[enh] add an add_plane convenience method to ClippingPlaneList

[psobolewskiPhD]

References and relevant issues

There is some discussion about this here
https://napari.zulipchat.com/#narrow/stream/212875-general/topic/clipping.20planes.20and.20slicing.20planes

Description

Prior to this PR, if a user wanted to use the experimental clipping planes feature, they had to do the following in the console or script:

from napari.layers.utils.plane import ClippingPlane
cplane = ClippingPlane()
viewer.layers[-1].experimental_clipping_planes.append(cplane)

In this PR, I add a convenience method to ClippingPlaneList called add_plane that will create a ClippingPlane with args/kwargs and then append it to the list, this way it's easier for users to get at this great feature! I also add a test for the new method.

[psobolewskiPhD]

I'm not sure how def add_plane(self, *args, **kwargs) -> None: should be properly annotated. My google-fu was weak? So I just added the type: ignore, advice welcome.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 92.86%. Comparing base (5a42fd9) to head (22e57df).

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #6921      +/-   ##
==========================================
- Coverage   92.96%   92.86%   -0.10%     
==========================================
  Files         618      618              
  Lines       56525    56539      +14     
==========================================
- Hits        52547    52505      -42     
- Misses       3978     4034      +56     

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

[brisvag]

Seems pretty straight forward to me, and it's clearly marked experimental so we don't need to stress about getting the API right. No clue about typing :/

[psobolewskiPhD]

I think if I dropped the ->None: then mypy would also skip it? So maybe that's better?

[brisvag]

yup, better untyped than ignored!

[psobolewskiPhD]

Boo, dropping the None didn't work:
https://github.com/napari/napari/actions/runs/9165440649/job/25198887475?pr=6921#step:5:16

[jni]

@psobolewskiPhD if you can figure out typing I think this could (still!) go into 0.5.0! Maybe @Czaki has some some advice...

[jni]

@psobolewskiPhD the other thing I would do here is maybe add/update a gallery example.

[jni]

typing is still unhappy @Czaki 😢

[Czaki]

@jni fixed

[jni]

Amazing. 😂

[psobolewskiPhD]

Thanks @Czaki ❤️