Lack of `install_requires`

I know setup.py notes that not having install_requires is a deliberate decision, but is it possible to revisit that decision?

Right now pip install sphinx-gallery results in an incomplete install–I still need to manually install sphinx, matplotlib, and pillow to have a functional install. While sphinx and matplotlib are a given for my project, I need to now add pillow as a manual install step to my documentation CI builds–and it will break any time dependencies update in the future. Not to mention this becomes a much bigger headache should there be any version-specific needs in the future.

[larsoner]

Nowadays pip allows easy installation of everything, and I tend to find more harm than good done by omitting things from the requires list. I’d be fine adding matplotlib, sphinx, and pillow as dependencies (and adding a CI entry that things can actually work with this setup). Mayavi should be excluded, or added as an optional so people can do pip install sphinx_gallery[mayavi].

[anntzer]

If you do not want pip to ever mess your dependencies, you should just set the PIP_NO_DEPS environment variable, or similarly set ~/.config/pip/pip.conf appropriately (https://pip.pypa.io/en/stable/user_guide/#configuration). This way, you will have no problem whenever installing a package, regardless of whether it declares its requirements correctly or not.

I would thus still suggest that sphinx-gallery does declare install_requires properly, so that those who do want pip to install dependencies can benefit from it.