Merge branch 'release/2.0.6'

Instead of allocating new dictionaries for the scope elements, the scope
checks are just unrolled in-place. Now we have 6 almost identical methods
that differ only in the inline-check-method. Not optimal but minimal
memory and performance penalty.

This should reduce memory consumption and increase the performance
while parsing, see issue #10

.jazzy.yaml

@@ -1,5 +1,5 @@
 module: HTMLKit
-module_version: 2.0.4
+module_version: 2.0.6
 author: Iskandar Abudiab 
 author_url: https://twitter.com/iabudiab
 github_url: https://github.com/iabudiab/HTMLKit

.travis.yml

@@ -1,5 +1,5 @@
 language: objective-c
-osx_image: xcode8.2
+osx_image: xcode8.3
 
 branches:
   except:
@@ -17,21 +17,19 @@ env:
     - MACOS_FRAMEWORK_SCHEME=HTMLKit-macOS
     - WATCHOS_FRAMEWORK_SCHEME="HTMLKit-watchOS"
     - TVOS_FRAMEWORK_SCHEME="HTMLKit-tvOS"
-    - IOS_SDK=iphonesimulator10.2
+    - IOS_SDK=iphonesimulator10.3
     - MACOS_SDK=macosx10.12
-    - WATCHOS_SDK=watchsimulator3.1
-    - TVOS_SDK=appletvsimulator10.1
+    - WATCHOS_SDK=watchsimulator3.2
+    - TVOS_SDK=appletvsimulator10.2
   matrix:
     - DESTINATION="arch=x86_64"                              SIMULATOR=""                                   SCHEME="$MACOS_FRAMEWORK_SCHEME"    SDK="$MACOS_SDK"
-    - DESTINATION="OS=9.0,name=iPhone 6"                     SIMULATOR="iPhone 6 (9.0)"                     SCHEME="$IOS_FRAMEWORK_SCHEME"      SDK="$IOS_SDK"
-    - DESTINATION="OS=9.1,name=iPhone 6 Plus"                SIMULATOR="iPhone 6 Plus (9.1)"                SCHEME="$IOS_FRAMEWORK_SCHEME"      SDK="$IOS_SDK"
-    - DESTINATION="OS=9.2,name=iPhone 6S"                    SIMULATOR="iPhone 6S (9.2)"                    SCHEME="$IOS_FRAMEWORK_SCHEME"      SDK="$IOS_SDK"
+    - DESTINATION="OS=8.4,name=iPhone 6 Plus"                SIMULATOR="iPhone 6 Plus (8.4)"                SCHEME="$IOS_FRAMEWORK_SCHEME"      SDK="$IOS_SDK"
     - DESTINATION="OS=9.3,name=iPhone 6S Plus"               SIMULATOR="iPhone 6S Plus (9.3)"               SCHEME="$IOS_FRAMEWORK_SCHEME"      SDK="$IOS_SDK"
-    - DESTINATION="OS=10.1,name=iPhone 7 Plus"               SIMULATOR="iPhone 7 Plus (10.1)"               SCHEME="$IOS_FRAMEWORK_SCHEME"      SDK="$IOS_SDK"
+    - DESTINATION="OS=10.3,name=iPhone 7 Plus"               SIMULATOR="iPhone 7 Plus (10.3)"               SCHEME="$IOS_FRAMEWORK_SCHEME"      SDK="$IOS_SDK"
     - DESTINATION="OS=2.2,name=Apple Watch - 42mm"           SIMULATOR="Apple Watch - 42mm (2.2)"           SCHEME="$WATCHOS_FRAMEWORK_SCHEME"  SDK="$WATCHOS_SDK"
-    - DESTINATION="OS=3.1,name=Apple Watch Series 2 - 42mm"  SIMULATOR="Apple Watch Series 2 - 42mm (3.1)"  SCHEME="$WATCHOS_FRAMEWORK_SCHEME"  SDK="$WATCHOS_SDK"
-    - DESTINATION="OS=9.0,name=Apple TV 1080p"               SIMULATOR="Apple TV 1080p (9.2)"               SCHEME="$TVOS_FRAMEWORK_SCHEME"     SDK="$TVOS_SDK"
-    - DESTINATION="OS=10.0,name=Apple TV 1080p"              SIMULATOR="Apple TV 1080p (10.0)"              SCHEME="$TVOS_FRAMEWORK_SCHEME"     SDK="$TVOS_SDK"
+    - DESTINATION="OS=3.2,name=Apple Watch Series 2 - 42mm"  SIMULATOR="Apple Watch Series 2 - 42mm (3.2)"  SCHEME="$WATCHOS_FRAMEWORK_SCHEME"  SDK="$WATCHOS_SDK"
+    - DESTINATION="OS=9.2,name=Apple TV 1080p"               SIMULATOR="Apple TV 1080p (9.2)"               SCHEME="$TVOS_FRAMEWORK_SCHEME"     SDK="$TVOS_SDK"
+    - DESTINATION="OS=10.2,name=Apple TV 1080p"              SIMULATOR="Apple TV 1080p (10.2)"              SCHEME="$TVOS_FRAMEWORK_SCHEME"     SDK="$TVOS_SDK"
 
 script:
   - set -o pipefail

CHANGELOG.md

@@ -1,14 +1,47 @@
 # Change Log
 
+## [2.0.6](https://github.com/iabudiab/HTMLKit/releases/tag/2.0.6) 
+
+Released on 2017.05.02
+
+### Added
+
+- Memory consumption improvements (issue #10)
+	- Allocate `childNodes` collection in `HTMLNode` only when inserting child nodes
+	- Replace `NSStringFromSelector` calls with constants in `HTMLNode` validations
+	- Improve `reverseObjectEnumerator` usage while parsing HTML
+	- Rewrite internal logic of the `HTMLStackOfOpenElements` to prevent excessive allocations
+
+
+## [2.0.5](https://github.com/iabudiab/HTMLKit/releases/tag/2.0.5) 
+
+Released on 2017.04.19
+
+### Fixed
+
+- Xcode 8.3 issue with modulemaps
+	- Temporary workaround (renamed modulemap file)
+- Memory Leaks in `CSSInputStream`
+
+### Added
+
+- Minor memory consumption improvements
+	- Collections for child nodes or attributes of HTML Nodes or Elements are allocated lazily
+	- Underyling data string of `CharacterData` is allocated on first access
+	- Autorelease pool for the main `HTMLTokenizer` loop
+
+
 ## [2.0.4](https://github.com/iabudiab/HTMLKit/releases/tag/2.0.4) 
 
 Released on 2017.04.2
 
 ### Fixed
+
 - Testing with Swift 3.1
 	- Fixed by @tali in PR #8
 
 ### Deprecated
+
 - `HTMLRange` initializers with typo
 	- `initWithDowcument:startContainer:startOffset:endContainer:endOffset:`
 
@@ -18,6 +51,7 @@ Released on 2017.04.2
 Released on 2017.03.6
 
 ### Fixed
+
 - Compilation for Swift 3.1
 	- Fixed by @tali in PR #6
 
@@ -27,6 +61,7 @@ Released on 2017.03.6
 Released on 2017.02.26
 
 ### Fixed
+
 - Retain cycles in `HTMLNodeIterator` (issue #4)
 - Retain cycles in `HTMLRange` (issue #5)
 - The layout of `HTMLKit` tests module for Swift Package Manager

HTMLKit.podspec

@@ -1,6 +1,6 @@
 Pod::Spec.new do |s|
   s.name               = "HTMLKit"
-  s.version            = "2.0.4"
+  s.version            = "2.0.6"
   s.summary            = "HTMLKit, an Objective-C framework for your everyday HTML needs."
   s.license            = "MIT"
   s.homepage           = "https://github.com/iabudiab/HTMLKit"

Sources/CSSInputStream.m

@@ -24,14 +24,14 @@
 
 - (NSString *)consumeIdentifier
 {
-	CFMutableStringRef value = CFStringCreateMutable(kCFAllocatorDefault, 0);
-
 	if (!isValidIdentifierStart([self inputCharacterPointAtOffset:0],
 								[self inputCharacterPointAtOffset:1],
 								[self inputCharacterPointAtOffset:2])) {
 		return nil;
 	}
 
+	CFMutableStringRef value = CFStringCreateMutable(kCFAllocatorDefault, 0);
+
 	while (YES) {
 		UTF32Char codePoint = [self consumeNextInputCharacter];
 		if (codePoint == EOF) {
@@ -47,7 +47,12 @@
 		}
 	}
 
-	return (__bridge NSString *)(CFStringGetLength(value) > 0 ? value : nil);
+	if (CFStringGetLength(value) > 0) {
+		return (__bridge_transfer NSString *)value;
+	}
+
+	CFRelease(value);
+	return nil;
 }
 
 - (NSString *)consumeStringWithEndingCodePoint:(UTF32Char)endingCodePoint
@@ -85,7 +90,12 @@
 		}
 	}
 
-	return (__bridge NSString *)(CFStringGetLength(value) > 0 ? value : nil);
+	if (CFStringGetLength(value) > 0) {
+		return (__bridge_transfer NSString *)value;
+	}
+
+	CFRelease(value);
+	return nil;
 }
 
 - (UTF32Char)consumeEscapedCodePoint
@@ -105,7 +115,7 @@
 			[self consumeNextInputCharacter];
 		}
 
-		NSScanner *scanner = [NSScanner scannerWithString:(__bridge NSString *)(hexString)];
+		NSScanner *scanner = [NSScanner scannerWithString:(__bridge_transfer NSString *)(hexString)];
 		unsigned int number;
 		[scanner scanHexInt:&number];
 

Sources/HTMLCharacterData.m

@@ -24,14 +24,25 @@
 {
 	self = [super initWithName:name type:type];
 	if (self) {
-		_data = [[NSMutableString alloc] initWithString:data ?: @""];
+		if (data) {
+			_data = [[NSMutableString alloc] initWithString:data];
+		}
 	}
 	return self;
 }
 
+- (NSString *)data
+{
+	if (_data == nil) {
+		_data = [[NSMutableString alloc] initWithString:@""];
+	}
+
+	return _data;
+}
+
 - (NSString *)textContent
 {
-	return [_data copy];
+	return [self.data copy];
 }
 
 - (void)setTextContent:(NSString *)textContent
@@ -41,7 +52,7 @@
 
 - (NSUInteger)length
 {
-	return _data.length;
+	return self.data.length;
 }
 
 #pragma mark - Data
@@ -81,7 +92,7 @@ NS_INLINE void CheckValidOffset(HTMLCharacterData *node, NSUInteger offset, NSSt
 
 	range.length = MIN(range.length, self.length - range.location);
 
-	[_data replaceCharactersInRange:range withString:data];
+	[(NSMutableString *)self.data replaceCharactersInRange:range withString:data];
 	[self.ownerDocument didRemoveCharacterDataInNode:self atOffset:range.location withLength:range.length];
 	[self.ownerDocument didAddCharacterDataToNode:self atOffset:range.location withLength:data.length];
 }

Sources/HTMLElement.m

@@ -32,7 +32,7 @@
 
 - (instancetype)initWithTagName:(NSString *)tagName
 {
-	return [self initWithTagName:tagName attributes:@{}];
+	return [self initWithTagName:tagName attributes:nil];
 }
 
 - (instancetype)initWithTagName:(NSString *)tagName attributes:(NSDictionary *)attributes
@@ -45,8 +45,9 @@
 	self = [super initWithName:tagName type:HTMLNodeElement];
 	if (self) {
 		_tagName = [tagName copy];
-		_attributes = [HTMLOrderedDictionary new];
+		_attributes = nil;
 		if (attributes != nil) {
+			_attributes = [HTMLOrderedDictionary new];
 			[_attributes addEntriesFromDictionary:attributes];
 		}
 		_htmlNamespace = htmlNamespace;
@@ -56,24 +57,33 @@
 
 #pragma mark - Special Attributes
 
+- (NSMutableDictionary<NSString *,NSString *> *)attributes
+{
+	if (_attributes == nil) {
+		_attributes = [HTMLOrderedDictionary new];
+	}
+
+	return _attributes;
+}
+
 - (NSString *)elementId
 {
-	return _attributes[@"id"] ?: @"";
+	return self.attributes[@"id"] ?: @"";
 }
 
 - (void)setElementId:(NSString *)elementId
 {
-	_attributes[@"id"] = elementId;
+	self.attributes[@"id"] = elementId;
 }
 
 - (NSString *)className
 {
-	return _attributes[@"class"] ?: @"";
+	return self.attributes[@"class"] ?: @"";
 }
 
 - (void)setClassName:(NSString *)className
 {
-	_attributes[@"class"] = className;
+	self.attributes[@"class"] = className;
 }
 
 - (HTMLDOMTokenList *)classList
@@ -85,22 +95,22 @@
 
 - (BOOL)hasAttribute:(NSString *)name
 {
-	return _attributes[name] != nil;
+	return self.attributes[name] != nil;
 }
 
 - (NSString *)objectForKeyedSubscript:(NSString *)name;
 {
-	return _attributes[name];
+	return self.attributes[name];
 }
 
 - (void)setObject:(NSString *)value forKeyedSubscript:(NSString *)attribute
 {
-	_attributes[attribute] = value;
+	self.attributes[attribute] = value;
 }
 
 - (void)removeAttribute:(NSString *)name
 {
-	[_attributes removeObjectForKey:name];
+	[self.attributes removeObjectForKey:name];
 }
 
 - (NSString *)textContent

Sources/HTMLKit-Info.plist

@@ -17,7 +17,7 @@
 	<key>CFBundlePackageType</key>
 	<string>FMWK</string>
 	<key>CFBundleShortVersionString</key>
-	<string>2.0.4</string>
+	<string>2.0.6</string>
 	<key>CFBundleSignature</key>
 	<string>????</string>
 	<key>CFBundleVersion</key>

Sources/HTMLListOfActiveFormattingElements.m

@@ -46,7 +46,7 @@
 - (void)addElement:(HTMLElement *)element
 {
 	NSUInteger existing = 0;
-	for (HTMLElement *node in _list.reverseObjectEnumerator.allObjects) {
+	for (HTMLElement *node in _list.reverseObjectEnumerator) {
 		if ([node isEqual:[HTMLMarker marker]]) {
 			break;
 		}

Sources/HTMLNode.m

@@ -19,6 +19,10 @@
 #import "HTMLDocument+Private.h"
 #import "HTMLDOMUtils.h"
 
+NSString * const ValidationNodePreInsertion = @"-ensurePreInsertionValidityOfNode:beforeChildNode:";
+NSString * const ValidationNodeReplacement = @"-ensureReplacementValidityOfChildNode:withNode:";
+NSString * const RemoveChildNode = @"-removeChildNode:";
+
 @interface HTMLNode ()
 {
 	NSMutableOrderedSet *_childNodes;
@@ -36,13 +40,22 @@
 	if (self) {
 		_name = name;
 		_nodeType = type;
-		_childNodes = [NSMutableOrderedSet new];
+		_childNodes = nil;
 	}
 	return self;
 }
 
 #pragma mark - Properties
 
+- (NSOrderedSet<HTMLNode *> *)childNodes
+{
+	if (_childNodes == nil) {
+		_childNodes = [NSMutableOrderedSet new];
+	}
+
+	return _childNodes;
+}
+
 - (HTMLDocument *)ownerDocument
 {
 	if (_nodeType == HTMLNodeDocument) {
@@ -55,7 +68,9 @@
 - (void)setOwnerDocument:(HTMLDocument *)ownerDocument
 {
 	_ownerDocument = ownerDocument;
-	[self.childNodes.array makeObjectsPerformSelector:@selector(setOwnerDocument:) withObject:ownerDocument];
+	for (HTMLNode *child in _childNodes) {
+		[child setOwnerDocument:ownerDocument];
+	}
 }
 
 - (HTMLNode *)rootNode
@@ -75,12 +90,12 @@
 
 - (HTMLNode *)firstChild
 {
-	return self.childNodes.firstObject;
+	return _childNodes.firstObject;
 }
 
 - (HTMLNode *)lastChild
 {
-	return self.childNodes.lastObject;
+	return _childNodes.lastObject;
 }
 
 - (HTMLNode *)previousSibling
@@ -121,7 +136,7 @@
 
 - (NSUInteger)index
 {
-	return [self.parentNode indexOfChildNode:self];
+	return [_parentNode indexOfChildNode:self];
 }
 
 - (NSString *)textContent
@@ -145,12 +160,16 @@
 
 - (BOOL)hasChildNodes
 {
-	return self.childNodes.count > 0;
+	return _childNodes.count > 0;
 }
 
 - (BOOL)hasChildNodeOfType:(HTMLNodeType)type
 {
-	NSUInteger index = [self.childNodes indexOfObjectPassingTest:^BOOL(id obj, NSUInteger idx, BOOL *stop) {
+	if (_childNodes == nil) {
+		return NO;
+	}
+
+	NSUInteger index = [_childNodes indexOfObjectPassingTest:^BOOL(id obj, NSUInteger idx, BOOL *stop) {
 		if ([(HTMLNode *)obj nodeType] == type) {
 			*stop = YES;
 			return YES;
@@ -163,7 +182,7 @@
 
 - (NSUInteger)childNodesCount
 {
-	return self.childNodes.count;
+	return _childNodes.count;
 }
 
 - (BOOL)isEmpty
@@ -173,25 +192,25 @@
 
 - (HTMLNode *)childNodeAtIndex:(NSUInteger)index
 {
-	return [self.childNodes objectAtIndex:index];
+	return [_childNodes objectAtIndex:index];
 }
 
 - (NSUInteger)childElementsCount
 {
-	return [self.childNodes indexesOfObjectsPassingTest:^BOOL(HTMLNode *  _Nonnull node, NSUInteger idx, BOOL * _Nonnull stop) {
+	return [_childNodes indexesOfObjectsPassingTest:^BOOL(HTMLNode *  _Nonnull node, NSUInteger idx, BOOL * _Nonnull stop) {
 		return node.nodeType == HTMLNodeElement;
 	}].count;
 }
 
 - (NSUInteger)indexOfChildNode:(HTMLNode *)node
 {
-	return [self.childNodes indexOfObject:node];
+	return [_childNodes indexOfObject:node];
 }
 
 - (HTMLElement *)childElementAtIndex:(NSUInteger)index
 {
 	NSUInteger counter = 0;
-	for (HTMLNode *node in self.childNodes) {
+	for (HTMLNode *node in _childNodes) {
 		if (node.nodeType == HTMLNodeElement) {
 			if (counter == index) {
 				return node.asElement;
@@ -205,7 +224,7 @@
 - (NSUInteger)indexOfChildElement:(HTMLElement *)element
 {
 	NSUInteger counter = 0;
-	for (HTMLNode *node in self.childNodes) {
+	for (HTMLNode *node in _childNodes) {
 		if (node.nodeType == HTMLNodeElement) {
 			if (node == element) {
 				return counter;
@@ -262,7 +281,9 @@
 		[node removeAllChildNodes];
 	}
 
-	[nodes makeObjectsPerformSelector:@selector(setParentNode:) withObject:self];
+	for (HTMLNode *node in nodes) {
+		[node setParentNode:self];
+	}
 
 	return node;
 }
@@ -290,7 +311,7 @@
 
 - (void)removeFromParentNode
 {
-	[self.parentNode removeChildNode:self];
+	[_parentNode removeChildNode:self];
 }
 
 - (HTMLNode *)removeChildNode:(HTMLNode *)child
@@ -298,7 +319,7 @@
 	if (child.parentNode != self) {
 		[NSException raise:HTMLKitNotFoundError
 					format:@"%@: Not Fount Error, removing non-child node %@. The object can not be found here.",
-		 NSStringFromSelector(_cmd), child];
+		 RemoveChildNode, child];
 	}
 
 	HTMLNode *oldNode = child;
@@ -322,16 +343,18 @@
 
 - (void)reparentChildNodesIntoNode:(HTMLNode *)node
 {
-	for (HTMLNode *child in self.childNodes.array) {
+	for (HTMLNode *child in _childNodes) {
 		[node appendNode:child];
 	}
-	[(NSMutableOrderedSet *)self.childNodes removeAllObjects];
+	[(NSMutableOrderedSet *)_childNodes removeAllObjects];
 }
 
 - (void)removeAllChildNodes
 {
-	[self.childNodes.array makeObjectsPerformSelector:@selector(setParentNode:) withObject:nil];
-	[(NSMutableOrderedSet *)self.childNodes removeAllObjects];
+	for (HTMLNode *child in _childNodes) {
+		[child setParentNode:nil];
+	}
+	[(NSMutableOrderedSet *)_childNodes removeAllObjects];
 }
 
 - (HTMLDocumentPosition)compareDocumentPositionWithNode:(HTMLNode *)otherNode
@@ -402,7 +425,7 @@
 		return self.nodeType != HTMLNodeDocument && self.ownerDocument == otherNode;
 	}
 
-	for (HTMLNode *parentNode = self.parentNode; parentNode; parentNode = parentNode.parentNode) {
+	for (HTMLNode *parentNode = _parentNode; parentNode; parentNode = parentNode.parentNode) {
 		if (parentNode == otherNode) {
 			return YES;
 		}
@@ -424,7 +447,7 @@
 		return;
 	}
 
-	[self.childNodes enumerateObjectsUsingBlock:^(id obj, NSUInteger idx, BOOL *stop) {
+	[_childNodes enumerateObjectsUsingBlock:^(id obj, NSUInteger idx, BOOL *stop) {
 		block(obj, idx, stop);
 	}];
 }
@@ -435,7 +458,7 @@
 		return;
 	}
 
-	[self.childNodes enumerateObjectsUsingBlock:^(id obj, NSUInteger idx, BOOL *stop) {
+	[_childNodes enumerateObjectsUsingBlock:^(id obj, NSUInteger idx, BOOL *stop) {
 		if ([obj isKindOfClass:[HTMLElement class]]) {
 			block([obj asElement], idx, stop);
 		}
@@ -558,18 +581,18 @@ NS_INLINE void CheckInvalidCombination(HTMLNode *parent, HTMLNode *node, NSStrin
 
 - (void)ensurePreInsertionValidityOfNode:(HTMLNode *)node beforeChildNode:(HTMLNode *)child
 {
-	CheckParentValid(self, NSStringFromSelector(_cmd));
+	CheckParentValid(self, ValidationNodePreInsertion);
 
-	CheckChildsParent(self, child, NSStringFromSelector(_cmd));
+	CheckChildsParent(self, child, ValidationNodePreInsertion);
 
-	CheckInsertedNodeValid(node, NSStringFromSelector(_cmd));
+	CheckInsertedNodeValid(node, ValidationNodePreInsertion);
 
-	CheckInvalidCombination(self, node, NSStringFromSelector(_cmd));
+	CheckInvalidCombination(self, node, ValidationNodePreInsertion);
 
 	void (^ hierarchyError)() = ^{
 		[NSException raise:HTMLKitHierarchyRequestError
 					format:@"%@: Hierarchy Request Error, inserting (%@) into (%@). The operation would yield an incorrect node tree.",
-		 NSStringFromSelector(_cmd), self, node];
+		 ValidationNodePreInsertion, self, node];
 	};
 
 	if (self.nodeType == HTMLNodeDocument) {
@@ -608,18 +631,18 @@ NS_INLINE void CheckInvalidCombination(HTMLNode *parent, HTMLNode *node, NSStrin
 
 - (void)ensureReplacementValidityOfChildNode:(HTMLNode *)child withNode:(HTMLNode *)node
 {
-	CheckParentValid(self, NSStringFromSelector(_cmd));
+	CheckParentValid(self, ValidationNodeReplacement);
 
-	CheckChildsParent(self, child, NSStringFromSelector(_cmd));
+	CheckChildsParent(self, child, ValidationNodeReplacement);
 
-	CheckInsertedNodeValid(node, NSStringFromSelector(_cmd));
+	CheckInsertedNodeValid(node, ValidationNodeReplacement);
 
-	CheckInvalidCombination(self, node, NSStringFromSelector(_cmd));
+	CheckInvalidCombination(self, node, ValidationNodeReplacement);
 
 	void (^ hierarchyError)() = ^{
 		[NSException raise:HTMLKitHierarchyRequestError
 					format:@"%@: Hierarchy Request Error. The operation would yield an incorrect node tree.",
-		 NSStringFromSelector(_cmd)];
+		 ValidationNodeReplacement];
 	};
 
 	void (^ checkParentHasAnotherChildOfType)(HTMLNodeType) = ^ void (HTMLNodeType type) {
@@ -675,7 +698,7 @@ NS_INLINE void CheckInvalidCombination(HTMLNode *parent, HTMLNode *node, NSStrin
 	HTMLNode *copy = [self copy];
 
 	if (deep) {
-		for (HTMLNode *child in self.childNodes) {
+		for (HTMLNode *child in _childNodes) {
 			[copy appendNode:[child cloneNodeDeep:YES]];
 		}
 	}

Sources/HTMLParser.m

@@ -1272,7 +1272,7 @@
 								  @"dd": @[@"dd", @"dt"],
 								  @"dt": @[@"dd", @"dt"]};
 
-		for (HTMLElement *node in _stackOfOpenElements.reverseObjectEnumerator.allObjects) {
+		for (HTMLElement *node in _stackOfOpenElements.reverseObjectEnumerator) {
 			if ([map[tagName] containsObject:node.tagName]) {
 				[self generateImpliedEndTagsExceptForElement:node.tagName];
 				if (![self.currentNode.tagName isEqualToString:node.tagName]) {
@@ -1529,7 +1529,7 @@
 		}
 		[self closePElement];
 	} else if ([tagName isEqualToString:@"li"]) {
-		if (![_stackOfOpenElements hasElementInListItemScopeWithTagName:@"li"]) {
+		if (![_stackOfOpenElements hasElementInListItemScopeWithTagName:tagName]) {
 			[self emitParseError:@"Unexpected <li> element in <body>"];
 			return;
 		}
@@ -1549,7 +1549,7 @@
 		}
 		[_stackOfOpenElements popElementsUntilElementPoppedWithTagName:tagName];
 	} else if ([tagName isEqualToAny:@"h1", @"h2", @"h3", @"h4", @"h5", @"h6", nil]) {
-		if (![_stackOfOpenElements hasAnyElementInScopeWithAnyOfTagNames:@[@"h1", @"h2", @"h3", @"h4", @"h5", @"h6"]]) {
+		if (![_stackOfOpenElements hasHeaderElementInScope]) {
 			[self emitParseError:@"Unexpected <%@> element in <body>", tagName];
 			return;
 		}
@@ -1569,7 +1569,7 @@
 			return;
 		}
 	} else if ([tagName isEqualToAny:@"applet", @"marquee", @"object", nil]) {
-		if (![_stackOfOpenElements hasAnyElementInScopeWithAnyOfTagNames:@[@"applet", @"marquee", @"object"]]) {
+		if (![_stackOfOpenElements hasElementInScopeWithTagName:tagName]) {
 			[self emitParseError:@"Unexpected <%@> element in <body>", tagName];
 			return;
 		}
@@ -1590,7 +1590,7 @@
 
 - (void)processAnyOtherEndTagTokenInBody:(HTMLTagToken *)token
 {
-	for (HTMLElement *node in _stackOfOpenElements.reverseObjectEnumerator.allObjects) {
+	for (HTMLElement *node in _stackOfOpenElements.reverseObjectEnumerator) {
 		if ([node.tagName isEqualToString:token.tagName]) {
 			[self generateImpliedEndTagsExceptForElement:token.tagName];
 			if (![node.tagName isEqualToString:self.currentNode.tagName]) {

Sources/HTMLStackOfOpenElements.m

@@ -14,7 +14,6 @@
 @interface HTMLStackOfOpenElements ()
 {
 	NSMutableArray *_stack;
-	NSDictionary *_specificScopeElementTypes;
 }
 @end
 
@@ -27,26 +26,6 @@
 	self = [super init];
 	if (self) {
 		_stack = [NSMutableArray new];
-		_specificScopeElementTypes = @{
-									   @"applet": @(HTMLNamespaceHTML),
-									   @"caption": @(HTMLNamespaceHTML),
-									   @"html": @(HTMLNamespaceHTML),
-									   @"table": @(HTMLNamespaceHTML),
-									   @"td": @(HTMLNamespaceHTML),
-									   @"th": @(HTMLNamespaceHTML),
-									   @"marquee": @(HTMLNamespaceHTML),
-									   @"object": @(HTMLNamespaceHTML),
-									   @"template": @(HTMLNamespaceHTML),
-									   @"mi": @(HTMLNamespaceMathML),
-									   @"mo": @(HTMLNamespaceMathML),
-									   @"mn": @(HTMLNamespaceMathML),
-									   @"ms": @(HTMLNamespaceMathML),
-									   @"mtext": @(HTMLNamespaceMathML),
-									   @"annotation-xml": @(HTMLNamespaceMathML),
-									   @"foreignObject": @(HTMLNamespaceSVG),
-									   @"desc": @(HTMLNamespaceSVG),
-									   @"title": @(HTMLNamespaceSVG)
-									   };
 	}
 	return self;
 }
@@ -195,82 +174,148 @@
 
 #pragma mark - Element Scope
 
+NS_INLINE BOOL IsSpecificScopeElement(HTMLElement *element)
+{
+	switch (element.htmlNamespace) {
+		case HTMLNamespaceHTML:
+			return [element.tagName isEqualToAny:@"applet", @"caption", @"html", @"table", @"td", @"th", @"marquee", @"object", @"template", nil];
+		case HTMLNamespaceMathML:
+			return [element.tagName isEqualToAny:@"mi", @"mo", @"mn", @"ms", @"mtext", @"annotation-xml", nil];
+		case HTMLNamespaceSVG:
+			return [element.tagName isEqualToAny:@"foreignObject", @"desc", @"title", nil];
+	}
+}
+
+NS_INLINE BOOL IsHeaderElement(HTMLElement *element)
+{
+	if (element.htmlNamespace != HTMLNamespaceHTML) {
+		return NO;
+	}
+
+	return [element.tagName isEqualToAny:@"h1", @"h2", @"h3", @"h4", @"h5", @"h6", nil];
+}
+
+NS_INLINE BOOL IsTableScopeElement(HTMLElement *element)
+{
+	if (element.htmlNamespace != HTMLNamespaceHTML) {
+		return NO;
+	}
+
+	return [element.tagName isEqualToAny:@"html", @"table", @"template", nil];
+}
+
+NS_INLINE BOOL IsListItemScopeElement(HTMLElement *element)
+{
+	if (element.htmlNamespace != HTMLNamespaceHTML) {
+		return NO;
+	}
+
+	return [element.tagName isEqualToAny:@"ol", @"ul", nil];
+}
+
+NS_INLINE BOOL IsSelectScopeElement(HTMLElement *element)
+{
+	if (element.htmlNamespace != HTMLNamespaceHTML) {
+		return NO;
+	}
+
+	return ![element.tagName isEqualToString:@"optgroup"] && ![element.tagName isEqualToString:@"option"];
+}
+
+NS_INLINE BOOL IsButtonScopeElement(HTMLElement *element)
+{
+	if (element.htmlNamespace != HTMLNamespaceHTML) {
+		return NO;
+	}
+
+	return [element.tagName isEqualToString:@"button"];
+}
+
 - (HTMLElement *)hasElementInScopeWithTagName:(NSString *)tagName;
-{
-	return [self hasAnyElementInSpecificScopeWithTagNames:@[tagName] andElementTypes:_specificScopeElementTypes];
-}
-
-- (HTMLElement *)hasAnyElementInScopeWithAnyOfTagNames:(NSArray *)tagNames
-{
-	return [self hasAnyElementInSpecificScopeWithTagNames:tagNames andElementTypes:_specificScopeElementTypes];
-}
-
-- (HTMLElement *)hasElementInListItemScopeWithTagName:(NSString *)tagName
-{
-	NSMutableDictionary *elementTypes = [NSMutableDictionary dictionaryWithDictionary:_specificScopeElementTypes];
-	[elementTypes addEntriesFromDictionary:@{@"ol": @(HTMLNamespaceHTML),
-											 @"ul": @(HTMLNamespaceHTML)}];
-
-	return [self hasElementInSpecificScopeWithTagName:tagName
-									  andElementTypes:elementTypes];
-}
-
-- (HTMLElement *)hasElementInButtonScopeWithTagName:(NSString *)tagName
-{
-	NSMutableDictionary *elementTypes = [NSMutableDictionary dictionaryWithDictionary:_specificScopeElementTypes];
-	[elementTypes addEntriesFromDictionary:@{@"button": @(HTMLNamespaceHTML)}];
-
-	return [self hasElementInSpecificScopeWithTagName:tagName
-									  andElementTypes:elementTypes];
-}
-
-- (HTMLElement *)hasElementInTableScopeWithTagName:(NSString *)tagName
-{
-	return [self hasElementInSpecificScopeWithTagName:tagName
-									  andElementTypes:@{@"html": @(HTMLNamespaceHTML),
-														@"table": @(HTMLNamespaceHTML),
-														@"template": @(HTMLNamespaceHTML)}];
-}
-
-- (HTMLElement *)hasElementInTableScopeWithAnyOfTagNames:(NSArray *)tagNames
-{
-	return [self hasAnyElementInSpecificScopeWithTagNames:tagNames
-										  andElementTypes:@{@"html": @(HTMLNamespaceHTML),
-															@"table": @(HTMLNamespaceHTML),
-															@"template": @(HTMLNamespaceHTML)}];
-}
-
-- (HTMLElement *)hasElementInSelectScopeWithTagName:(NSString *)tagName
 {
 	for (HTMLElement *node in _stack.reverseObjectEnumerator) {
-		if ([node.tagName isEqualToString:tagName]) {
+		if (node.htmlNamespace == HTMLNamespaceHTML && [tagName isEqualToString:node.tagName]) {
 			return node;
 		}
-		if (!(node.htmlNamespace == HTMLNamespaceHTML &&
-			  [node.tagName isEqualToAny:@"optgroup", @"option", nil])) {
+		if (IsSpecificScopeElement(node)) {
 			return nil;
 		}
 	}
 	return nil;
 }
 
-- (HTMLElement *)hasElementInSpecificScopeWithTagName:(NSString *)tagName
-									  andElementTypes:(NSDictionary *)elementTypes
-{
-	return [self hasAnyElementInSpecificScopeWithTagNames:@[tagName] andElementTypes:elementTypes];
-}
-
-- (HTMLElement *)hasAnyElementInSpecificScopeWithTagNames:(NSArray *)tagNames
-										  andElementTypes:(NSDictionary *)elementTypes
+- (HTMLElement *)hasHeaderElementInScope
 {
 	for (HTMLElement *node in _stack.reverseObjectEnumerator) {
-		if ([tagNames containsObject:node.tagName]) {
-			NSNumber *namespace = elementTypes[node.tagName] ?: @(HTMLNamespaceHTML);
-			if ([namespace isEqual:@(node.htmlNamespace)]) {
-				return node;
-			}
+		if (IsHeaderElement(node)) {
+			return node;
 		}
-		if ([elementTypes[node.tagName] isEqual:@(node.htmlNamespace)]) {
+		if (IsSpecificScopeElement(node)) {
+			return nil;
+		}
+	}
+	return nil;
+}
+
+- (HTMLElement *)hasElementInTableScopeWithTagName:(NSString *)tagName
+{
+	for (HTMLElement *node in _stack.reverseObjectEnumerator) {
+		if (node.htmlNamespace == HTMLNamespaceHTML && [tagName isEqualToString:node.tagName]) {
+			return node;
+		}
+		if (IsTableScopeElement(node)) {
+			return nil;
+		}
+	}
+	return nil;
+}
+
+- (HTMLElement *)hasElementInTableScopeWithAnyOfTagNames:(NSArray *)tagNames
+{
+	for (HTMLElement *node in _stack.reverseObjectEnumerator) {
+		if (node.htmlNamespace == HTMLNamespaceHTML && [tagNames containsObject:node.tagName]) {
+			return node;
+		}
+		if (IsTableScopeElement(node)) {
+			return nil;
+		}
+	}
+	return nil;
+}
+
+- (HTMLElement *)hasElementInListItemScopeWithTagName:(NSString *)tagName
+{
+	for (HTMLElement *node in _stack.reverseObjectEnumerator) {
+		if (node.htmlNamespace == HTMLNamespaceHTML && [tagName isEqualToString:node.tagName]) {
+			return node;
+		}
+		if (IsSpecificScopeElement(node) || IsListItemScopeElement(node)) {
+			return nil;
+		}
+	}
+	return nil;
+}
+
+- (HTMLElement *)hasElementInButtonScopeWithTagName:(NSString *)tagName
+{
+	for (HTMLElement *node in _stack.reverseObjectEnumerator) {
+		if (node.htmlNamespace == HTMLNamespaceHTML && [tagName isEqualToString:node.tagName]) {
+			return node;
+		}
+		if (IsSpecificScopeElement(node) || IsButtonScopeElement(node)) {
+			return nil;
+		}
+	}
+	return nil;
+}
+
+- (HTMLElement *)hasElementInSelectScopeWithTagName:(NSString *)tagName
+{
+	for (HTMLElement *node in _stack.reverseObjectEnumerator) {
+		if (node.htmlNamespace == HTMLNamespaceHTML && [tagName isEqualToString:node.tagName]) {
+			return node;
+		}
+		if (IsSelectScopeElement(node)) {
 			return nil;
 		}
 	}

Sources/HTMLTokenizer.m

@@ -77,14 +77,16 @@
 
 - (id)nextObject
 {
-	while (_eof == NO && _tokens.count == 0) {
-		[self read];
+	@autoreleasepool {
+		while (_eof == NO && _tokens.count == 0) {
+			[self read];
+		}
+		HTMLToken *nextToken = [_tokens firstObject];
+		if (_tokens.count > 0) {
+			[_tokens removeObjectAtIndex:0];
+		}
+		return nextToken;
 	}
-	HTMLToken *nextToken = [_tokens firstObject];
-	if (_tokens.count > 0) {
-		[_tokens removeObjectAtIndex:0];
-	}
-	return nextToken;
 }
 
 - (void)read

Sources/include/HTMLElement.h

@@ -75,7 +75,7 @@ NS_ASSUME_NONNULL_BEGIN
  @param attributes The attributes.
  @return A new HTML element.
  */
-- (instancetype)initWithTagName:(NSString *)tagName attributes:(NSDictionary<NSString *, NSString *> *)attributes;
+- (instancetype)initWithTagName:(NSString *)tagName attributes:(nullable NSDictionary<NSString *, NSString *> *)attributes;
 
 /**
  Initializes a new HTML element with the given tag name, namespace, and attributes.
@@ -85,7 +85,7 @@ NS_ASSUME_NONNULL_BEGIN
  @param attributes The attributes.
  @return A new HTML element.
  */
-- (instancetype)initWithTagName:(NSString *)tagName namespace:(HTMLNamespace)htmlNamespace attributes:(NSDictionary<NSString *, NSString *> *)attributes;
+- (instancetype)initWithTagName:(NSString *)tagName namespace:(HTMLNamespace)htmlNamespace attributes:(nullable NSDictionary<NSString *, NSString *> *)attributes;
 
 /**
  Checks whether this element has an attribute with the given name.

Sources/include/HTMLStackOfOpenElements.h

@@ -163,11 +163,11 @@
  https://html.spec.whatwg.org/multipage/syntax.html#has-an-element-in-the-specific-scope
  */
 - (HTMLElement *)hasElementInScopeWithTagName:(NSString *)tagName;
-- (HTMLElement *)hasAnyElementInScopeWithAnyOfTagNames:(NSArray *)tagNames;
-- (HTMLElement *)hasElementInListItemScopeWithTagName:(NSString *)tagName;
-- (HTMLElement *)hasElementInButtonScopeWithTagName:(NSString *)tagName;
+- (HTMLElement *)hasHeaderElementInScope;
 - (HTMLElement *)hasElementInTableScopeWithTagName:(NSString *)tagName;
 - (HTMLElement *)hasElementInTableScopeWithAnyOfTagNames:(NSArray *)tagNames;
+- (HTMLElement *)hasElementInListItemScopeWithTagName:(NSString *)tagName;
+- (HTMLElement *)hasElementInButtonScopeWithTagName:(NSString *)tagName;
 - (HTMLElement *)hasElementInSelectScopeWithTagName:(NSString *)tagName;
 
 /**