Merge pull request #4394 from whatyouhide/mix-task-rerun

Add Mix.Task.rerun/1,2

lib/mix/lib/mix/task.ex

@@ -388,6 +388,18 @@ defmodule Mix.Task do
     end
   end
 
+  @doc """
+  Reruns `task` with the given arguments.
+
+  This function reruns the given task; to do that, it first re-enables the task
+  and then regularly runs it.
+  """
+  @spec rerun(task_name, [any]) :: any
+  def rerun(task, args \\ []) do
+    reenable(task)
+    run(task, args)
+  end
+
   @doc """
   Returns `true` if given module is a task.
   """

lib/mix/test/mix/task_test.exs

@@ -123,6 +123,21 @@ defmodule Mix.TaskTest do
     end
   end
 
+  test "rerun/1" do
+    assert Mix.Task.run("hello") == "Hello, World!"
+    assert Mix.Task.rerun("hello") == "Hello, World!"
+  end
+
+  test "rerun/1 for umbrella" do
+    in_fixture "umbrella_dep/deps/umbrella", fn ->
+      Mix.Project.in_project(:umbrella, ".", fn _ ->
+        assert [:ok, :ok] = Mix.Task.run "clean"
+        assert :noop      = Mix.Task.run "clean"
+        assert [:ok, :ok] = Mix.Task.rerun "clean"
+      end)
+    end
+  end
+
   test "get!" do
     assert Mix.Task.get!("hello") == Mix.Tasks.Hello