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Prevent deadlocks in SynchronizedUserDefaults #5858

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7c4c63e
inject lock
JZDesign Nov 24, 2025
f77a3c6
Add SynchronizedUserDefaults tests and fix Atomic deadlock
JZDesign Dec 8, 2025
3d6d9d6
Merge branch 'main' into jzdesign/re-entrant-lock-in-device-cache
JZDesign Dec 11, 2025
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4 changes: 4 additions & 0 deletions RevenueCat.xcodeproj/project.pbxproj
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Original file line number Diff line number Diff line change
Expand Up @@ -98,6 +98,7 @@
16E146B22E99FC7E0089B609 /* PurchaseResultComparator.swift in Sources */ = {isa = PBXBuildFile; fileRef = 16E146B12E99FC7E0089B609 /* PurchaseResultComparator.swift */; };
16E146B52E99FF640089B609 /* MockStoreTransaction.swift in Sources */ = {isa = PBXBuildFile; fileRef = 16E146B42E99FF640089B609 /* MockStoreTransaction.swift */; };
16E2B7F12EA01DFA00F04A7A /* SynchronizedLargeItemCacheTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = 16E2B7F02EA01DFA00F04A7A /* SynchronizedLargeItemCacheTests.swift */; };
16EE87CE2EE75B49002AC6FE /* SynchronizedUserDefaultsTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = 1639F7BF2EE7594B00652C13 /* SynchronizedUserDefaultsTests.swift */; };
16F376262E93F1E300ADF649 /* LargeItemCacheTypeTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = 16F376252E93F1E300ADF649 /* LargeItemCacheTypeTests.swift */; };
1D20E1D62EBCF80E00ABE4CD /* HTTPRequestTimeoutManager.swift in Sources */ = {isa = PBXBuildFile; fileRef = 1D20E1D52EBCF80E00ABE4CD /* HTTPRequestTimeoutManager.swift */; };
1D20E1D82EBCF82900ABE4CD /* HTTPRequestTimeoutManager.swift in Sources */ = {isa = PBXBuildFile; fileRef = 1D20E1D72EBCF82900ABE4CD /* HTTPRequestTimeoutManager.swift */; };
Expand Down Expand Up @@ -1553,6 +1554,7 @@
1622D3FA2E900DE000C20E3C /* ChecksumTests.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = ChecksumTests.swift; sourceTree = "<group>"; };
1622D3FC2E900F8200C20E3C /* Checksum.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = Checksum.swift; sourceTree = "<group>"; };
1622D40D2E90189F00C20E3C /* URLWithValidation.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = URLWithValidation.swift; sourceTree = "<group>"; };
1639F7BF2EE7594B00652C13 /* SynchronizedUserDefaultsTests.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = SynchronizedUserDefaultsTests.swift; sourceTree = "<group>"; };
164681C82E6B577600854AA5 /* VideoComponentView.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = VideoComponentView.swift; sourceTree = "<group>"; };
164681C92E6B577600854AA5 /* VideoComponentViewModel.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = VideoComponentViewModel.swift; sourceTree = "<group>"; };
164681CA2E6B577600854AA5 /* VideoPlayerView.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = VideoPlayerView.swift; sourceTree = "<group>"; };
Expand Down Expand Up @@ -4541,6 +4543,7 @@
37E35AE0CDC4C2AA8260FB58 /* Caching */ = {
isa = PBXGroup;
children = (
1639F7BF2EE7594B00652C13 /* SynchronizedUserDefaultsTests.swift */,
16E2B7F02EA01DFA00F04A7A /* SynchronizedLargeItemCacheTests.swift */,
16F376252E93F1E300ADF649 /* LargeItemCacheTypeTests.swift */,
16BCA36F2E4D9BA700B39E7F /* FileRepositoryTests.swift */,
Expand Down Expand Up @@ -7417,6 +7420,7 @@
351B51A526D450BC00BD2BD7 /* DateExtensionsTests.swift in Sources */,
35C05DC02BC84F5800109308 /* DiagnosticsSynchronizerTests.swift in Sources */,
B390F5BA271DDC7400B64D65 /* PurchasesDeprecation.swift in Sources */,
16EE87CE2EE75B49002AC6FE /* SynchronizedUserDefaultsTests.swift in Sources */,
57FDAABE28493A29009A48F1 /* SandboxEnvironmentDetectorTests.swift in Sources */,
57BA943128330ACA00CD5FC5 /* ConfigurationTests.swift in Sources */,
16BCA37A2E4D9C0400B39E7F /* MockSimpleNetworkService.swift in Sources */,
Expand Down
2 changes: 1 addition & 1 deletion Sources/Identity/CustomerInfoManager.swift
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Original file line number Diff line number Diff line change
Expand Up @@ -49,7 +49,7 @@ class CustomerInfoManager {
self.systemInfo = systemInfo
self.dateProvider = dateProvider

self.data = .init(.init(deviceCache: deviceCache))
self.data = .init(.init(deviceCache: deviceCache), lock: .init(.recursive))
}

@available(iOS 15.0, macOS 12.0, tvOS 15.0, watchOS 8.0, *)
Expand Down
11 changes: 8 additions & 3 deletions Sources/Misc/Concurrency/Atomic.swift
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Expand Up @@ -17,7 +17,7 @@ import Foundation
* A generic object that performs all write and read operations atomically.
* Use it to prevent data races when accessing an object.
*
* - Important: The closures aren't re-entrant.
* - Important: The closures aren't re-entrant unless specified during construction.
* In other words, `Atomic` instances cannot be used from within the `modify` and `withValue` closures
*
* Usage:
Expand Down Expand Up @@ -56,9 +56,9 @@ internal final class Atomic<T> {
set { modify { $0 = newValue } }
}

init(_ value: T) {
init(_ value: T, lock: Lock = Lock()) {
self._value = value
self.lock = Lock()
self.lock = lock
}

@discardableResult
Expand All @@ -78,6 +78,11 @@ internal final class Atomic<T> {

@discardableResult
func withValue<Result>(_ action: (T) throws -> Result) rethrows -> Result {
if Thread.isMainThread {
// If we're already on the main thread, execute directly to avoid deadlock.
return try action(_value)
}

return try lock.perform {
try action(_value)
}
Expand Down
2 changes: 1 addition & 1 deletion Sources/Misc/Concurrency/SynchronizedUserDefaults.swift
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Original file line number Diff line number Diff line change
Expand Up @@ -21,7 +21,7 @@ internal final class SynchronizedUserDefaults {
private let atomic: Atomic<UserDefaults>

init(userDefaults: UserDefaults) {
self.atomic = .init(userDefaults)
self.atomic = .init(userDefaults, lock: .init(.recursive))
}

func read<T>(_ action: (UserDefaults) throws -> T) rethrows -> T {
Expand Down
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