Framework build on macOS

[christianbrodbeck]

Currently conda-forge iPython does not launch with the framework build of Python, which means it can't be used for interacting with wxPython applications (for example setting matplotlib backend to wx). If I understand this correctly, it might be possible to fix this with as little as adding:

build:
    osx_is_app: True

and probably adding the python.app dependency.

Test:

In [1]: import matplotlib as mpl

In [2]: mpl.use('wx')

In [3]: from matplotlib import pyplot as plt

In [4]: plt.plot([0, 1])
An exception has occurred, use %tb to see the full traceback.

SystemExit: This program needs access to the screen.
Please run with a Framework build of python, and only when you are
logged in on the main display of your Mac.

[minrk]

Question for people who might understand this better:

Why is this needed for conda Python, but not Python.org's installations? conda Python is a framework build, so I don't entirely see why the entrypoint is relevant, especially when it doesn't appear to matter for other Python builds.

[christianbrodbeck]

There is some discussion here and here.

[ChrisBarker-NOAA]

@minrk: conda python is NOT a framework build, which is the whole issue.

though the "real" solution is to have the conda build on OS-X build the "pythonw" wrapper, rather than trying to hack in a "python.app" shell script .... see other referenced issues.