Update last_usage_registry.ex

lib/slack_silence/last_usage_registry.ex

@@ -1,8 +1,8 @@
 defmodule SlackQuiet.LastUsageRegistry do
  @moduledoc """
- We don't want to allow users to span `/quiet` in Slack, so we throttle them.
+ We don't want to allow users to spam `/quiet` in Slack, so we throttle them.
 
- We maintain an Agent with information about the last usage of the command
+ We maintain an agent with information about the last usage of the command
  for every user and we check if it has passed enough seconds since the last time.
  """
 
@@ -48,9 +48,17 @@ defmodule SlackQuiet.LastUsageRegistry do
  Agent.update(__MODULE__, &Map.put(&1, user_id, naive_datetime))
  end
 
- def flush do
- Agent.update(__MODULE__, fn _ -> %{} end)
- end
+ @doc """
+ Removes all entries in the registry.
+
+ ## Examples
+
+ iex> flush()
+ :ok
+
+ """
+ @spec flush :: :ok
+ def flush, do: Agent.update(__MODULE__, fn _ -> %{} end)
 
  @doc """
  Checks if the user is allowed to use the command right now.