Fix bug #12035 - xsi:nil='true' was ignored in some scenario.

"some scenario" I mean:

- There is a sequence with more than one elements in xsd,
- The second element is nillable and its type has content elements, and
- The corresponding XML element specifies xsi:nil='true'

Then it resulted in a validation error as if it were missing the required
content.

3 files changed, 49 insertions, 4 deletions

diff --git a/mcs/class/System.XML/Mono.Xml.Schema/XsdValidatingReader.cs b/mcs/class/System.XML/Mono.Xml.Schema/XsdValidatingReader.cs
index 7f19ce58d3d..f6b56c6b3c6 100644
--- a/mcs/class/System.XML/Mono.Xml.Schema/XsdValidatingReader.cs
+++ b/mcs/class/System.XML/Mono.Xml.Schema/XsdValidatingReader.cs
@@ -473,7 +473,7 @@ namespace Mono.Xml.Schema
 
 		private void ValidateEndElementParticle ()
 		{
-			if (Context.State != null) {
+			if (xsiNilDepth < 0 && Context.State != null) {
 				if (!Context.EvaluateEndElement ()) {
 					HandleError ("Invalid end element: " + reader.Name);
 				}
diff --git a/mcs/class/System.XML/System.Xml.Schema/XmlSchemaValidator.cs b/mcs/class/System.XML/System.Xml.Schema/XmlSchemaValidator.cs
index 92274b2e157..286963d3056 100644
--- a/mcs/class/System.XML/System.Xml.Schema/XmlSchemaValidator.cs
+++ b/mcs/class/System.XML/System.Xml.Schema/XmlSchemaValidator.cs
@@ -539,10 +539,10 @@ namespace System.Xml.Schema
 
 				if (skipValidationDepth < 0 || depth <= skipValidationDepth)
 					AssessCloseStartElementSchemaValidity (schemaInfo);
-				depth++;
 			} finally {
 				current_info = null;
 				occuredAtts.Clear ();
+				depth++;
 			}
 		}
 
@@ -976,7 +976,7 @@ namespace System.Xml.Schema
 
 		private void ValidateEndElementParticle ()
 		{
-			if (Context.State != null) {
+			if (xsiNilDepth < 0 && Context.State != null) {
 				if (!Context.EvaluateEndElement ()) {
 					HandleError ("Invalid end element. There are still required content items.");
 				}
@@ -1588,7 +1588,8 @@ namespace System.Xml.Schema
 			if (value == "true") {
 				if (element.ValidatedFixedValue != null)
 					HandleError ("Schema instance nil was specified, where the element declaration for " + element.QualifiedName + "has fixed value constraints.");
-				xsiNilDepth = depth;
+				if (xsiNilDepth < 0)
+					xsiNilDepth = depth;
 				if (info != null)
 					info.IsNil = true;
 			}
diff --git a/mcs/class/System.XML/Test/System.Xml.Schema/XmlSchemaValidatorTests.cs b/mcs/class/System.XML/Test/System.Xml.Schema/XmlSchemaValidatorTests.cs
index bf258f6cc17..6f7ec34a5dd 100644
--- a/mcs/class/System.XML/Test/System.Xml.Schema/XmlSchemaValidatorTests.cs
+++ b/mcs/class/System.XML/Test/System.Xml.Schema/XmlSchemaValidatorTests.cs
@@ -397,6 +397,50 @@ namespace MonoTests.System.Xml
 				i++;
 			Assert.AreEqual (2, i, "#2");
 		}
+		
+		[Test]
+		public void Bug12035 ()
+		{
+			string xml = @"<UserSettings
+  xmlns:xsi='http://www.w3.org/2001/XMLSchema-instance'
+  xmlns:xsd='http://www.w3.org/2001/XMLSchema'
+  xmlns='http://schema/test'><Enabled>false</Enabled><Time xsi:nil='true' /></UserSettings>";
+			string xsd = @"<?xml version='1.0' encoding='utf-8'?>
+<xs:schema
+  targetNamespace='http://schema/test'
+  xmlns='http://schema/test'
+  xmlns:xs='http://www.w3.org/2001/XMLSchema'
+  elementFormDefault='qualified'>
+  <xs:element name='UserSettings'>
+    <xs:complexType>
+      <xs:sequence>
+        <xs:element name='Enabled' type='xs:boolean' />
+        <xs:element name='Time' type='CoarseTime' nillable='true' />
+      </xs:sequence>
+    </xs:complexType>
+  </xs:element>
+
+  <xs:complexType name='CoarseTime'>
+    <xs:sequence>
+      <xs:element name='Hours' type='xs:int' />
+    </xs:sequence>
+  </xs:complexType>
+</xs:schema>";
+			var schema = XmlSchema.Read (new StringReader (xsd), null);
+			var schemaSet = new XmlSchemaSet ();
+			schemaSet.Add (schema);
+			var xmlReaderSettings = new XmlReaderSettings { ValidationType = ValidationType.Schema };
+			xmlReaderSettings.ValidationFlags |= XmlSchemaValidationFlags.ReportValidationWarnings;
+			xmlReaderSettings.Schemas.Add (schemaSet);
+			
+			using (var configStream = new StringReader (xml)) {
+				using (var validatingReader = XmlReader.Create (configStream, xmlReaderSettings)) {
+					// Read the XML, throwing an exception if a validation error occurs
+					while (validatingReader.Read()) {
+					}
+				}
+			}
+		}
 	}
 }