fix(sdk-crash-detection): Reverse frame order (#49746)

The stack trace frames are ordered from caller to callee, or oldest to
youngest. Therefore, we must reverse the frame order when iterating
over the frames to detect an SDK crash.

This PR is based on #49593.

Co-authored-by: Joris Bayer <joris.bayer@sentry.io>
Co-authored-by: Arpad Borsos <arpad.borsos@sentry.io>

src/sentry/utils/sdk_crashes/cocoa_sdk_crash_detector.py

@@ -12,7 +12,10 @@ def is_sdk_crash(self, frames: Sequence[Mapping[str, Any]]) -> bool:
         if not frames:
             return False
 
-        for frame in frames:
+        # The frames are ordered from caller to callee, or oldest to youngest.
+        # The last frame is the one creating the exception.
+        # Therefore, we must iterate in reverse order.
+        for frame in reversed(frames):
             if self.is_sdk_frame(frame):
                 return True
 

tests/sentry/utils/sdk_crashes/test_fixture.py

@@ -25,7 +25,7 @@ def get_sentry_frame(function: str, in_app: bool = False) -> Mapping[str, Any]:
 
 
 def get_frames(function: str, sentry_frame_in_app: bool = False) -> Sequence[Mapping[str, Any]]:
-    return [
+    frames = [
         get_sentry_frame(function, sentry_frame_in_app),
         {
             "function": "LoginViewController.viewDidAppear",
@@ -73,6 +73,11 @@ def get_frames(function: str, sentry_frame_in_app: bool = False) -> Sequence[Map
         },
     ]
 
+    # The frames have to be ordered from caller to callee, or oldest to youngest.
+    # The last frame is the one creating the exception.
+    # As we usually look at stacktraces from youngest to oldest, we reverse the order.
+    return frames[::-1]
+
 
 def get_crash_event(handled=False, function="-[Sentry]", **kwargs) -> Sequence[Mapping[str, Any]]:
     return get_crash_event_with_frames(get_frames(function), handled=handled, **kwargs)

tests/sentry/utils/sdk_crashes/test_sdk_crash_detection.py

@@ -264,26 +264,26 @@ def test_frames_only_in_app_after_sentry_frame_not_reported(self, mock_sdk_crash
         self.execute_test(
             get_crash_event_with_frames(
                 [
-                    IN_APP_FRAME,
                     {
-                        "function": "__handleUncaughtException",
-                        "symbol": "__handleUncaughtException",
-                        "package": "CoreFoundation",
+                        "function": "std::__terminate",
+                        "symbol": "_ZSt11__terminatePFvvE",
+                        "package": "libc++abi.dylib",
                         "in_app": False,
                     },
+                    get_sentry_frame("sentrycrashdl_getBinaryImage"),
                     {
                         "function": "_objc_terminate",
                         "symbol": "_ZL15_objc_terminatev",
                         "package": "libobjc.A.dylib",
                         "in_app": False,
                     },
-                    get_sentry_frame("sentrycrashdl_getBinaryImage"),
                     {
-                        "function": "std::__terminate",
-                        "symbol": "_ZSt11__terminatePFvvE",
-                        "package": "libc++abi.dylib",
+                        "function": "__handleUncaughtException",
+                        "symbol": "__handleUncaughtException",
+                        "package": "CoreFoundation",
                         "in_app": False,
                     },
+                    IN_APP_FRAME,
                 ]
             ),
             False,