Cosmo rename arg for io

[nstarman]

Adding an option to remap symbols in input and output of a cosmology.
This should be helpful for #14701.

[github-actions]

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[github-actions]

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[mhvk]

@nstarman - Overall, I like the idea but found the large number of unrelated code and docstring changes distracting and ended up running out of time. So, mostly a few grumpy comments inline, plus a slightly larger question: don't we have something like this already in the general IO? I tried looking and couldn't find it, so probably not, but let me ping @taldcroft regardless, since perhaps this option to rename things would be something we should support more generally.

My mai

[pllim]

but found the large number of unrelated code and docstring changes distracting

I did a drive-by glance but gave up for the same reason too. It was unclear to me why these are necessary for the renaming process.

[nstarman]

Overall, I like the idea but found the large number of unrelated code and docstring changes distracting and ended up running out of time.

Apologies for the constellation of changes surrounding the main portion of the PR. These changes arose because when I added the docstring for the new argument I wanted to make sure I got the format correct, following numpydoc to the T. I found that the docstring was incorrectly implemented 😲 and rather than mixing styles within one docstring, I fixed the relevant docstrings.

[eerovaher]

@mhvk wrote:

...don't we have something like this already in the general IO? I tried looking and couldn't find it, so probably not, but let me ping @taldcroft regardless, since perhaps this option to rename things would be something we should support more generally.

I also think renaming things at the astropy.io level could be useful. For example, I would find it convenient if I could work in Python with a Table with columns named "ra" and "dec", but when I write a LaTeX file using astropy.io I might want the column names to appear as "$\alpha$" and "$\delta$". So if there is a way of implementing renaming things so that both astropy.table and astropy.cosmology would benefit then that should be considered. I am not familiar enough with astropy.io to know if this would be simple to achieve or not, so it would be good to know what @taldcroft thinks.

[nstarman]

@eerovaher, I agree, but m any of the Cosmology I/O methods do not rely on Table, so lacking prior art from table, I think this PR is a good place to start.

[eerovaher]

Overall I think this is a good idea, but I do have some suggestions regarding the implementation.

[nstarman]

Thanks @eerovaher for the detailed review!

[nstarman]

I squashed commits, added and modified tests, added to the Examples in the docstring, and put in a "whatsnew".

[eerovaher]

I have just a few remarks regarding the documentation in this pull request. But I should also point out that the astropy.cosmology I/O documentation isn't being edited at all.

[eerovaher]

I'm happy with all the changes this pull request currently makes, but the new feature still has to be documented in astropy.cosmology I/O documentation.

[eerovaher]

I have a few small requests regarding the documentation. I think we can merge when they are addressed.

[eerovaher]

Merging the pull request that renamed astropy.cosmology.io to astropy.cosmology._io has created merge conflicts that need to be solved, but other than that this looks good.

[nstarman]

Yikes, but failures are unrelated.

[pllim]

numpy 1.25 is released but h5py didn't catch up. Annoying...

[eerovaher]

The deprecation warnings caused by h5py have been dealt with on main, so I suggest rebasing to allow all the CI tests to succeed.

[eerovaher]

I'd like to merge, but the change log entry CI check is stuck. @pllim, what's the best way to proceed?

[pllim]

Best way was probably what you did. I merged it. 😉

Sigh, if only there is a better way to run change log check... it gets stuck more and more often now.

[pllim]

Thanks, all!

[mhvk]

I usually just turn labels on and off so it runs again (and nothing else does), but it is indeed a bit of a pain.

[pllim]

The problem here is we rely on Actions, so it competes with other jobs and sometimes GitHub might flag it as spammy.