chore: get rid of UnsetMarker (ts challenge)

[KATT]

Describe the feature you'd like to request

UnsetMarker is a Symbol and our way of defining that something is unset.

We mark procedures' inputs etc as in its initial state.

It's a lot easier to do extends UnsetMarker than extends undefined etc given that undefined is actually a valid value.

Describe the solution you'd like to see

I am not sure we need it. There might be a neater way?

The challenge is to search through the codebase for UnsetMarker and try to get rid of it.

Describe alternate solutions

Not doing it. It might not be worth caring about

Additional information

It was added as a shortcut to some type of issues that I can't remember.

👨‍👧‍👦 Contributing

• 🙋‍♂️ Yes, I'd be down to file a PR implementing this feature!

[omermizr]

Hey @KATT, first off I wanna say I love this project and keep up the good work!

I dug through the codebase for references of UnsetMarker and here is my 2 cents:

1. It is possible and fairly easy to remove UnsetMarker in favor of undefined, but I'm not sure it'd be the right approach. It would make it impossible to differentiate between an unset state, and someone explicitly wanting undefined as a value.
   While I can't think of a real-world use-case right now, I still think it's a good idea to be explicit about the default state. Here a (somewhat contrived) example:

   t.procedure.output(z.undefined()).query(() => 'foo'); // should error because 'foo' is not undefined
   

2. We can eliminate the runtime symbol and just use a type symbol.
3. I don't see a real issue with using UnsetMarker internally, however it's not ideal if it bleeds into user applications, which leads me to;
4. There is currently a bug where a procedure with no inputs will receive an UnsetMarker as the input to the query/mutation etc.

I'd be happy to submit a PR for 2 and 4 if you decide that's the direction you wanna go in :)

[KATT]

1. Won't work due to the fact that undefined is a possible input and sometimes we need to distinguish between explicit undefined and set undefined
2. I think the symbol is tree shaken already - it's at least designed in a way where it shouldn't be possible to import it externally
3. Fair, it might be a non issues!
4. Oh shit, I didn't know, could you make a failing test that shows this?

[omermizr]

1. Exactly
2. 👍
3. 👍
4. Here you go: fix: do not leak UnsetMarker to query input #3614. It's just the test for now, but I can add a fix too

[KATT]

I'll just close this as a non-issue for now. Nice it led to you highlighting that issue, @omermizr, tyvm!