Merge pull request #4884 from Vogel612/fix/lineSpecialForm

Fixes parser rule for Line special-form syntax.

Author: retailcoder

Rubberduck.Parsing/Grammar/VBAParser.g4

@@ -571,7 +571,13 @@ withStmt :
 ;
 
 // Special forms with special syntax, only available in VBA reports or VB6 forms and pictureboxes.
-lineSpecialForm : expression whiteSpace ((STEP whiteSpace?)? tuple)? MINUS (STEP whiteSpace?)? tuple whiteSpace? (COMMA whiteSpace? expression)? whiteSpace? (COMMA whiteSpace? lineSpecialFormOption)?;
+// lineSpecialFormOption is required if expression is missing
+lineSpecialForm : expression whiteSpace ((STEP whiteSpace?)? tuple)?
+    whiteSpace? MINUS whiteSpace?
+	(STEP whiteSpace?)? tuple whiteSpace?
+	(COMMA whiteSpace? expression? whiteSpace?)?
+	(COMMA whiteSpace? lineSpecialFormOption)?
+;
 circleSpecialForm : (expression whiteSpace? DOT whiteSpace?)? CIRCLE whiteSpace (STEP whiteSpace?)? tuple (whiteSpace? COMMA whiteSpace? expression)+;
 scaleSpecialForm : (expression whiteSpace? DOT whiteSpace?)? SCALE whiteSpace tuple whiteSpace? MINUS whiteSpace? tuple;
 pSetSpecialForm : (expression whiteSpace? DOT whiteSpace?)? PSET (whiteSpace STEP)? whiteSpace? tuple whiteSpace? (COMMA whiteSpace? expression)?;