ecto-belongs-to-issue.exs

defmodule BelongsToReferenceKeyTest do
  use ExUnit.Case

  defmodule Foo do
    use Ecto.Model
  
    @primary_key {:foobar_id, :id, []}
  
    schema "foos" do
      belongs_to :bar, Bar
    end
  end

  defmodule Bar do
    use Ecto.Model
  
    schema "bars" do
      has_one :foo, Foo
    end
  end

  test "related_key should be equal to the related module's primary key" do
    assoc = Foo.__schema__(:association, :bar)
    assert assoc.related_key == List.first(assoc.related.__schema__(:primary_key))
  end
end