Fixed a error that occurred when removing quotes from attribute with an empty value

Author: Taritsyn

src/WebMarkupMin.Core/GenericHtmlMinifier.cs

@@ -1565,19 +1565,20 @@ private static bool CanRemoveAttributeQuotes(HtmlAttribute attribute,
 			string attributeValue = attribute.Value;
 			bool result = false;
 
-			if (attributeQuotesRemovalMode != HtmlAttributeQuotesRemovalMode.KeepQuotes)
+			switch (attributeQuotesRemovalMode)
 			{
-				if (!attributeValue.EndsWith("/"))
-				{
-					if (attributeQuotesRemovalMode == HtmlAttributeQuotesRemovalMode.Html4)
-					{
-						result = HtmlAttributeValueHelpers.IsHtml4AttributeValueNotRequireQuotes(attributeValue);
-					}
-					else if (attributeQuotesRemovalMode == HtmlAttributeQuotesRemovalMode.Html5)
-					{
-						result = HtmlAttributeValueHelpers.IsHtml5AttributeValueNotRequireQuotes(attributeValue);
-					}
-				}
+				case HtmlAttributeQuotesRemovalMode.KeepQuotes:
+					result = false;
+					break;
+				case HtmlAttributeQuotesRemovalMode.Html4:
+					result = HtmlAttributeValueHelpers.IsNotRequireQuotesInHtml4(attributeValue);
+					break;
+				case HtmlAttributeQuotesRemovalMode.Html5:
+					result = HtmlAttributeValueHelpers.IsNotRequireQuotesInHtml5(attributeValue);
+					break;
+				default:
+					result = false;
+					break;
 			}
 
 			return result;

src/WebMarkupMin.Core/Helpers/HtmlAttributeValueHelpers.cs

@@ -19,10 +19,16 @@ internal static class HtmlAttributeValueHelpers
 		/// </summary>
 		private static readonly char[] _encodingCharsWithSingleQuote = { '\'', '&', '<' };
 
-		public static bool IsHtml4AttributeValueNotRequireQuotes(string value)
+
+		public static bool IsNotRequireQuotesInHtml4(string value)
 		{
-			bool result = true;
 			int charCount = value.Length;
+			if (charCount == 0 || value[charCount - 1] == '/')
+			{
+				return false;
+			}
+
+			bool result = true;
 
 			for (int charIndex = 0; charIndex < charCount; charIndex++)
 			{
@@ -46,10 +52,15 @@ public static bool IsHtml4AttributeValueNotRequireQuotes(string value)
 			return result;
 		}
 
-		public static bool IsHtml5AttributeValueNotRequireQuotes(string value)
+		public static bool IsNotRequireQuotesInHtml5(string value)
 		{
-			bool result = true;
 			int charCount = value.Length;
+			if (charCount == 0 || value[charCount - 1] == '/')
+			{
+				return false;
+			}
+
+			bool result = true;
 
 			for (int charIndex = 0; charIndex < charCount; charIndex++)
 			{

src/WebMarkupMin.Core/HtmlAttributeExpression.cs

@@ -256,8 +256,7 @@ public bool IsMatch(string tagNameInLowercase, string attributeNameInLowercase,
 		/// <returns>Quotation mark</returns>
 		private static string GetQuoteForAttributeValue(string attributeValue)
 		{
-			if (attributeValue.Length > 0 && !attributeValue.EndsWith("/")
-				&& HtmlAttributeValueHelpers.IsHtml5AttributeValueNotRequireQuotes(attributeValue))
+			if (HtmlAttributeValueHelpers.IsNotRequireQuotesInHtml5(attributeValue))
 			{
 				return string.Empty;
 			}

src/WebMarkupMin.Core/WebMarkupMin.Core.csproj

@@ -18,9 +18,10 @@ Minification of markup produces by removing extra whitespaces, comments and redu
 
 Also supports minification of views of popular JavaScript template engines: KnockoutJS, Kendo UI MVVM and AngularJS 1.X.</Description>
 		<PackageTags>WebMarkupMin;Markup;HTML;XHTML;XML;Minification;Minifier;Minify;Performance;Optimization;Compression</PackageTags>
-		<PackageReleaseNotes>1. `RemoveEndingSemicolon` method of `Utils` class was renamed to the `RemoveEndingSemicolons` (implementation has also been changed);
-2. Mads Kristensen's CSS minifier has been refactored;
-3. Improved performance of the Douglas Crockford's JS minifier.</PackageReleaseNotes>
+		<PackageReleaseNotes>1. Fixed a error that occurred when removing quotes from attribute with an empty value;
+2. `RemoveEndingSemicolon` method of `Utils` class was renamed to the `RemoveEndingSemicolons` (implementation has also been changed);
+3. Mads Kristensen's CSS minifier has been refactored;
+4. Improved performance of adapter for the Douglas Crockford's JS minifier.</PackageReleaseNotes>
 	</PropertyGroup>
 
 	<Import Project="../../build/common.props" />

src/WebMarkupMin.Core/readme.txt

@@ -46,10 +46,12 @@
    =============
    RELEASE NOTES
    =============
-   1. `RemoveEndingSemicolon` method of `Utils` class was renamed to the
+   1. Fixed a error that occurred when removing quotes from attribute with an empty
+      value;
+   2. `RemoveEndingSemicolon` method of `Utils` class was renamed to the
       `RemoveEndingSemicolons` (implementation has also been changed);
-   2. Mads Kristensen's CSS minifier has been refactored;
-   3. Improved performance of the Douglas Crockford's JS minifier.
+   3. Mads Kristensen's CSS minifier has been refactored;
+   4. Improved performance of adapter for the Douglas Crockford's JS minifier.
 
    =============
    DOCUMENTATION

test/WebMarkupMin.Core.Test/Html/MinificationTests.cs

@@ -5274,6 +5274,8 @@ public void RemovingAttributeQuotesIsCorrect()
 				;
 			const string targetOutput18C = targetOutput18B;
 
+			const string input19 = "<input data-options=\"\">";
+
 			// Act
 			string output1A = keepingAttributeQuotesMinifier.Minify(input1).MinifiedContent;
 			string output1B = html4RemovingAttributeQuotesMinifier.Minify(input1).MinifiedContent;
@@ -5347,6 +5349,10 @@ public void RemovingAttributeQuotesIsCorrect()
 			string output18B = html4RemovingAttributeQuotesMinifier.Minify(input18).MinifiedContent;
 			string output18C = html5RemovingAttributeQuotesMinifier.Minify(input18).MinifiedContent;
 
+			string output19A = keepingAttributeQuotesMinifier.Minify(input19).MinifiedContent;
+			string output19B = html4RemovingAttributeQuotesMinifier.Minify(input19).MinifiedContent;
+			string output19C = html5RemovingAttributeQuotesMinifier.Minify(input19).MinifiedContent;
+
 			// Assert
 			Assert.Equal(targetOutput1A, output1A);
 			Assert.Equal(targetOutput1B, output1B);
@@ -5419,6 +5425,10 @@ public void RemovingAttributeQuotesIsCorrect()
 			Assert.Equal(targetOutput18A, output18A);
 			Assert.Equal(targetOutput18B, output18B);
 			Assert.Equal(targetOutput18C, output18C);
+
+			Assert.Equal(input19, output19A);
+			Assert.Equal(input19, output19B);
+			Assert.Equal(input19, output19C);
 		}
 
 		#endregion