Hi Oscar,
Thanks for the feedback.
On 07/12/2019 7:37 pm, Oscar Benjamin wrote:
On Sat, 7 Dec 2019 at 06:29, Steven D'Aprano <st...@pearwood.info> wrote:
A million seems reasonable for lines of source code, if we're prepared
to tell people using machine generated code to split their humongous .py
files into multiple scripts. A small imposition on a small subset of
Python users, for the benefit of all. I'm okay with that.
I recently hit on a situation that created a one million line code file:
https://github.com/pytest-dev/pytest/issues/4406#issuecomment-439629715
The original file (which is included in SymPy) has 3000 lines
averaging 500 characters per line so that the total file is 1.5MB.
Since it is a test file pytest rewrites the corresponding pyc file and
adds extra lines to annotate the intermediate results in the large
expressions. The pytest-rewritten code has just over a million lines.
There are two possible solutions here (in the context of PEP 611)
1. Split the original SymPy test file into two or more files and the
test function into many smaller functions.
2. Up the line limit to two million and the bytecode limit to many million.
Note that changing pytest to output fewer lines won't work as we will
just hit the bytecode limit instead.
1. Is this difficult? I wouldn't expect it to be so.
2. Simple, but with a performance impact.
The simplest solution appears to be to just up the limits, but the
problem with that is any costs we incur are incurred by all Python
programs forever. Fixing the test is a one off cost.
When I first tried pytest with this file it lead to a CPython
segfault. It seems that the crash in CPython was fixed in 3.7.1 though
so subsequent versions can work fine with this (although it is slow).
The tests in the file are skipped anyway so I just made sure that the
file was blacklisted in SymPy's pytest configuration.
--
Oscar
_______________________________________________
Python-Dev mailing list -- python-dev@python.org
To unsubscribe send an email to python-dev-le...@python.org
https://mail.python.org/mailman3/lists/python-dev.python.org/
Message archived at
https://mail.python.org/archives/list/python-dev@python.org/message/IUG6EBERWZJKWOF2LJTQJKCUXTJTQXS5/
Code of Conduct: http://python.org/psf/codeofconduct/
_______________________________________________
Python-Dev mailing list -- python-dev@python.org
To unsubscribe send an email to python-dev-le...@python.org
https://mail.python.org/mailman3/lists/python-dev.python.org/
Message archived at
https://mail.python.org/archives/list/python-dev@python.org/message/LSANYP2LXIME52A2M3QXR67MGIXJKDXS/
Code of Conduct: http://python.org/psf/codeofconduct/
