fix Cannot load designer when using 'select case' - http://community.sharpdevelop.net/forums/p/15838/41446.aspx#41446

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

@@ -1137,10 +1137,19 @@ MultilineIfRemainder =
 SelectStatement =
 	"Select" [ "Case" ] Expression StatementTerminator
 	{
-		"Case" (
+		// HACK: '<' is recognized as XML literal, if occurring at the start of an expression
+		// in the CaseClause however it can only be a less-than-sign and vbc does not allow XML literals.
+		// we use a simple xmlAllowed flag:
+		// the flag is only set to false immetiately before the expression is parsed and set to true once '<'
+		// is recognized as less-than-sign to allow normal behavior of the lexer in later expressions.
+		"Case" (. xmlAllowed = false; .) (
 			"Else" |
-			( [ "Is" ] ComparisonOperator SimpleExpressionWithSuffix | Expression )
-				{ "," ( [ "Is" ] ComparisonOperator SimpleExpressionWithSuffix | Expression ) }
+			( (. xmlAllowed = true; .) [ "Is" ] ComparisonOperator SimpleExpressionWithSuffix
+			  | (. xmlAllowed = true; .) Expression )
+				{ "," (. xmlAllowed = false; .)
+				  ( (. xmlAllowed = true; .) [ "Is" ] ComparisonOperator SimpleExpressionWithSuffix
+				  | (. xmlAllowed = true; .) Expression )
+				}
 		)
 		StatementTerminatorAndBlock
 	}

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

@@ -121,6 +121,10 @@ namespace ICSharpCode.NRefactory.Parser.VB
 			set { readXmlIdentifier = value; }
 		}
 		
+		public bool XmlAllowed {
+			get { return xmlAllowed; }
+		}
+		
 		public bool NextTokenIsStartOfImportsOrAccessExpression {
 			get { return nextTokenIsStartOfImportsOrAccessExpression; }
 		}

src/Libraries/NRefactory/Project/Src/Lexer/VBNet/Lexer.cs

@@ -317,7 +317,7 @@ namespace ICSharpCode.NRefactory.Parser.VB
 							return new Token(Tokens.XmlEndInlineVB, new Location(x, y), new Location(Col, Line));
 						}
 						#endregion
-						if (ch == '<' && (ef.NextTokenIsPotentialStartOfExpression || ef.NextTokenIsStartOfImportsOrAccessExpression)) {
+						if (ch == '<' && ef.XmlAllowed && (ef.NextTokenIsPotentialStartOfExpression || ef.NextTokenIsStartOfImportsOrAccessExpression)) {
 							xmlModeStack.Push(new XmlModeInfo(ef.NextTokenIsStartOfImportsOrAccessExpression));
 							XmlModeInfo info = xmlModeStack.Peek();
 							int x = Col - 1;

src/Libraries/NRefactory/Project/Src/Lexer/VBNet/PushParser.frame

@@ -37,6 +37,7 @@ partial class ExpressionFinder {
 	bool wasQualifierTokenAtStart = false;
 	bool nextTokenIsPotentialStartOfExpression = false;
 	bool readXmlIdentifier = false;
+	bool xmlAllowed = true;
 	bool identifierExpected = false;
 	bool nextTokenIsStartOfImportsOrAccessExpression = false;
 	bool isMissingModifier = false;

src/Libraries/NRefactory/Test/Parser/Statements/SwitchStatementTests.cs

@@ -39,6 +39,20 @@ namespace ICSharpCode.NRefactory.Tests.Ast
 			SwitchSection sec = switchStmt.SwitchSections[0];
 			Assert.AreEqual(0, sec.SwitchLabels.Count);
 		}
+		
+		[Test]
+		public void SpecialCaseStatement()
+		{
+			SwitchStatement stmt = ParseUtilVBNet.ParseStatement<SwitchStatement>("Select Case a\nCase < 50\nCase > 20, < 10\nEnd Select");
+			Assert.AreEqual("a", ((IdentifierExpression)stmt.SwitchExpression).Identifier);
+		}
+		
+		[Test]
+		public void SpecialCaseStatement2()
+		{
+			SwitchStatement stmt = ParseUtilVBNet.ParseStatement<SwitchStatement>("Select Case a\nCase < 50\nEnd Select");
+			Assert.AreEqual("a", ((IdentifierExpression)stmt.SwitchExpression).Identifier);
+		}
 		#endregion
 	}
 }