add a test to check zero index array do not error

[illegalnumbers]

refs GH-21946

• closes #xxxx
• tests added / passed
• passes git diff upstream/master -u -- "*.py" | flake8 --diff
• [na] whatsnew entry

[pep8speaks]

Hello @illegalnumbers! Thanks for updating this PR. We checked the lines you've touched for PEP 8 issues, and found:

• In the file pandas/tests/indexing/test_indexing.py:

Line 865:80: E501 line too long (82 > 79 characters)

Comment last updated at 2019-03-24 02:57:47 UTC

[codecov]

Codecov Report

Merging #25856 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master   #25856   +/-   ##
=======================================
  Coverage   91.45%   91.45%           
=======================================
  Files         172      172           
  Lines       52892    52892           
=======================================
  Hits        48373    48373           
  Misses       4519     4519

Flag	Coverage Δ
#multiple	90.02% <ø> (ø)	⬆️
#single	41.81% <ø> (ø)	⬆️

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Δ = absolute <relative> (impact), ø = not affected, ? = missing data
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[codecov]

Codecov Report

Merging #25856 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master   #25856   +/-   ##
=======================================
  Coverage   91.45%   91.45%           
=======================================
  Files         172      172           
  Lines       52892    52892           
=======================================
  Hits        48373    48373           
  Misses       4519     4519

Flag	Coverage Δ
#multiple	90.02% <ø> (ø)	⬆️
#single	41.81% <ø> (ø)	⬆️

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 6e0f9a9...9c970d8. Read the comment docs.

[jreback]

this is already fully covered by #24924