test: Make import-related tests stable (getsentry#3548)

BYK · web-flow · commit 2a2fab172e98 · 2024-09-23T15:26:32.000+02:00
The integrations not getting enabled when there are missing modules test was relying on certain packages not being installed in the environment and was causing issues when dev requirements was installed. This patch adds a context manager that simulates import errors for certain packages to make the test robust. It also enables the redis-related test by simulating a missing 'redis' package with the same context manager.
diff --git a/tests/test_basics.py b/tests/test_basics.py
@@ -29,6 +29,7 @@
 from sentry_sdk.integrations import (
     _AUTO_ENABLING_INTEGRATIONS,
     _DEFAULT_INTEGRATIONS,
+    DidNotEnable,
     Integration,
     setup_integrations,
 )
@@ -40,18 +41,6 @@
 from sentry_sdk.tracing_utils import has_tracing_enabled
 
 
-def _redis_installed():  # type: () -> bool
-    """
-    Determines whether Redis is installed.
-    """
-    try:
-        import redis  # noqa: F401
-    except ImportError:
-        return False
-
-    return True
-
-
 class NoOpIntegration(Integration):
     """
     A simple no-op integration for testing purposes.
@@ -90,20 +79,35 @@ def error_processor(event, exc_info):
     assert event["exception"]["values"][0]["value"] == "aha! whatever"
 
 
+class ModuleImportErrorSimulator:
+    def __init__(self, modules, error_cls=DidNotEnable):
+        self.modules = modules
+        self.error_cls = error_cls
+        for sys_module in list(sys.modules.keys()):
+            if any(sys_module.startswith(module) for module in modules):
+                del sys.modules[sys_module]
+
+    def find_spec(self, fullname, _path, _target=None):
+        if fullname in self.modules:
+            raise self.error_cls("Test import failure for %s" % fullname)
+
+    def __enter__(self):
+        # WARNING: We need to be first to avoid pytest messing with local imports
+        sys.meta_path.insert(0, self)
+
+    def __exit__(self, *_args):
+        sys.meta_path.remove(self)
+
+
 def test_auto_enabling_integrations_catches_import_error(sentry_init, caplog):
     caplog.set_level(logging.DEBUG)
-    redis_index = _AUTO_ENABLING_INTEGRATIONS.index(
-        "sentry_sdk.integrations.redis.RedisIntegration"
-    )  # noqa: N806
 
-    sentry_init(auto_enabling_integrations=True, debug=True)
+    with ModuleImportErrorSimulator(
+        [i.rsplit(".", 1)[0] for i in _AUTO_ENABLING_INTEGRATIONS]
+    ):
+        sentry_init(auto_enabling_integrations=True, debug=True)
 
     for import_string in _AUTO_ENABLING_INTEGRATIONS:
-        # Ignore redis in the test case, because it does not raise a DidNotEnable
-        # exception on import; rather, it raises the exception upon enabling.
-        if _AUTO_ENABLING_INTEGRATIONS[redis_index] == import_string:
-            continue
-
         assert any(
             record.message.startswith(
                 "Did not import default integration {}:".format(import_string)
@@ -883,9 +887,9 @@ def test_functions_to_trace_with_class(sentry_init, capture_events):
     assert event["spans"][1]["description"] == "tests.test_basics.WorldGreeter.greet"
 
 
-@pytest.mark.skipif(_redis_installed(), reason="skipping because redis is installed")
 def test_redis_disabled_when_not_installed(sentry_init):
-    sentry_init()
+    with ModuleImportErrorSimulator(["redis"], ImportError):
+        sentry_init()
 
     assert sentry_sdk.get_client().get_integration(RedisIntegration) is None
 
