Proposal: Use the elixir requirement for more checks

[Kevin]

Hi,

as far as I understand, the elixir requirement currently only checks if the installed elixir version matches the requirement in the mix.exs file.

This would allow to use deps with a "higher" elixir requirement without failing or warning during resolution / compilation.

 

Would it be somehow feasible to check this during dependency resolution and warn the user? Something like "Your app requires Elixir 1.12, but :dep_xyz requires a minimum version of 1.13".

Another thing that would be great is to also check, if the `since` version of a function used in the project matches the elixir requirement in the mix file, which is probably a bit more complicated than the deps check. (e.g. "Your app requires Elixir 1.10, but Logger.warning/1 requires a minimum of 1.11").

What do you think? Would this be possible to implement and helpful for you?