BUG: turn member descriptor attributes into links

[mattip]

This turns the member descriptors attributes into links, see for instance the member descriptors of numpy.broadcast nd, ndim, and numiter which were inlined, not linked.

I originally got to this since the documentation of those descriptors has an Example section. Inlining it rather than linking causes sphinx to complain that there is more than one Example section.

I am not sure how to write a test for this, as it requires a c-extension to define the member descriptors.

Perhaps this code could be refactored to check for a positive result, not a negative one

[jnothman]

You could test non-regression on numpy itself, if available. Or is there a memberdescriptor in the standard library? Does namedtuple produce these? (Shooting in the dark)

[mattip]

I tested this on NumPy, it rendered the autosummary methods of numpy.broadcast.{nd, ndim, numiters} as links. namedtuple is pure python but there are memberdescriptors in _codecs. What would a test that uses a .. autosummary:: \n :toctree: look like?

[jnothman]

I suppose we would ideally check the doctree of the parsed rest. We don't have tests like that. I'm okay with this sans test.

[mattip]

is there something more I should do to get this merged?

[jnothman]

I forget we don't demand two approvals here

[jnothman]

Thanks

[eric-wieser]

Nice catch!