libtbx_refresh runs with setuptools in "legacy_editable" mode

[dwpaley]

In pypa/setuptools#3265 (merged in setuptools 64), the default behavior of pip install --editable changed. This broke the libtbx.refresh scripts that previously placed an entrypoints file in modules, e.g. modules/dxtbx/src/dxtbx.egg-info/entry_points.txt.

We restore the legacy behavior by setting an environment variable SETUPTOOLS_ENABLE_FEATURES=legacy_editable before running the libtbx_refresh scripts. This allows using the current setuptools, otherwise we would have to pin it again to <=63.

[ndevenish]

What has physically changed with the layout? It tries to put the .egg-info in a different place now?

The documentation changes seem to be pushing people towards using virtual environments. I know cctbx has resisted this for some time (hence the whole bespoke engineering around read-only installs), but is it going to end up being unavoidable if they drop the legacy setting?

[dwpaley]

Hi Nick, the new editable install doesn't create egg-info directories:

dwpaley@dials:/dev/shm/dwpaley/20221012
$ libtbx.refresh
[...]
$ find . -name dxtbx.egg-info
[nothing]
$ find . -name entry_points.txt |grep dxtbx
./build/dxtbx/lib/python3.9/site-packages/dxtbx-3.12.dev0.dist-info/entry_points.txt

I guess a more maintainable fix would be to fix the python environment so the entrypoints files are discovered in their new location? @bkpoon mentioned possibly installing in build instead of build/dxtbx etc.