ref: Use deque for breadcrumbs (#71)

* ref: Use deque for breadcrumbs

* fix: Python 2 compat

Author: untitaker

sentry_sdk/hub.py

@@ -206,7 +206,7 @@ def add_breadcrumb(self, crumb=None, hint=None, **kwargs):
         else:
             logger.info("before breadcrumb dropped breadcrumb (%s)", original_crumb)
         while len(scope._breadcrumbs) > client.options["max_breadcrumbs"]:
-            scope._breadcrumbs.pop(0)
+            scope._breadcrumbs.popleft()
 
     def push_scope(self, callback=None):
         """Pushes a new layer on the scope stack. Returns a context manager

sentry_sdk/scope.py

@@ -1,3 +1,6 @@
+from copy import copy
+from collections import deque
+
 from sentry_sdk.utils import logger, capture_internal_exceptions
 
 
@@ -84,7 +87,7 @@ def clear(self):
         self._contexts = {}
         self._extras = {}
 
-        self._breadcrumbs = []
+        self._breadcrumbs = deque()
 
     def add_event_processor(self, func):
         """"Register a scope local event processor on the scope.
@@ -170,7 +173,7 @@ def __copy__(self):
         rv._contexts = dict(self._contexts)
         rv._extras = dict(self._extras)
 
-        rv._breadcrumbs = list(self._breadcrumbs)
+        rv._breadcrumbs = copy(self._breadcrumbs)
         rv._event_processors = list(self._event_processors)
         rv._error_processors = list(self._error_processors)
 

tests/test_basics.py

@@ -141,18 +141,32 @@ def test_push_scope_null_client(sentry_init, capture_events):
     assert len(events) == 0
 
 
-def test_breadcrumbs_overflow(sentry_init, capture_events):
+def test_breadcrumbs(sentry_init, capture_events):
     sentry_init(max_breadcrumbs=10)
+    events = capture_events()
 
     for i in range(20):
         add_breadcrumb(
             category="auth", message="Authenticated user %s" % i, level="info"
         )
 
-    events = capture_events()
-
     capture_exception(ValueError())
-
     event, = events
 
     assert len(event["breadcrumbs"]) == 10
+    assert "user 10" in event["breadcrumbs"][0]["message"]
+    assert "user 19" in event["breadcrumbs"][-1]["message"]
+
+    del events[:]
+
+    for i in range(2):
+        add_breadcrumb(
+            category="auth", message="Authenticated user %s" % i, level="info"
+        )
+
+    with configure_scope() as scope:
+        scope.clear()
+
+    capture_exception(ValueError())
+    event, = events
+    assert len(event["breadcrumbs"]) == 0