implemented UsingStatement and added unit tests

git-svn-id: svn://svn.sharpdevelop.net/sharpdevelop/branches/vbnet@5980 1ccf3a8d-04fe-1044-b7c0-cef0b8235c61

src/Libraries/NRefactory/Project/Src/Parser/VBNet/Experimental/ExpressionFinder.atg

@@ -526,6 +526,7 @@ Statement =
 	| BranchStatement
 	| ReDimStatement
 	| EraseStatement
+	| UsingStatement
 	| InvocationStatement
 .
 
@@ -664,6 +665,12 @@ EraseStatement =
 	"Erase" Expression { "," Expression }
 .
 
+UsingStatement =
+	"Using" Expression
+	StatementTerminatorAndBlock
+	"End" "Using"
+.
+
 InvocationStatement =
 	[ "Call" ] Expression
 .

src/Libraries/NRefactory/Project/Src/Parser/VBNet/Experimental/Test/XmlModeLexerTests.cs

@@ -732,6 +732,23 @@ ReDim Preserve <Test />";
 			
 			CheckFoot(lexer);
 		}
+		
+		[Test]
+		public void UsingStatement()
+		{
+			string statement = @"Using <Test />
+End Using";
+			
+			ILexer lexer = GenerateLexer(new StringReader(TestStatement(statement)));
+			
+			CheckHead(lexer);
+			
+			CheckTokens(lexer, Tokens.Using, Tokens.XmlOpenTag, Tokens.Identifier, Tokens.XmlCloseTagEmptyElement, Tokens.EOL,
+			            Tokens.End, Tokens.Using
+			           );
+			
+			CheckFoot(lexer);
+		}
 		#endregion
 		
 		#region Helpers