Prune setup.cfg some more (#12059)

* Remove `trial` section from setup.cfg

This was added in the initial commit from 2014. I can't see that it does
anything. Maybe it's there so that you can run `trial` without any extra
args, but if I do that then I just get the `--help` message.

* Move flake8's config to its own file

1 files changed, 11 insertions, 0 deletions

diff --git a/.flake8 b/.flake8
new file mode 100644

index 0000000000..acb118c86e
--- /dev/null
+++ b/.flake8
@@ -0,0 +1,11 @@
+# TODO: incorporate this into pyproject.toml if flake8 supports it in the future.
+# See https://github.com/PyCQA/flake8/issues/234
+[flake8]
+# see https://pycodestyle.readthedocs.io/en/latest/intro.html#error-codes
+# for error codes. The ones we ignore are:
+#  W503: line break before binary operator
+#  W504: line break after binary operator
+#  E203: whitespace before ':' (which is contrary to pep8?)
+#  E731: do not assign a lambda expression, use a def
+#  E501: Line too long (black enforces this for us)
+ignore=W503,W504,E203,E731,E501