put tests into functions

[joaquimg]

[matbesancon]

why particularly in functions? Are there some of these we would reuse?

[odow]

He means like this: https://github.com/jump-dev/MathOptInterface.jl/blob/master/test/functions.jl

The nested testset approach of Julia is pretty sub-optimal. These functions are much nicer to write, are more self-contained, and we can easily extend to new tools that run in parallel or on a subset of the tests (e.g., Pukeko.jl).