1 files changed, 85 insertions, 0 deletions
diff --git a/Xamarin.Forms.Xaml/PruneIgnoredNodesVisitor.cs b/Xamarin.Forms.Xaml/PruneIgnoredNodesVisitor.cs
new file mode 100644
index 00000000..95ddb20f
--- /dev/null
+++ b/Xamarin.Forms.Xaml/PruneIgnoredNodesVisitor.cs
@@ -0,0 +1,85 @@
+using System.Collections.Generic;
+using System.Linq;
+
+namespace Xamarin.Forms.Xaml
+{
+	class PruneIgnoredNodesVisitor : IXamlNodeVisitor
+	{
+		public bool StopOnDataTemplate {
+			get { return false; }
+		}
+
+		public bool StopOnResourceDictionary {
+			get { return false; }
+		}
+
+		public bool VisitChildrenFirst {
+			get { return false; }
+		}
+
+		public void Visit(ElementNode node, INode parentNode)
+		{
+			foreach (var propertyKvp in node.Properties)
+			{
+				var propertyName = propertyKvp.Key;
+				var propertyValue = (propertyKvp.Value as ValueNode)?.Value as string;
+				if (propertyValue == null)
+					continue;
+				if (propertyName.NamespaceURI != "http://schemas.openxmlformats.org/markup-compatibility/2006" ||
+					propertyName.LocalName != "Ignorable")
+					continue;
+				(parentNode.IgnorablePrefixes ?? (parentNode.IgnorablePrefixes = new List<string>())).AddRange(propertyValue.Split(','));
+			}
+
+			foreach (var propertyKvp in node.Properties.ToList())
+			{
+				// skip d:foo="bar"
+				var prefix = node.NamespaceResolver.LookupPrefix(propertyKvp.Key.NamespaceURI);
+				if (node.SkipPrefix(prefix))
+					node.Properties.Remove(propertyKvp.Key);
+				var propNs = (propertyKvp.Value as IElementNode)?.NamespaceURI ?? "";
+				var propPrefix = node.NamespaceResolver.LookupPrefix(propNs);
+				if (node.SkipPrefix(propPrefix))
+					node.Properties.Remove(propertyKvp.Key);
+			}
+
+			foreach (var prop in node.CollectionItems.ToList())
+			{
+				var propNs = (prop as IElementNode)?.NamespaceURI ?? "";
+				var propPrefix = node.NamespaceResolver.LookupPrefix(propNs);
+				if (node.SkipPrefix(propPrefix))
+					node.CollectionItems.Remove(prop);
+			}
+
+			if (node.SkipPrefix(node.NamespaceResolver.LookupPrefix(node.NamespaceURI)))
+			{
+				node.Properties.Clear();
+				node.CollectionItems.Clear();
+			}
+		}
+
+		public void Visit(RootNode node, INode parentNode)
+		{
+			Visit((ElementNode)node, node);
+		}
+
+		public void Visit(MarkupNode node, INode parentNode)
+		{
+		}
+
+		public void Visit(ListNode node, INode parentNode)
+		{
+			foreach (var prop in node.CollectionItems.ToList())
+			{
+				var propNs = (prop as IElementNode)?.NamespaceURI ?? "";
+				var propPrefix = node.NamespaceResolver.LookupPrefix(propNs);
+				if (node.SkipPrefix(propPrefix))
+					node.CollectionItems.Remove(prop);
+			}
+		}
+
+		public void Visit(ValueNode node, INode parentNode)
+		{
+		}
+	}
+}
+\ No newline at end of file