My "Litmus Test" with Friends

Every now and then we come to a fork in the road with certain people. We ask ourselves, "Do I want to keep pursuing this friend? Do I want this friendship to flourish?" For most people, the answer will be obvious to us.
But for some, we can argue both sides. Has nothing to do with whether or not that person is a good person or not, just if it they are someone you want to put more effort into.
Have you ever heard of a litmus test?
Here's the internet's definition: LITMUS TEST: something (such as an opinion about a political or moral issue) that is used to make a judgment about whether someone or something is acceptable. Ex: The party is using attitudes about gun control as a litmus test for political candidates.
Sounds kind of harsh and my own litmus test with friends isn't "who is acceptable" it's more do I want to pursue kind of thing.
So this is mine. If I really can't decide if I want to pursue a friendship... I picture that person showing up at my house at a time when it is a complete DIASTER. Like very very messy and they come inside.
Do I feel calm and don't really care that they see my house that way?
Or do I feel embarrassed and mortified that they'd see my house that way?
If the answer is the latter then I likely am a bit performative with that person and we don't the energy needing to perform for our friends.
If the answer is I feel totally okay with them seeing my house that way, that's a good clue I can be FULL CAPS myself with them and that's a person I like to pursue and be around.
This happened to me in real life P.S. I once had a best friend who was an amazing person, but I did often feel performative around her. And whether she judged me or didn't-- I always FELT like she did.
But we had so much history! I genuinely loved her and never understood why my guard stayed up a bit wth her. We'll call her Best friend A.
On one of my birthdays, Best Friend A and another best friend of mine (Best Friend B) showed up at my apartment in San Francisco to surprise me. I hate surprises... but I know it was done out of love. ;)
Anyway- I had been massively depressed leading up to that day. Like one of the worst depressions I had ever been in. My room was a DIASTER. I mean it was baaaaad lol.
I remember being HORRIFIED that Best Friend A saw my room that way. I mean I was making excuses out of the wazoo and just so so upset she saw my room in that state. Like physically felt ill.
Best Friend B- I didn't even think twice haha. I felt no need to explain anything to her and just felt very whatever about her seeing my a room a mess.
Later on in life Best Friend A ended up doing a really extravagant not nice thing to me. She apologized months later but I've since let our friendship fizzle out. She's a great person but our collective vibe together was never comfortable and easy for me. It wasn't good for me either.
I think back to that day and I'm like--- Foreshadowing!!
So that's my litmus test these days! I imagine that scenario with any given friend and then evaluate how I feel!
Would love to hear one of your litmus tests.