Converts `SentryWatchdogTerminationLogic` and `SentryWatchdogTerminationTracker` to Swift #7118

itaybre · 2026-01-05T19:28:46Z

📜 Description

Changes:

Added SentryWatchdogTerminationLogic.swift with @objc support
Added SentryWatchdogTerminationTracker.swift with @objc support
Deleted old Objective-C implementations (.m and .h files)
Updated imports in Integration and other files to use Swift versions via
SentrySwift.h
Updated test data to reference Swift class properties

💡 Motivation and Context

These changes are needed to convert SentryWatchdogTerminationIntegration to Swift

💚 How did you test it?

📝 Checklist

You have to check all boxes before merging:

I added tests to verify the changes.
No new PII added or SDK only sends newly added PII if sendDefaultPII is enabled.
I updated the docs if needed.
I updated the wizard if needed.
Review from the native team if needed.
No breaking change or entry added to the changelog.
No breaking change for hybrid SDKs or communicated to hybrid SDKs.

No public changes, #skip-changelog

Closes #7127

@objc

…tionTracker to Swift Migrate the Logic and Tracker classes from Objective-C to Swift while keeping the Integration in Objective-C for now. The Swift classes are marked with @objc and @_spi(Private) to maintain compatibility with the existing Objective-C Integration. Changes: - Add SentryWatchdogTerminationLogic.swift with @objc support - Add SentryWatchdogTerminationTracker.swift with @objc support - Remove old Objective-C implementations - Update imports in Integration and other files to use Swift versions - Update test data to reference Swift class properties - Update bridging header to remove obsolete imports

codecov · 2026-01-05T19:48:43Z

Codecov Report

❌ Patch coverage is 91.45299% with 10 lines in your changes missing coverage. Please review.
✅ Project coverage is 84.739%. Comparing base (8440c54) to head (ff7fa11).
⚠️ Report is 3 commits behind head on main.
✅ All tests successful. No failed tests found.

Files with missing lines	Patch %	Lines
...gTerminations/SentryWatchdogTerminationLogic.swift	82.142%	10 Missing ⚠️

Additional details and impacted files

@@              Coverage Diff              @@
##              main     #7118       +/-   ##
=============================================
+ Coverage   84.710%   84.739%   +0.028%     
=============================================
  Files          459       459               
  Lines        27490     27515       +25     
  Branches     12117     12111        -6     
=============================================
+ Hits         23287     23316       +29     
+ Misses        4162      4157        -5     
- Partials        41        42        +1

Files with missing lines	Coverage Δ
Sources/Sentry/SentryClient.m	`97.435% <100.000%> (+0.009%)`	⬆️
Sources/Sentry/SentryCrashIntegration.m	`100.000% <ø> (ø)`
...rces/Sentry/SentryCrashIntegrationSessionHandler.m	`100.000% <ø> (ø)`
...try/SentryWatchdogTerminationTrackingIntegration.m	`89.655% <ø> (ø)`
...erminations/SentryWatchdogTerminationTracker.swift	`100.000% <100.000%> (ø)`
...gTerminations/SentryWatchdogTerminationLogic.swift	`82.142% <82.142%> (ø)`

... and 10 files with indirect coverage changes

Continue to review full report in Codecov by Sentry.

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github-actions · 2026-01-06T00:08:07Z

Performance metrics 🚀

	Plain	With Sentry	Diff
Startup time	1220.11 ms	1265.87 ms	45.76 ms
Size	24.14 KiB	1.03 MiB	1.01 MiB

Baseline results on branch: main

Startup times

Revision	Plain	With Sentry	Diff
`718c372`	1220.09 ms	1235.15 ms	15.06 ms
`7f2f69c`	1237.61 ms	1266.96 ms	29.35 ms
`80f98b4`	1229.95 ms	1252.68 ms	22.73 ms
`6c0b61e`	1194.21 ms	1218.74 ms	24.53 ms
`fa27d5b`	1195.50 ms	1218.19 ms	22.69 ms
`9080e6c`	1221.17 ms	1247.87 ms	26.71 ms
`af7a86c`	1220.82 ms	1243.36 ms	22.54 ms
`5cbd333`	1220.78 ms	1234.15 ms	13.36 ms
`22af3fc`	1220.16 ms	1250.25 ms	30.09 ms
`b13e93a`	1236.24 ms	1247.33 ms	11.08 ms

App size

Revision	Plain	With Sentry	Diff
`718c372`	23.75 KiB	920.65 KiB	896.90 KiB
`7f2f69c`	23.75 KiB	913.38 KiB	889.63 KiB
`80f98b4`	24.14 KiB	1.02 MiB	1017.65 KiB
`6c0b61e`	23.75 KiB	1.02 MiB	1019.10 KiB
`fa27d5b`	24.14 KiB	1.01 MiB	1015.38 KiB
`9080e6c`	23.75 KiB	926.80 KiB	903.05 KiB
`af7a86c`	23.74 KiB	926.65 KiB	902.90 KiB
`5cbd333`	23.74 KiB	969.66 KiB	945.92 KiB
`22af3fc`	23.75 KiB	1.00 MiB	1002.40 KiB
`b13e93a`	23.75 KiB	855.37 KiB	831.62 KiB

sentry · 2026-01-07T21:08:10Z

Sources/Swift/Integrations/WatchdogTerminations/SentryWatchdogTerminationLogic.swift

+@_implementationOnly import _SentryPrivate
+import Foundation
+
+#if (os(iOS) || os(tvOS) || os(visionOS)) && !SENTRY_NO_UIKIT


Bug: The Swift compilation guard for watchdog termination tracking excludes Mac Catalyst, causing a runtime crash when Objective-C code tries to instantiate the missing Swift classes on that platform.
_{Severity: CRITICAL | Confidence: High}

🔍 Detailed Analysis

The Swift classes SentryWatchdogTerminationLogic and SentryWatchdogTerminationTracker are conditionally compiled using a #if directive that excludes the Mac Catalyst target. However, existing Objective-C code, which is compiled for Mac Catalyst, attempts to instantiate these Swift classes. Because the classes are not included in the Mac Catalyst binary, this will cause a runtime crash when watchdog termination tracking is enabled on that platform. This is a regression introduced by the migration from Objective-C to Swift.

💡 Suggested Fix

Update the compilation guard in SentryWatchdogTerminationLogic.swift and SentryWatchdogTerminationTracker.swift to include the Mac Catalyst target. Change #if (os(iOS) || os(tvOS) || os(visionOS)) && !SENTRY_NO_UIKIT to #if (os(iOS) || os(tvOS) || os(visionOS) || targetEnvironment(macCatalyst)) && !SENTRY_NO_UIKIT.

🤖 Prompt for AI Agent

Review the code at the location below. A potential bug has been identified by an AI agent. Verify if this is a real issue. If it is, propose a fix; if not, explain why it's not valid. Location: Sources/Swift/Integrations/WatchdogTerminations/SentryWatchdogTerminationLogic.swift#L4 Potential issue: The Swift classes `SentryWatchdogTerminationLogic` and `SentryWatchdogTerminationTracker` are conditionally compiled using a `#if` directive that excludes the Mac Catalyst target. However, existing Objective-C code, which is compiled for Mac Catalyst, attempts to instantiate these Swift classes. Because the classes are not included in the Mac Catalyst binary, this will cause a runtime crash when watchdog termination tracking is enabled on that platform. This is a regression introduced by the migration from Objective-C to Swift.

_{Did we get this right? 👍 / 👎 to inform future reviews.}
_{Reference ID: 8304193}

This needs to be verified!

cursor · 2026-01-07T21:14:05Z

Sources/Swift/Integrations/WatchdogTerminations/SentryWatchdogTerminationLogic.swift

+           let previousVendorId = previousAppState.vendorId,
+           currentVendorId != previousVendorId {
+            return false
+        }


Vendor ID nil handling differs from original behavior

Medium Severity

The vendor ID check in the Swift conversion has different semantics than the original Objective-C code. In Objective-C, [nil isEqualToString:anything] and [anything isEqualToString:nil] both return NO, causing the original code to return NO (not a watchdog termination) whenever either vendorId was nil. The Swift if let pattern only returns false when BOTH vendor IDs are non-nil AND different. This means the Swift version will now continue checking and potentially report watchdog terminations in cases where one or both vendor IDs are nil, while the original would have rejected those cases.

This is valid feedback! The new if-condition doesn't check fo the cases where one of the two values is nil, but the other is set

philprime

Good progress, left some comments to discuss

philprime · 2026-01-08T10:59:13Z

Sources/Swift/Integrations/WatchdogTerminations/SentryWatchdogTerminationTracker.swift

+    @objc public static let SentryWatchdogTerminationExceptionType: String = "WatchdogTermination"
+    @objc public static let SentryWatchdogTerminationExceptionValue: String = "The OS watchdog terminated your app, possibly because it overused RAM."
+    @objc public static let SentryWatchdogTerminationMechanismType: String = "watchdog_termination"


l: These are already scoped to SentryWatchdogTerminationTracker so this leads to SentryWatchdogTerminationTracker.SentryWatchdogTerminationExceptionType which seems to be unnecessary

philprime · 2026-01-08T11:01:42Z

Sources/Swift/Integrations/WatchdogTerminations/SentryWatchdogTerminationTracker.swift

+    @objc public func start() {
+        appStateManager.start()
+
+        dispatchQueue.dispatchAsync {
+            guard self.watchdogTerminationLogic.isWatchdogTermination() else {
+                return
+            }
+
+            let event = Event(level: .fatal)
+
+            self.addBreadcrumbs(to: event)
+            self.addContext(to: event)
+            event.user = self.scopePersistentStore.readPreviousUserFromDisk()
+            event.dist = self.scopePersistentStore.readPreviousDistFromDisk()
+            event.environment = self.scopePersistentStore.readPreviousEnvironmentFromDisk()
+            event.tags = self.scopePersistentStore.readPreviousTagsFromDisk()
+            event.extra = self.scopePersistentStore.readPreviousExtrasFromDisk()
+            event.fingerprint = self.scopePersistentStore.readPreviousFingerprintFromDisk()
+            // Termination events always have fatal level, so we are not reading from disk
+
+            let exception = Exception(
+                value: SentryWatchdogTerminationTracker.SentryWatchdogTerminationExceptionValue,
+                type: SentryWatchdogTerminationTracker.SentryWatchdogTerminationExceptionType)
+            let mechanism = Mechanism(type: SentryWatchdogTerminationTracker.SentryWatchdogTerminationMechanismType)
+            mechanism.handled = false
+            exception.mechanism = mechanism
+            event.exceptions = [exception]
+
+            // We don't need to update the releaseName of the event to the previous app state as we
+            // assume it's not a watchdog termination when the releaseName changed between app
+            // starts.
+            SentrySDKInternal.captureFatalEvent(event)
+        }
+    }


m: We could reduce nesting and references to self:

Suggested change

@objc public func start() {

appStateManager.start()

dispatchQueue.dispatchAsync {

guard self.watchdogTerminationLogic.isWatchdogTermination() else {

return

}

let event = Event(level: .fatal)

self.addBreadcrumbs(to: event)

self.addContext(to: event)

event.user = self.scopePersistentStore.readPreviousUserFromDisk()

event.dist = self.scopePersistentStore.readPreviousDistFromDisk()

event.environment = self.scopePersistentStore.readPreviousEnvironmentFromDisk()

event.tags = self.scopePersistentStore.readPreviousTagsFromDisk()

event.extra = self.scopePersistentStore.readPreviousExtrasFromDisk()

event.fingerprint = self.scopePersistentStore.readPreviousFingerprintFromDisk()

// Termination events always have fatal level, so we are not reading from disk

let exception = Exception(

value: SentryWatchdogTerminationTracker.SentryWatchdogTerminationExceptionValue,

type: SentryWatchdogTerminationTracker.SentryWatchdogTerminationExceptionType)

let mechanism = Mechanism(type: SentryWatchdogTerminationTracker.SentryWatchdogTerminationMechanismType)

mechanism.handled = false

exception.mechanism = mechanism

event.exceptions = [exception]

// We don't need to update the releaseName of the event to the previous app state as we

// assume it's not a watchdog termination when the releaseName changed between app

// starts.

SentrySDKInternal.captureFatalEvent(event)

}

}

@objc public func start() {

appStateManager.start()

dispatchQueue.dispatchAsync {

self.captureStartEvent()

}

}

private func captureStartEvent() {

guard self.watchdogTerminationLogic.isWatchdogTermination() else {

return

}

let event = Event(level: .fatal)

addBreadcrumbs(to: event)

addContext(to: event)

event.user = scopePersistentStore.readPreviousUserFromDisk()

event.dist = scopePersistentStore.readPreviousDistFromDisk()

event.environment = scopePersistentStore.readPreviousEnvironmentFromDisk()

event.tags = scopePersistentStore.readPreviousTagsFromDisk()

event.extra = scopePersistentStore.readPreviousExtrasFromDisk()

event.fingerprint = scopePersistentStore.readPreviousFingerprintFromDisk()

// Termination events always have fatal level, so we are not reading from disk

let exception = Exception(

value: SentryWatchdogTerminationTracker.SentryWatchdogTerminationExceptionValue,

type: SentryWatchdogTerminationTracker.SentryWatchdogTerminationExceptionType)

let mechanism = Mechanism(type: SentryWatchdogTerminationTracker.SentryWatchdogTerminationMechanismType)

mechanism.handled = false

exception.mechanism = mechanism

event.exceptions = [exception]

// We don't need to update the releaseName of the event to the previous app state as we

// assume it's not a watchdog termination when the releaseName changed between app

// starts.

SentrySDKInternal.captureFatalEvent(event)

}

philprime · 2026-01-08T11:03:53Z

Sources/Swift/Integrations/WatchdogTerminations/SentryWatchdogTerminationLogic.swift

+@_implementationOnly import _SentryPrivate
+import Foundation
+
+#if (os(iOS) || os(tvOS) || os(visionOS)) && !SENTRY_NO_UIKIT


This needs to be verified!

philprime · 2026-01-08T11:06:00Z

Sources/Swift/Integrations/WatchdogTerminations/SentryWatchdogTerminationLogic.swift

+           let previousVendorId = previousAppState.vendorId,
+           currentVendorId != previousVendorId {
+            return false
+        }


This is valid feedback! The new if-condition doesn't check fo the cases where one of the two values is nil, but the other is set

philprime · 2026-01-08T11:07:40Z

Sources/Sentry/SentryClient.m


 - (BOOL)isWatchdogTermination:(SentryEvent *)event isFatalEvent:(BOOL)isFatalEvent
 {
+#if SENTRY_HAS_UIKIT


h: TBH I do not like that we pull the availability of UIKit in here. Why does the caller of the watchdog termination tracker need to know if it's available with or without UIKit?

philprime · 2026-01-08T11:08:39Z

Tests/SentryTests/Integrations/MetricKit/SentryMetricKitEventTests.swift

        XCTAssertTrue(createMetricKitEventWith(mechanismType: "mx_hang_diagnostic").isMetricKitEvent())
    }

+#if os(iOS) || os(tvOS) || os(visionOS) || targetEnvironment(macCatalyst)


m: Do not exclude the entire test, instead we should use a XCTSkip inside the test, so ideally the test suite is always the same, but we can see skips per platform

philprime · 2026-01-08T11:09:18Z

Tests/SentryTests/SentryClientTests.swift

    }

+#if os(iOS) || os(tvOS) || os(visionOS) || targetEnvironment(macCatalyst)
    func testCaptureOOMEvent_RemovesMutableInfoFromDeviceContext() throws {


m: Do not conditionally exclude the test from compilation, instead us the condition inside the test with an XCTSkip so we can see skipped tests per platform

itaybre added 2 commits January 5, 2026 15:58

Fix missing imports

a4fc2d3

Fix build on macOS

ff7fa11

itaybre added the ready-to-merge Use this label to trigger all PR workflows label Jan 5, 2026

itaybre marked this pull request as ready for review January 7, 2026 21:04

itaybre requested review from noahsmartin, philipphofmann and philprime as code owners January 7, 2026 21:04

github-actions bot mentioned this pull request Jan 7, 2026

Converts SentryWatchdogTerminationLogic and SentryWatchdogTerminationTracker to Swift #7127

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Converts SentryWatchdogTerminationLogic and SentryWatchdogTerminationTracker to Swift #7118

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itaybre commented Jan 5, 2026 • edited by github-actions bot Loading Uh oh! There was an error while loading. Please reload this page.

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📜 Description

💡 Motivation and Context

💚 How did you test it?

📝 Checklist

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Codecov Report

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github-actions bot commented Jan 6, 2026

Performance metrics 🚀

Baseline results on branch: main

Startup times

App size

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cursor bot Jan 7, 2026

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Vendor ID nil handling differs from original behavior

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Converts `SentryWatchdogTerminationLogic` and `SentryWatchdogTerminationTracker` to Swift #7118

Converts `SentryWatchdogTerminationLogic` and `SentryWatchdogTerminationTracker` to Swift #7118

itaybre commented Jan 5, 2026 •

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