I’m testing a library with multiple versions of Elixir on my CI. One of my dependencies is specified as a range. {:poison, ">= 3.1.0 and < 5.0.0", optional: true} Poison 4.0 is compatible with Elixir 1.6+ while Poison 3.1 is compatible with Elixir 1.3+. When my CI attempts to test in an Elixir 1.3…

Plug uses a different lock file to test with older dependencies: plug/mix.exs at main · elixir-plug/plug · GitHub defmodule Plug.MixProject do use Mix.Project # ... def project do [ # ... lockfile: lockfile(), # ... ] defp lockfile() do case System.get_env("C…

I do fear you have to do it like this: {:poison, cond do Version.match?(System.version, "~> 1.6") -> ">= 3.1.0 and < 5.0.0" Version.match?(System.version, "~> 1.3") -> ">= 3.1.0 and < 4.0.0" end, optional: true}

Are you able to build a different lockfile using mix or will I have to handle it manually?

I would update mix.exs and then run mix deps.get to generate the lock file: {:poison, ">= 3.1.0 and < 4.0.0", optional: true} Then I can rename the lock file, and revert changes on mix.lock and mix.exs.

Got it figured out! Thanks @NobbZ and @danschultzer for your help! Went with a combination of your two approaches. For reference: https://github.com/sticksnleaves/accent/blob/9f5011677827d98e2cedf976f4120132b719004c/mix.exs#L41-L50

Hmmm, I wonder if we could add this as tip for library maintainers. I’m not sure what the best place for that would be. Does anyone know?

This is where I’ve seen library guidelines before: https://hexdocs.pm/elixir/master/library-guidelines.html

Elixir Programming Language Forum

Only fetch deps compatible for a specific version of Elixir

Questions & Help Questions

anthonator August 31, 2018, 2:14pm 3

Any idea how hex.pm would handle reporting this?