From a341915da30eeeab15256bdaa787d198a956a466 Mon Sep 17 00:00:00 2001
From: DualFroz <me@dualfroz.com>
Date: Fri, 28 Aug 2026 20:23:00 +0200
Subject: [PATCH] test(persistence): add aof persistence tests

---
 test/excache/aof_test.exs | 70 +++++++++++++++++++++++++++++++++++++++
 1 file changed, 70 insertions(+)
 create mode 100644 test/excache/aof_test.exs

diff --git a/test/excache/aof_test.exs b/test/excache/aof_test.exs
new file mode 100644
index 0000000..9299254
--- /dev/null
+++ b/test/excache/aof_test.exs
@@ -0,0 +1,70 @@
+defmodule Excache.AofTest do
+  use Excache.Test.ServerCase, async: false
+
+  test "writes are appended live and replay reconstructs every data type", %{conn: conn} do
+    aof_path = Application.get_env(:excache, :aof_path)
+
+    assert {{:simple, "OK"}, conn} = Client.command(conn, ["SET", "durable", "v1"])
+    assert {1, conn} = Client.command(conn, ["LPUSH", "aof-list", "only"])
+    assert {1, conn} = Client.command(conn, ["HSET", "aof-hash", "field", "value"])
+    assert {1, conn} = Client.command(conn, ["SADD", "aof-set", "member"])
+    assert {1, conn} = Client.command(conn, ["ZADD", "aof-zset", "5", "ranked"])
+    assert {1, conn} = Client.command(conn, ["EXPIRE", "durable", "1000"])
+
+    Excache.Aof.flush()
+    Excache.Store.flushdb()
+
+    assert {nil, conn} = Client.command(conn, ["GET", "durable"])
+
+    Excache.Aof.replay(aof_path)
+
+    assert {"v1", conn} = Client.command(conn, ["GET", "durable"])
+    assert {["only"], conn} = Client.command(conn, ["LRANGE", "aof-list", "0", "-1"])
+    assert {"value", conn} = Client.command(conn, ["HGET", "aof-hash", "field"])
+    assert {["member"], conn} = Client.command(conn, ["SMEMBERS", "aof-set"])
+    assert {"5", conn} = Client.command(conn, ["ZSCORE", "aof-zset", "ranked"])
+    {ttl, _conn} = Client.command(conn, ["TTL", "durable"])
+    assert ttl > 0
+  end
+
+  test "a DEL logged after a SET is replayed in order and wins", %{conn: conn} do
+    aof_path = Application.get_env(:excache, :aof_path)
+
+    assert {{:simple, "OK"}, conn} = Client.command(conn, ["SET", "temp", "v"])
+    assert {1, conn} = Client.command(conn, ["DEL", "temp"])
+    assert {{:simple, "OK"}, conn} = Client.command(conn, ["SET", "temp", "final"])
+
+    Excache.Aof.flush()
+    Excache.Store.flushdb()
+    Excache.Aof.replay(aof_path)
+
+    assert {"final", _conn} = Client.command(conn, ["GET", "temp"])
+  end
+
+  test "read-only commands are not appended to the log", %{conn: conn} do
+    aof_path = Application.get_env(:excache, :aof_path)
+
+    assert {{:simple, "OK"}, conn} = Client.command(conn, ["SET", "readable", "v"])
+    assert {"v", _conn} = Client.command(conn, ["GET", "readable"])
+
+    Excache.Aof.flush()
+    {:ok, binary} = File.read(aof_path)
+
+    refute binary =~ "GET"
+    assert binary =~ "SET"
+  end
+
+  test "commands executed inside MULTI/EXEC are logged for replay", %{conn: conn} do
+    aof_path = Application.get_env(:excache, :aof_path)
+
+    assert {{:simple, "OK"}, conn} = Client.command(conn, ["MULTI"])
+    assert {{:simple, "QUEUED"}, conn} = Client.command(conn, ["SET", "txkey", "txvalue"])
+    assert {[{:simple, "OK"}], conn} = Client.command(conn, ["EXEC"])
+
+    Excache.Aof.flush()
+    Excache.Store.flushdb()
+    Excache.Aof.replay(aof_path)
+
+    assert {"txvalue", _conn} = Client.command(conn, ["GET", "txkey"])
+  end
+end