Fix issues in codegen and traversal

[JeremyMoeglich]

This fixes #1460 and #1453

The codegen logic had an issue where it would generate the function for the pipe, but never actually call it.
This changes the codegen logic to create the call, though you should definitely look over this part since I am not too familiar with it

It also ensures proper cleanup before returning in the traversal logic since previously it may leave stale state leading to internal throws.

I added 3 tests that failed previously and now pass

[JeremyMoeglich]

What's the state of review? In #1495 which partially solved the exact same issue it seems like you didn't know about it which makes it seem like this PR was just lost in the past and never looked at.

I would love to be able to switch to the main branch again since I've been on a fork for months now since I run into these issues all over the place in my codebase @ssalbdivad

[ssalbdivad]

Hey you're right this did slip through the cracks. I really appreciate the effort you put into a complex part of the codebase and am very sorry it took so long for me to address your PR- that's the last thing I want for contributors.

I'll get a new version published ASAP and will do a better job next time. Please don't hesitate to ping me if you run into anything in the future.