/defmock

Easy mocking for Elixir

Primary LanguageElixir

defmock Build Status codebeat badge

Easy mock generation for Elixir.

Installation

Add defmock to your list of dependencies in mix.exs:

def deps do
  [
    {:defmock, github: "thau/defmock", tag: "v0.2.1"}
  ]
end

Usage

defmodule TestedModule do
  def function_with_external_api(external_api) do
    case external_api.call_me() do
      %{status_code: 200} -> :ok
      %{status_code: 404} -> :not_found
    end
  end

  def function_with_external_api_and_args(external_api) do
    case external_api.call_me(:foo, :bar, baz: 2, qux: 4) do
      %{status_code: 200} -> :ok
      %{status_code: 404} -> :not_found
    end
  end
end

defmodule Test do
  use ExUnit.Case
  import Defmock

  test "returns :ok if the external API returns status_code 200" do
    external_api = defmock(call_me: %{status_code: 200})
    assert TestedModule.function_with_external_api(external_api) == :ok
  end

  test "returns :not_found if the external API returns status_code 404" do
    external_api = defmock(call_me: %{status_code: 404})
    assert TestedModule.function_with_external_api(external_api) == :not_found
  end

  test "ensure that external API is being called" do
    external_api = defmock(call_me: %{status_code: 200})
    TestedModule.function_with_external_api(external_api)
    assert external_api.called?(:call_me)
  end

  test "ensure that external API is called with the right arguments" do
    external_api = defmock(call_me: %{status_code: 200})
    TestedModule.function_with_external_api_and_args(external_api)
    assert external_api.called_with?(:call_me, [:foo, :bar, baz: 2, qux: 4])
  end

  test "ensure that external API is called with some matching arguments" do
    external_api = defmock(call_me: %{status_code: 200})
    TestedModule.function_with_external_api_and_args(external_api)
    assert external_api.called_with_match?(:call_me, [:foo, :'_', [baz: :'_', qux: 4])
  end
end