I inserted importlib.invalidate_caches() instead of os.sync() and at a glance, it seems to have fixed it.
Big thanks Paul! pon., 12 mar 2018 o 11:00 użytkownik Paul Moore <p.f.mo...@gmail.com> napisał: > On 12 March 2018 at 09:12, Arkadiusz Bulski <arek.bul...@gmail.com> wrote: > > Hi, > > > > For the record, I am the developer of Construct library. And the question > > relates to it. > > https://construct.readthedocs.io/en/latest/# > > > > I have an issue of Travis failing randomly at test cases. The cause is > > always __import__ failing to import a dynamically generated code. Library > > generates a string, saves it to a file (closes the file too), then > > __import__ it. I dont think there is anything wrong with the (generated > > imported) code itself. It seems like its some sort of issue with the > Python > > runtime (or filesystem) not detecting the file because it was created > only > > a moment ago. I tried to solve it by adding os.sync() between writing the > > file and importing it, but it seems to have only decreased the error > rate, > > not solved it. Frankly, this is a heisenbug. Re-running the Travis job > > usually fixes it. Its random and happens very rarely. I havent pinpointed > > it to any particular version of CPython or Pypy (although I dont remember > > it ever happening on Pypy). > > > > An example: > > https://travis-ci.org/construct/construct/jobs/352213556 > > > > The code in question: > > > https://github.com/construct/construct/blob/d9c645ed0a75b5a2b64318113cf69cac822fd8f5/construct/core.py#L402-L414 > > > https://github.com/construct/construct/blob/d9c645ed0a75b5a2b64318113cf69cac822fd8f5/construct/core.py#L179-L180 > > The import system caches os.stat information, so it's possible that if > you're creating the file and then relatively quickly doing the import, > there may be some cache effect going on (granularity of file > modification timestamps?) I don't know the details, but it might be > worth looking in that area... > > Paul > -- ~ Arkadiusz Bulski ~ tel 503 357 111 lub WhatsApp/Telegram -- https://mail.python.org/mailman/listinfo/python-list
