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Build # 57

Build Type

Pull #8

travis-ci

Committed by web-flow

Commit Message

fix subprocess pipe hanging issue

Just calling `.wait()` without reading stdout can result in the
process deadlocking when the pipe fills up.

We could call `.communicate()`, which ensures that it all gets read,
but has its own risk of memory filling up because it buffers it all:
https://docs.python.org/2/library/subprocess.html#subprocess.Popen.communicate

Instead, we just loop over it, reading line by line until it hits a
`StopIteration`.

I do not have a unit test for this bug, unfortunately. It's a tricky
interaction between python and the system that it's running on and
would likely be a flakey test at best. Furthermore, reproducing the
bug and successfully testing for it would involve detecting that the
program had hung, and that gets tricky (halting problem and all).

Pull Request Pull Request #8: fix subprocess pipe hanging issue

Run Details

3 of 3 new or added lines in 1 file covered. (100.0%)

148 of 161 relevant lines covered (91.93%)

0.92 hits per line