fix: Linking ongoing trace to crash event (#4393)

Fix linking a crash event to an ongoing trace by skipping setting the
trace context in Scope.applyToEvent for crash events.

Fixes GH-4375

CHANGELOG.md

@@ -17,6 +17,7 @@
 ### Fixes
 
 - Fix the versioning to support app release with Beta versions (#4368)
+- Linking ongoing trace to crash event (#4393)
 
 ## 8.37.0-beta.1
 

Sources/Sentry/SentryScope.m

@@ -2,7 +2,7 @@
 #import "SentryAttachment+Private.h"
 #import "SentryBreadcrumb.h"
 #import "SentryEnvelopeItemType.h"
-#import "SentryEvent.h"
+#import "SentryEvent+Private.h"
 #import "SentryGlobalEventProcessor.h"
 #import "SentryLevelMapper.h"
 #import "SentryLog.h"
@@ -564,6 +564,13 @@ - (SentryEvent *__nullable)applyToEvent:(SentryEvent *)event
         [SentryDictionary mergeEntriesFromDictionary:event.context intoDictionary:newContext];
     }
 
+    // Don't add the trace context of a current trace to a crash event because crash events are from
+    // a previous run.
+    if (event.isCrashEvent) {
+        event.context = newContext;
+        return event;
+    }
+
     if (self.span != nil) {
         id<SentrySpan> span;
         @synchronized(_spanLock) {

Tests/SentryTests/SentryScopeSwiftTests.swift

@@ -225,6 +225,17 @@ class SentryScopeSwiftTests: XCTestCase {
         XCTAssertEqual(trace?["span_id"] as? String, fixture.transaction.spanId.sentrySpanIdString)
     }
 
+    func testApplyToEvent_ScopeWithSpan_NotAppliedToCrashEvent() {
+        let scope = fixture.scope
+        scope.span = fixture.transaction
+        let event = fixture.event
+        event.isCrashEvent = true
+
+        let actual = scope.applyTo(event: event, maxBreadcrumbs: 10)
+        XCTAssertNil(fixture.event.context?["trace"])
+        XCTAssertNil(actual?.transaction)
+    }
+
     func testApplyToEvent_EventWithDist() {
         let event = fixture.event
         event.dist = "myDist"