From 6217bc4299613fe6bfe3645047b5bc01ec480cce Mon Sep 17 00:00:00 2001
From: iska <iska.gp@gmail.com>
Date: Sun, 1 Mar 2015 03:27:24 +0100
Subject: [PATCH] Add Character Token methods for splitting leading whitespace

Since all successive characters are accumulated into the character token in the
tokenization stage, leading whitespace must be explicitly ignored during the tree
construction, hence these methods.
---
 HTMLKit/HTMLCharacterToken.h |  2 ++
 HTMLKit/HTMLCharacterToken.m | 33 +++++++++++++++++++++++++++++++++
 2 files changed, 35 insertions(+)

diff --git a/HTMLKit/HTMLCharacterToken.h b/HTMLKit/HTMLCharacterToken.h
index ce61a9f..56ad1ad 100644
--- a/HTMLKit/HTMLCharacterToken.h
+++ b/HTMLKit/HTMLCharacterToken.h
@@ -18,5 +18,7 @@
 - (void)appendString:(NSString *)string;
 
 - (BOOL)isWhitespaceToken;
+- (HTMLCharacterToken *)tokenByRetainingLeadingWhitespace;
+- (HTMLCharacterToken *)tokenByTrimmingLeadingWhitespace;
 
 @end
diff --git a/HTMLKit/HTMLCharacterToken.m b/HTMLKit/HTMLCharacterToken.m
index 035c627..9255bd1 100644
--- a/HTMLKit/HTMLCharacterToken.m
+++ b/HTMLKit/HTMLCharacterToken.m
@@ -8,6 +8,19 @@
 
 #import "HTMLCharacterToken.h"
 
+NS_INLINE BOOL isHtmlWhitespace(char c)
+{
+	return c == ' ' || c == '\t' || c == '\n' || c == '\f' || c == '\r';
+}
+
+NS_INLINE size_t LeadingWhitespaceLength(NSString *string)
+{
+	const char *str = string.UTF8String;
+	size_t idx = 0;
+	while (isHtmlWhitespace(*str)) { str++; idx++; }
+	return idx;
+}
+
 @interface HTMLCharacterToken ()
 {
 	NSMutableString *_characters;
@@ -40,6 +53,26 @@
 	return [_characters rangeOfCharacterFromSet:set].location == NSNotFound;
 }
 
+- (HTMLCharacterToken *)tokenByRetainingLeadingWhitespace
+{
+	size_t index = LeadingWhitespaceLength(_characters);
+	if (index > 0) {
+		NSString *leading = [_characters substringToIndex:index];
+		return [[HTMLCharacterToken alloc] initWithString:leading];
+	}
+	return nil;
+}
+
+- (HTMLCharacterToken *)tokenByTrimmingLeadingWhitespace
+{
+	size_t index = LeadingWhitespaceLength(_characters);
+	if (index < _characters.length) {
+		NSString *remaining = [_characters substringFromIndex:index];
+		return [[HTMLCharacterToken alloc] initWithString:remaining];
+	}
+	return nil;
+}
+
 #pragma mark - NSObject
 
 - (BOOL)isEqual:(id)other