From 5dd76966c383a4512ed5a60744cacbe5d6bdb5b1 Mon Sep 17 00:00:00 2001
From: "J. Nick Koston" <nick@koston.org>
Date: Fri, 4 Jul 2025 07:55:01 -0500
Subject: [PATCH] cover

---
 .../fixtures/defer_fifo_simple.yaml           | 36 +++++++++++++++++++
 tests/integration/test_defer_fifo_simple.py   | 29 +++++++++++++++
 2 files changed, 65 insertions(+)
 create mode 100644 tests/integration/fixtures/defer_fifo_simple.yaml
 create mode 100644 tests/integration/test_defer_fifo_simple.py

diff --git a/tests/integration/fixtures/defer_fifo_simple.yaml b/tests/integration/fixtures/defer_fifo_simple.yaml
new file mode 100644
index 0000000000..5cb675e77e
--- /dev/null
+++ b/tests/integration/fixtures/defer_fifo_simple.yaml
@@ -0,0 +1,36 @@
+esphome:
+  name: defer-fifo-simple
+  on_boot:
+    - lambda: |-
+        // Simple test: defer 10 items and verify they execute in order
+        static int execution_order = 0;
+        static bool test_passed = true;
+
+        for (int i = 0; i < 10; i++) {
+          int expected = i;
+          App.scheduler.set_timeout((Component*)nullptr, nullptr, 0, [expected]() {
+            ESP_LOGD("defer_test", "Deferred item %d executed, order %d", expected, execution_order);
+            if (execution_order != expected) {
+              ESP_LOGE("defer_test", "FIFO violation: expected %d but got execution order %d", expected, execution_order);
+              test_passed = false;
+            }
+            execution_order++;
+
+            if (execution_order == 10) {
+              if (test_passed) {
+                ESP_LOGI("defer_test", "✓ FIFO order test PASSED - all 10 items executed in correct order");
+              } else {
+                ESP_LOGE("defer_test", "✗ FIFO order test FAILED - items executed out of order");
+              }
+            }
+          });
+        }
+
+        ESP_LOGD("defer_test", "Deferred 10 items, waiting for execution...");
+
+host:
+
+logger:
+  level: DEBUG
+
+api:
diff --git a/tests/integration/test_defer_fifo_simple.py b/tests/integration/test_defer_fifo_simple.py
new file mode 100644
index 0000000000..7b3cf21737
--- /dev/null
+++ b/tests/integration/test_defer_fifo_simple.py
@@ -0,0 +1,29 @@
+"""Simple test that defer() maintains FIFO order."""
+
+import asyncio
+
+import pytest
+
+from .types import APIClientConnectedFactory, RunCompiledFunction
+
+
+@pytest.mark.asyncio
+async def test_defer_fifo_simple(
+    yaml_config: str,
+    run_compiled: RunCompiledFunction,
+    api_client_connected: APIClientConnectedFactory,
+) -> None:
+    """Test that defer() maintains FIFO order with a simple test."""
+
+    async with run_compiled(yaml_config), api_client_connected() as client:
+        # Just verify we can connect and the device is running
+        device_info = await client.device_info()
+        assert device_info is not None
+        assert device_info.name == "defer-fifo-simple"
+
+        # Give the test component time to run
+        await asyncio.sleep(5)
+
+        # The component will log results, we mainly want to ensure
+        # it doesn't crash and completes successfully
+        print("Defer FIFO simple test completed")