From 1da2129ea619272fd473a44269693797ada9d052 Mon Sep 17 00:00:00 2001
From: dongfuye <118151011+dongfuye@users.noreply.github.com>
Date: Sat, 14 Jan 2023 16:20:06 +0800
Subject: [PATCH] [#182][#181] Fix the crash when `:gc_interval` is not set
 (#183)

---
 lib/nebulex/adapters/local/generation.ex      |  7 +++++--
 .../adapters/local/generation_test.exs        | 20 +++++++++++++++++++
 2 files changed, 25 insertions(+), 2 deletions(-)

diff --git a/lib/nebulex/adapters/local/generation.ex b/lib/nebulex/adapters/local/generation.ex
index b2d629cf..1a7cf822 100644
--- a/lib/nebulex/adapters/local/generation.ex
+++ b/lib/nebulex/adapters/local/generation.ex
@@ -496,9 +496,12 @@ defmodule Nebulex.Adapters.Local.Generation do
     Metadata.put(meta_tab, :deprecated, older)
   end
 
-  defp start_timer(time, ref \\ nil, event \\ :heartbeat) do
-    _ = if ref, do: Process.cancel_timer(ref)
+  defp start_timer(time, ref \\ nil, event \\ :heartbeat)
+
+  defp start_timer(nil, _, _), do: nil
 
+  defp start_timer(time, ref, event) do
+    _ = if ref, do: Process.cancel_timer(ref)
     Process.send_after(self(), event, time)
   end
 
diff --git a/test/nebulex/adapters/local/generation_test.exs b/test/nebulex/adapters/local/generation_test.exs
index 16878d20..611563f1 100644
--- a/test/nebulex/adapters/local/generation_test.exs
+++ b/test/nebulex/adapters/local/generation_test.exs
@@ -307,6 +307,26 @@ defmodule Nebulex.Adapters.Local.GenerationTest do
     end
   end
 
+  describe "cleanup cover" do
+    test "cleanup when gc_interval not set" do
+      {:ok, _pid} =
+        LocalWithSizeLimit.start_link(
+          max_size: 3,
+          gc_cleanup_min_timeout: 1000,
+          gc_cleanup_max_timeout: 1500
+        )
+
+      # Put some entries to exceed the max size
+      _ = cache_put(LocalWithSizeLimit, 1..4)
+
+      # Wait the max cleanup timeout
+      :ok = Process.sleep(1600)
+
+      # assert not crashed
+      assert LocalWithSizeLimit.count_all() == 4
+    end
+  end
+
   ## Private Functions
 
   defp check_cache_size(cache) do