feat: add swoosh module

lib/igniter/libs/swoosh.ex

@@ -0,0 +1,24 @@
+defmodule Igniter.Libs.Swoosh do
+  @moduledoc "Codemods & utilities for working with Swoosh"
+
+  @doc "Lists all project modules that call `use Swoosh.Mailer`."
+  @spec list_mailers(Igniter.t()) :: {Igniter.t(), [module()]}
+  def list_mailers(igniter) do
+    Igniter.Project.Module.find_all_matching_modules(igniter, fn _mod, zipper ->
+      move_to_mailer_use(zipper) != :error
+    end)
+  end
+
+  @doc "Moves to the use statement in a module that matches `use Swoosh.Mailer`"
+  @spec move_to_mailer_use(Sourceror.Zipper.t()) ::
+          :error | {:ok, Sourceror.Zipper.t()}
+  def move_to_mailer_use(zipper) do
+    Igniter.Code.Function.move_to_function_call(zipper, :use, 2, fn zipper ->
+      Igniter.Code.Function.argument_equals?(
+        zipper,
+        0,
+        Swoosh.Mailer
+      )
+    end)
+  end
+end