Programming Elixir ≥ 1.6

Write Some Basic Tests

At this point, I get a little nervous if I don’t have some tests. Fortunately, Elixir comes with a wonderful (and simple) testing framework called ExUnit.

Have a look at the file test/issues_test.exs.

project/0/issues/test/issues_test.exs

defmodule IssuesTest do
  use ExUnit.Case
  doctest Issues

  test "greets the world" do
    assert Issues.hello() == :world
  end
end

It acts as a template for all the test files you write. I just copy and paste the boilerplate into separate test files as I need them. So let’s write tests for our CLI module, putting those tests into the file test/cli_test.exs. (Test file names must end with _test.) We’ll test that the option parser successfully detects the -h and ...