> If you disable this block of code everything runs fine (although the tests fail). It's kinda creepy that the NamedTemporaryFile is leaking - it really should

> If you disable this block of code everything runs fine (although the tests fail). It's kinda creepy that the NamedTemporaryFile is leaking - it really shouldn't... My guess is the tempfile is leaking due to the attribute caching here https://github.com/python/cpython/blob/master/Lib/tempfile.py#L480 https://github.com/python/cpython/blob/master/Lib/tempfile.p... . But that doesn't really explain why the file is getting closed twice. (Presuming it's getting closed twice as otherwise the file descriptor wouldn't be reallocated) Edit: realised it's just attaching the closer object to the function not the full object so avoiding this.