REF: Convert test_hashing to pytest idiom
Hello @gfyoung! Thanks for updating the PR.

 - There are no PEP8 issues in the file [`pandas/tests/util/test_hashing.py`](https://github.com/gfyoung/pandas/blob/77f7ac87b9b71f132d9a36a6ecd789698f446db7/pandas/tests/util/test_hashing.py) !



##### Comment last updated on November 30, 2018 at 06:21 Hours UTC # [Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/24009?src=pr&el=h1) Report
> Merging [#24009](https://codecov.io/gh/pandas-dev/pandas/pull/24009?src=pr&el=desc) into [master](https://codecov.io/gh/pandas-dev/pandas/commit/dc8d35aa53d496b651f5e1ab4cb2604e9f7236c7?src=pr&el=desc) will **not change** coverage.
> The diff coverage is `n/a`.

[![Impacted file tree graph](https://codecov.io/gh/pandas-dev/pandas/pull/24009/graphs/tree.svg?width=650&token=eZ4WkYLtcO&height=150&src=pr)](https://codecov.io/gh/pandas-dev/pandas/pull/24009?src=pr&el=tree)

```diff
@@           Coverage Diff           @@
##           master   #24009   +/-   ##
=======================================
  Coverage   92.31%   92.31%           
=======================================
  Files         161      161           
  Lines       51549    51549           
=======================================
  Hits        47586    47586           
  Misses       3963     3963
```

| Flag | Coverage Δ | |
|---|---|---|
| #multiple | `90.7% <ø> (ø)` | :arrow_up: |
| #single | `42.44% <ø> (ø)` | :arrow_up: |


------

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> Powered by [Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/24009?src=pr&el=footer). Last update [dc8d35a...dfa24a8](https://codecov.io/gh/pandas-dev/pandas/pull/24009?src=pr&el=lastupdated). Read the [comment docs](https://docs.codecov.io/docs/pull-request-comments).
 @jreback @TomAugspurger : Addressed the comment above, and all is still green.  PTAL. LGTM. Instead of the index fixture you could also just call each of `index=False` and `index=True` in `_check_equal`, but either way works for me. > Instead of the index fixture you could also just call each of index=False and index=True in _check_equal, but either way works for me.

Thought about it.  Just wanted something a little more modular.  Thanks for noticing the bug though!