fixed similar bug as in rev. 6405, but with Using statements, added unit tests

git-svn-id: svn://svn.sharpdevelop.net/sharpdevelop/trunk@6408 1ccf3a8d-04fe-1044-b7c0-cef0b8235c61

src/Libraries/NRefactory/Project/Src/Lexer/VBNet/ExpressionFinder.atg

@@ -1228,10 +1228,10 @@ UsingVariable =
 						  "Explicit", "Equals", "Distinct", "Descending", "Compare", "By",
 						  "Binary", "Auto", "Assembly", "Ascending", "Ansi", "Aggregate", ident)
 		(
-			(. PushContext(Context.Identifier, la, t); .) (.OnEachPossiblePath: SetIdentifierExpected(la); .) Identifier (. PopContext(); .) 
+			(. PushContext(Context.Identifier, la, t); .) (.OnEachPossiblePath: SetIdentifierExpected(la); .) Identifier
 			// HACK: needs to be optional because Expression can start with Identifier too
-			[
-				"As" [ EXPECTEDCONFLICT("Where", "UShort", "Until", "Unicode", "ULong", "UInteger", "Text", "Take",
+			[ (. PopContext(); isAlreadyInExpr = true; .)
+				( "As" [ EXPECTEDCONFLICT("Where", "UShort", "Until", "Unicode", "ULong", "UInteger", "Text", "Take",
 		                 "String", "Skip", "Single", "Short", "SByte", "Preserve", "Out", "Order",
 		                 "Off", "Object", "Long", "Key", "Join", "Into", "Integer", "Infer", "Group",
 		                 "From", "Explicit", "Equals", "Double", "Distinct", "Descending", "Decimal",
@@ -1247,10 +1247,12 @@ UsingVariable =
 				.)
 				ANY /* never reached due to goto above: */
 				/* this ANY is just so that Coco knows this branch isn't empty */
+				)
 			]
 		)
 	]
 	Expression
+	(. if (!isAlreadyInExpr) PopContext(); isAlreadyInExpr = false; .)
 .
 
 UsingStatement =

src/Main/Base/Test/VBExpressionFinderTests.cs

@@ -590,6 +590,42 @@ End Module", "data", ExpressionContext.Default);
 End Module", "DataGridViewCellStyle", ExpressionContext.Type);
 		}
 		
+		[Test]
+		public void Using1()
+		{
+			FindFull(@"Module Test
+	Sub Main()
+		Using |x As FileReader = New FileReader()
+		
+		End Using
+	End Sub
+End Module", "x", ExpressionContext.Default);
+			
+			FindFull(@"Module Test
+	Sub Main()
+		Using x As FileR|eader = New FileReader()
+		
+		End Using
+	End Sub
+End Module", "FileReader", ExpressionContext.Type);
+			
+			FindFull(@"Module Test
+	Sub Main()
+		Using x As New FileR|eader()
+		
+		End Using
+	End Sub
+End Module", "FileReader()", ExpressionContext.ObjectCreation);
+			
+			FindFull(@"Module Test
+	Sub Main()
+		Using FileRea|der()
+		
+		End Using
+	End Sub
+End Module", "FileReader()", ExpressionContext.Default);
+		}
+		
 		#region Old Tests
 		void OldTest(string expr, int offset)
 		{