[xlinq] add test from bug #14856.

1 files changed, 33 insertions, 0 deletions

diff --git a/mcs/class/System.Xml.Linq/Test/System.Xml.Linq/XElementTest.cs b/mcs/class/System.Xml.Linq/Test/System.Xml.Linq/XElementTest.cs
index 69c3f23f164..b4fd35cac19 100644
--- a/mcs/class/System.Xml.Linq/Test/System.Xml.Linq/XElementTest.cs
+++ b/mcs/class/System.Xml.Linq/Test/System.Xml.Linq/XElementTest.cs
@@ -29,6 +29,7 @@ using System.Collections.Generic;
 using System.Globalization;
 using System.IO;
 using System.Linq;
+using System.Text;
 using System.Threading;
 using System.Xml;
 using System.Xml.Linq;
@@ -2107,5 +2108,37 @@ namespace MonoTests.System.Xml.Linq
 			var el = new XElement ("test", (object)content);
 			Assert.AreEqual ("<test>content1content2</test>", el.ToString ());
 		}
+
+		[Test] // bug #14856
+		public void PossibleDuplicateNamespaces ()
+		{
+            string testXML =
+                "<?xml version=\"1.0\" encoding=\"utf-8\"?>" +
+                "<TestElement xmlns=\"http://www.test.com/TestNamespace\" />";
+
+            using (var stream = new MemoryStream (Encoding.UTF8.GetBytes (testXML)))
+            {
+                var root = XElement.Load (stream);
+                using (var savedStream = new MemoryStream ())
+                {
+                    var options = SaveOptions.None;
+
+                    // Comment out this line to make it not crash.
+                    options |= SaveOptions.OmitDuplicateNamespaces;
+
+                    root.Save (savedStream, options);
+                    savedStream.Flush ();
+                    savedStream.Position = 0;
+
+                    var settings = new XmlReaderSettings { IgnoreComments = true, IgnoreWhitespace = true };
+                    using (var xmlReader = XmlReader.Create (savedStream, settings))
+                    {
+                        while (xmlReader.Read ())
+                        {
+                        }
+                    }
+                }
+            }
+		}
 	}
 }