[bug] type checker makes mistakes with `ClassSelf`

[mrodz]

Snippet Responsible

class A {
    fn assoc(self) -> Self? {
        return self
    }
}

a = A()

type B A
type C B

take_a = fn(in: C) {
    print in
}

take_a((a.assoc()) or A()) 

Stack Trace of Error

[ Trace ] INIT Virtual Stack at MODULE
[ Debug ] pre-walk ".\\try_to_crash.ms"
[ Debug ] registering new file ".\\try_to_crash.ms" (File { declarations: RefCell { value: [] }, location: ".\\try_to_crash.mmm", exports: RefCell { value: [] }, public_types: RefCell { value: {} }, compiled: CompilationLock(Cell { value: false }) }) -- Adding to: []
[ Trace ] Virtual Stack PUSH: Class <UNKNOWN> -> No
[ Trace ] + assoc: fn() -> Self?
[ Trace ] Virtual Stack POP
[ Trace ] in scope Module, adding type A = A
[ Trace ] formally aliasing `B` = A
[ Trace ] + B: A
[ Trace ] in scope Module, adding type B = B
[ Trace ] Gen. mod ".\\try_to_crash.ms" -- adding type TypeAlias
[ Trace ] formally aliasing `C` = B
[ Trace ] in scope Module, adding type C = C
[ Trace ] Gen. mod ".\\try_to_crash.ms" -- adding type TypeAlias
[ Trace ] Gen. mod ".\\try_to_crash.ms" -- skipping value
[ Info ] DONE preloading module .\try_to_crash.ms
[ Info ] + mod "./try_to_crash.ms" ModuleType { exported_members: RefCell { value: [] }, public_types: RefCell { value: {} }, name: ".\\try_to_crash.ms" }
[ Info ] + finished preload of ".\\try_to_crash.ms"
[ Trace ] Virtual Stack PUSH: Class <UNKNOWN> -> No
[ Trace ] + assoc: fn() -> Self?
[ Trace ] + A: A
[ Trace ] class A { ... }
[ Trace ] Virtual Stack PUSH: fn(???) -> Should(Optional(Some(ClassSelf)))
[ Trace ] + self: Self
[ Trace ] Virtual Stack POP
[ Trace ] Virtual Stack POP
[ Trace ] in scope Module, adding type A = A
[ Trace ] + A: A
[ Trace ] + a: A
[ Trace ] formally aliasing `B` = A
[ Trace ] + B: A
[ Trace ] in scope Module, adding type B = B
[ Trace ] formally aliasing `C` = B
[ Trace ] in scope Module, adding type C = C
[ Trace ] Virtual Stack PUSH: fn(???) -> Void
[ Trace ] + in: C
[ Trace ] Virtual Stack POP
[ Trace ] + take_a: fn(C)
[ Error ] ./try_to_crash.ms:16:23 > The `or` portion of this unwrap must yield `Self`, but `A` was found > "A()"
  --> ./try_to_crash.ms:16:23
   |
16 | take_a((a.assoc()) or A())
   |                       ^-^
   |
   = The `or` portion of this unwrap must yield `Self`, but `A` was found
Error: Did not compile successfully (1 Error)

Expected Behavior

Allow this or fallback, because it is correct.

Any ideas where MScript breaks?

• [ ] Bytecode Interpreter
• [X] Compiler
• [ ] Optimizer
• [ ] Not Sure (It's okay!)
• [ ] Other: please explain

Brain Dump (Optional)

• ClassSelf is not being handled by the typechecker eq_complex() correctly