fix: Ensure SentrySDK.close resets everything on the main thread (#6907)

* fix: Ensure SentrySDK.close resets everything on the main thread

* Update changelog

* Use `dispatchSyncOnMainQueue` + update startTimestamp inside the block

Author: itaybre

CHANGELOG.md

@@ -1,5 +1,11 @@
 # Changelog
 
+## Unreleased
+
+### Fixes
+
+- fix: Ensure SentrySDK.close resets everything on the main thread (#6907)
+
 ## 9.0.0-rc.1
 
 ### Breaking Changes

Sources/Sentry/SentrySDKInternal.m

@@ -613,36 +613,39 @@ + (void)close
 {
     SENTRY_LOG_DEBUG(@"Starting to close SDK.");
 
+    [SentryDependencyContainer.sharedInstance.dispatchQueueWrapper dispatchSyncOnMainQueue:^{
+
 #if SENTRY_TARGET_PROFILING_SUPPORTED
-    [SentryContinuousProfiler stop];
+        [SentryContinuousProfiler stop];
 #endif // SENTRY_TARGET_PROFILING_SUPPORTED
 
-    startTimestamp = nil;
+        startTimestamp = nil;
 
-    SentryHubInternal *hub = SentrySDKInternal.currentHub;
-    [hub removeAllIntegrations];
+        SentryHubInternal *hub = SentrySDKInternal.currentHub;
+        [hub removeAllIntegrations];
 
-    SENTRY_LOG_DEBUG(@"Uninstalled all integrations.");
+        SENTRY_LOG_DEBUG(@"Uninstalled all integrations.");
 
 #if SENTRY_HAS_UIKIT
-    // force the AppStateManager to unsubscribe, see
-    // https://github.com/getsentry/sentry-cocoa/issues/2455
-    [[SentryDependencyContainer sharedInstance].appStateManager stopWithForce:YES];
+        // force the AppStateManager to unsubscribe, see
+        // https://github.com/getsentry/sentry-cocoa/issues/2455
+        [[SentryDependencyContainer sharedInstance].appStateManager stopWithForce:YES];
 #endif
 
-    [hub close];
-    [hub bindClient:nil];
+        [hub close];
+        [hub bindClient:nil];
 
-    [SentrySDKInternal setCurrentHub:nil];
+        [SentrySDKInternal setCurrentHub:nil];
 
-    [SentryDependencyContainer.sharedInstance.crashWrapper stopBinaryImageCache];
-    [SentryDependencyContainer.sharedInstance.binaryImageCache stop];
+        [SentryDependencyContainer.sharedInstance.crashWrapper stopBinaryImageCache];
+        [SentryDependencyContainer.sharedInstance.binaryImageCache stop];
 
 #if TARGET_OS_IOS && SENTRY_HAS_UIKIT
-    [SentryDependencyContainer.sharedInstance.uiDeviceWrapper stop];
+        [SentryDependencyContainer.sharedInstance.uiDeviceWrapper stop];
 #endif // TARGET_OS_IOS && SENTRY_HAS_UIKIT
 
-    [SentryDependencyContainer reset];
+        [SentryDependencyContainer reset];
+    }];
     SENTRY_LOG_DEBUG(@"SDK closed!");
 }
 

Tests/SentryTests/SentrySDKInternalTests.swift

@@ -667,6 +667,26 @@ class SentrySDKInternalTests: XCTestCase {
         XCTAssertEqual(flushTimeout, transport.flushInvocations.first ?? 0.0, accuracy: 0.2)
     }
 
+    func testClose_DispatchesOnMainThread() {
+        // Arrange
+        let dispatchQueueWrapper = TestSentryDispatchQueueWrapper()
+        SentryDependencyContainer.sharedInstance().dispatchQueueWrapper = dispatchQueueWrapper
+
+        SentrySDK.start { options in
+            options.dsn = SentrySDKInternalTests.dsnAsString
+            options.removeAllIntegrations()
+        }
+
+        // Reset the invocation count after start since start also uses the main thread dispatch
+        dispatchQueueWrapper.blockOnMainInvocations = Invocations<() -> Void>()
+
+        // Act
+        SentrySDK.close()
+
+        // Assert
+        XCTAssertEqual(1, dispatchQueueWrapper.blockOnMainInvocations.count, "Close should dispatch exactly once to main queue")
+    }
+
 #if os(iOS) || os(tvOS) || targetEnvironment(macCatalyst)
 
     func testSetAppStartMeasurementConcurrently() {