up tp Chapter 2 - Compile-time hooks

Author: shmink

module-extension/.iex.exs

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+c("module_extension.exs")

module-extension/accumulated_module_attributes.exs

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+defmodule Assertion do
+  defmacro __using__(_options) do
+    quote do
+      import unquote(__MODULE__)
+      Module.register_attribute(__MODULE__, :tests, accumulate: true)
+
+      def run do
+        IO.puts("Running the tests (#{inspect(@tests)}")
+      end
+    end
+  end
+
+  defmacro test(description, do: test_block) do
+    test_func = String.to_atom(descriptions)
+
+    quote do
+      @tests {unquote(test_func), unquote(description)}
+      def unquote(test_func)(), do: unquote(test_block)
+    end
+  end
+end

module-extension/module_extension.exs

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+defmodule Assertion do
+  # ...
+  defmacro extend(options \\ []) do
+    quote do
+      import unquote(__MODULE__)
+
+      def run do
+        IO.puts("Running the tests...")
+      end
+    end
+  end
+
+  # ...
+end
+
+defmodule MathTest do
+  use Assertion
+end