TST: test for GH2623, object in frame upconverting a datetime64[ns] in another column

[jreback]

this is tests only at #2623 is covered by other PRS

[wesm]

You can feel free to push commits like this directly.

[jreback]

yep, makes sense

[ghost]

if you merge branches manually and push, please use merge --no-ff, to ensure a merge commit
that packages up related commits into a well-defined block. no need if it's something small.

[jreback]

how is that different from pushing to my local branch then auto merging? which generates the merge commit
we do want the merge commit , right?

[ghost]

no difference, it's just the command line equivalent of the greenbutton.
for a PR with serveral coupled commits, I prefer a merge commit yes.
But I often push singles straight to master.

[jreback]

ok that's great thanks