How does this work when doing pip install .?

[ifiddes]

I am trying to modify miniver to not allow installations that do not properly resolve to a known version by raising an exception. I therefore modified all the places where unknown was returned with a new exception. This works fine for pip install -e ., but not for pip install .

This made me dig deeper, and I am not sure I understand how this is ever possible -- in the case where you are doing pip install ., the first thing pip does is copy the repo to a temporary folder, without the hidden folders, which means the .git folder is no longer present.

I am obviously missing something important here, but how can it be possible for miniver to successfully get the git version during such an install? Do I always have to install with pip install -e . if I am trying to do a local install from a repo?

[jbweston]

Hi Ian,

Sorry for the late reply.

I tried applying this patch to _version.py.
After doing so in a fresh repo with no tags, pip install . and also pip install -e . both error out (which is what we want).
When I add a tag both commands work fine again.

In the case where you are doing pip install ., the first thing pip does is copy the repo to a temporary folder

I took a closer look at the output of pip install . and it seems that it first builds a wheel:

The wheel will already have the version info embedded in it.

Let me know if that patch works for you; if so we could have this be an option when installing miniver.

[jbweston]

I just realized that applying that patch will mean that import mypackage will also fail, which is probably not what you want when developing 😄.

An alternative could be to just have the _build_py and/or _sdist functions error out when the version contains unknown. This would not make pip install -e . error out, unfortunately, but it might be possible to hook into setuptools' develop (which is what pip install -e . runs) to fix this.