Write custom styles as styles instead of as properties

- fixes styles written as invalid properties
- fixes part of #129 (issues 2 an 3), added test images

Source/SvgDefinitionDefaults.cs

@@ -33,8 +33,6 @@ namespace Svg
                 { "clip", "auto" },
                 { "clip-rule", "nonzero" },
                 { "clipPathUnits", "userSpaceOnUse" },
-                { "x", "0" },
-                { "y", "0" },
                 { "transform", "" },
 
                 // line

Source/SvgElement.cs

@@ -65,11 +65,18 @@ namespace Svg
         }
         public void FlushStyles()
         {
-            foreach (var s in _styles)
+            if (_styles.Any())
             {
-                SvgElementFactory.SetPropertyValue(this, s.Key, s.Value.Last().Value, this.OwnerDocument);
+                var styles = new Dictionary<string, SortedDictionary<int, string>>();
+                foreach (var s in _styles)
+                {
+                    if (!SvgElementFactory.SetPropertyValue(this, s.Key, s.Value.Last().Value, this.OwnerDocument, isStyle: true))
+                    {
+                        styles.Add(s.Key, s.Value);
+                    }
+                }
+                _styles = styles;
             }
-            _styles = null;
         }
 
 
@@ -77,7 +84,7 @@ namespace Svg
         {
             SortedDictionary<int, string> rules;
             return (this.Attributes.ContainsKey(name) || this.CustomAttributes.ContainsKey(name) ||
-                (_styles != null && _styles.TryGetValue(name, out rules)) && (rules.ContainsKey(StyleSpecificity_InlineStyle) || rules.ContainsKey(StyleSpecificity_PresAttribute)));
+                (_styles.TryGetValue(name, out rules)) && (rules.ContainsKey(StyleSpecificity_InlineStyle) || rules.ContainsKey(StyleSpecificity_PresAttribute)));
         }
         public bool TryGetAttribute(string name, out string value)
         {
@@ -89,7 +96,7 @@ namespace Svg
             }
             if (this.CustomAttributes.TryGetValue(name, out value)) return true;
             SortedDictionary<int, string> rules;
-            if (_styles != null && _styles.TryGetValue(name, out rules))
+            if (_styles.TryGetValue(name, out rules))
             {
                 // Get staged styles that are 
                 if (rules.TryGetValue(StyleSpecificity_InlineStyle, out value)) return true;
@@ -564,7 +571,7 @@ namespace Svg
         }
         protected virtual void WriteAttributes(XmlTextWriter writer)
         {
-            var styles = new Dictionary<string, string>();
+            var styles = _styles.ToDictionary(_styles => _styles.Key, _styles => _styles.Value.Last().Value);
             bool writeStyle;
             bool forceWrite;
 

Source/SvgElementFactory.cs

@@ -230,7 +230,7 @@ namespace Svg
         private static Dictionary<Type, Dictionary<string, PropertyDescriptorCollection>> _propertyDescriptors = new Dictionary<Type, Dictionary<string, PropertyDescriptorCollection>>();
         private static object syncLock = new object();
 
-        internal static void SetPropertyValue(SvgElement element, string attributeName, string attributeValue, SvgDocument document)
+        internal static bool SetPropertyValue(SvgElement element, string attributeName, string attributeValue, SvgDocument document, bool isStyle=false)
         {
             var elementType = element.GetType();
 
@@ -298,10 +298,16 @@ namespace Svg
                 }
                 else
                 {
+                    if (isStyle)
+                    {
+                        // custom styles shall remain as style
+                        return false;
+                    }
                     //attribute is not a svg attribute, store it in custom attributes
                     element.CustomAttributes[attributeName] = attributeValue;
                 }
             }
+            return true;
         }
 
         /// <summary>

Tests/Svg.UnitTests/PassingTests.csv

@@ -176,6 +176,7 @@ __issue-084-01
 __issue-109-01
 __issue-116-01
 __issue-123-01
+__issue-129-01
 __issue-143-01
 __issue-191-01
 __issue-202-01