Cleanup ExUnit test examples

Question

I have the following tests in phoenix app:

defmodule TattooBackend.Web.API.V1.PasswordControllerTest do
  use TattooBackend.Web.ConnCase, async: true
  use Bamboo.Test

  alias TattooBackend.Web.Endpoint
  alias TattooBackend.Accounts.Account
  alias TattooBackend.Repo
  alias Phoenix.Token
  alias Comeonin.Bcrypt
  import TattooBackend.AuthenticationRequiredTest

  test "without passwords", %{conn: conn} do
    account = insert(:account)
    token   = Token.sign(Endpoint, "account_id", account.id)

    conn =
      conn
      |> put_req_header("authorization", "#{token}")
      |> post(api_v1_password_path(conn, :create))

    assert json_response(conn, 422)
  end

  test "with wrong password confirmation", %{conn: conn} do
    account = insert(:account)
    token   = Token.sign(Endpoint, "account_id", account.id)
    params  = %{password: "new-password", password_confirmation: "password"}

    conn =
      conn
      |> put_req_header("authorization", "#{token}")
      |> post(api_v1_password_path(conn, :create, params))

    assert json_response(conn, 422)
  end
end

Those lines are repeated over tests:

account = insert(:account)
token   = Token.sign(Endpoint, "account_id", account.id)

Any idea how to make it more DRY?

Answer 1

If you want to execute those two lines in all tests, you can put the repetitive code in a setup callback and then use pattern matching to fetch those in each test:

defmodule TattooBackend.Web.API.V1.PasswordControllerTest do
  ...

  setup do
    account = insert(:account)
    token   = Token.sign(Endpoint, "account_id", account.id)
    [account: account, token: token]
  end

  test "without passwords", %{conn: conn, account: account, token: token} do
    conn =
      conn
      |> put_req_header("authorization", "#{token}")
      |> post(api_v1_password_path(conn, :create))

    assert json_response(conn, 422)
  end

  test "with wrong password confirmation", %{conn: conn, account: account, token: token} do
    params  = %{password: "new-password", password_confirmation: "password"}

    conn =
      conn
      |> put_req_header("authorization", "#{token}")
      |> post(api_v1_password_path(conn, :create, params))

    assert json_response(conn, 422)
  end
end

setup will execute its code before each test and then pass the account and token to each test.