build uninstalls setuptools in a venv

[henryiii]

When you run from inside a venv (in my case, a venv inside conda), then python -m build uninstalls setuptools after running python -m build.

And then, on a second run, it immediately breaks, even with setuptools listed in the requires clause (assuming it is needed for ensurepip, perhaps?)

python3 -m venv venv
. venv/bin/activate.fish
python -m pip install build
python -m build
# setuptools is now gone
python -m build
ERROR Backend 'setuptools.build_meta' is not available

Probably closely related to #97 . I am in the same anaconda python3.7 env described in #108, only now with a "setuptools>=42" requirement.

[FFY00]

Yeah, sorry about that 😕

Can you try #99 and see if it fixes it for you? I will come back to it this month and try to get it finally merged.

[gaborbernat]

This should no longer be the case with the new isolated build methods.