ecto many to many query

contact_test.exs

# -*- c-basic-offset: 2; indent-tabs-mode: nil -*-
defmodule Score.ContactTest do
  use Score.TestCase

  @joe %{name: "joe", email: "joe@vipaar.com", sign_in_count: 0}
  @joe_changeset User.changeset(%User{}, :create, @joe)
  @bob %{name: "bob", email: "bob@vipaar.com", sign_in_count: 0}
  @bob_changeset User.changeset(%User{}, :create, @bob)

  setup do
    joe = Repo.insert!(@joe_changeset)
    bob = Repo.insert!(@bob_changeset)

    joe_bob = %{user1_id: joe.id, user2_id: bob.id}
    Contact.changeset(%Contact{}, :create, joe_bob)
    |> Repo.insert!
    {:ok, joe: joe, bob: bob}
  end

  test "finding a user's contacts", meta do
    query = Score.Query.User.contacts(meta.joe)
    contacts = Repo.all(query)
               |> Enum.map(&(&1.name))
    assert ^contacts = ["bob"]
  end
end

models-user.ex

defmodule Score.User do
  has_many :contacts, Score.Contact, foreign_key: :user1_id
  has_many :contact_connections, Score.Contact, foreign_key: :user2_id
end

query-user.ex

defmodule Score.Query.User do
  alias Score.Contact
  alias Score.User
  import Ecto.Query

  def contacts(user=%User{}) do
    from u in User,
      join: c in assoc(u, :contacts),
      inner_join: u1 in User, on: u1.id == c.user2_id,
      where: c.user1_id == u.id,
      select: u1
  end
end

Thanks for the gist!
I have one question though. Do you really need the where clause in the query-user (where: c.user1_id == u.id)? Isn't that statement already included in the
join: c in assoc(u, :contacts)