From 523352c97e79d5a3c973541c89d0ec2295671206 Mon Sep 17 00:00:00 2001
From: Joakim Plate <elupus@ecce.se>
Date: Tue, 16 Jan 2024 13:38:47 +0100
Subject: [PATCH] Avoid keeping config dir in path (#107760)

---
 homeassistant/loader.py                          |  8 ++++++--
 tests/test_loader.py                             | 11 +++++++++++
 tests/testing_config/check_config_not_in_path.py |  1 +
 3 files changed, 18 insertions(+), 2 deletions(-)
 create mode 100644 tests/testing_config/check_config_not_in_path.py

diff --git a/homeassistant/loader.py b/homeassistant/loader.py
index 0a44ccb05c9..a4f1a862c45 100644
--- a/homeassistant/loader.py
+++ b/homeassistant/loader.py
@@ -1177,8 +1177,12 @@ def _async_mount_config_dir(hass: HomeAssistant) -> None:
 
     Async friendly but not a coroutine.
     """
-    if hass.config.config_dir not in sys.path:
-        sys.path.insert(0, hass.config.config_dir)
+
+    sys.path.insert(0, hass.config.config_dir)
+    with suppress(ImportError):
+        import custom_components  # pylint: disable=import-outside-toplevel  # noqa: F401
+    sys.path.remove(hass.config.config_dir)
+    sys.path_importer_cache.pop(hass.config.config_dir, None)
 
 
 def _lookup_path(hass: HomeAssistant) -> list[str]:
diff --git a/tests/test_loader.py b/tests/test_loader.py
index 7959ddb4684..501764bd022 100644
--- a/tests/test_loader.py
+++ b/tests/test_loader.py
@@ -873,3 +873,14 @@ async def test_async_suggest_report_issue(
         )
         == report_issue
     )
+
+
+async def test_config_folder_not_in_path(hass):
+    """Test that config folder is not in path."""
+
+    # Verify that we are unable to import this file from top level
+    with pytest.raises(ImportError):
+        import check_config_not_in_path  # noqa: F401
+
+    # Verify that we are able to load the file with absolute path
+    import tests.testing_config.check_config_not_in_path  # noqa: F401
diff --git a/tests/testing_config/check_config_not_in_path.py b/tests/testing_config/check_config_not_in_path.py
new file mode 100644
index 00000000000..312adec324e
--- /dev/null
+++ b/tests/testing_config/check_config_not_in_path.py
@@ -0,0 +1 @@
+"""File that should not be possible to import via direct import."""