function_exported? is not as reliable as __info__(:functions)

[SkipMike]

I have some ecto embedded schemas that seems just like structs in all cases except when Maptu calls function_exported?(DB.SQL.Schema.Cart.Loyalty, :__struct__, 0) which returns false. After I instantiate a struct with %DB.SQL.Schema.Cart.Loyalty{} then function_exported?(DB.SQL.Schema.Cart.Loyalty, :__struct__, 0) returns true. However, DB.SQL.Schema.Cart.Loyalty.module_info(:exports) always returns an up to date list of functions.

https://github.com/elixir-lang/elixir/blob/v1.7.3/lib/elixir/lib/kernel.ex#L3245 After reading the documentation for function_exported? It's clear that it doesn't load the code, if it's not already loaded. This makes sense, because it's only happening in my test environment. In any case, I think it would be easier to use Maptu if we can make the change to use module_info or __info__ instead of function_exported?. I'm happy to make a PR, if that would help.

[SkipMike]

@lexmag Is there something I can do to push this forward? I'd love to get this fix into production.