BUG: .rename* not treating Series as mapping

[TomAugspurger]

Closes #12623

I added com.is_dict_like in #11980
and failed to use it for the rename method. Using that now and did
some refactoring while I was in there. Added more tests for rename.

[TomAugspurger]

I might remove or rename core._is_scalar_or_list_like. It doesn't seem like a well-defined or clear check...

[jreback]

@TomAugspurger btw, make sure you are rebased on current master. dateutil=2.5.0 flowed thru and broke some tests and I just fixed in (maybe 2 hrs ago)

[jreback]

yeah I think lib.isscalar(...) or com.is_list_like(...) is more clear

[TomAugspurger]

com.is_list_like(dict) is True, and I need to treat dicts differently than lists.

But if we're going to be raising on Series.rename(list) anway, I won't have to worry about lists at all...

[jreback]

maybe tests both dict and Series (for the renamer), and anything else that could be there (e.g. callable)? you prob already have these tests......

d = {1: 10, 2: 20}
for value in [ d, Series(d) ]:
     ....

for

[TomAugspurger]

These should all covered by test_generic now. Initially I didn't understand how test_generic was setup, so I added the test here. I think these tests are all redundant, and could remove them this one and test_rename above, but I always worry about deleting tests :)

[jreback]

cool np. yeah. hard to stop the propogation of tests :)

[TomAugspurger]

Ok, the tests for the different possible arguments are here. I simplified the stuff with is_scalar_or_mapping to just do the check in the code. Should be clearer now, but a bit less DRY.

[jreback]

thanks @TomAugspurger