Hello, a few things: 1) Yesterday we ran into a problem where a transitive dependency upgrade dropped python 2 support and broke our stuff, similar to the issue we had with

pytest

and

more-itertools

. In this case it was with

tornado

. We ended up making the affected target "depend" on

tornado

while pinning

tornado

in our requirements file to an older version. Is there a better way to deal with this?

At the moment this seems to be the best idiom to manage Py2 only compatibility: https://github.com/pantsbuild/pants/pull/7296/files. Note this means Py3 can float, whereas Py2 must be less than the bad version. You may want to instead always use the exact same version no matter what, in which case you would remove the

python_version < 3

. I don’t believe it should be necessary to add the dependency to the BUILD file, but haven’t tested this. Does it appear so when testing?

yeah. In our case, we pinned

tornado

to the version we want, but before we explicitly required it from our build target, that version pinning didn't seem to be respected.