
         return try replaceChildMolecule(at: &titleLockup, with: molecule)
     }
     

MVMCoreUI/Atomic/Molecules/DesignedComponents/Headers/H2/HeadersH2ButtonsModel.swift

@@ -23,9 +23,13 @@ public class HeadersH2ButtonsModel: HeaderModel, MoleculeModelProtocol, ParentMo
         [titleLockup, buttons]
     }
     
-    public func replaceChildMolecule(with molecule: MoleculeModelProtocol) throws -> Bool  {
+    public func replaceChildMolecule(with molecule: MoleculeModelProtocol) throws -> MoleculeModelProtocol? {
-        return try replaceChildMolecule(at: &titleLockup, with: molecule)
+        var replacedMolecule: MoleculeModelProtocol?
-        || replaceChildMolecule(at: &buttons, with: molecule)
+        if try replaceChildMolecule(at: &titleLockup, with: molecule, replaced: &replacedMolecule)
+            || replaceChildMolecule(at: &buttons, with: molecule, replaced: &replacedMolecule) {
+            return replacedMolecule
+        }
+        return nil
     }
     
     //--------------------------------------------------

MVMCoreUI/Atomic/Molecules/DesignedComponents/Headers/H2/HeadersH2CaretLinkModel.swift

@@ -20,9 +20,13 @@ public class HeadersH2CaretLinkModel: HeaderModel, MoleculeModelProtocol, Parent
         [titleLockup, caretLink]
     }
     
-    public func replaceChildMolecule(with molecule: MoleculeModelProtocol) throws -> Bool  {
+    public func replaceChildMolecule(with molecule: MoleculeModelProtocol) throws -> MoleculeModelProtocol? {
-        return try replaceChildMolecule(at: &titleLockup, with: molecule)
+        var replacedMolecule: MoleculeModelProtocol?
-        || replaceChildMolecule(at: &caretLink, with: molecule)
+        if try replaceChildMolecule(at: &titleLockup, with: molecule, replaced: &replacedMolecule)
+            || replaceChildMolecule(at: &caretLink, with: molecule, replaced: &replacedMolecule) {
+            return replacedMolecule
+        }
+        return nil
     }
     
     //--------------------------------------------------

MVMCoreUI/Atomic/Molecules/DesignedComponents/Headers/H2/HeadersH2LinkModel.swift

@@ -8,7 +8,7 @@
 
 import Foundation
 
-public class HeadersH2LinkModel: HeaderModel, MoleculeModelProtocol, ParentMoleculeModelProtocol {
+public class HeadersH2LinkModel: HeaderModel, ParentMoleculeModelProtocol {
     //--------------------------------------------------
     // MARK: - Properties
     //--------------------------------------------------
@@ -22,9 +22,13 @@ public class HeadersH2LinkModel: HeaderModel, MoleculeModelProtocol, ParentMolec
         [titleLockup, link]
     }
     
-    public func replaceChildMolecule(with molecule: MoleculeModelProtocol) throws -> Bool  {
+    public func replaceChildMolecule(with molecule: MoleculeModelProtocol) throws -> MoleculeModelProtocol? {
-        return try replaceChildMolecule(at: &titleLockup, with: molecule)
+        var replacedMolecule: MoleculeModelProtocol?
-        || replaceChildMolecule(at: &link, with: molecule)
+        if try replaceChildMolecule(at: &titleLockup, with: molecule, replaced: &replacedMolecule)
+            || replaceChildMolecule(at: &link, with: molecule, replaced: &replacedMolecule) {
+            return replacedMolecule
+        }
+        return nil
     }
     
     //--------------------------------------------------

MVMCoreUI/Atomic/Molecules/DesignedComponents/Headers/H2/HeadersH2NoButtonsBodyTextModel.swift

@@ -22,7 +22,7 @@ public class HeadersH2NoButtonsBodyTextModel: HeaderModel, MoleculeModelProtocol
         [titleLockup]
     }
     
-    public func replaceChildMolecule(with molecule: MoleculeModelProtocol) throws -> Bool  {
+    public func replaceChildMolecule(with molecule: MoleculeModelProtocol) throws -> MoleculeModelProtocol? {
         return try replaceChildMolecule(at: &titleLockup, with: molecule)
     }
     

MVMCoreUI/Atomic/Molecules/DesignedComponents/Headers/H2/HeadersH2PricingTwoRowsModel.swift

@@ -25,15 +25,18 @@ public class HeadersH2PricingTwoRowsModel: HeaderModel, MoleculeModelProtocol, P
         [headline, body, subBody, body2, subBody2, body3, subBody3].compactMap({$0})
     }
     
-    public func replaceChildMolecule(with molecule: MoleculeModelProtocol) throws -> Bool  {
+    public func replaceChildMolecule(with molecule: MoleculeModelProtocol) throws -> MoleculeModelProtocol? {
-        return try replaceChildMolecule(at: &headline, with: molecule)
+        var replacedMolecule: MoleculeModelProtocol?
-        || replaceChildMolecule(at: &body, with: molecule)
+        if try replaceChildMolecule(at: &headline, with: molecule, replaced: &replacedMolecule)
-        || replaceChildMolecule(at: &subBody, with: molecule)
+            || replaceChildMolecule(at: &body, with: molecule, replaced: &replacedMolecule)
-        || replaceChildMolecule(at: &body2, with: molecule)
+            || replaceChildMolecule(at: &subBody, with: molecule, replaced: &replacedMolecule)
-        || replaceChildMolecule(at: &body2, with: molecule)
+            || replaceChildMolecule(at: &body2, with: molecule, replaced: &replacedMolecule)
-        || replaceChildMolecule(at: &subBody2, with: molecule)
+            || replaceChildMolecule(at: &subBody2, with: molecule, replaced: &replacedMolecule)
-        || replaceChildMolecule(at: &body3, with: molecule)
+            || replaceChildMolecule(at: &body3, with: molecule, replaced: &replacedMolecule)
-        || replaceChildMolecule(at: &subBody3, with: molecule)
+            || replaceChildMolecule(at: &subBody3, with: molecule, replaced: &replacedMolecule) {
+            return replacedMolecule
+        }
+        return nil
     }
     
     //--------------------------------------------------

MVMCoreUI/Atomic/Molecules/DesignedComponents/Headers/H2/HeadersH2TinyButtonModel.swift

@@ -23,9 +23,13 @@ public class HeadersH2TinyButtonModel: HeaderModel, MoleculeModelProtocol, Paren
         [titleLockup, button]
     }
     
-    public func replaceChildMolecule(with molecule: MoleculeModelProtocol) throws -> Bool  {
+    public func replaceChildMolecule(with molecule: MoleculeModelProtocol) throws -> MoleculeModelProtocol? {
-        return try replaceChildMolecule(at: &titleLockup, with: molecule)
+        var replacedMolecule: MoleculeModelProtocol?
-        || replaceChildMolecule(at: &button, with: molecule)
+        if try replaceChildMolecule(at: &titleLockup, with: molecule, replaced: &replacedMolecule)
+            || replaceChildMolecule(at: &button, with: molecule, replaced: &replacedMolecule) {
+            return replacedMolecule
+        }
+        return nil
     }
     
     //--------------------------------------------------

MVMCoreUI/Atomic/Molecules/DesignedComponents/List/LeftVariable/ListLeftVariableCheckboxBodyTextModel.swift

@@ -20,9 +20,13 @@ open class ListLeftVariableCheckboxBodyTextModel: ListItemModel, MoleculeModelPr
          [checkbox, headlineBody]
     }
     
-    public func replaceChildMolecule(with molecule: MoleculeModelProtocol) throws -> Bool  {
+    public func replaceChildMolecule(with molecule: MoleculeModelProtocol) throws -> MoleculeModelProtocol? {
-        return try replaceChildMolecule(at: &checkbox, with: molecule)
+        var replacedMolecule: MoleculeModelProtocol?
-        || replaceChildMolecule(at: &headlineBody, with: molecule)
+        if try replaceChildMolecule(at: &checkbox, with: molecule, replaced: &replacedMolecule)
+            || replaceChildMolecule(at: &headlineBody, with: molecule, replaced: &replacedMolecule) {
+            return replacedMolecule
+        }
+        return nil
     }
     
     //--------------------------------------------------

MVMCoreUI/Atomic/Molecules/DesignedComponents/List/LeftVariable/ListLeftVariableIconAllTextLinksModel.swift

@@ -20,9 +20,13 @@ public class ListLeftVariableIconAllTextLinksModel: ListItemModel, MoleculeModel
         return [image, eyebrowHeadlineBodyLink]
     }
     
-    public func replaceChildMolecule(with molecule: MoleculeModelProtocol) throws -> Bool  {
+    public func replaceChildMolecule(with molecule: MoleculeModelProtocol) throws -> MoleculeModelProtocol? {
-        return try replaceChildMolecule(at: &image, with: molecule)
+        var replacedMolecule: MoleculeModelProtocol?
-        || replaceChildMolecule(at: &eyebrowHeadlineBodyLink, with: molecule)
+        if try replaceChildMolecule(at: &image, with: molecule, replaced: &replacedMolecule)
+            || replaceChildMolecule(at: &eyebrowHeadlineBodyLink, with: molecule, replaced: &replacedMolecule) {
+            return replacedMolecule
+        }
+        return nil
     }
     
     //--------------------------------------------------

MVMCoreUI/Atomic/Molecules/DesignedComponents/List/LeftVariable/ListLeftVariableIconWithRightCaretAllTextLinksModel.swift

@@ -21,10 +21,14 @@ public class ListLeftVariableIconWithRightCaretAllTextLinksModel: ListItemModel,
         return [image, eyebrowHeadlineBodyLink, rightLabel]
     }
     
-    public func replaceChildMolecule(with molecule: MoleculeModelProtocol) throws -> Bool  {
+    public func replaceChildMolecule(with molecule: MoleculeModelProtocol) throws -> MoleculeModelProtocol? {
-        return try replaceChildMolecule(at: &image, with: molecule)
+        var replacedMolecule: MoleculeModelProtocol?
-        || replaceChildMolecule(at: &eyebrowHeadlineBodyLink, with: molecule)
+        if try replaceChildMolecule(at: &image, with: molecule, replaced: &replacedMolecule)
-        || replaceChildMolecule(at: &rightLabel, with: molecule)
+            || replaceChildMolecule(at: &eyebrowHeadlineBodyLink, with: molecule, replaced: &replacedMolecule)
+            || replaceChildMolecule(at: &rightLabel, with: molecule, replaced: &replacedMolecule) {
+            return replacedMolecule
+        }
+        return nil
     }
     
     //-----------------------------------------------------

MVMCoreUI/Atomic/Molecules/DesignedComponents/List/LeftVariable/ListLeftVariableIconWithRightCaretBodyTextModel.swift

@@ -21,10 +21,14 @@ public class ListLeftVariableIconWithRightCaretBodyTextModel: ListItemModel, Par
         [image, headlineBody, rightLabel]
     }
     
-    public func replaceChildMolecule(with molecule: MoleculeModelProtocol) throws -> Bool  {
+    public func replaceChildMolecule(with molecule: MoleculeModelProtocol) throws -> MoleculeModelProtocol? {
-        return try replaceChildMolecule(at: &image, with: molecule)
+        var replacedMolecule: MoleculeModelProtocol?
-        || replaceChildMolecule(at: &headlineBody, with: molecule)
+        if try replaceChildMolecule(at: &image, with: molecule, replaced: &replacedMolecule)
-        || replaceChildMolecule(at: &rightLabel, with: molecule)
+            || replaceChildMolecule(at: &headlineBody, with: molecule, replaced: &replacedMolecule)
+            || replaceChildMolecule(at: &rightLabel, with: molecule, replaced: &replacedMolecule) {
+            return replacedMolecule
+        }
+        return nil
     }
     
     //-----------------------------------------------------

MVMCoreUI/Atomic/Molecules/DesignedComponents/List/LeftVariable/ListLeftVariableIconWithRightCaretModel.swift

@@ -21,10 +21,14 @@ public class ListLeftVariableIconWithRightCaretModel: ListItemModel, ParentMolec
         return [image, leftLabel, rightLabel]
     }
     
-    public func replaceChildMolecule(with molecule: MoleculeModelProtocol) throws -> Bool  {
+    public func replaceChildMolecule(with molecule: MoleculeModelProtocol) throws -> MoleculeModelProtocol? {
-        return try replaceChildMolecule(at: &image, with: molecule)
+        var replacedMolecule: MoleculeModelProtocol?
-        || replaceChildMolecule(at: &leftLabel, with: molecule)
+        if try replaceChildMolecule(at: &image, with: molecule, replaced: &replacedMolecule)
-        || replaceChildMolecule(at: &rightLabel, with: molecule)
+            || replaceChildMolecule(at: &leftLabel, with: molecule, replaced: &replacedMolecule)
+            || replaceChildMolecule(at: &rightLabel, with: molecule, replaced: &replacedMolecule) {
+            return replacedMolecule
+        }
+        return nil
     }
     
     //-----------------------------------------------------

MVMCoreUI/Atomic/Molecules/DesignedComponents/List/LeftVariable/ListLeftVariableRadioButtonBodyTextModel.swift

@@ -20,9 +20,13 @@ open class ListLeftVariableRadioButtonBodyTextModel: ListItemModel, ParentMolecu
         [radioButton, headlineBody]
     }
     
-    public func replaceChildMolecule(with replacementMolecule: MoleculeModelProtocol) throws -> Bool {
+    public func replaceChildMolecule(with replacementMolecule: MoleculeModelProtocol) throws -> MoleculeModelProtocol? {
-        return try replaceChildMolecule(at: &radioButton, with: replacementMolecule)
+        var replacedMolecule: MoleculeModelProtocol?
-        || replaceChildMolecule(at: &headlineBody, with: replacementMolecule)
+        if try replaceChildMolecule(at: &radioButton, with: replacementMolecule, replaced: &replacedMolecule)
+            || replaceChildMolecule(at: &headlineBody, with: replacementMolecule, replaced: &replacedMolecule) {
+            return replacedMolecule
+        }
+        return nil
     }
     
     //-----------------------------------------------------

MVMCoreUI/Atomic/Molecules/DesignedComponents/List/OneColumn/ListOneColumnFullWidthTextBodyTextModel.swift

@@ -39,7 +39,7 @@ public class ListOneColumnFullWidthTextBodyTextModel: ListItemModel, MoleculeMod
         return [headlineBody]
     }
     
-    public func replaceChildMolecule(with molecule: MoleculeModelProtocol) throws -> Bool  {
+    public func replaceChildMolecule(with molecule: MoleculeModelProtocol) throws -> MoleculeModelProtocol? {
         return try replaceChildMolecule(at: &headlineBody, with: molecule)
     }
     

MVMCoreUI/Atomic/Molecules/DesignedComponents/List/RightVariable/ListRightVariableButtonAllTextAndLinksModel.swift

@@ -40,9 +40,13 @@ public class ListRightVariableButtonAllTextAndLinksModel: ListItemModel, Molecul
         return [button, eyebrowHeadlineBodyLink]
     }
     
-    public func replaceChildMolecule(with molecule: MoleculeModelProtocol) throws -> Bool  {
+    public func replaceChildMolecule(with molecule: MoleculeModelProtocol) throws -> MoleculeModelProtocol? {
-        return try replaceChildMolecule(at: &button, with: molecule)
+        var replacedMolecule: MoleculeModelProtocol?
-        || replaceChildMolecule(at: &eyebrowHeadlineBodyLink, with: molecule)
+        if try replaceChildMolecule(at: &button, with: molecule, replaced: &replacedMolecule)
+            || replaceChildMolecule(at: &eyebrowHeadlineBodyLink, with: molecule, replaced: &replacedMolecule) {
+            return replacedMolecule
+        }
+        return nil
     }
     
     //--------------------------------------------------

MVMCoreUI/Atomic/Molecules/DesignedComponents/List/RightVariable/ListRightVariableRightCaretAlltextAndLinksModel.swift

@@ -20,9 +20,13 @@ public class ListRightVariableRightCaretAllTextAndLinksModel: ListItemModel, Par
         [rightLabel, eyebrowHeadlineBodyLink]
     }
     
-    public func replaceChildMolecule(with molecule: MoleculeModelProtocol) throws -> Bool  {
+    public func replaceChildMolecule(with molecule: MoleculeModelProtocol) throws -> MoleculeModelProtocol? {
-        return try replaceChildMolecule(at: &rightLabel, with: molecule)
+        var replacedMolecule: MoleculeModelProtocol?
-        || replaceChildMolecule(at: &eyebrowHeadlineBodyLink, with: molecule)
+        if try replaceChildMolecule(at: &rightLabel, with: molecule, replaced: &replacedMolecule)
+            || replaceChildMolecule(at: &eyebrowHeadlineBodyLink, with: molecule, replaced: &replacedMolecule) {
+            return replacedMolecule
+        }
+        return nil
     }
     
     //-----------------------------------------------------

MVMCoreUI/Atomic/Molecules/DesignedComponents/LockUps/TitleLockupModel.swift

@@ -9,7 +9,7 @@
 import VDSCoreTokens
 import VDS
 
-public class TitleLockupModel: MoleculeModelProtocol, ParentMoleculeModelProtocol {
+public class TitleLockupModel: ParentMoleculeModelProtocol {
     
     //--------------------------------------------------
     // MARK: - Properties
@@ -36,10 +36,26 @@ public class TitleLockupModel: MoleculeModelProtocol, ParentMoleculeModelProtoco
         [eyebrow, title, subTitle].compactMap { (molecule: MoleculeModelProtocol?) in molecule }
     }
     
-    public func replaceChildMolecule(with molecule: MoleculeModelProtocol) throws -> Bool  {
+    public func replaceChildMolecule(with molecule: MoleculeModelProtocol) throws -> MoleculeModelProtocol? {
-        return try replaceChildMolecule(at: &eyebrow, with: molecule)
+        var replacedMolecule: MoleculeModelProtocol?
-        || replaceChildMolecule(at: &title, with: molecule)
+        if try replaceChildMolecule(at: &eyebrow, with: molecule, replaced: &replacedMolecule)
-        || replaceChildMolecule(at: &subTitle, with: molecule)
+            || replaceChildMolecule(at: &title, with: molecule, replaced: &replacedMolecule)
+            || replaceChildMolecule(at: &subTitle, with: molecule, replaced: &replacedMolecule) {
+            return replacedMolecule
+        }
+        return nil
+    }
+    
+    public func isEqual(to model: any ModelComparisonProtocol) -> Bool {
+        guard let model = model as? Self else { return false }
+        return textAlignment == model.textAlignment
+        && alignment == model.alignment
+        && titleColor == model.titleColor
+        && subTitleColor == model.subTitleColor
+        && inverted == model.inverted
+        && backgroundColor == model.backgroundColor
+        && eyebrow.matchExistence(with: model.eyebrow)
+        && subTitle.matchExistence(with: model.subTitle)
     }
     
     //--------------------------------------------------

MVMCoreUI/Atomic/Molecules/DesignedComponents/SectionDividers/OneColumn/ListOneColumnFullWidthTextDividerSubsectionModel.swift

@@ -22,9 +22,13 @@ public class ListOneColumnFullWidthTextDividerSubsectionModel: ListItemModel, Mo
         [headline, body].compactMap({$0})
     }
     
-    public func replaceChildMolecule(with molecule: MoleculeModelProtocol) throws -> Bool  {
+    public func replaceChildMolecule(with molecule: MoleculeModelProtocol) throws -> MoleculeModelProtocol? {
-        return try replaceChildMolecule(at: &headline, with: molecule)
+        var replacedMolecule: MoleculeModelProtocol?
-        || replaceChildMolecule(at: &body, with: molecule)
+        if try replaceChildMolecule(at: &headline, with: molecule, replaced: &replacedMolecule)
+            || replaceChildMolecule(at: &body, with: molecule, replaced: &replacedMolecule) {
+            return replacedMolecule
+        }
+        return nil
     }
     
     //--------------------------------------------------

MVMCoreUI/Atomic/Molecules/DesignedComponents/SectionDividers/OneColumn/ListOneColumnTextWithWhitespaceDividerShortModel.swift

@@ -22,9 +22,13 @@ public class ListOneColumnTextWithWhitespaceDividerShortModel: ListItemModel, Mo
         [headline, body].compactMap({$0})
     }
     
-    public func replaceChildMolecule(with molecule: MoleculeModelProtocol) throws -> Bool  {
+    public func replaceChildMolecule(with molecule: MoleculeModelProtocol) throws -> MoleculeModelProtocol? {
-        return try replaceChildMolecule(at: &headline, with: molecule)
+        var replacedMolecule: MoleculeModelProtocol?
-        || replaceChildMolecule(at: &body, with: molecule)
+        if try replaceChildMolecule(at: &headline, with: molecule, replaced: &replacedMolecule)
+            || replaceChildMolecule(at: &body, with: molecule, replaced: &replacedMolecule) {
+            return replacedMolecule
+        }
+        return nil
     }
     
     //--------------------------------------------------

MVMCoreUI/Atomic/Molecules/DesignedComponents/SectionDividers/OneColumn/ListOneColumnTextWithWhitespaceDividerTallModel.swift

@@ -22,9 +22,13 @@ public class ListOneColumnTextWithWhitespaceDividerTallModel: ListItemModel, Mol
         [headline, body].compactMap({$0})
     }
     
-    public func replaceChildMolecule(with molecule: MoleculeModelProtocol) throws -> Bool  {
+    public func replaceChildMolecule(with molecule: MoleculeModelProtocol) throws -> MoleculeModelProtocol? {
-        return try replaceChildMolecule(at: &headline, with: molecule)
+        var replacedMolecule: MoleculeModelProtocol?
-        || replaceChildMolecule(at: &body, with: molecule)
+        if try replaceChildMolecule(at: &headline, with: molecule, replaced: &replacedMolecule)
+            || replaceChildMolecule(at: &body, with: molecule, replaced: &replacedMolecule) {
+            return replacedMolecule
+        }
+        return nil
     }
     
     //--------------------------------------------------

MVMCoreUI/Atomic/Molecules/HeadersAndFooters/MoleculeSectionHeaderModel.swift

@@ -68,4 +68,9 @@
         var container = encoder.container(keyedBy: CodingKeys.self)
         try container.encode(line, forKey: .line)
     }
+    
+    public override func isEqual(to model: any ModelComparisonProtocol) -> Bool {
+        guard let model = model as? Self else { return false }
+        return line.matchExistence(with: model.line)
+    }
 }

MVMCoreUI/Atomic/Molecules/HorizontalCombinationViews/TabBarModel.swift

@@ -106,9 +106,30 @@ open class TabBarModel: MoleculeModelProtocol {
         try container.encode(selectedTab, forKey: .selectedTab)
         try container.encodeIfPresent(style, forKey: .style)
     }
+    
+    public func isEqual(to model: any ModelComparisonProtocol) -> Bool {
+        guard let model = model as? Self else { return false }
+        return backgroundColor == model.backgroundColor
+        && selectedColor == model.selectedColor
+        && selectedTab == model.selectedTab
+        && unSelectedColor == model.unSelectedColor
+        && style == model.style
+        && tabs == model.tabs
+    }
+    
+    public func isVisuallyEquivalent(to model: any MoleculeModelComparisonProtocol) -> Bool {
+        guard let model = model as? Self else { return false }
+        return backgroundColor == model.backgroundColor
+        && selectedColor == model.selectedColor
+        && selectedTab == model.selectedTab
+        && unSelectedColor == model.unSelectedColor
+        && style == model.style
+        && tabs.isVisuallyEquivalent(to: model.tabs)
+    }
 }
 
-open class TabBarItemModel: Codable {
+open class TabBarItemModel: Codable, Equatable, MoleculeModelComparisonProtocol {
+    
     open var title: String?
     open var image: String
     open var action: ActionModelProtocol
@@ -142,4 +163,18 @@ open class TabBarItemModel: Codable {
         try container.encodeModel(action, forKey: .action)
         try container.encodeIfPresent(accessibilityText, forKey: .accessibilityText)
     }
+    
+    public static func == (lhs: TabBarItemModel, rhs: TabBarItemModel) -> Bool {
+        return lhs.title == rhs.title
+        && lhs.image == rhs.image
+        && lhs.accessibilityText == rhs.accessibilityText
+        && lhs.action.isEqual(to: rhs.action)
+    }
+    
+    public func isVisuallyEquivalent(to model: any MoleculeModelComparisonProtocol) -> Bool {
+        guard let model = model as? Self else { return false }
+        return image == model.image
+        && accessibilityText == model.accessibilityText
+        && title == model.title
+    }
 }

MVMCoreUI/Atomic/Molecules/HorizontalCombinationViews/TabsModel.swift

@@ -105,11 +105,39 @@ open class TabsModel: MoleculeModelProtocol {
         try container.encode(borderLine, forKey: .borderLine)
         try container.encodeIfPresent(minWidth, forKey: .minWidth)
     }
+    
+    public func isEqual(to model: any ModelComparisonProtocol) -> Bool {
+        guard let model = model as? Self else { return false }
+        return backgroundColor == model.backgroundColor
+        && style == model.style
+        && orientation == model.orientation
+        && indicatorPosition == model.indicatorPosition
+        && overflow == model.overflow
+        && fillContainer == model.fillContainer
+        && size == model.size
+        && borderLine == model.borderLine
+        && minWidth == model.minWidth
+        && selectedIndex == model.selectedIndex
+        && tabs == model.tabs
+    }
+    
+    public func isVisuallyEquivalent(to model: any MoleculeModelComparisonProtocol) -> Bool {
+        guard let model = model as? Self else { return false }
+        return backgroundColor == model.backgroundColor
+        && style == model.style
+        && orientation == model.orientation
+        && indicatorPosition == model.indicatorPosition
+        && overflow == model.overflow
+        && fillContainer == model.fillContainer
+        && size == model.size
+        && borderLine == model.borderLine
+        && minWidth == model.minWidth
+        //&& selectedIndex == model.selectedIndex  // Selected index could have been either reset locally or by server. For now ignore.
+        && tabs.isVisuallyEquivalent(to: model.tabs)
+    }
 }
 
-
+open class TabItemModel: Codable, Equatable, MoleculeModelComparisonProtocol {
-
-open class TabItemModel: Codable {
     open var label: LabelModel
     open var action: ActionModelProtocol?
     public var analyticsData: JSONValueDictionary?
@@ -150,4 +178,14 @@ open class TabItemModel: Codable {
         try container.encodeModelIfPresent(action, forKey: .action)
         try container.encodeIfPresent(analyticsData, forKey: .analyticsData)
     }
+    
+    public static func == (lhs: TabItemModel, rhs: TabItemModel) -> Bool {
+        return lhs.label.isEqual(to: rhs.label)
+        && lhs.action.isEqual(to: rhs.action)
+    }
+    
+    public func isVisuallyEquivalent(to model: any MoleculeModelComparisonProtocol) -> Bool {
+        guard let model = model as? Self else { return false }
+        return label.isVisuallyEquivalent(to: model.label)
+    }
 }

MVMCoreUI/Atomic/Molecules/HorizontalCombinationViews/TwoButtonViewModel.swift

@@ -23,9 +23,13 @@ public class TwoButtonViewModel: ParentMoleculeModelProtocol {
     
     public var children: [MoleculeModelProtocol] { [primaryButton, secondaryButton].compactMap { $0 } }
     
-    public func replaceChildMolecule(with molecule: MoleculeModelProtocol) throws -> Bool  {
+    public func replaceChildMolecule(with molecule: MoleculeModelProtocol) throws -> MoleculeModelProtocol? {
-        return try replaceChildMolecule(at: &primaryButton, with: molecule)
+        var replacedMolecule: MoleculeModelProtocol?
-        || replaceChildMolecule(at: &secondaryButton, with: molecule)
+        if try replaceChildMolecule(at: &primaryButton, with: molecule, replaced: &replacedMolecule)
+            || replaceChildMolecule(at: &secondaryButton, with: molecule, replaced: &replacedMolecule) {
+            return replacedMolecule
+        }
+        return nil
     }
     
     //--------------------------------------------------
@@ -82,4 +86,12 @@ public class TwoButtonViewModel: ParentMoleculeModelProtocol {
         try container.encodeIfPresent(secondaryButton, forKey: .secondaryButton)
         try container.encodeIfPresent(fillContainer, forKey: .fillContainer)
     }
+    
+    public func isEqual(to model: any ModelComparisonProtocol) -> Bool {
+        guard let model = model as? Self else { return false }
+        return backgroundColor == model.backgroundColor
+        && fillContainer == model.fillContainer
+        && primaryButton.matchExistence(with: model.primaryButton)
+        && secondaryButton.matchExistence(with: model.secondaryButton)
+    }
 }

MVMCoreUI/Atomic/Molecules/Items/AccordionListItemModel.swift

@@ -80,6 +80,14 @@ class AccordionListItemModel: MoleculeListItemModel {
         try container.encodeModelIfPresent(expandAction, forKey: .expandAction)
         try container.encodeModelIfPresent(collapseAction, forKey: .collapseAction)
     }
+    
+    override func isEqual(to model: any ModelComparisonProtocol) -> Bool {
+        guard super.isEqual(to: model), let model = model as? Self else { return false }
+        return selected == model.selected
+        && hideLineWhenExpanded == model.hideLineWhenExpanded
+        && expandAction.matchExistence(with: model.expandAction)
+        && collapseAction.matchExistence(with: model.collapseAction)
+    }
 }
 
 extension AccordionListItemModel: PageBehaviorProtocolRequirer {

MVMCoreUI/Atomic/Molecules/Items/CarouselItem.swift

@@ -7,6 +7,7 @@
 //
 
 import Foundation
+import VDS
 
 open class CarouselItem: MoleculeCollectionViewCell, CarouselItemProtocol {
     
@@ -17,12 +18,14 @@ open class CarouselItem: MoleculeCollectionViewCell, CarouselItemProtocol {
     
     open override func addMolecule(_ molecule: MoleculeViewProtocol) {
         super.addMolecule(molecule)
+        
+        clipsToBounds = (molecule as? MVMCoreUIViewConstrainingProtocol)?.isClippable?() ?? true
+        
         contentView.sendSubviewToBack(molecule)
     }
     
     open override func setupView() {
         super.setupView()
-        clipsToBounds = false
         
         // Covers the card when peaking.
         peakingCover.backgroundColor = .white

MVMCoreUI/Atomic/Molecules/Items/CarouselItemModel.swift

@@ -85,8 +85,27 @@
         try container.encodeIfPresent(peakingUI, forKey: .peakingUI)
         try container.encodeIfPresent(peakingArrowColor, forKey: .peakingArrowColor)
         try container.encodeIfPresent(analyticsData, forKey: .analyticsData)
+        try container.encodeIfPresent(fieldKey, forKey: .fieldKey)
         try container.encodeIfPresent(fieldValue, forKey: .fieldValue)
         try container.encode(enabled, forKey: .enabled)
         try container.encode(readOnly, forKey: .readOnly)
     }
+    
+    public override func isEqual(to model: any ModelComparisonProtocol) -> Bool {
+        guard super.isEqual(to: model), let model = model as? Self else { return false }
+        return peakingUI ==  model.peakingUI
+        && peakingArrowColor == model.peakingArrowColor
+        && analyticsData == model.analyticsData
+        && fieldValue == model.fieldValue
+        && enabled == model.enabled
+        && readOnly == model.readOnly
+    }
+    
+    public override func isVisuallyEquivalent(to model: any MoleculeModelComparisonProtocol) -> Bool {
+        guard super.isVisuallyEquivalent(to: model), let model = model as? Self else { return false }
+        return peakingUI ==  model.peakingUI
+        && peakingArrowColor == model.peakingArrowColor
+        && enabled == model.enabled
+        && readOnly == model.readOnly
+    }
 }

MVMCoreUI/Atomic/Molecules/Items/ListItemModel.swift

@@ -8,7 +8,8 @@
 //  A base class that has common list item boilerplate model stuffs.
 import MVMCore
 
-@objcMembers open class ListItemModel: ContainerModel, ListItemModelProtocol {
+@objcMembers open class ListItemModel: ContainerModel, ListItemModelProtocol, MoleculeModelComparisonProtocol {
+    
     //--------------------------------------------------
     // MARK: - Properties
     //--------------------------------------------------
@@ -22,6 +23,7 @@ import MVMCore
     public var accessibilityTraits: UIAccessibilityTraits?
     public var accessibilityValue: String?
     public var accessibilityText: String?
+    
     //--------------------------------------------------
     // MARK: - Keys
     //--------------------------------------------------
@@ -128,4 +130,29 @@ import MVMCore
         try container.encodeIfPresent(accessibilityValue, forKey: .accessibilityValue)
         try container.encodeIfPresent(accessibilityText, forKey: .accessibilityText)
     }
+    
+    public override func isEqual(to model: any ModelComparisonProtocol) -> Bool {
+        guard super.isEqual(to: model), let model = model as? Self else { return false }
+        return backgroundColor == model.backgroundColor
+        && hideArrow == model.hideArrow
+        && style == model.style
+        && gone == model.gone
+        && accessibilityText == model.accessibilityText
+        && accessibilityValue == model.accessibilityValue
+        && accessibilityTraits == model.accessibilityTraits
+        && line.matchExistence(with: model.line)
+        && action.isEqual(to: model.action)
+    }
+    
+    public func isVisuallyEquivalent(to model: any MoleculeModelComparisonProtocol) -> Bool {
+        guard let model = model as? Self else { return false }
+        return backgroundColor == model.backgroundColor
+        && hideArrow == model.hideArrow
+        && style == model.style
+        && gone == model.gone
+        && accessibilityText == model.accessibilityText
+        && accessibilityValue == model.accessibilityValue
+        && accessibilityTraits == model.accessibilityTraits
+        && line.matchExistence(with: model.line)
+    }
 }

MVMCoreUI/Atomic/Molecules/Items/MoleculeCollectionItemModel.swift

@@ -73,4 +73,15 @@
         try container.encodeIfPresent(border, forKey: .border)
         try super.encode(to: encoder)
     }
+    
+    public override func isEqual(to model: any ModelComparisonProtocol) -> Bool {
+        guard super.isEqual(to: model), let model = model as? Self else { return false }
+        return border == border
+        && action.isEqual(to: model.action)
+    }
+    
+    public override func isVisuallyEquivalent(to model: any MoleculeModelComparisonProtocol) -> Bool {
+        guard super.isVisuallyEquivalent(to: model), let model = model as? Self else { return false }
+        return border == model.border
+    }
 }

MVMCoreUI/Atomic/Molecules/Items/MoleculeStackItemModel.swift

@@ -58,4 +58,11 @@
         try container.encodeIfPresent(percent, forKey: .percent)
         try container.encode(gone, forKey: .gone)
     }
+    
+    public override func isEqual(to model: any ModelComparisonProtocol) -> Bool {
+        guard super.isEqual(to: model), let model = model as? Self else { return false }
+        return spacing == model.spacing
+        && percent == model.percent
+        && gone == model.gone
+    }
 }

MVMCoreUI/Atomic/Molecules/Items/MoleculeTableViewCell.swift

@@ -30,7 +30,7 @@ import UIKit
     }
 
     public override class func nameForReuse(with model: MoleculeModelProtocol, _ delegateObject: MVMCoreUIDelegateObject?) -> String? {
-        MoleculeContainer.nameForReuse(with: model, delegateObject)
+        return MoleculeContainer.nameForReuse(with: model, delegateObject)
     }
     
     public override class func requiredModules(with model: MoleculeModelProtocol, _ delegateObject: MVMCoreUIDelegateObject?, error: AutoreleasingUnsafeMutablePointer<MVMCoreErrorObject?>?) -> [String]? {

MVMCoreUI/Atomic/Molecules/Items/StackItemModel.swift

@@ -36,4 +36,12 @@
     required public init(from decoder: Decoder) throws {
         fatalError("init(from:) has not been implemented")
     }
+    
+    public override func isEqual(to model: any ModelComparisonProtocol) -> Bool {
+        guard let model = model as? Self else { return false }
+        return backgroundColor == model.backgroundColor
+        && spacing == model.spacing
+        && percent == model.percent
+        && gone == model.gone
+    }
 }

MVMCoreUI/Atomic/Molecules/Items/TabsListItemModel.swift

@@ -20,20 +20,21 @@ public class TabsListItemModel: ListItemModel, ParentMoleculeModelProtocol {
     private var addedMolecules: [ListItemModelProtocol & MoleculeModelProtocol]?
 
     public var children: [MoleculeModelProtocol] {
-        return molecules.flatMap { $0 }
+        return [tabs] + molecules.flatMap { $0 }
     }
     
-    public func replaceChildMolecule(with replacementMolecule: MoleculeModelProtocol) throws -> Bool {
+    public func replaceChildMolecule(with replacementMolecule: MoleculeModelProtocol) throws -> MoleculeModelProtocol? {
-        guard let replacementMolecule = replacementMolecule as? ListItemModelProtocol & MoleculeModelProtocol else { return false }
+        guard let replacementMolecule = replacementMolecule as? ListItemModelProtocol & MoleculeModelProtocol else { return nil }
         for (tabIndex, _) in molecules.enumerated() {
             for (elementIndex, _) in molecules[tabIndex].enumerated() {
                 if molecules[tabIndex][elementIndex].id == replacementMolecule.id {
+                    let replacedMolecule = molecules[tabIndex][elementIndex]
                     molecules[tabIndex][elementIndex] = replacementMolecule
-                    return true
+                    return replacedMolecule
                 }
             }
         }
-        return false
+        return nil
     }
     
     //--------------------------------------------------
@@ -90,6 +91,11 @@ public class TabsListItemModel: ListItemModel, ParentMoleculeModelProtocol {
         try container.encode(tabs, forKey: .tabs)
         try container.encodeModels2D(molecules, forKey: .molecules)
     }
+    
+    public override func isEqual(to model: any ModelComparisonProtocol) -> Bool {
+        guard super.isEqual(to: model), let model = model as? Self else { return false }
+        return molecules.count == model.molecules.count
+    }
 }
 
 extension TabsListItemModel: PageBehaviorProtocolRequirer {

MVMCoreUI/Atomic/Molecules/LeftRightViews/CornerLabelsModel.swift

@@ -23,12 +23,16 @@ public class CornerLabelsModel: ParentMoleculeModelProtocol {
         [molecule, topLeftLabel, topRightLabel, bottomLeftLabel, bottomRightLabel].compactMap { $0 }
     }
     
-    public func replaceChildMolecule(with molecule: MoleculeModelProtocol) throws -> Bool  {
+    public func replaceChildMolecule(with molecule: MoleculeModelProtocol) throws -> MoleculeModelProtocol? {
-        return try replaceChildMolecule(at: &self.molecule, with: molecule)
+        var replacedMolecule: MoleculeModelProtocol?
-        || replaceChildMolecule(at: &topLeftLabel, with: molecule)
+        if try replaceChildMolecule(at: &self.molecule, with: molecule, replaced: &replacedMolecule)
-        || replaceChildMolecule(at: &topRightLabel, with: molecule)
+            || replaceChildMolecule(at: &topLeftLabel, with: molecule, replaced: &replacedMolecule)
-        || replaceChildMolecule(at: &bottomLeftLabel, with: molecule)
+            || replaceChildMolecule(at: &topRightLabel, with: molecule, replaced: &replacedMolecule)
-        || replaceChildMolecule(at: &bottomRightLabel, with: molecule)
+            || replaceChildMolecule(at: &bottomLeftLabel, with: molecule, replaced: &replacedMolecule)
+            || replaceChildMolecule(at: &bottomRightLabel, with: molecule, replaced: &replacedMolecule) {
+            return replacedMolecule
+        }
+        return nil
     }
     
     public init(with molecule: MoleculeModelProtocol?) {

MVMCoreUI/Atomic/Molecules/NavigationBar/Buttons/NavigationImageButtonModel.swift

@@ -73,6 +73,25 @@ public class NavigationImageButtonModel: NavigationButtonModelProtocol, Molecule
         try container.encodeIfPresent(imageRenderingMode, forKey: .imageRenderingMode)
     }
     
+    public func isEqual(to model: any ModelComparisonProtocol) -> Bool {
+        guard let model = model as? Self else { return true }
+        return backgroundColor == model.backgroundColor
+        && accessibilityIdentifier == model.accessibilityIdentifier
+        && image == model.image
+        && accessibilityText == model.accessibilityText
+        && imageRenderingMode == model.imageRenderingMode
+        && action.isEqual(to: action)
+    }
+    
+    public func isVisuallyEquivalent(to model: any MoleculeModelComparisonProtocol) -> Bool {
+        guard let model = model as? Self else { return true }
+        return backgroundColor == model.backgroundColor
+        && accessibilityIdentifier == model.accessibilityIdentifier
+        && image == model.image
+        && accessibilityText == model.accessibilityText
+        && imageRenderingMode == model.imageRenderingMode
+    }
+    
     //--------------------------------------------------
     // MARK: - Method
     //--------------------------------------------------

MVMCoreUI/Atomic/Molecules/NavigationBar/NavigationItemModel.swift

@@ -129,6 +129,24 @@ open class NavigationItemModel: NavigationItemModelProtocol, MoleculeModelProtoc
         try container.encodeIfPresent(style, forKey: .style)
         try container.encodeIfPresent(titleOffset, forKey: .titleOffset)
     }
+    
+    open func isEqual(to model: any ModelComparisonProtocol) -> Bool {
+        guard let model = model as? Self else { return false }
+        return backgroundColor == model.backgroundColor
+        && title == model.title
+        && hidden == model.hidden
+        && tintColor == model.tintColor
+        && line.isEqual(to: model.line)
+        && hidesSystemBackButton == model.hidesSystemBackButton
+        && style == model.style
+        && titleOffset == model.titleOffset
+        && titleView.isEqual(to: model.titleView)
+        && additionalLeftButtons.isEqual(to: model.additionalLeftButtons)
+        && additionalRightButtons.isEqual(to: model.additionalRightButtons)
+        && backButton.isEqual(to: model.backButton)
+        && alwaysShowBackButton == model.alwaysShowBackButton
+        && hidesSystemBackButton == model.hidesSystemBackButton
+    }
 }
 
 extension NavigationItemModel: ParentMoleculeModelProtocol {

MVMCoreUI/Atomic/Molecules/OtherContainers/MoleculeContainerModel.swift

@@ -20,7 +20,7 @@ open class MoleculeContainerModel: ContainerModel, MoleculeContainerModelProtoco
         return [molecule]
     }
     
-    public func replaceChildMolecule(with molecule: MoleculeModelProtocol) throws -> Bool  {
+    public func replaceChildMolecule(with molecule: MoleculeModelProtocol) throws -> MoleculeModelProtocol? {
         return try replaceChildMolecule(at: &self.molecule, with: molecule)
     }
     
@@ -61,4 +61,14 @@ open class MoleculeContainerModel: ContainerModel, MoleculeContainerModelProtoco
         try container.encodeModel(molecule, forKey: .molecule)
         try container.encodeIfPresent(backgroundColor, forKey: .backgroundColor)
     }
+    
+    public override func isEqual(to model: any ModelComparisonProtocol) -> Bool {
+        guard super.isEqual(to: model), let model = model as? Self else { return false }
+        return backgroundColor == model.backgroundColor
+    }
+    
+    // Declare for overrides.
+    public func isVisuallyEquivalent(to model: any MoleculeModelComparisonProtocol) -> Bool {
+        return isEqual(to: model)
+    }
 }

MVMCoreUI/Atomic/Molecules/OtherContainers/MoleculeContainerProtocol.swift

@@ -19,7 +19,7 @@ public extension MoleculeContainerModelProtocol {
 }
 
 public extension MoleculeContainerModelProtocol where Self: AnyObject {
-    mutating func replaceChildMolecule(with replacementMolecule: MoleculeModelProtocol) throws -> Bool {
+    mutating func replaceChildMolecule(with replacementMolecule: MoleculeModelProtocol) throws -> MoleculeModelProtocol? {
         return try replaceChildMolecule(at: &molecule, with: replacementMolecule)
     }
 }

MVMCoreUI/Atomic/Molecules/VerticalCombinationViews/EyebrowHeadlineBodyLinkModel.swift

@@ -7,7 +7,7 @@
 //
 
 
-public class EyebrowHeadlineBodyLinkModel: MoleculeModelProtocol, ParentMoleculeModelProtocol {
+public class EyebrowHeadlineBodyLinkModel: ParentMoleculeModelProtocol {
     //--------------------------------------------------
     // MARK: - Properties
     //--------------------------------------------------
@@ -25,11 +25,15 @@ public class EyebrowHeadlineBodyLinkModel: MoleculeModelProtocol, ParentMolecule
         [eyebrow, headline, body, link].compactMap { (molecule: MoleculeModelProtocol?) in molecule }
     }
     
-    public func replaceChildMolecule(with molecule: MoleculeModelProtocol) throws -> Bool  {
+    public func replaceChildMolecule(with molecule: MoleculeModelProtocol) throws -> MoleculeModelProtocol? {
-        return try replaceChildMolecule(at: &eyebrow, with: molecule)
+        var replacedMolecule: MoleculeModelProtocol?
-        || replaceChildMolecule(at: &headline, with: molecule)
+        if try replaceChildMolecule(at: &eyebrow, with: molecule, replaced: &replacedMolecule)
-        || replaceChildMolecule(at: &body, with: molecule)
+            || replaceChildMolecule(at: &headline, with: molecule, replaced: &replacedMolecule)
-        || replaceChildMolecule(at: &link, with: molecule)
+            || replaceChildMolecule(at: &body, with: molecule, replaced: &replacedMolecule)
+            || replaceChildMolecule(at: &link, with: molecule, replaced: &replacedMolecule) {
+            return replacedMolecule
+        }
+        return nil
     }
     
     //--------------------------------------------------
@@ -102,4 +106,13 @@ public class EyebrowHeadlineBodyLinkModel: MoleculeModelProtocol, ParentMolecule
         try container.encodeIfPresent(body, forKey: .body)
         try container.encodeIfPresent(link, forKey: .link)
     }
+    
+    public func isEqual(to model: any ModelComparisonProtocol) -> Bool {
+        guard let model = model as? Self else { return false }
+        return backgroundColor == model.backgroundColor
+        && eyebrow.matchExistence(with: model.eyebrow)
+        && headline.matchExistence(with: model.headline)
+        && body.matchExistence(with: model.body)
+        && link.matchExistence(with: model.link)
+    }
 }

MVMCoreUI/Atomic/Molecules/VerticalCombinationViews/HeadlineBodyModel.swift

@@ -24,9 +24,13 @@ open class HeadlineBodyModel: ParentMoleculeModelProtocol {
         [headline, body].compactMap { $0 }
     }
     
-    public func replaceChildMolecule(with replacementMolecule: MoleculeModelProtocol) throws -> Bool {
+    public func replaceChildMolecule(with replacementMolecule: MoleculeModelProtocol) throws -> MoleculeModelProtocol? {
-        return try replaceChildMolecule(at:&headline, with: replacementMolecule)
+        var replacedMolecule: MoleculeModelProtocol?
-        || replaceChildMolecule(at:&body, with: replacementMolecule)
+        if try replaceChildMolecule(at:&headline, with: replacementMolecule, replaced: &replacedMolecule)
+            || replaceChildMolecule(at:&body, with: replacementMolecule, replaced: &replacedMolecule) {
+            return replacedMolecule
+        }
+        return nil
     }
     
     //--------------------------------------------------
@@ -89,6 +93,12 @@ open class HeadlineBodyModel: ParentMoleculeModelProtocol {
         try container.encodeIfPresent(style, forKey: .style)
         try container.encodeIfPresent(backgroundColor, forKey: .backgroundColor)
     }
+    
+    public func isEqual(to model: any ModelComparisonProtocol) -> Bool {
+        guard let model = model as? Self else { return false }
+        return style == style
+        && backgroundColor == model.backgroundColor
+    }
 }
 
 public extension HeadlineBodyModel {

MVMCoreUI/Atomic/Organisms/Carousel/Carousel.swift

@@ -166,9 +166,26 @@ open class Carousel: View {
     
     public override func set(with model: MoleculeModelProtocol, _ delegateObject: MVMCoreUIDelegateObject?, _ additionalData: [AnyHashable: Any]?) {
         self.delegateObject = delegateObject
+        let originalModel = self.model as? CarouselModel
         super.set(with: model, delegateObject, additionalData)
         
         guard let carouselModel = model as? CarouselModel else { return }
+        
+        MVMCoreLoggingHandler.shared()?.handleDebugMessage("[\(Self.self)] [\(ObjectIdentifier(self).hashValue)]\noriginal model: \(originalModel?.debugDescription ?? "none")\nnew model: \(model)")
+        
+        if #available(iOS 15.0, *) {
+            if let originalModel, carouselModel.isDeeplyVisuallyEquivalent(to: originalModel) {
+                // Prevents a carousel reset while still updating the cell backing data through reconfigureItems.
+                MVMCoreLoggingHandler.shared()?.handleDebugMessage("[\(Self.self)] Model is visually equivalent. Skipping rebuild...")
+                FormValidator.setupValidation(for: carouselModel, delegate: delegateObject?.formHolderDelegate)
+                updateModelIndex() // Ensure the new model indexing matches the old.
+                pagingView?.currentIndex = pageIndex // Trigger a paging view render.
+                collectionView.reconfigureItems(at: collectionView.indexPathsForVisibleItems)
+                return
+            }
+        }
+        
+        MVMCoreLoggingHandler.shared()?.handleDebugMessage("[\(Self.self)] Model is new. Rebuilding carousel.")
         accessibilityLabel = carouselModel.accessibilityText
         collectionView.layer.borderColor = UIColor.mvmCoolGray3.cgColor
         collectionView.layer.borderWidth = (carouselModel.border ?? false) ? 1 : 0

MVMCoreUI/Atomic/Organisms/Carousel/CarouselModel.swift

@@ -171,6 +171,48 @@ import UIKit
         try container.encode(enabled, forKey: .enabled)
         try container.encode(readOnly, forKey: .readOnly)
     }
+    
+    public func isEqual(to model: any ModelComparisonProtocol) -> Bool {
+        guard let model = model as? Self else { return false }
+        return backgroundColor == backgroundColor
+        && spacing == model.spacing
+        && border == model.border
+        && loop == model.loop
+        && height == model.height
+        && itemWidthPercent == model.itemWidthPercent
+        && itemAlignment == model.itemAlignment
+        && paging == model.paging
+        && useHorizontalMargins == model.useHorizontalMargins
+        && leftPadding == model.leftPadding
+        && rightPadding == model.rightPadding
+        && accessibilityText == model.accessibilityText
+        && baseValue == model.baseValue
+        && fieldKey == model.fieldKey
+        && groupName == model.groupName
+        && enabled == model.enabled
+        && readOnly == model.readOnly
+        && molecules.count == model.molecules.count
+        && pagingMolecule.matchExistence(with: model.pagingMolecule)
+    }
+    
+    public func isVisuallyEquivalent(to model: any MoleculeModelComparisonProtocol) -> Bool {
+        guard let model = model as? Self else  { return false }
+        return backgroundColor == backgroundColor
+        && spacing == model.spacing
+        && border == model.border
+        && loop == model.loop
+        && height == model.height
+        && itemWidthPercent == model.itemWidthPercent
+        && itemAlignment == model.itemAlignment
+        && paging == model.paging
+        && useHorizontalMargins == model.useHorizontalMargins
+        && leftPadding == model.leftPadding
+        && rightPadding == model.rightPadding
+        && accessibilityText == model.accessibilityText
+        && baseValue == model.baseValue
+        && enabled == model.enabled
+        && readOnly == model.readOnly
+    }
 }
 
 extension CarouselModel {
@@ -179,8 +221,16 @@ extension CarouselModel {
         return molecules
     }
     
-    public func replaceChildMolecule(with molecule: MoleculeModelProtocol) throws -> Bool  {
+    public func replaceChildMolecule(with molecule: MoleculeModelProtocol) throws -> MoleculeModelProtocol? {
         return try replaceChildMolecule(in: &molecules, with: molecule)
     }
     
 }
+
+extension CarouselModel: CustomDebugStringConvertible {
+    
+    public var debugDescription: String {
+        return "\(molecules.count) \(molecules.map { ($0 as? CarouselItemModel)?.molecule.moleculeName ?? "unknown" } )"
+    }
+    
+}

MVMCoreUI/Atomic/Organisms/StackModel.swift

@@ -79,4 +79,11 @@
         try container.encodeIfPresent(backgroundColor, forKey: .backgroundColor)
     }
     
+    public override func isEqual(to model: any ModelComparisonProtocol) -> Bool {
+        guard let model = model as? Self else { return false }
+        return backgroundColor == model.backgroundColor
+        && axis == model.axis
+        && spacing == model.spacing
+        && molecules.count == model.molecules.count
+    }
 }

MVMCoreUI/Atomic/Organisms/StackModelProtocol.swift

@@ -21,7 +21,7 @@ extension StackModelProtocol {
 
 extension StackModelProtocol where Self: AnyObject {
     
-    public mutating func replaceChildMolecule(with molecule: MoleculeModelProtocol) throws -> Bool  {
+    public mutating func replaceChildMolecule(with molecule: MoleculeModelProtocol) throws -> MoleculeModelProtocol?  {
         return try replaceChildMolecule(in: &molecules, with: molecule)
     }
 }

MVMCoreUI/Atomic/Protocols/ModelProtocols/MoleculeComparisonProtocol.swift

@@ -0,0 +1,72 @@
+//
+//  MoleculeComparisonProtocol.swift
+//  MVMCoreUI
+//
+//  Created by Kyle Hedden on 4/29/24.
+//  Copyright © 2024 Verizon Wireless. All rights reserved.
+//
+
+import Foundation
+
+public protocol MoleculeModelComparisonProtocol: ModelComparisonProtocol {
+    
+    /**  
+     Shallow check if there are no visual differences between models.
+        
+     By default if the models are equal then they are visually equivalent. However, if there are parts of models that can be updated without a UI update, this could be subset of properties.
+     **/
+    func isVisuallyEquivalent(to model: MoleculeModelComparisonProtocol) -> Bool
+}
+
+extension MoleculeModelComparisonProtocol {
+    
+    public func isVisuallyEquivalent(to model: MoleculeModelComparisonProtocol) -> Bool {
+        return isEqual(to: model)
+    }
+}
+
+public extension MoleculeModelComparisonProtocol where Self: ParentModelProtocol {
+    func isDeeplyVisuallyEquivalent(to model: any MoleculeModelComparisonProtocol) -> Bool {
+        guard let model = model as? Self else { return false }
+        return !findFirst(in: model, failing: { mine, theirs in
+            guard let mine = mine as? MoleculeModelComparisonProtocol, let theirs = theirs as? MoleculeModelComparisonProtocol else { return false }
+            return mine.isVisuallyEquivalent(to: theirs)
+        }).matched
+    }
+}
+
+public extension Optional {
+    
+    /// Checks if the current model is equal to another model.
+    func isVisuallyEquivalent(to model: MoleculeModelComparisonProtocol?) -> Bool {
+        guard let self = self as? MoleculeModelComparisonProtocol else {
+            return model == nil
+        }
+        guard let model = model else {
+            return false
+        }
+        return self.isVisuallyEquivalent(to: model)
+    }
+}
+
+public extension Collection {
+    /// Checks if all the models in the given collection match another given collection.
+    func isVisuallyEquivalent(to models: [MoleculeModelComparisonProtocol]) -> Bool {
+        guard count == models.count, let self = self as? [MoleculeModelComparisonProtocol] else { return false }
+        return models.indices.allSatisfy { index in
+            self[index].isVisuallyEquivalent(to: models[index])
+        }
+    }
+}
+
+public extension Optional where Wrapped: Collection {
+    func isVisuallyEquivalent(to models: [MoleculeModelComparisonProtocol]?) -> Bool {
+        guard let self = self as? [MoleculeModelComparisonProtocol] else {
+            return models == nil
+        }
+        guard let models = models else {
+            return false
+        }
+        return self.isVisuallyEquivalent(to: models)
+    }
+}

MVMCoreUI/Atomic/Protocols/ModelProtocols/MoleculeModelProtocol.swift

@@ -5,7 +5,7 @@ public enum MolecularError: Swift.Error {
     case countImbalance(String)
 }
 
-public protocol MoleculeModelProtocol: ModelProtocol, AccessibilityModelProtocol, MoleculeTreeTraversalProtocol, MoleculeMaskingProtocol {
+public protocol MoleculeModelProtocol: ModelProtocol, AccessibilityModelProtocol, MoleculeTreeTraversalProtocol, MoleculeMaskingProtocol, MoleculeModelComparisonProtocol, CustomDebugStringConvertible {
     var moleculeName: String { get }
     var backgroundColor: Color? { get set }
     var id: String { get }
@@ -18,6 +18,16 @@ public extension MoleculeModelProtocol {
     static var categoryName: String { "\(MoleculeModelProtocol.self)" }
     
     static var categoryCodingKey: String { "moleculeName" }
+    
+    func isEqual(to model: ModelComparisonProtocol) -> Bool {
+        guard let model = model as? Self else { return false }
+        return moleculeName == model.moleculeName
+        && backgroundColor == model.backgroundColor
+    }
+    
+    var debugDescription: String {
+        return "\(moleculeName): \(id)"
+    }
 }
 
 // Helpers made due to swift not able to reconcile which category.

MVMCoreUI/Atomic/Protocols/ModelProtocols/ParentMoleculeModelProtocol.swift

@@ -8,48 +8,61 @@
 
 import Foundation
 
-public protocol ParentModelProtocol: MoleculeTreeTraversalProtocol {
+public protocol ParentModelProtocol: ModelProtocol, MoleculeTreeTraversalProtocol {
     
     /// Returns the direct children of this component. (Does not recurse.)
     var children: [MoleculeModelProtocol] { get }
     
     /// Method for replacing surface level children. (Does not recurse.)
-    mutating func replaceChildMolecule(with molecule: MoleculeModelProtocol) throws -> Bool
+    mutating func replaceChildMolecule(with molecule: MoleculeModelProtocol) throws -> MoleculeModelProtocol?
 }
 
 public extension ParentModelProtocol where Self: AnyObject {
         
     /// Top level test to replace child molecules. Each parent molecule should attempt to replace.
-    func replaceChildMolecule(with molecule: MoleculeModelProtocol) throws -> Bool { return false }
+    func replaceChildMolecule(with molecule: MoleculeModelProtocol) throws -> MoleculeModelProtocol? { return nil }
+    
+    func replaceChildMolecule<T>(at childMolecule: inout T, with replacementMolecule: MoleculeModelProtocol) throws -> MoleculeModelProtocol? {
+        var replacedMolecule: MoleculeModelProtocol?
+        return try replaceChildMolecule(at: &childMolecule, with: replacementMolecule, replaced: &replacedMolecule) ? replacedMolecule : nil
+    }
     
     /// Helper function for replacing a single molecules with type and optionality checks.
-    func replaceChildMolecule<T>(at childMolecule: inout T, with replacementMolecule: MoleculeModelProtocol) throws -> Bool {
+    func replaceChildMolecule<T>(at childMolecule: inout T, with replacementMolecule: MoleculeModelProtocol, replaced: inout MoleculeModelProtocol?) throws -> Bool {
         guard let childIdMolecule = childMolecule as? MoleculeModelProtocol else { return false }
         if childIdMolecule.id == replacementMolecule.id {
-            guard let replacementMolecule = replacementMolecule as? T else {
+            guard let typedReplacementMolecule = replacementMolecule as? T else {
                 throw MolecularError.error("Molecular replacement '\(replacementMolecule.id)' does not type match \(type(of: T.self)) of \(type(of: self))")
             }
-            childMolecule = replacementMolecule
+            replaced = childIdMolecule
+            childMolecule = typedReplacementMolecule
             return true
         }
         return false
     }
     
+    func replaceChildMolecule<T>(in molecules: inout [T], with replacementMolecule: MoleculeModelProtocol) throws -> MoleculeModelProtocol? {
+        var replacedMolecule: MoleculeModelProtocol?
+        return try replaceChildMolecule(at: &molecules, with: replacementMolecule, replaced: &replacedMolecule) ? replacedMolecule : nil
+    }
+    
     /// Helper for replacing a molecule in place within an array. Note the "in".
-    func replaceChildMolecule<T>(in molecules: inout [T], with replacementMolecule: MoleculeModelProtocol) throws -> Bool {
+    func replaceChildMolecule<T>(in molecules: inout [T], with replacementMolecule: MoleculeModelProtocol, replaced: inout MoleculeModelProtocol?) throws -> Bool {
-        guard let moleculeIdModels = molecules as? [MoleculeModelProtocol], let matchingIndex = moleculeIdModels.firstIndex(where: {
+        guard let moleculeIdModels = molecules as? [MoleculeModelProtocol],
-            $0.id == replacementMolecule.id
+              let matchingIndex = moleculeIdModels.firstIndex(where: {
-        }) else { return false }
+                  $0.id == replacementMolecule.id
-        guard let replacementMolecule = replacementMolecule as? T else {
+              }) 
+        else { return false }
+        guard let typedReplacementMolecule = replacementMolecule as? T else {
             throw MolecularError.error("Molecular replacement '\(replacementMolecule.id)' does not type match \(type(of: T.self)) of \(type(of: self))")
         }
-        molecules[matchingIndex] = replacementMolecule
+        replaced = molecules[matchingIndex] as? MoleculeModelProtocol
+        molecules[matchingIndex] = typedReplacementMolecule
         return true
     }
 }
 
 public protocol ParentMoleculeModelProtocol: ParentModelProtocol, MoleculeModelProtocol {
-    
 }
 
 public extension ParentMoleculeModelProtocol {
@@ -64,7 +77,7 @@ public extension ParentMoleculeModelProtocol {
                 // Safety net to make sure the ParentMoleculeModelProtocol's method extension is called over the base MoleculeModelProtocol.
                 return additionalParent.reduceDepthFirstTraverse(options: options, depth: depth + 1, initialResult: result, nextPartialResult: nextPartialResult)
             }
-            return molecule.reduceDepthFirstTraverse(options: options, depth: depth + 1, initialResult: result, nextPartialResult: nextPartialResult)
+            return nextPartialResult(result, molecule, depth + 1)
         }
         if (options == .childFirst) {
             result = nextPartialResult(result, self, depth)
@@ -88,7 +101,7 @@ public extension ParentMoleculeModelProtocol {
                 // Safety net to make sure the ParentMoleculeModelProtocol's method extension is called over the base MoleculeModelProtocol.
                 additionalParent.depthFirstTraverse(options: options, depth: depth + 1, onVisit: stopIntercept)
             } else {
-                child.depthFirstTraverse(options: options, depth: depth + 1, onVisit: stopIntercept)
+                onVisit(depth, child, &shouldStop)
             }
             guard !shouldStop else { return }
         }
@@ -98,3 +111,83 @@ public extension ParentMoleculeModelProtocol {
         // if options == .leafOnly don't call on self.
     }
 }
+
+public extension ParentModelProtocol {
+    
+    typealias DeepCompareResult = (matched: Bool, mine: ModelProtocol?, theirs: ModelProtocol?)
+    
+    typealias ModelPair = (mine: ModelProtocol, theirs: ModelProtocol)
+    
+    func deepEquals(to model: any ModelProtocol) -> Bool {
+        guard let model = model as? ParentModelProtocol else { return false }
+        return !findFirst(in: model, failing: { $0.isEqual(to: $1) }).matched
+    }
+    
+    func findFirst(in anotherParent: ParentModelProtocol, failing test: (ModelProtocol, ModelProtocol)->Bool, options: TreeTraversalOptions = .childFirst) -> DeepCompareResult {
+        
+        guard options != .parentFirst, test(self, anotherParent) else { return (true, mine: self, theirs: anotherParent)}
+        
+        let myChildren = children
+        let theirChildren = anotherParent.children
+        guard myChildren.count == theirChildren.count else { return (true, mine: self, theirs: anotherParent) }
+        for index in myChildren.indices {
+            if let myChild = myChildren[index] as? ParentModelProtocol {
+                if let theirChild = theirChildren[index] as? ParentModelProtocol {
+                    let result = myChild.findFirst(in: theirChild, failing: test)
+                    guard !result.0 else { return result }
+                } else {
+                    return (true, mine: myChild, theirs: theirChildren[index])
+                }
+            } else if !test(myChildren[index], theirChildren[index]) {
+                return (true, mine: myChildren[index], theirs: theirChildren[index])
+            }
+        }
+        
+        guard options == .childFirst, test(self, anotherParent) else { return (true, mine: self, theirs: anotherParent)}
+        
+        return (false, nil, nil)
+    }
+    
+    func findAllTheirsNotEqual<T>(against anotherParent: ParentModelProtocol) -> [T] {
+        return deepCompare(against: anotherParent) { $0.isEqual(to: $1) }.compactMap { $0.theirs as? T }
+    }
+    
+    func findAllNotEqual(against anotherParent: ParentModelProtocol) -> [ModelPair] {
+        return deepCompare(against: anotherParent) { $0.isEqual(to: $1) }
+    }
+    
+    func deepCompare(against anotherParent: ParentModelProtocol, where test: (ModelProtocol, ModelProtocol)->Bool) -> [ModelPair] {
+        
+        var allDiffs = [ModelPair]()
+        
+        let myChildren = children
+        let theirChildren = anotherParent.children
+        guard myChildren.count == theirChildren.count else { return [(self, anotherParent)] }
+        
+        if !test(self, anotherParent) {
+            allDiffs.append((self, anotherParent))
+        }
+
+        for index in myChildren.indices {
+            if let myChild = myChildren[index] as? ParentModelProtocol, 
+                let theirChild = theirChildren[index] as? ParentModelProtocol {
+                    let childDiffs = myChild.deepCompare(against: theirChild, where: test)
+                    allDiffs.append(contentsOf: childDiffs)
+            } else if !test(myChildren[index], theirChildren[index]) {
+                allDiffs.append((myChildren[index], theirChildren[index]))
+            }
+        }
+        
+        return allDiffs
+    }
+}
+
+public extension ModelComparisonProtocol where Self: MoleculeModelProtocol {
+    
+    func deepEquals(to model: ModelProtocol) -> Bool {
+        if let self = self as? ParentModelProtocol {
+            return self.deepEquals(to: model)
+        }
+        return isEqual(to: model)
+    }
+}

MVMCoreUI/Atomic/Protocols/ModelProtocols/TemplateModelProtocol.swift

@@ -7,9 +7,11 @@
 //
 
 
-public protocol TemplateModelProtocol: PageModelProtocol, ModelProtocol, MoleculeTreeTraversalProtocol, ParentModelProtocol {
+public protocol TemplateModelProtocol: PageModelProtocol, ModelProtocol, MoleculeTreeTraversalProtocol, ParentModelProtocol, MoleculeModelComparisonProtocol {
     var template: String { get }
     var rootMolecules: [MoleculeModelProtocol] { get }
+    /// Page rendering ID. Unique betwen JSON parses.
+    var id: String { get }
 }
 
 public extension TemplateModelProtocol {
@@ -42,27 +44,27 @@ public extension TemplateModelProtocol {
 extension TemplateModelProtocol {
     
     /// Recursively finds and replaces the first child matching the replacement molecule id property.
-    mutating func replaceMolecule(with replacementMolecule: MoleculeModelProtocol) throws -> Bool {
+    mutating func replaceMolecule(with replacementMolecule: MoleculeModelProtocol) throws -> MoleculeModelProtocol? {
         // Attempt root level replacement on the template model first.
-        if try replaceChildMolecule(with: replacementMolecule) {
+        if let replacedMolecule = try replaceChildMolecule(with: replacementMolecule) {
-            return true
+            return replacedMolecule
         }
         
-        var didReplaceMolecule = false
+        var replacedMolecule: MoleculeModelProtocol?
         var possibleError: Error?
         // Dive into each root thereafter.
         depthFirstTraverse(options: .parentFirst, depth: 0) { depth, molecule, stop in
             guard var parentMolecule = molecule as? ParentMoleculeModelProtocol else { return }
             do {
-                didReplaceMolecule =  try parentMolecule.replaceChildMolecule(with: replacementMolecule)
+                replacedMolecule = try parentMolecule.replaceChildMolecule(with: replacementMolecule)
             } catch {
                 possibleError = error
             }
-            stop = didReplaceMolecule || possibleError != nil
+            stop = replacedMolecule != nil || possibleError != nil
         }
         if let error = possibleError {
             throw error
         }
-        return didReplaceMolecule
+        return replacedMolecule
     }
 }

MVMCoreUI/Atomic/Protocols/MoleculeDelegateProtocol.swift

@@ -21,9 +21,6 @@ public protocol MoleculeDelegateProtocol: AnyObject {
     
     /// Notifies the delegate that the molecule layout update. Should be called when the layout may change due to an async method. Mainly used for list or collections.
     func moleculeLayoutUpdated(_ molecule: MoleculeViewProtocol) //optional
-    
-    /// Attempts to replace the molecules provided. Returns the ones that replaced successfully.
-    func replaceMoleculeData(_ moleculeModels: [MoleculeModelProtocol], completionHandler: (([MoleculeModelProtocol])->Void)?)
 }
 
 extension MoleculeDelegateProtocol {

MVMCoreUI/Atomic/Protocols/MoleculeTreeTraversalProtocol.swift

@@ -38,7 +38,7 @@ public extension MoleculeTreeTraversalProtocol {
     
     func printMolecules(options: TreeTraversalOptions = .parentFirst) {
         depthFirstTraverse(options: options, depth: 1) { depth, molecule, stop in
-            print("\(String(repeating: ">>", count: depth)) \"\(molecule.moleculeName)\" [\(molecule): \(molecule.id)]")
+            print("\(String(repeating: ">>", count: depth)) \"\(molecule.moleculeName)\" [\(molecule)]")
         }
     }
     

MVMCoreUI/Atomic/Protocols/TemplateProtocol.swift

@@ -35,19 +35,26 @@ public extension TemplateProtocol {
 
 public extension TemplateProtocol where Self: PageBehaviorHandlerProtocol, Self: MVMCoreViewControllerProtocol {
     
+    func parseTemplate(loadObject: MVMCoreLoadObject) throws -> TemplateModelProtocol {
+        guard let pageJSON = loadObject.pageJSON else {
+            throw MVMCoreError.error(code: ErrorCode.parsingJSON.rawValue, messageToDisplay: "", messageToLog: "Load object is missing its page JSON!")
+        }
+        return try parseTemplate(pageJSON: pageJSON)
+    }
+    
     /// Helper function to do common parsing logic.
-    func parseTemplate(json: [AnyHashable: Any]?) throws {
+    func parseTemplate(pageJSON: [AnyHashable: Any]) throws -> TemplateModelProtocol {
-        guard let pageJSON = json else { return }
         let delegateObject = delegateObject?() as? MVMCoreUIDelegateObject
         let data = try JSONSerialization.data(withJSONObject: pageJSON)
         let decoder = JSONDecoder.create(with: delegateObject)
-        templateModel = try decodeTemplate(using: decoder, from: data)
+        let templateModel = try decodeTemplate(using: decoder, from: data)
         
-        // Add additional required behaviors if applicable.
+        // Add additional required behavior models to the template if applicable.
-        guard var pageBehaviorsModel = templateModel as? TemplateModelProtocol & PageBehaviorContainerModelProtocol else  { return }
+        guard var templateBehaviorsModel = templateModel as? TemplateModelProtocol & PageBehaviorContainerModelProtocol else {
+            return templateModel
+        }
+        templateBehaviorsModel.traverseAndAddRequiredBehaviors()
         
-        pageBehaviorsModel.traverseAndAddRequiredBehaviors()
+        return templateModel
-        var behaviorHandler = self
-        behaviorHandler.applyBehaviors(pageBehaviorModel: pageBehaviorsModel, delegateObject: delegateObject)
     }
 }

MVMCoreUI/Atomic/Templates/BaseTemplateModel.swift

@@ -10,11 +10,14 @@ import Foundation
 
 
 @objcMembers open class BaseTemplateModel: MVMControllerModelProtocol, TabPageModelProtocol {
+    
     //--------------------------------------------------
     // MARK: - Properties
     //--------------------------------------------------
     open class var identifier: String { "" }
     
+    public var id: String = UUID().uuidString
+    
     public var pageType: String
     public var template: String {
         // Although this is done in the extension, it is needed for the encoding.
@@ -35,8 +38,12 @@ import Foundation
     public var hideLeftPanel: Bool?
     public var hideRightPanel: Bool?
     
-    public func replaceChildMolecule(with molecule: MoleculeModelProtocol) throws -> Bool {
+    public func replaceChildMolecule(with molecule: MoleculeModelProtocol) throws -> MoleculeModelProtocol? {
-        return try replaceChildMolecule(at: &navigationBar, with: molecule)
+        var replacedMolecule: MoleculeModelProtocol?
+        if try replaceChildMolecule(at: &navigationBar, with: molecule, replaced: &replacedMolecule) {
+            return replacedMolecule
+        }
+        return nil
     }
     
     //--------------------------------------------------
@@ -114,4 +121,18 @@ import Foundation
         try container.encodeIfPresent(tabBarIndex, forKey: .tabBarIndex)
         try container.encode(shouldMaskScreenWhileRecording, forKey: .shouldMaskScreenWhileRecording)
     }
+    
+    public func isEqual(to model: any ModelComparisonProtocol) -> Bool {
+        guard let model = model as? Self else { return false }
+        return pageType == model.pageType
+        && backgroundColor == model.backgroundColor
+        && screenHeading == model.screenHeading
+        && formRules?.count ?? 0 == model.formRules?.count ?? 0
+        && navigationBar.matchExistence(with: model.navigationBar)
+        && tabBarHidden == model.tabBarHidden
+        && hideLeftPanel == model.hideLeftPanel
+        && hideRightPanel == model.hideRightPanel
+        && tabBarIndex == model.tabBarIndex
+        && shouldMaskScreenWhileRecording == model.shouldMaskScreenWhileRecording
+    }
 }

MVMCoreUI/Atomic/Templates/CollectionTemplate.swift

@@ -21,9 +21,8 @@
     //--------------------------------------------------
     // MARK: - Computed Properties
     //--------------------------------------------------
-    open override func parsePageJSON() throws {
+    open override func parsePageJSON(loadObject: MVMCoreLoadObject) throws -> PageModelProtocol {
-        try parseTemplate(json: loadObject?.pageJSON)
+        return try parseTemplate(loadObject: loadObject)
-        try super.parsePageJSON()
     }
     
     open override var loadObject: MVMCoreLoadObject? {
@@ -80,10 +79,10 @@
     }
     
     
-    open override func handleNewData() {
+    open override func handleNewData(_ pageModel: PageModelProtocol? = nil) {
         setup()
         registerCells()
-        super.handleNewData()
+        super.handleNewData(pageModel)
     }
     
     open override func updateUI(for molecules: [MoleculeModelProtocol]? = nil) {
@@ -134,7 +133,7 @@
         }
         update(cell: cell, size: view.frame.width)
         // Neded to fix an apple defect where the cell is not the correct size on certain devices for certain cells
-        cell.layoutIfNeeded()
+        cell.setNeedsLayout()
         return cell
     }
     

MVMCoreUI/Atomic/Templates/CollectionTemplateModel.swift

@@ -23,9 +23,14 @@
         return super.rootMolecules
     }
     
-    public override func replaceChildMolecule(with molecule: MoleculeModelProtocol) throws -> Bool {
+    public override func replaceChildMolecule(with molecule: MoleculeModelProtocol) throws -> MoleculeModelProtocol? {
-        return try super.replaceChildMolecule(with: molecule)
+        if let replacedMolecule = try super.replaceChildMolecule(with: molecule) {
-        || (molecules != nil && replaceChildMolecule(in: &(molecules!), with: molecule))
+            return replacedMolecule
+        }
+        if molecules != nil, let replacedMolecule = try replaceChildMolecule(in: &(molecules!), with: molecule) {
+            return replacedMolecule
+        }
+        return nil
     }
 
     //--------------------------------------------------

MVMCoreUI/Atomic/Templates/ListPageTemplateModel.swift

@@ -28,10 +28,16 @@
         return super.rootMolecules
     }
     
-    public override func replaceChildMolecule(with molecule: MoleculeModelProtocol) throws -> Bool {
+    public override func replaceChildMolecule(with molecule: MoleculeModelProtocol) throws -> MoleculeModelProtocol? {
-        return try super.replaceChildMolecule(with: molecule)
+        if let replacedMolecule = try super.replaceChildMolecule(with: molecule) {
-        || (molecules != nil && replaceChildMolecule(in: &(molecules!), with: molecule))
+            return replacedMolecule
-        || replaceChildMolecule(at: &line, with: molecule)
+        }
+        var replacedMolecule: MoleculeModelProtocol?
+        if try (molecules != nil && replaceChildMolecule(in: &(molecules!), with: molecule, replaced: &replacedMolecule))
+            || replaceChildMolecule(at: &line, with: molecule, replaced: &replacedMolecule) {
+            return replacedMolecule
+        }
+        return nil
     }
     
     /// This template requires content.
@@ -94,4 +100,14 @@
         try container.encodeIfPresent(footerlessSpacerColor, forKey: .footerlessSpacerColor)
         try container.encodeIfPresent(footerlessSpacerHeight, forKey: .footerlessSpacerHeight)
     }
+    
+    public override func isEqual(to model: any ModelComparisonProtocol) -> Bool {
+        guard super.isEqual(to: model), let model = model as? Self else { return false }
+        return line.matchExistence(with: model.line)
+        && scrollToRowIndex == model.scrollToRowIndex
+        && singleCellSelection == model.singleCellSelection
+        && footerlessSpacerColor == model.footerlessSpacerColor
+        && footerlessSpacerHeight == model.footerlessSpacerHeight
+        && molecules?.count ?? 0 == model.molecules?.count ?? 0
+    }
 }

MVMCoreUI/Atomic/Templates/ModalMoleculeListTemplate.swift

@@ -25,8 +25,8 @@ open class ModalMoleculeListTemplate: MoleculeListTemplate {
         try decoder.decode(ModalListPageTemplateModel.self, from: data)
     }
     
-    override open func handleNewData() {
+    override open func handleNewData(_ pageModel: PageModelProtocol? = nil) {
-        super.handleNewData()
+        super.handleNewData(pageModel)
         
         closeButton = MVMCoreUICommonViewsUtility.addCloseButton(to: view, action: { [weak self] _ in
             guard let self = self else { return }

MVMCoreUI/Atomic/Templates/ModalMoleculeStackTemplate.swift

@@ -23,8 +23,8 @@ open class ModalMoleculeStackTemplate: MoleculeStackTemplate {
     // MARK: - Lifecycle
     //--------------------------------------------------
     
-    override open func handleNewData() {
+    override open func handleNewData(_ pageModel: PageModelProtocol? = nil) {
-        super.handleNewData()
+        super.handleNewData(pageModel)
         _ = MVMCoreUICommonViewsUtility.addCloseButton(to: view, action: { [weak self] _ in
             guard let self = self else { return }
             let closeAction = (self.templateModel as? ModalStackPageTemplateModel)?.closeAction ??

MVMCoreUI/Atomic/Templates/MoleculeListTemplate.swift

@@ -46,9 +46,8 @@ open class MoleculeListTemplate: ThreeLayerTableViewController, TemplateProtocol
     // MARK: - Methods
     //--------------------------------------------------
     
-    open override func parsePageJSON() throws {
+    open override func parsePageJSON(loadObject: MVMCoreLoadObject) throws -> PageModelProtocol {
-        try parseTemplate(json: loadObject?.pageJSON)
+        return try parseTemplate(loadObject: loadObject)
-        try super.parsePageJSON()
     }
     
     // For subclassing the model.
@@ -86,23 +85,31 @@ open class MoleculeListTemplate: ThreeLayerTableViewController, TemplateProtocol
         return view
     }
     
-    open override func handleNewData() {
+    open override func handleNewData(_ pageModel: PageModelProtocol? = nil) {
-        setup()
+        super.handleNewData(pageModel)
-        registerWithTable()
+        
-        super.handleNewData() // Currently stuck as MoleculeListProtocol being called from AddRemoveMoleculesBehaviorModel.
+        if pageModel != nil {
+            setup()
+            registerWithTable()
+        }
     }
     
     open override func updateUI(for molecules: [MoleculeModelProtocol]? = nil) {
         topViewOutsideOfScrollArea = templateModel?.anchorHeader ?? false
         bottomViewOutsideOfScrollArea = templateModel?.anchorFooter ?? false
+        
         super.updateUI(for: molecules)
         
-        molecules?.forEach({ molecule in
+        guard let molecules else { return }
+        
+        // For updating individual specfied molecules. (Not a full table reload done in the base class.) These molecule types should remain the same type by replacement standards.
+        molecules.forEach({ molecule in
+            // Replace any top level cell data if required.
             if let index = moleculesInfo?.firstIndex(where: { $0.molecule.id == molecule.id }) {
                 moleculesInfo?[index].molecule = molecule
             }
-            newData(for: molecule)
         })
+        newData(for: molecules)
     }
     
     open override func viewDidAppear(_ animated: Bool) {
@@ -169,7 +176,7 @@ open class MoleculeListTemplate: ThreeLayerTableViewController, TemplateProtocol
         }
         (cell as? MVMCoreViewProtocol)?.updateView(tableView.bounds.width)
         // Neded to fix an apple defect where the cell is not the correct size on certain devices for certain cells
-        cell.layoutIfNeeded()
+        cell.setNeedsLayout()
         return cell
     }
     
@@ -233,18 +240,27 @@ open class MoleculeListTemplate: ThreeLayerTableViewController, TemplateProtocol
     }
     
     open func newData(for molecule: MoleculeModelProtocol) {
+        newData(for: [molecule])
+    }
+    
+    /// Refreshes all relevant cells for a given set of molecule models.
+    open func newData(for molecules: [MoleculeModelProtocol]) {
         
         //Check header and footer if replace happens then return.
-        if updateHeaderFooterView(topView, with: molecule) ||
+        molecules.forEach {
-            updateHeaderFooterView(bottomView, with: molecule, isHeader: false) {
+            if updateHeaderFooterView(topView, with: $0) ||
-            return
+                updateHeaderFooterView(bottomView, with: $0, isHeader: false) {
+                return
+            }
         }
         
         guard let moleculesInfo = moleculesInfo else { return }
         
         let indicies = moleculesInfo.indices.filter({ index -> Bool in
-            return moleculesInfo[index].molecule.findFirstMolecule(by: {
+            return moleculesInfo[index].molecule.findFirstMolecule(by: { existingMolecule in
-                $0.moleculeName == molecule.moleculeName && equal(moleculeA: molecule, moleculeB: $0)
+                molecules.contains { newMolecule in
+                    existingMolecule.moleculeName == newMolecule.moleculeName && equal(moleculeA: existingMolecule, moleculeB: newMolecule)
+                }
             }) != nil
         })
         
@@ -253,7 +269,16 @@ open class MoleculeListTemplate: ThreeLayerTableViewController, TemplateProtocol
         let indexPaths = indicies.map {
             return IndexPath(row: $0, section: 0)
         }
-        tableView.reloadRows(at: indexPaths, with: .automatic)
+        
+        debugLog("Refreshing rows \(indexPaths.map { $0.row })")
+        
+        if #available(iOS 15.0, *) {
+            // All rows should have been layed out already on the first newDataBuildScreen reload with the getMoleculeInfoList call. Therefore, we can be safe to assume the top level cell configuration will not be modified and only the child content will be updated allowing us to leverage this more efficient method.
+            tableView.reconfigureRows(at: indexPaths)
+        } else {
+            // A full reload can cause a flicker / animation. Better to avoid with above reconfigure method.
+            tableView.reloadRows(at: indexPaths, with: .automatic)
+        }
         if let selectedIndex = selectedIndex {
             tableView.selectRow(at: selectedIndex, animated: false, scrollPosition: .none)
         }
@@ -353,7 +378,7 @@ extension MoleculeListTemplate: MoleculeListProtocol {
               indexPaths.count > 0 else { return }
         tableView?.deleteRows(at: indexPaths, with: animation)
         updateViewConstraints()
-        view.layoutIfNeeded()
+        view.setNeedsLayout()
     }
     
     public func addMolecules(_ molecules: [ListItemModelProtocol & MoleculeModelProtocol], indexPath: IndexPath, animation: UITableView.RowAnimation?) {
@@ -372,7 +397,7 @@ extension MoleculeListTemplate: MoleculeListProtocol {
               indexPaths.count > 0 else { return }
         self.tableView?.insertRows(at: indexPaths, with: animation)
         self.updateViewConstraints()
-        self.view.layoutIfNeeded()
+        self.view.setNeedsLayout()
     }
     
     public func swapMolecules(_ molecules: [ListItemModelProtocol & MoleculeModelProtocol], with replacements: [ListItemModelProtocol & MoleculeModelProtocol], at indexPath: IndexPath, animation: UITableView.RowAnimation?) {
@@ -420,7 +445,7 @@ extension MoleculeListTemplate: MoleculeListProtocol {
         tableView.endUpdates()
         
         self.updateViewConstraints()
-        self.view.layoutIfNeeded()
+        self.view.setNeedsLayout()
     }
     
     public func getIndexPath(for molecule: ListItemModelProtocol & MoleculeModelProtocol) -> IndexPath? {

MVMCoreUI/Atomic/Templates/MoleculeStackTemplate.swift

@@ -20,10 +20,10 @@ open class MoleculeStackTemplate: ThreeLayerViewController, TemplateProtocol {
     // MARK: - Lifecycle
     //--------------------------------------------------
     
-    open override func handleNewData() {
+    open override func handleNewData(_ pageModel: PageModelProtocol? = nil) {
         topViewOutsideOfScroll = templateModel?.anchorHeader ?? false
         bottomViewOutsideOfScroll = templateModel?.anchorFooter ?? false
-        super.handleNewData()
+        super.handleNewData(pageModel)
     }
     
     // For subclassing the model.
@@ -31,9 +31,8 @@ open class MoleculeStackTemplate: ThreeLayerViewController, TemplateProtocol {
         return try decoder.decode(StackPageTemplateModel.self, from: data)
     }
     
-    open override func parsePageJSON() throws {
+    open override func parsePageJSON(loadObject: MVMCoreLoadObject) throws -> PageModelProtocol {
-        try parseTemplate(json: loadObject?.pageJSON)
+        return try parseTemplate(loadObject: loadObject)
-        try super.parsePageJSON()
     }
     
     open override var loadObject: MVMCoreLoadObject? {

MVMCoreUI/Atomic/Templates/SectionListTemplate.swift

@@ -112,7 +112,7 @@ open class SectionListTemplate: MoleculeListTemplate {
         (header as? MoleculeViewProtocol)?.set(with: headerInfo.molecule, delegateObjectIVar, nil)
         (header as? MVMCoreViewProtocol)?.updateView(tableView.bounds.width)
         // Neded to fix an apple defect where the cell is not the correct size on certain devices for certain cells
-        header?.layoutIfNeeded()
+        header?.setNeedsLayout()
         return header
     }
     
@@ -126,7 +126,7 @@ open class SectionListTemplate: MoleculeListTemplate {
         (footer as? MoleculeViewProtocol)?.set(with: footerInfo.molecule, delegateObjectIVar, nil)
         (footer as? MVMCoreViewProtocol)?.updateView(tableView.bounds.width)
         // Neded to fix an apple defect where the cell is not the correct size on certain devices for certain cells
-        footer?.layoutIfNeeded()
+        footer?.setNeedsLayout()
         return footer
     }
     

MVMCoreUI/Atomic/Templates/StackPageTemplateModel.swift

@@ -19,10 +19,14 @@
         super.rootMolecules + [moleculeStack]
     }
     
-    public override func replaceChildMolecule(with molecule: MoleculeModelProtocol) throws -> Bool {
+    public override func replaceChildMolecule(with molecule: MoleculeModelProtocol) throws -> MoleculeModelProtocol? {
+        var replacedMolecule: MoleculeModelProtocol?
         return try super.replaceChildMolecule(with: molecule)
-        || replaceChildMolecule(at: &navigationBar, with: molecule)
+        if try replaceChildMolecule(at: &navigationBar, with: molecule, replaced: &replacedMolecule)
-        || replaceChildMolecule(at: &moleculeStack, with: molecule)
+            || replaceChildMolecule(at: &moleculeStack, with: molecule, replaced: &replacedMolecule) {
+            return replacedMolecule
+        }
+        return nil
     }
     
     //--------------------------------------------------

MVMCoreUI/Atomic/Templates/ThreeLayerModelBase.swift

@@ -21,10 +21,16 @@
         [navigationBar, header, footer].compactMap { $0 }
     }
     
-    public override func replaceChildMolecule(with molecule: MoleculeModelProtocol) throws -> Bool {
+    public override func replaceChildMolecule(with molecule: MoleculeModelProtocol) throws -> MoleculeModelProtocol? {
-        return try super.replaceChildMolecule(with: molecule)
+        if let replacedMolecule = try super.replaceChildMolecule(with: molecule) {
-        || replaceChildMolecule(at: &header, with: molecule)
+            return replacedMolecule
-        || replaceChildMolecule(at: &footer, with: molecule)
+        }
+        var replacedMolecule: MoleculeModelProtocol?
+        if try replaceChildMolecule(at: &header, with: molecule, replaced: &replacedMolecule)
+            || replaceChildMolecule(at: &footer, with: molecule, replaced: &replacedMolecule) {
+            return replacedMolecule
+        }
+        return nil
     }
     
     //--------------------------------------------------
@@ -71,4 +77,12 @@
         try container.encodeIfPresent(anchorFooter, forKey: .anchorFooter)
         try container.encodeModelIfPresent(footer, forKey: .footer)
     }
+    
+    public override func isEqual(to model: any ModelComparisonProtocol) -> Bool {
+        guard super.isEqual(to: model), let model = model as? Self else { return false }
+        return anchorHeader == model.anchorHeader
+        && anchorFooter == model.anchorFooter
+        && header.matchExistence(with: model.header)
+        && footer.matchExistence(with: model.footer)
+    }
 }

MVMCoreUI/Atomic/Templates/ThreeLayerPageTemplateModel.swift

@@ -22,9 +22,15 @@
         return super.rootMolecules
     }
     
-    public override func replaceChildMolecule(with molecule: MoleculeModelProtocol) throws -> Bool {
+    public override func replaceChildMolecule(with molecule: MoleculeModelProtocol) throws -> MoleculeModelProtocol? {
-        return try super.replaceChildMolecule(with: molecule)
+        if let replacedMolecule = try super.replaceChildMolecule(with: molecule) {
-        || replaceChildMolecule(at: &middle, with: molecule)
+            return replacedMolecule
+        }
+        var replacedMolecule: MoleculeModelProtocol?
+        if try replaceChildMolecule(at: &middle, with: molecule, replaced: &replacedMolecule) {
+            return replacedMolecule
+        }
+        return nil
     }
     
     //--------------------------------------------------

MVMCoreUI/Atomic/Templates/ThreeLayerTemplate.swift

@@ -14,9 +14,8 @@ import UIKit
     // MARK: - Lifecycle
     //--------------------------------------------------
     
-    open override func parsePageJSON() throws {
+    open override func parsePageJSON(loadObject: MVMCoreLoadObject) throws -> PageModelProtocol {
-        try parseTemplate(json: loadObject?.pageJSON)
+        return try parseTemplate(loadObject: loadObject)
-        try super.parsePageJSON()
     }
     
     open override func updateUI(for molecules: [MoleculeModelProtocol]? = nil) {

MVMCoreUI/BaseControllers/ViewController.swift

@@ -40,6 +40,7 @@ import MVMCore
     public var needsUpdateUI = false
     private var observingForResponses: NSObjectProtocol?
     private var initialLoadFinished = false
+    public var isFirstRender = true
     public var previousScreenSize = CGSize.zero
     
     public var selectedField: UIView?
@@ -65,7 +66,9 @@ import MVMCore
               (pagesToListenFor()?.count ?? 0 > 0 || modulesToListenFor()?.count ?? 0 > 0)
         else { return }
         
-        observingForResponses = NotificationCenter.default.addObserver(forName: NSNotification.Name(rawValue: NotificationResponseLoaded), object: nil, queue: pageUpdateQueue, using: responseJSONUpdated(notification:))
+        observingForResponses = NotificationCenter.default.addObserver(forName: NSNotification.Name(rawValue: NotificationResponseLoaded), object: nil, queue: pageUpdateQueue) { [weak self] notification in
+            self?.responseJSONUpdated(notification: notification)
+        }
     }
     
     open func stopObservingForResponseJSONUpdates() {
@@ -81,14 +84,16 @@ import MVMCore
     
     open func modulesToListenFor() -> [String]? {
         let requestModules = loadObject?.requestParameters?.allModules() ?? []
-        let behaviorModules = behaviors?.flatMap { $0.modulesToListenFor() } ?? []
+        let behaviorModules = behaviors?.flatMap { $0.modulesToListenFor } ?? []
         return requestModules + behaviorModules
     }
     
     @objc open func responseJSONUpdated(notification: Notification) {
         // Checks for a page we are listening for.
-        var newData = false
+        var hasDataUpdate = false
+        var pageModel: PageModelProtocol? = nil
         if let pagesLoaded = notification.userInfo?.optionalDictionaryForKey(KeyPageMap),
+           let loadObject,
            let pageType = pagesToListenFor()?.first(where: { (pageTypeListened) -> Bool in
             guard let page = pagesLoaded.optionalDictionaryForKey(pageTypeListened),
                   let pageType = page.optionalStringForKey(KeyPageType),
@@ -97,8 +102,17 @@ import MVMCore
             
             return true
            }) {
-            newData = true
+            hasDataUpdate = true
-            loadObject?.pageJSON = pagesLoaded.optionalDictionaryForKey(pageType)
+            loadObject.pageJSON = pagesLoaded.optionalDictionaryForKey(pageType)
+            
+            // Separate page updates from the module updates to avoid unecessary resets to behaviors and full re-renders.
+            do {
+                pageModel = try parsePageJSON(loadObject: loadObject)
+            } catch {
+                if let coreError = MVMCoreErrorObject.createErrorObject(for: error, location: "updateJSON for pageType: \(String(describing: pageType))") {
+                    MVMCoreLoggingHandler.shared()?.addError(toLog: coreError)
+                }
+            }
         }
         
         // Checks for modules we are listening for.
@@ -106,7 +120,7 @@ import MVMCore
            let modulesListened = modulesToListenFor() {
             for moduleName in modulesListened {
                 if let module = modulesLoaded.optionalDictionaryForKey(moduleName) {
-                    newData = true
+                    hasDataUpdate = true
                     var currentModules = loadObject?.modulesJSON ?? [:]
                     currentModules.updateValue(module, forKey: moduleName)
                     loadObject?.modulesJSON = currentModules
@@ -114,21 +128,11 @@ import MVMCore
             }
         }
         
-        guard newData else { return }
+        guard hasDataUpdate else { return }
         
-        do {
+        MVMCoreDispatchUtility.performBlock(onMainThread: {
-            // TODO: Parse parsePageJSON modifies the page model on a different thread than
+            self.handleNewData(pageModel)
-            // the UI update which could cause discrepancies. Parse should return the resulting
+        })
-            // object and assignment should be synchronized on handleNewData(model: ).
-            try parsePageJSON()
-            MVMCoreDispatchUtility.performBlock(onMainThread: {
-                self.handleNewData()
-            })
-        } catch {
-            if let coreError = MVMCoreErrorObject.createErrorObject(for: error, location: "updateJSON for pageType: \(String(describing: pageType))") {
-                MVMCoreLoggingHandler.shared()?.addError(toLog: coreError)
-            }
-        }
     }
     
     open func shouldFinishProcessingLoad(_ loadObject: MVMCoreLoadObject, error: AutoreleasingUnsafeMutablePointer<MVMCoreErrorObject?>) -> Bool {
@@ -140,7 +144,12 @@ import MVMCore
         
         // Parse the model for the page.
         do {
-            try parsePageJSON()
+            let template = try parsePageJSON(loadObject: loadObject)
+            pageModel = template // TODO: Eventually this page parsing should be done outside of this class and then set by the caller. For now, double duty.
+            isFirstRender = true // Assuming this is only on the first page load from the handler. Might need to revist later.
+            if let backgroundRequest = loadObject.requestParameters?.backgroundRequest, !backgroundRequest, let pageType, let identifier = loadObject.identifier {
+                MVMCoreLoggingHandler.shared()?.logCoreEvent(.pageProcessingComplete(pageType: pageType, requestUUID: identifier, webUrl: nil))
+            }
         } catch let parsingError {
             // Log all parsing errors and fail load.
             if let errorObject = MVMCoreLoadHandler.sharedGlobal()?.error(for: loadObject, causedBy: parsingError) {
@@ -180,10 +189,8 @@ import MVMCore
         return "Error parsing template. \((parsingError as NSError).localizedFailureReason ?? parsingError.localizedDescription)"
     }
     
-    open func parsePageJSON() throws {
+    open func parsePageJSON(loadObject: MVMCoreLoadObject) throws -> PageModelProtocol {
-        if let backgroundRequest = loadObject?.requestParameters?.backgroundRequest, !backgroundRequest, let pageType, let identifier = loadObject?.identifier {
+        throw MVMCoreError.error(code: ErrorCode.parsingJSON.rawValue, messageToDisplay: "Template needs to define its model!", messageToLog: "Template needs to define its model!")
-            MVMCoreLoggingHandler.shared()?.logCoreEvent(.pageProcessingComplete(pageType: pageType, requestUUID: identifier, webUrl: nil))
-        }
     }
     
     open class func verifyRequiredModulesLoaded(for loadObject: MVMCoreLoadObject?, error: AutoreleasingUnsafeMutablePointer<MVMCoreErrorObject?>) -> Bool {
@@ -218,38 +225,85 @@ import MVMCore
         return navigationModel
     }
     
-    /// Processes any new data. Called after the page is loaded the first time and on response updates for this page, Triggers a render refresh.
+    /// Processes any new data. Called after the page is loaded the first time and on response updates for this page. Triggers a render refresh.
     @MainActor
-    open func handleNewData() {
+    open func handleNewData(_ pageModel: PageModelProtocol? = nil) {
-        if model?.navigationBar == nil {
+        
+        guard var newPageModel = pageModel ?? self.pageModel else { return }
+        let originalModel = isFirstRender ? nil : self.pageModel as? MVMControllerModelProtocol
+        
+        // Refresh our behaviors if there is a page change.
+        if let behaviorContainer = newPageModel as? (PageBehaviorContainerModelProtocol & TemplateModelProtocol),
+            (originalModel == nil || originalModel!.id != behaviorContainer.id) {
+            var behaviorHandler = self
+            behaviorHandler.applyBehaviors(pageBehaviorModel: behaviorContainer)
+        }
+        
+        // Setup the default navigation bar if it is missing.
+        if newPageModel.navigationBar == nil {
             let navigationItem = createDefaultLegacyNavigationModel()
-            model?.navigationBar = navigationItem
+            newPageModel.navigationBar = navigationItem
         }
         
-        executeBehaviors { (behavior: PageMoleculeTransformationBehavior) in
+        // Make the template available for onPageNew behavior handling. See if we can have behaviors rely on roots later.
-            behavior.onPageNew(rootMolecules: getRootMolecules(), delegateObjectIVar)
+        self.pageModel = newPageModel
+        
+        // Run through behavior tranformations.
+        var behaviorUpdatedModels = [MoleculeModelProtocol]()
+        if var newTemplateModel = newPageModel as? TemplateModelProtocol {
+            behaviorUpdatedModels = runBehaviorTransformations(on: &newTemplateModel)
         }
         
-        if formValidator == nil {
+        // Apply the form validator to the controller.
-            let rules = model?.formRules
+        if formValidator == nil { // TODO: Can't change form rules?
+            let rules = (newPageModel as? FormHolderModelProtocol)?.formRules
             formValidator = FormValidator(rules)
         }
         
-        updateUI()
+        // Reset after tranformations.
+        self.pageModel = newPageModel
+        
+        // Run through the differences between separate page model trees.
+        var pageUpdatedModels = [MoleculeModelProtocol]()
+        if let originalModel, // We had a prior.
+           let newPageModel = newPageModel as? TemplateModelProtocol,
+           originalModel.id != newPageModel.id {
+            // This isn't ready yet. handleNewData for the ListTemplate triggers a row item reset and full rebuild + StackTemplate isn't targeting individual refreshes anyway.
+//            pageUpdatedModels = originalModel.findAllTheirsNotEqual(against: newPageModel)
+//            debugLog("Page molecule updates\n\(pageUpdatedModels)")
+            isFirstRender = true // Instead force a full render whenever there is a page data change.
+        }
+        
+        let allUpdatedMolecules = behaviorUpdatedModels //+ pageUpdatedModels
         
         // Notify the manager of new data.
         // Warning: Some flows cause table reloads. Until the UI update is decoupled, should be after the updateUI.
         manager?.newDataReceived?(in: self)
+        
+        // Dispatch to decouple execution. First massage data through template classes, then render.
+        Task { @MainActor in
+            
+            if allUpdatedMolecules.isEmpty || isFirstRender {
+                debugLog("Performing full page render...")
+                updateUI()
+            } else {
+                debugLog("Performing partial render of \(allUpdatedMolecules) molecules...")
+                updateUI(for: allUpdatedMolecules)
+            }
+        }
     }
     
     /// Applies the latest model to the UI.
     open func updateUI(for molecules: [MoleculeModelProtocol]? = nil) {
-        guard molecules == nil else { return }
+        
+        isFirstRender = false
         
         executeBehaviors { (behavior: PageMoleculeTransformationBehavior) in
-            behavior.willRender(rootMolecules: getRootMolecules(), delegateObjectIVar)
+            behavior.willRender(rootMolecules: molecules ?? getRootMolecules(), delegateObjectIVar)
         }
         
+        guard molecules == nil else { return }
+        
         if let backgroundColor = model?.backgroundColor {
             view.backgroundColor = backgroundColor.uiColor
         }
@@ -258,6 +312,31 @@ import MVMCore
         view.setNeedsLayout()
     }
     
+    func runBehaviorTransformations(on newTemplateModel: inout any TemplateModelProtocol) -> [any MoleculeModelProtocol] {
+        var behaviorUpdatedModels = [MoleculeModelProtocol]()
+        executeBehaviors { (behavior: PageMoleculeTransformationBehavior) in
+            var changes = [any MoleculeModelProtocol]()
+            if let updatedMolecules = behavior.onPageNew(rootMolecules: newTemplateModel.rootMolecules, delegateObjectIVar, changes: &changes) {
+                updatedMolecules.forEach { molecule in
+                    // Replace again in case there is a template level child.
+                    if let replaced = try? newTemplateModel.replaceChildMolecule(with: molecule) {
+                        // Only recognize the molecules that actually changed.
+                        if changes.count > 0 {
+                            debugLog("\(behavior) updated \(changes) in template model.")
+                            changes = changes.filter({ model in
+                                !behaviorUpdatedModels.contains { $0.id == model.id }
+                            })
+                            behaviorUpdatedModels.append(contentsOf: changes)
+                        }
+                    } else {
+                        debugLog("Failed to replace \(molecule) in the template model.")
+                    }
+                }
+            }
+        }
+        return behaviorUpdatedModels
+    }
+    
     public func generateMoleculeView(from model: MoleculeModelProtocol) -> MoleculeViewProtocol? {
         executeBehaviors { (behavior: PageMoleculeTransformationBehavior) in
             behavior.willSetupMolecule(with: model, updating: nil)
@@ -310,7 +389,7 @@ import MVMCore
         super.viewDidLoad()
         
         // Do any additional setup after loading the view.
-        MVMCoreLoggingHandler.logDebugMessage(withDelegate: "View Controller Loaded : \(self)")
+        debugLog("View Controller Loaded")
         
         // We use our own margins.
         viewRespectsSystemMinimumLayoutMargins = false
@@ -324,7 +403,7 @@ import MVMCore
             initialLoad()
         }
         
-        handleNewData()
+        handleNewData(pageModel) // Set outside shouldFinishProcessingLoad.
     }
     
     open override func viewDidLayoutSubviews() {
@@ -393,7 +472,7 @@ import MVMCore
     
     deinit {
         stopObservingForResponseJSONUpdates()
-        MVMCoreLoggingHandler.logDebugMessage(withDelegate: "View Controller Deallocated : \(self)")
+        debugLog("Deallocated")
     }
     
     open override var supportedInterfaceOrientations: UIInterfaceOrientationMask {
@@ -511,41 +590,6 @@ import MVMCore
     // Needed otherwise when subclassed, the extension gets called.
     open func moleculeLayoutUpdated(_ molecule: MoleculeViewProtocol) { }
     
-    public func replaceMoleculeData(_ moleculeModels: [MoleculeModelProtocol], completionHandler: (([MoleculeModelProtocol])->Void)? = nil) {
-        pageUpdateQueue.addOperation {
-            let replacedModels:[MoleculeModelProtocol] = moleculeModels.compactMap { model in
-                guard self.attemptToReplace(with: model) else {
-                    return nil
-                }
-                return model
-            }
-            if replacedModels.count > 0 {
-                DispatchQueue.main.sync {
-                    self.updateUI(for: replacedModels)
-                }
-            }
-            completionHandler?(replacedModels)
-        }
-    }
-    
-    open func attemptToReplace(with replacementModel: MoleculeModelProtocol) -> Bool {
-        guard var templateModel = getTemplateModel() else { return false }
-        var didReplace = false
-        do {
-            didReplace = try templateModel.replaceMolecule(with: replacementModel)
-            if !didReplace {
-                MVMCoreLoggingHandler.shared()?.addError(toLog: MVMCoreErrorObject(title: nil, messageToLog: "Failed to find '\(replacementModel.id)' in the current screen.", code: ErrorCode.viewControllerProcessingJSON.rawValue, domain: ErrorDomainSystem, location: String(describing: type(of: self)))!)
-            }
-        } catch {
-            let coreError = MVMCoreErrorObject.createErrorObject(for: error, location: String(describing: type(of: self)))!
-            if let error = error as? HumanReadableDecodingErrorProtocol {
-                coreError.messageToLog = "Error replacing molecule \"\(replacementModel.id)\": \(error.readableDescription)"
-            }
-            MVMCoreLoggingHandler.shared()?.addError(toLog: coreError)
-        }
-        return didReplace
-    }
-    
     //--------------------------------------------------
     // MARK: - MVMCoreUIDetailViewProtocol
     //--------------------------------------------------
@@ -658,3 +702,15 @@ import MVMCore
         }
     }
 }
+
+extension ViewController: CoreLogging {
+    
+    public var loggingPrefix: String {
+        "\(self) \(pageType ?? ""): "
+    }
+    
+    public static var loggingCategory: String? {
+        return "Rendering"
+    }
+    
+}

MVMCoreUI/Behaviors/AddRemoveMoleculeBehavior.swift

@@ -159,6 +159,13 @@ public class AddMoleculesActionModel: ActionModelProtocol {
         extraParameters = try typeContainer.decodeIfPresent(JSONValueDictionary.self, forKey: .extraParameters)
         analyticsData = try typeContainer.decodeIfPresent(JSONValueDictionary.self, forKey: .analyticsData)
     }
+    
+    public func isEqual(to model: any ModelComparisonProtocol) -> Bool {
+        guard let model = model as? Self else { return false }
+        return model.extraParameters == extraParameters
+        && model.analyticsData == analyticsData
+        && model.animation == animation
+    }
 }
 
 public class RemoveMoleculesActionModel: ActionModelProtocol {
@@ -186,6 +193,13 @@ public class RemoveMoleculesActionModel: ActionModelProtocol {
         extraParameters = try typeContainer.decodeIfPresent(JSONValueDictionary.self, forKey: .extraParameters)
         analyticsData = try typeContainer.decodeIfPresent(JSONValueDictionary.self, forKey: .analyticsData)
     }
+    
+    public func isEqual(to model: any ModelComparisonProtocol) -> Bool {
+        guard let model = model as? Self else { return false }
+        return model.extraParameters == extraParameters
+        && model.analyticsData == analyticsData
+        && model.animation == animation
+    }
 }
 
 public class SwapMoleculesActionModel: ActionModelProtocol {
@@ -213,4 +227,11 @@ public class SwapMoleculesActionModel: ActionModelProtocol {
         extraParameters = try typeContainer.decodeIfPresent(JSONValueDictionary.self, forKey: .extraParameters)
         analyticsData = try typeContainer.decodeIfPresent(JSONValueDictionary.self, forKey: .analyticsData)
     }
+    
+    public func isEqual(to model: any ModelComparisonProtocol) -> Bool {
+        guard let model = model as? Self else { return false }
+        return model.extraParameters == extraParameters
+        && model.analyticsData == analyticsData
+        && model.animation == animation
+    }
 }

MVMCoreUI/Behaviors/GetContactBehavior.swift

@@ -20,6 +20,12 @@ public class PageGetContactBehaviorModel: PageBehaviorModelProtocol {
     public var shouldAllowMultipleInstances: Bool { false }
     
     public init() { }
+    
+    // Default
+    // public func isEqual(to model: any MVMCore.ModelComparisonProtocol) -> Bool {
+    //    guard let model = model as? Self else { return false }
+    //    return behaviorName == model.behaviorName
+    //}
 }
 
 public class PageGetContactBehavior: PageVisibilityBehavior {

MVMCoreUI/Behaviors/GetNotificationAuthStatusBehavior.swift

@@ -15,6 +15,12 @@ public class GetNotificationAuthStatusBehaviorModel: PageBehaviorModelProtocol {
     public var shouldAllowMultipleInstances: Bool { false }
     
     public init() { }
+    
+    // Default
+    // public func isEqual(to model: any ModelComparisonProtocol) -> Bool {
+    //    guard let model = model as? Self else { return false }
+    //    return behaviorName == model.behaviorName
+    //}
 }
 
 public class GetNotificationAuthStatusBehavior: PageVisibilityBehavior {

MVMCoreUI/Behaviors/PollingBehaviorModel.swift

@@ -8,6 +8,7 @@
 
 import Foundation
 import MVMCore
+import Combine
 
 public class PollingBehaviorModel: PageBehaviorModelProtocol {
     public class var identifier: String { "pollingBehavior" }
@@ -45,20 +46,38 @@ public class PollingBehaviorModel: PageBehaviorModelProtocol {
         try container.encode(refreshOnFirstLoad, forKey: .refreshOnFirstLoad)
         try container.encode(refreshOnShown, forKey: .refreshOnShown)
     }
+    
+    public func isEqual(to model: any ModelComparisonProtocol) -> Bool {
+        guard let model = model as? Self else { return false }
+        return runWhileHidden == model.runWhileHidden
+        && refreshOnShown == model.refreshOnShown
+        && refreshOnFirstLoad == model.refreshOnFirstLoad
+        && refreshInterval == model.refreshInterval
+        && refreshAction.isEqual(to: model.refreshAction)
+    }
 }
 
-public class PollingBehavior: NSObject, PageVisibilityBehavior {
+extension PollingBehaviorModel: CustomDebugStringConvertible {
+    public var debugDescription: String {
+        return "\(Self.self) @ \(refreshInterval) firing \(self.refreshAction)"
+    }
+}
+
+public class PollingBehavior: NSObject, PageVisibilityBehavior, PageMoleculeTransformationBehavior, CoreLogging {
+    
+    public static var loggingCategory: String? { return String(describing: Self.self) }
     
     var model: PollingBehaviorModel
     var delegateObject: MVMCoreUIDelegateObject?
-    var lastRefresh = Date.distantPast
+    var lastRefresh = Date() // Treat the last refresh as now on init. refreshOnShown will bypass otherwise.
     var pollTimer: DispatchSourceTimer?
+    var backgroundEventSubscripiton: AnyCancellable?
     
     var remainingTimeToRefresh: TimeInterval {
-        lastRefresh.timeIntervalSinceNow - model.refreshInterval
+         model.refreshInterval + lastRefresh.timeIntervalSinceNow // timeIntervalSinceNow in negative since earlier recording (--)
     }
     
-    var firstTimeLoad = true
+    var firstTimeLoad = true // TODO: Model replacement is probably going to impact this. Need to transfer first load state.
     
     var refreshOnShown: Bool {
         if model.refreshOnFirstLoad && firstTimeLoad {
@@ -71,6 +90,15 @@ public class PollingBehavior: NSObject, PageVisibilityBehavior {
     public required init(model: PageBehaviorModelProtocol, delegateObject: MVMCoreUIDelegateObject?) {
         self.model = model as! PollingBehaviorModel
         self.delegateObject = delegateObject
+        Self.debugLog("Initializing for \(model)")
+    }
+    
+    public func onPageNew(rootMolecules: [any MoleculeModelProtocol], _ delegateObject: MVMCoreUIDelegateObject?) -> [MoleculeModelProtocol]? {
+        if let behaviorVC = delegateObject?.moleculeDelegate as? ViewController, MVMCoreUIUtility.getCurrentVisibleController() == behaviorVC {
+            // If behavior is initialized after the page is shown, we need to start the timer. Don't immediately start an action. That is triggered by onPageShown if its a fresh view.
+            resumePollingTimer(withRemainingTime: remainingTimeToRefresh, refreshAction: model.refreshAction, interval: model.refreshInterval)
+        }
+        return nil
     }
 
     public func onPageShown(_ delegateObject: MVMCoreUIDelegateObject?) {
@@ -79,26 +107,47 @@ public class PollingBehavior: NSObject, PageVisibilityBehavior {
     
     public func onPageHidden(_ delegateObject: MVMCoreUIDelegateObject?) {
         pollTimer?.cancel()
+        backgroundEventSubscripiton = nil
     }
     
     func resumePollingTimer(withRemainingTime timeRemaining: TimeInterval, refreshAction: ActionModelProtocol, interval: TimeInterval) {
         let delegateObject = delegateObject
         pollTimer?.cancel()
+        let pollingId = UUID().uuidString
+        debugLog("Scheduling timed event \(pollingId) in \(timeRemaining), interval: \(interval)")
         pollTimer = DispatchSource.makeTimerSource()
         pollTimer?.schedule(deadline: .now() + timeRemaining, repeating: interval)
-        pollTimer?.setEventHandler(qos:.utility) {
+        pollTimer?.setEventHandler(qos:.utility) { [weak self] in
-            Task {
+            guard let self = self else { return }
+            lastRefresh = Date()
+            Task { [weak self] in
+                self?.debugLog("Firing timed event \(pollingId), \(refreshAction)")
                 if let delegateActionHandler = delegateObject?.actionDelegate as? ActionDelegateProtocol {
                     try? await delegateActionHandler.performAction(with: refreshAction, additionalData: nil, delegateObject: delegateObject)
                 } else {
                     try? await MVMCoreActionHandler.shared()?.handleAction(with: refreshAction, additionalData: nil, delegateObject: delegateObject)
                 }
+                self?.debugLog("Finished timed event \(pollingId)")
             }
         }
         pollTimer?.resume()
+        setupBackgroundingPause()
+    }
+    
+    private func setupBackgroundingPause() {
+        backgroundEventSubscripiton = NotificationCenter.default.publisher(for: UIApplication.didEnterBackgroundNotification).sink { [weak self] _ in
+            guard let self = self else { return }
+            pollTimer?.cancel()
+            
+            backgroundEventSubscripiton = NotificationCenter.default.publisher(for: UIApplication.didBecomeActiveNotification).sink { [weak self] _ in
+                guard let self = self else { return }
+                resumePollingTimer(withRemainingTime: remainingTimeToRefresh, refreshAction: model.refreshAction, interval: model.refreshInterval)
+            }
+        }
     }
     
     deinit {
+        debugLog("deinit")
         pollTimer?.cancel()
     }
 }

MVMCoreUI/Behaviors/Protocols/PageBehaviorHandlerProtocol.swift

@@ -33,6 +33,7 @@ public extension PageBehaviorHandlerProtocol {
     mutating func applyBehaviors(pageBehaviorModel: PageBehaviorContainerModelProtocol, delegateObject: MVMCoreUIDelegateObject?) {
         // Pull the existing behaviors.
         var behaviors = (behaviors ?? []).filter { $0.transcendsPageUpdates }
+        
         // Create and append any new behaviors based on the incoming models.
         let newBehaviors = createBehaviors(for: pageBehaviorModel.behaviors ?? [], delegateObject: delegateObject)
         behaviors.append(contentsOf: newBehaviors)

MVMCoreUI/Behaviors/Protocols/PageBehaviorModelProtocol.swift

@@ -33,4 +33,9 @@ public extension PageBehaviorModelProtocol {
     static var categoryName: String {
         "\(PageBehaviorModelProtocol.self)"
     }
+    
+    func isEqual(to model: any ModelComparisonProtocol) -> Bool {
+        guard let model = model as? Self else { return false }
+        return behaviorName == model.behaviorName
+    }
 }