Installation with pip fails if setuptools_scm not installed

[arnaudrichard]

Using python 3.11.2 on Windows, and pip 23.0.1 I tried many pip options to install mplcursors due to misleading warnings until I found out "setuptools_scm" was missing. Maybe there's a way to specify this dependency in the package ?

[anntzer]

Can you post the output of pip install -v mplcursors?

[arnaudrichard]

C:\Users\richarda>pip install -v mplcursors
Using pip 23.0.1 from C:\Users\richarda\AppData\Local\Programs\Python\Python311\Lib\site-packages\pip (python 3.11)
Requirement already satisfied: mplcursors in c:\users\richarda\appdata\local\programs\python\python311\lib\site-packages (0.5.2)
Requirement already satisfied: matplotlib>=3.1 in c:\users\richarda\appdata\local\programs\python\python311\lib\site-packages (from mplcursors) (3.7.1)
Requirement already satisfied: contourpy>=1.0.1 in c:\users\richarda\appdata\local\programs\python\python311\lib\site-packages (from matplotlib>=3.1->mplcursors) (1.0.7)
Requirement already satisfied: cycler>=0.10 in c:\users\richarda\appdata\local\programs\python\python311\lib\site-packages (from matplotlib>=3.1->mplcursors) (0.11.0)
Requirement already satisfied: fonttools>=4.22.0 in c:\users\richarda\appdata\local\programs\python\python311\lib\site-packages (from matplotlib>=3.1->mplcursors) (4.39.3)
Requirement already satisfied: kiwisolver>=1.0.1 in c:\users\richarda\appdata\local\programs\python\python311\lib\site-packages (from matplotlib>=3.1->mplcursors) (1.4.4)
Requirement already satisfied: numpy>=1.20 in c:\users\richarda\appdata\local\programs\python\python311\lib\site-packages (from matplotlib>=3.1->mplcursors) (1.24.2)
Requirement already satisfied: packaging>=20.0 in c:\users\richarda\appdata\local\programs\python\python311\lib\site-packages (from matplotlib>=3.1->mplcursors) (23.0)
Requirement already satisfied: pillow>=6.2.0 in c:\users\richarda\appdata\local\programs\python\python311\lib\site-packages (from matplotlib>=3.1->mplcursors) (9.5.0)
Requirement already satisfied: pyparsing>=2.3.1 in c:\users\richarda\appdata\local\programs\python\python311\lib\site-packages (from matplotlib>=3.1->mplcursors) (3.0.9)
Requirement already satisfied: python-dateutil>=2.7 in c:\users\richarda\appdata\local\programs\python\python311\lib\site-packages (from matplotlib>=3.1->mplcursors) (2.8.2)
Requirement already satisfied: six>=1.5 in c:\users\richarda\appdata\local\programs\python\python311\lib\site-packages (from python-dateutil>=2.7->matplotlib>=3.1->mplcursors) (1.16.0)

[anntzer]

I meant the output of the failing install when you don't have setuptools_scm and mplcursors installed yet (you'll need to pip uninstall mplcursors setuptools_scm first).

[arnaudrichard]

pip.log

[anntzer]

Are you by any chance behind a proxy?

[arnaudrichard]

yep. And to make things worse a http proxy with authentication. I pass the "--proxy" option to pip and it worked for all other packages installed, including automatically their dependencies. (for example numpy, matplotlib, pandas, scipy) That's why I guess something can be improved in this one.

[anntzer]

Have you tried setting the http_proxy and https_proxy environment variables, as documented at https://pip.pypa.io/en/stable/user_guide/#using-a-proxy-server? This is what I usually do instead.

[arnaudrichard]

Nop, and I won't try because I already found a work-around with the installation of "setuptools_scm". I opened this ticket in case someone wants to improve the package.

[anntzer]

The alternate solution would be to use pyproject.toml to specify the dependency, but if using pyproject.toml you'd need to also require setuptools>=64 to support editable installs, which would then break support for Py3.6. Given that an alternate solution exists for proxy support, I'd rather also keep support for editable installs and for Py3.6 (unless you verify that setting the environment variable doesn't work for you). Thanks for pointing out the limitation, though.