step-04.md

A Guide to Writing an Elixir Analyzer Extension

Step 4: Adding unit tests for the new extension

1. Create a new file in /test/elixir_analyzer/test_suite/ called analyzer_extension_module_name_test.exs.

2. Do not use ExUnit.Case directly, but rather our custom ElixirAnalyzer.ExerciseTestCase. It takes the analyzer extension module as an option so that you don't need to repeat it with every test.

   use ElixirAnalyzer.ExerciseTestCase,
     exercise_test_module: ElixirAnalyzer.ExerciseTest.Example

3. Use the test_exercise_analysis macro to define test cases. It expects a test name, assertions about the analysis result comments, and a code snippet or list of code snippets in the do block. Refer to the macro's documentation for more details.

   # 04-example-analysis-test.exs
   defmodule ElixirAnalyzer.TestSuite.ExampleTest do
     use ElixirAnalyzer.ExerciseTestCase,
         exercise_test_module: ElixirAnalyzer.TestSuite.Example
   
     test_exercise_analysis "perfect solution",
       comments: [] do
       defmodule Example do
         @moduledoc """
         Greets the user
         """
         def hello(name) do
           "Hello, #{name}!"
         end
       end
     end
   end