Language Server - parseFunction vararg (#28)

( from https://kolmafia.us/threads/ash-language-server-features.26098/post-163765 )
This modifies the logic of parseFunction a bit so that the vararg error checks happen after the variable name was read.
This will allow us to have the full variable + type's location, rather than only the type, once those are implemented.

Additionally, this allows the "Only one vararg parameter is allowed" error message to be reached.

src/net/sourceforge/kolmafia/textui/Parser.java

@@ -726,18 +726,10 @@ private Function parseFunction( final Type functionType, final Scope parentScope
 
 			if ( this.currentToken().equals( "..." ) )
 			{
-				// We can only have a single vararg parameter
-				if ( vararg )
-				{
-					throw this.parseException( "Only one vararg parameter is allowed" );
-				}
 				// Make an vararg type out of the previously parsed type.
 				paramType = new VarArgType( paramType );
 
 				this.readToken(); //read ...
-
-				// Only one vararg is allowed
-				vararg = true;
 			}
 
 			Variable param = this.parseVariable( paramType, null );
@@ -746,19 +738,32 @@ private Function parseFunction( final Type functionType, final Scope parentScope
 				throw this.parseException( "identifier", this.currentToken() );
 			}
 
-			if ( !paramList.add( param ) )
+			if ( vararg )
+			{
+				if ( paramType instanceof VarArgType )
+				{
+					// We can only have a single vararg parameter
+					throw this.parseException( "Only one vararg parameter is allowed" );
+				}
+				else
+				{
+					// The single vararg parameter must be the last one
+					throw this.parseException( "The vararg parameter must be the last one" );
+				}
+			}
+			else if ( !paramList.add( param ) )
 			{
 				throw this.parseException( "Parameter " + param.getName() + " is already defined" );
 			}
 
-			if ( !this.currentToken().equals( ")" ) )
+			if ( paramType instanceof VarArgType )
 			{
-				// The single vararg parameter must be the last one
-				if ( vararg )
-				{
-					throw this.parseException( "The vararg parameter must be the last one" );
-				}
+				// Only one vararg is allowed
+				vararg = true;
+			}
 
+			if ( !this.currentToken().equals( ")" ) )
+			{
 				if ( this.currentToken().equals( "," ) )
 				{
 					this.readToken(); //read comma

test/net/sourceforge/kolmafia/textui/ParserTest.java

@@ -608,15 +608,12 @@ public static Collection<Object[]> data()
 				               "6", ".", "3", ",", "4", ".", "9", ",", "10", ",",
 				               "-", "0", ")" ),
 			},
-			/*{
-				// Is currently trumped by
-				// "The vararg parameter must be the last one"
-
+			{
 				"Basic function with multiple varargs",
 				"void f(int ... a, int ... b) {}",
 				"Only one vararg parameter is allowed",
 				null,
-			},*/
+			},
 			{
 				"Basic function with non-terminal vararg",
 				"void f(int ... a, float b) {}",