CI: Failure on Appveyor Master

[TomAugspurger]

https://ci.appveyor.com/project/pandas-dev/pandas/build/job/0y6fvce0al2yax06?fullLog=true#L1989

cc @WillAyd

Maybe #21066 was related? Not sure how though. Looking now.

[WillAyd]

Hmm strange indeed. I have a hard time thinking that change would be the cause (it was passing fine up until the last commit) but who knows.

I recall there being a similar issue with the Mac builds and in the same area of testing (see #19984). I'm not sure there was ever a real resolution to that one outside of time (?)

No chance we changed anything with the build environment right? I see other changes are passing...

[TomAugspurger]

Yeah, it's possible this was a one-ooff (two-off?) fluke. I'm waiting to debug further till we see additional failures.

…

On Thu, May 17, 2018 at 10:13 AM, William Ayd ***@***.***> wrote: Hmm strange indeed. I have a hard time thinking that change would be the cause (it was passing fine up until the last commit) but who knows. I recall there being a similar issue with the Mac builds and in the same area of testing (see #19984 <#19984>). I'm not sure there was ever a real resolution to that one outside of time (?) No chance we changed anything with the build environment right? I see other changes are passing... — You are receiving this because you authored the thread. Reply to this email directly, view it on GitHub <#21102 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/ABQHIiRaKvrANC9CKniG9sglVLGYjlRoks5tzZOLgaJpZM4UDCo2> .

[WillAyd]

I did notice there's one instance in common.py where we open a file handle but never explicitly close it. It's tough to say since any information about the ResourceWarning is getting suppressed but wonder if the below line is the offender?

pandas/pandas/tests/io/parser/common.py

Line 57 in d623ffd

handle = open(self.csv_shiftjs, "rb")

[jreback]

that looks like an issue (independent of other things)

[david-liu-brattle-1]

I think I got the same problem in #21111 (Commit #ce02a40)
https://ci.appveyor.com/project/pandas-dev/pandas/build/1.0.14243/job/c3wslf40egfq4ksw