pip-lock breaks in debug build of Python 3

[embray]

With SAGE_PYTHON3=yes, I ran

SAGE_DEBUG=yes ./sage -f python3

and now when I try to rebuild Cython on top of that with

SAGE_DEBUG=yes ./sage -f cython

I get

[cython-0.26] gcc version 4.8.4 (Ubuntu 4.8.4-2ubuntu1~14.04.3)
[cython-0.26] ****************************************************
[cython-0.26] Unable to find pgen, not compiling formal grammar.
[cython-0.26] Uninstalling Cython-0.26:
[cython-0.26]   Successfully uninstalled Cython-0.26
[cython-0.26] sys:1: ResourceWarning: unclosed file <_io.TextIOWrapper name='/home/embray/src/sagemath/sage/local/var/lock/pip3.lock' mode='w+' encoding='ANSI_X3.4-1968'>
[cython-0.26] Cannot uninstall requirement Cython, not installed
[cython-0.26] sys:1: ResourceWarning: unclosed file <_io.TextIOWrapper name='/home/embray/src/sagemath/sage/local/var/lock/pip3.lock' mode='w+' encoding='ANSI_X3.4-1968'>
[cython-0.26] Error installing Cython

Same if I try reinstalling Cython with SAGE_DEBUG=no. Just to be sure I rebuild python3 without debug, and was able to install Cython again with no problem, so it really seems to be something about the specific combination of SAGE_DEBUG=yes and python3.

Component: python3

Issue created by migration from https://trac.sagemath.org/ticket/23788

[embray]

comment:1

I think this is some bad combination of hacky code (that I wrote) IIRC in sage-pip-install, pip-lock, and Python 3 with debug flags and hence more chatty with ResourceWarnings.

[embray]

comment:3

#23397, which rewrote the pip-lock command, appears to fix this. The new sage-flock script doesn't have the resource leak (actually it sort of does but Python doesn't complain about it since that version of the script uses exec, anyways it doesn't matter). So if that gets merged we can close this ticket as fixed.

[fchapoton]

comment:5

can we close this one now that #23397 is on the way ?

[embray]

comment:6

Yes, thank you for reminding me.