This post is hopefully for clarification with respect to “mocks” and application configuration.
With respect to mocking as described by José in Mocks and Explicit Contracts we leverage
Application.get_env(:my_app, :some_key) to provide the correct resource by adding config information to our config files, e.g. dev.exs, prod.exs, test.exs.
This is great, but when your project (proj_a) is a included as a dependency in another project (proj_b) then by default
Application.get_env(:proj_a, :some_key) will return nil and code in proj_a that depends on the resource provided by
Application.get_env(:proj_a, :some_key) will error. This forum post expands on access to config keys in a package.
We can fix this by adding the “correct” config information for proj_a in the config files of proj_b.
What I am wondering is if my interpretation is correct or am I missing something?
In particular I ran into this because I was using doing dev on my Macbook for something that is Linux file system specific. As a result I created a
mock and a mac_dev.exs file to allow me to do my dev on my Macbook while having a mock to provided the expected behavior of the code running on a Linux file system.
That code is fine and works, but when I include it as a dependency for another application and continue working on it the “proj_a” code will break if I do not define the correct proj_a config settings in “proj_b”.
That is fine, I just want to make sure I am doing things the “right” way and my understanding of how things work are correct.