Update conda before enabling conda-forge in Appveyor

[martin-frbg]

Description fixes recent CI failure "InvalidVersionSpecError: Invalid version spec =2.7" (see also conda/conda issue 10618) Checklist N/A

[martin-frbg]

I don't know, but closing and reopening this PR (to rerun the CI) should tell

[weslleyspereira]

Same problem. Thanks for rerunning it.

[martin-frbg]

nope, seems to be a more recent problem. (the only reference I can find is from Oct 15, but only a githubmemory link with no accessible primary source)

[weslleyspereira]

Hi @martin-frbg. Do you have any update on this thread? The current script for Appveyor is not working.

[martin-frbg]

I had pretty much given up on this - no time and energy to debug conda on top of everything else. The originally proposed fix used to work for a few weeks around when I created the PR... The appveyor.yml in OpenBLAS does not have this problem, but the difference in base images may explain that.

[martin-frbg]

Hmm, looks like it primarily needs the updated miniconda that is already preinstalled alongside the one currently used. (Plus dropping the build cache - once, I guess - so that cmake forgets about the old compiler location). The remaining build failure now appears to be a genuine accuracy error in the tests.

[weslleyspereira]

Hmm, looks like it primarily needs the updated miniconda that is already preinstalled alongside the one currently used. (Plus dropping the build cache - once, I guess - so that cmake forgets about the old compiler location). The remaining build failure now appears to be a genuine accuracy error in the tests.

Great news!!

Should I remove the commented lines? Maybe it is a good idea to let those lines in case we need to test alternatives to work with future updates in conda.

[martin-frbg]

I guess we may want to keep the one commented line that disabled automatic updates of conda itself. The others are either options I moved into the remaining commands, or commands that did nothing to solve the problem. (And I notice that the title of this PR is outdated now as well)

[langou]

Thanks @martin-frbg for getting appveyor to work again!

[martin-frbg]

We'll probably need a follow-on to reenable the build cache once this is merged (and Appveyor has run once more)

[weslleyspereira]

We'll probably need a follow-on to reenable the build cache once this is merged (and Appveyor has run once more)

Ok! I will merge it now, and we watch how it behaves. Thanks!