Hiding code that was not hit in the editor

[jcmorrow]

This is something that I would love when I'm debugging library code, where I suspect that a particular bug is happening in a particular file, but I don't know that file super well. Being able to look through only the parts of that file that actually ran during this replay, would make it much easier to narrow down where I should be placing my breakpoint. I don't know if CodeMirror has folds, but it seems like a natural way to do this might be folds similar to what you see in github commit summaries.

[jonbell-lot23]

100%. I've been thinking about this for a whole year. Sometimes I know the codebase really well. But other times I'm overwhelmed and confused and I need help finding exactly this sort of data.

[jonbell-lot23]

@jcmorrow we discussed this in product office hours last week, I believe.

Where did we net out? I think I recalled that this was doable? And I think I saw someone say we're working on it?

[jcmorrow]

I have been working on it! It was a bit of a stretch for me and required me to learn a bunch of new things, so it took a bit longer than expected, and there are still 1 or 2 things that I need to clean up about it (though there are PR's
here and here. I've been calling the feature Live Code Analysis [credit to Dan for the name]).

[markerikson]

given my first two days on this product, I suddenly really want this feature right now :)

[jonbell-lot23]

(nod nod) Excellent. I'm excited that we're to the point where the burden of proof is on why a person wouldn't want this rather than why they would. If it's too hard in the code, that's one thing. If it breaks something else, that's a fair reason not to do it.

But it sounds like we can do it, which I think it's going to be a really big deal for the sorts of debugging I find myself doing. And apparently I'm not alone!

[jcmorrow]

I think it has a lot to offer in the "dive into a foreign code base" use-cases for Replay.

[jonbell-lot23]

And when you're not great at debugging, everything (even your own project) is a foreign codebase 😂