add user delete_activities mix task

test/tasks/user_test.exs

@@ -248,4 +248,14 @@ defmodule Mix.Tasks.Pleroma.UserTest do
       assert message =~ "Generated"
     end
   end
+
+  describe "running delete_activities" do
+    test "activities are deleted" do
+      %{nickname: nickname} = insert(:user)
+
+      assert :ok == Mix.Tasks.Pleroma.User.run(["delete_activities", nickname])
+      assert_received {:mix_shell, :info, [message]}
+      assert message == "User #{nickname} statuses deleted."
+    end
+  end
 end

test/user_test.exs

@@ -792,6 +792,16 @@ defmodule Pleroma.UserTest do
     assert false == user.info.deactivated
   end
 
+  test ".delete_user_activities deletes all create activities" do
+    user = insert(:user)
+
+    {:ok, activity} = CommonAPI.post(user, %{"status" => "2hu"})
+    {:ok, _} = User.delete_user_activities(user)
+
+    # TODO: Remove favorites, repeats, delete activities.
+    refute Activity.get_by_id(activity.id)
+  end
+
   test ".delete deactivates a user, all follow relationships and all create activities" do
     user = insert(:user)
     followed = insert(:user)