GeezerVison

@alexshoe Can you document the full API for the new properties in this PR description? Basically just the info that's in the plot schema.

@alexshoe Can you remove the image test?

You can make a Codepen and link it in the PR description for testing purposes, but this feature doesn't require adding an image test to the test suite.

@alexshoe Thanks for the updates, I'll take another pass tomorrow

@emilykl thanks for the comments! I addressed most of the things you flagged but re: the comments on reducing duplication: I think the seperate functions are different enough that merging them into a new helper function and adding new branching logic could make more difficult to read. Maybe you can help me outline your vision for how to clean these funcitons up?

That said, @alexshoe I can't see any reason why the titleclick property shouldn't be supported for pie charts.

Yeah, agreed that pie charts should be supported for this feature eventually. The reason I left it out for now is that pie visibility is different from other trace types in that it uses hiddenlabels rather than a per-trace visible property. Legend group title clicking is also disabled for pie-like traces and it would be a lot more work to support both legend title and group title toggling for pies. I felt like it was a bit out of scope for this Kobold deliverable and that maybe we could write-up an issue for a follow-up. Would that be ok?

As long as it's clear in the docs / attribute descriptions where these features don't currently work for pies, I think it's fine to omit that. Not just the mechanics but also the purpose of hiding pie slices is pretty different from hiding traces, so we should think clearly about it and not necessarily feel bound by decisions we made here.

I see a subtle bug - might be preexisting behavior but to register it: In your original codepen, clicking on the group title Group C does nothing, even though it gets cursor: pointer that implies it's active (unlike Group A and Group B which have the default pointer that implies they are not clickable). But if you remove legend.groupclick="toggleitem" - ie the first legend, making Group A and Group B clickable, Group C becomes clickable too.

@alexcjohnson thanks for discovering that. The object for group titles was missing the legend property, so the click handler fell back to the first legend and picked up the wrong groupclick settings. Added the missing property and now it works correctly. I'll update the codepen with the latest build too

Woohoo!!! Congrats on the merge — excited to see it go live :)