Broken environment definition file

[Molkree]

Describe the bug
In #1549 compilers was removed from the env file.
As a result conda environment build fails on the pip stage: CondaEnvException: Pip failed. This is because pickle5 can't be built without gcc.

  unable to execute 'gcc': No such file or directory
  error: command 'gcc' failed with exit status 1
  ----------------------------------------
  ERROR: Failed building wheel for pickle5

Full console log.

To Reproduce
Just follow tardis installation steps up to conda env create -f tardis_env3.yml step.

Screenshots

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System

• OS:
  • GNU/Linux
  • macOS

Additional context
You can actually activate tardis environment even after this conda exception. But of course it will lack pip dependencies (though they are only used to build docs according to comment in the file?) and I'm not sure if conda does any steps after pip which could cause something else breaking.

I'm also using Python 3.8, so pickle5 is not even needed as it's a port of Python 3.8.3 pickle to Python 3.5-3.7. Maybe pickle5 ; python_version < '3.8' will work. We also don't need to redefine pickle on all Python versions, only < 3.8:

tardis/tardis/__init__.py

Lines 37 to 39 in e3a35bb

	import pickle5
	sys.modules["pickle"] = pickle5

P.S. Maybe add CI check to try and build environment (and install tardis in it?) when env file (and setup.py?) change. It's in the documentation-build workflow.

[epassaro]

I think this is not failing for us (or at the pipelines) because almost every Linux distro has gcc installed by default (or at some point) through the package manager.

I would try to move pickle5 to the conda dependencies (instead of pip section) and compilers should be pulled automatically @andrewfullard.

Remeber the reason of pickle5 is explained here #1535 and would be solved once we get rid of pyne (or pyne gets updated on macOS).

[epassaro]

Closed by #1566