How write test for an Elixir script file (Mix.install)

Questions / Help
1

Hi,
I would like to know how to write test for an Elixir script created using Mix.install, let say I have script.exs then what is the best way to write test for it?

Thank you in advance.

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2

not sure if this is the best way, but it should work =)

script.exs

defmodule Foo do def bar, do: :baz end

In the same dir put script_test.exs

Code.require_file("script.exs") ExUnit.start() defmodule FooTest do use ExUnit.Case test "bar/0 does :baz" do assert :baz == Foo.bar() end end

and run the test with

elixir script_test.exs
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3

@RudManusachi
It work like charm, thank you so much.
The following is a working example.

# demo.exs Mix.install([ {:bunt, "~> 0.2.0"} ]) defmodule Demo do def hello(name \\ "John") do ["Hello, ", :green, :bright, name] |> Bunt.ANSI.format |> IO.puts end end Demo.hello("Smahi") 
# demo_test.exs Code.require_file("demo.exs") ExUnit.start() defmodule DemoTest do use ExUnit.Case import ExUnit.CaptureIO test "hello/1" do output = capture_io(fn -> Demo.hello("Jahn") end) assert output == "Hello, \e[32m\e[1mJahn\e[0m\n" end end
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4

One important thing to keep in mind!

When we run Code.require_file/1 it compiles (executes) the file. So if we do some side effects, external service calls etc… those will be run each time we run tests :slightly_smiling_face:
Need to separate out the declaration and the usage.

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