Run example scripts on CI

[maxscheurer]

It would be good to run the small/fast example scripts on CI to ensure that these remain intact.

[maxscheurer]

What's the best way to run the examples btw? We somehow need to select the files according to available host programs, etc., and I don't have a clean way to do this in mind yet 😄

[mfherbst]

That's a good point. I guess pyscf and psi4 are easy to install and then we just run all scripts that contain an 'import pyscf' or 'import psi4' and which don't contain a flag indicating that they are too expensive. That should cover 90%.

[maxscheurer]

Psi4 is not easy to install outside the conda env, and even there, it can become difficult, as @loriab and I discovered last week due to mixture of c-f and defaults channel 😄

I saw that you've tagged your DFTK examples with some comment, I think that's a nice solution!

[mfherbst]

I saw that you've tagged your DFTK examples with some comment, I think that's a nice solution!

Yes it works ok, but have reached a limit there in the sense that the number of examples becomes large enough that we need to think about a clever way to save ci time there ... but we choose an opt-out solution.