pyplot/pycall API updates

[stevengj]

PyCall 1.90.0 and PyPlot 2.8.0 are now released, which change o[:foo] and o["foo"] to o.foo and o."foo", respectively, for python objects o.

The old getindex methods still work but are deprecated, so you'll want to put out a new Plots.jl release that uses the new methods and REQUIREs the new versions to avoid having zillions of deprecation messages.

[mkborregaard]

Thanks. Yeah, the disadvantage with Plots' conditional package loading is that we can't depend on different versions of the backend packages. So, we'll tag a Plots 0.24.0 with the change, and everyone will just have to update to the newest PyCall and PyPlot versions to use the backend.

[stevengj]

You can check for e.g. isdefined(PyCall, :_setproperty!) if you want to check explicitly whether the user has a PyCall with JuliaPy/PyCall.jl#517.

[mkborregaard]

Ah, that's nice!
I'm not 100% certain this is needed though - I added #1933 for this, but there was only a single place to fix, and pyplot(); scatter(1:10) works without deprecation warnings on PyCall 1.90.0 and PyPlot 2.8.0 for the released version of Plots.
You wouldn't have some code that will recreate the problem I can use to test?

[mkborregaard]

I'll merge #1933 since it appears harmless. Thanks!

[stevengj]

#1933 doesn't close this. You still have lots of other deprecated usages like pycolors["LinearSegmentedColormap"][:from_list] or pypath["Path"]or pynp["ma"][:masked_invalid]

o["foo"] should be replaced with o."foo".

[mkborregaard]

Oh :-O on it

[daschw]

@stevengj Is there a way to still do something like

letter = axis[:letter]
lfrom, lto = axis_limits(axis)
ax[Symbol("set_", letter, "lim")](lfrom, lto)

with the new API?

[diegozea]

I think you can call getproperty explicitly in those cases: getproperty(ax, Symbol("set_", letter, "lim"))

[daschw]

Thanks a lot @diegozea !

[stevengj]

Note also that in many of these cases you might want to switch from a.foo to a."foo" — if you know you want a PyObject result, it is faster if you skip the automatic conversion.

[daschw]

Thanks!