A pattern emerged quickly among the discussions that, according to these conversations, makes a Mary Sue test exceedingly short and simple. So I present one.
Instructions: keep 2 columns of tallies for answer a or answer b.
1) What is the character’s gender identity?
2) Is the character competent in more than 1 thing not traditionally a feminine role/activity/interest?
3) Is the character attractive?
Time to tally up!