Test 2 Stein tie

src/test/c/test_SchereSteinPapier.c

@@ -23,3 +23,16 @@ void test_SchereSteinPapier_Tie_Schere(void)
 	/* assert */
 	TEST_ASSERT_EQUAL_INT(expected, actual);
 }
+
+void test_SchereSteinPapier_Tie_Stein(void)
+{
+	/* arrange */
+	int expected = -1;
+	int actual;
+
+	/* act */
+	actual = game('2', '2');
+
+	/* assert */
+	TEST_ASSERT_EQUAL_INT(expected, actual);
+}