fix(replay): Fix traces not always being attached to replays with errors

CHANGELOG.md

@@ -13,6 +13,7 @@
 - Fix duplicate error reporting on iOS with New Architecture ([#5532](https://github.com/getsentry/sentry-react-native/pull/5532))
 - Fix for missing `replay_id` from metrics ([#5483](https://github.com/getsentry/sentry-react-native/pull/5483))
 - Skip span ID check when standalone mode is enabled ([#5493](https://github.com/getsentry/sentry-react-native/pull/5493))
+- Fix traces not always being attached to replays with errors ([#5538](https://github.com/getsentry/sentry-react-native/pull/5538))
 
 ### Dependencies
 

packages/core/src/js/replay/mobilereplay.ts

@@ -216,6 +216,12 @@ export const mobileReplayIntegration = (initOptions: MobileReplayOptions = defau
       debug.log(
         `[Sentry] ${MOBILE_REPLAY_INTEGRATION_NAME} Captured recording replay ${replayId} for event ${event.event_id}.`,
       );
+      // Add replay_id to error event contexts to link replays to events/traces
+      event.contexts = event.contexts || {};
+      event.contexts.replay = {
+        ...event.contexts.replay,
+        replay_id: replayId,
+      };
     } else {
       // Check if there's an ongoing recording and update cache if found
       const recordingReplayId = NATIVE.getCurrentReplayId();
@@ -224,6 +230,12 @@ export const mobileReplayIntegration = (initOptions: MobileReplayOptions = defau
         debug.log(
           `[Sentry] ${MOBILE_REPLAY_INTEGRATION_NAME} assign already recording replay ${recordingReplayId} for event ${event.event_id}.`,
         );
+        // Add replay_id to error event contexts to link replays to events/traces
+        event.contexts = event.contexts || {};
+        event.contexts.replay = {
+          ...event.contexts.replay,
+          replay_id: recordingReplayId,
+        };
       } else {
         updateCachedReplayId(null);
         debug.log(`[Sentry] ${MOBILE_REPLAY_INTEGRATION_NAME} not sampled for event ${event.event_id}.`);

packages/core/test/replay/mobilereplay.test.ts

@@ -258,6 +258,25 @@ describe('Mobile Replay Integration', () => {
 
       expect(mockCaptureReplay).toHaveBeenCalled();
     });
+
+    it('should add replay context to error events when replay is captured', async () => {
+      const integration = mobileReplayIntegration();
+      const replayId = 'test-replay-id';
+      mockCaptureReplay.mockResolvedValue(replayId);
+
+      const event: Event = {
+        event_id: 'test-event-id',
+        exception: {
+          values: [{ type: 'Error', value: 'Test error' }],
+        },
+      };
+      const hint: EventHint = {};
+
+      if (integration.processEvent) {
+        const processedEvent = await integration.processEvent(event, hint);
+        expect(processedEvent.contexts?.replay?.replay_id).toBe(replayId);
+      }
+    });
   });
 
   describe('platform checks', () => {