test(overload): add positive tests for overload

unittest/positive/overload_multi1.decaf

+class A
+{
+	void print ()
+	{
+		Print ( "A.print\n" );
+	}
+}
+
+class B extends A
+{
+	void print ()
+	{
+		Print ( "B.print\n" );
+	}
+}
+
+class F
+{
+	static void f ( class A a, class A b )
+	{
+		Print ( "F: A A\n" );
+		a.print ();
+		b.print ();
+	}
+}
+
+class G
+{
+	static void f ( class A a, class A b )
+	{
+		Print ( "G: A A\n" );
+	}
+
+	static void f ( class A a, class B b )
+	{
+		Print ( "G: A B\n" );
+	}
+
+	static void f ( class B a, class A b )
+	{
+		Print ( "G: B A\n" );
+	}
+
+	static void f ( class B a, class B b )
+	{
+		Print ( "G: B B\n" );
+	}
+}
+
+class Main
+{
+	static void main ()
+	{
+		class A a;
+		a = new A ();
+		class B b;
+		b = new B ();
+
+		F.f ( a, a );
+		F.f ( a, b );
+		F.f ( b, a );
+		F.f ( b, b );
+
+		G.f ( a, a );
+		G.f ( a, b );
+		G.f ( b, a );
+		G.f ( b, b );
+	}
+}
\ No newline at end of file

unittest/positive/overload_single1.decaf

+class A
+{
+	int f ( int a )
+	{
+		return 1;
+	}
+
+	int f ( string a )
+	{
+		return 2;
+	}
+}
+
+class B extends A
+{
+	int f ( int a )
+	{
+		return 3;
+	}
+
+	int f ( bool a )
+	{
+		return 4;
+	}
+}
+
+class Main
+{
+	static void main ()
+	{
+		class A a;
+		a = new A ();
+		Print ( a.f ( 1 ) );
+		Print ( a.f ( "1" ) );
+
+		class B b;
+		b = new B ();
+		Print ( b.f ( 1 ) );
+		Print ( b.f ( "1" ) );
+		Print ( b.f ( true ) );
+	}
+}
\ No newline at end of file

unittest/positive/result/overload_multi1.result

+F: A A
+A.print
+A.print
+F: A A
+A.print
+B.print
+F: A A
+B.print
+A.print
+F: A A
+B.print
+B.print
+G: A A
+G: A B
+G: B A
+G: B B

unittest/positive/result/overload_single1.result

+12324