test: avoid side effects from mutating environ

tests/test_api.py

@@ -23,7 +23,7 @@ def setUp(self):
         self.env_patcher.start()
 
     def tearDown(self):
-        del os.environ["AWS_REGION"]
+        self.env_patcher.stop()
 
     @patch("datadog_lambda.config.Config.fips_mode_enabled", True)
     @patch("botocore.session.Session.create_client")
@@ -172,7 +172,6 @@ def test_no_fips_for_standard_regions(self, mock_boto3_client):
         mock_client.get_secret_value.return_value = {"SecretString": "test-api-key"}
         mock_boto3_client.return_value = mock_client
 
-        os.environ.clear()
         os.environ["AWS_REGION"] = "us-west-2"
         os.environ["DD_API_KEY_SECRET_ARN"] = (
             "arn:aws:secretsmanager:us-west-2:1234567890:secret:key-name-123ABC"

tests/test_wrapper.py

@@ -113,6 +113,7 @@ def lambda_handler(event, context):
         self.mock_inject_correlation_ids.assert_called()
 
     def test_datadog_lambda_wrapper_flush_to_log(self):
+        self.addCleanup(os.environ.pop, "DD_FLUSH_TO_LOG", None)
         os.environ["DD_FLUSH_TO_LOG"] = "True"
 
         @wrapper.datadog_lambda_wrapper
@@ -124,8 +125,6 @@ def lambda_handler(event, context):
 
         self.mock_threadstats_flush_distributions.assert_not_called()
 
-        del os.environ["DD_FLUSH_TO_LOG"]
-
     def test_datadog_lambda_wrapper_flush_in_thread(self):
         # force ThreadStats to flush in thread
         import datadog_lambda.metric as metric_module
@@ -183,6 +182,7 @@ def lambda_handler(event, context):
 
     @patch("datadog_lambda.config.Config.trace_enabled", False)
     def test_datadog_lambda_wrapper_inject_correlation_ids(self):
+        self.addCleanup(os.environ.pop, "DD_LOGS_INJECTION", None)
         os.environ["DD_LOGS_INJECTION"] = "True"
 
         @wrapper.datadog_lambda_wrapper
@@ -194,8 +194,6 @@ def lambda_handler(event, context):
         self.mock_set_correlation_ids.assert_called()
         self.mock_inject_correlation_ids.assert_called()
 
-        del os.environ["DD_LOGS_INJECTION"]
-
     def test_invocations_metric(self):
         @wrapper.datadog_lambda_wrapper
         def lambda_handler(event, context):
@@ -484,6 +482,7 @@ def lambda_handler(event, context):
 
     def test_dd_requests_service_name_default(self):
         # TODO(astuyve) this is now set by CI, so we need to null it out for this case
+        self.addCleanup(os.environ.pop, "DD_SERVICE", None)
         os.environ["DD_SERVICE"] = "aws.lambda"
 
         @wrapper.datadog_lambda_wrapper
@@ -493,14 +492,14 @@ def lambda_handler(event, context):
         self.assertEqual(os.environ.get("DD_REQUESTS_SERVICE_NAME"), "aws.lambda")
 
     def test_dd_requests_service_name_set(self):
+        self.addCleanup(os.environ.pop, "DD_SERVICE", None)
         os.environ["DD_SERVICE"] = "myAwesomeService"
 
         @wrapper.datadog_lambda_wrapper
         def lambda_handler(event, context):
             pass
 
         self.assertEqual(os.environ.get("DD_REQUESTS_SERVICE_NAME"), "myAwesomeService")
-        del os.environ["DD_SERVICE"]
 
     @patch("datadog_lambda.config.Config.make_inferred_span", False)
     def test_encode_authorizer_span(self):
@@ -563,12 +562,13 @@ class TestLambdaWrapperWithTraceContext(unittest.TestCase):
         f"Root={xray_root};Parent={xray_parent};Sampled=1;Lineage=c6c5b1b9:0"
     )
 
-    @patch(
-        "os.environ",
+    @patch.dict(
+        os.environ,
         {
             "AWS_XRAY_DAEMON_ADDRESS": xray_daemon_envvar,
             "_X_AMZN_TRACE_ID": xray_trace_envvar,
         },
+        clear=True,
     )
     def test_event_bridge_sqs_payload(self):
         reset_xray_connection()
@@ -782,6 +782,7 @@ def lambda_handler(event, context):
             lambda_handler(self.api_gateway_request, get_mock_context())
 
     def test_no_blocking_appsec_disabled(self):
+        self.addCleanup(os.environ.pop, "DD_APPSEC_ENABLED", None)
         os.environ["DD_APPSEC_ENABLED"] = "false"
 
         importlib.reload(wrapper)