Update Sink (VergeGroup#5)

Author: muukii

Package.swift

@@ -5,7 +5,7 @@ import PackageDescription
 
 let package = Package(
   name: "UserDefaultsSnapshotLib",
-  platforms: [.iOS(.v12)],
+  platforms: [.iOS(.v13), .macOS(.v10_15)],
   products: [
     // Products define the executables and libraries a package produces, and make them visible to other packages.
     .library(

Sources/UserDefaultsSnapshotLib/UserDefaultsPersistentStore.swift

@@ -55,32 +55,62 @@ open class UserDefaultsPersistentStore<Schema: UserDefaultsObject>: UserDefaults
     }
   }
 
-  public final func sinkSnapshot(_ sink: @escaping (UserDefaultsSnapshot<Schema>) -> Void) -> UserDefaultsPersistentStoreSinkCancellable {
+  public final func sinkSnapshot(_ sink: @escaping @Sendable (UserDefaultsSnapshot<Schema>) -> Void) -> UserDefaultsPersistentStoreSinkCancellable {
 
-    let token = UserDefaultsPersistentStoreSinkCancellable(owner: self)
-
-    initial: do {
+    // deliver initial
+    do {
       let snapshot = makeSnapshot()
 
       sink(
         snapshot
       )
     }
 
-    add { [weak self] in
+    return add { [weak self] in
       guard let self = self else { return }
 
       let snapshot = self.makeSnapshot()
 
-      DispatchQueue.main.async {
+      sink(
+        snapshot
+      )
+    }
+
+  }
+
+  public final func sinkSnapshotOnMain(_ sink: @escaping @MainActor (UserDefaultsSnapshot<Schema>) -> Void) -> UserDefaultsPersistentStoreSinkCancellable {
+
+    // deliver initial
+    do {
+      let snapshot = makeSnapshot()
+
+      if Thread.isMainThread {
+        MainActor.assumeIsolated {
+          sink(
+            snapshot
+          )
+        }
+      } else {
+        Task { @MainActor in
+          sink(
+            snapshot
+          )
+        }
+      }
+    }
+
+    return add { [weak self] in
+      guard let self = self else { return }
+
+      let snapshot = self.makeSnapshot()
+
+      Task { @MainActor in
         sink(
           snapshot
         )
       }
     }
 
-    return token
-
   }
 
 }

Sources/UserDefaultsSnapshotLib/UserDefaultsPersistentStoreBase.swift

@@ -16,7 +16,6 @@ open class UserDefaultsPersistentStoreBase: @unchecked Sendable {
 
   private let lock = NSLock()
 
-  @discardableResult
   public func add(_ eventReceiver: @escaping () -> Void) -> UserDefaultsPersistentStoreSinkCancellable {
     let token = UserDefaultsPersistentStoreSinkCancellable(owner: self)
     lock.lock()

Tests/UserDefaultsSnapshotLibTests/UserDefaultsBackingTests.swift

@@ -81,12 +81,21 @@ final class UserDefaultsBackingTests: XCTestCase {
     withExtendedLifetime(token) {}
   }
 
-  func testSinkUpdate() {
+  func testSinkUpdate() async {
+
+    actor Storage {
+      var results: [Int] = []
+      var snapshots: [UserDefaultsSnapshot<UserDefaultsBackingTests.MyDefaults>] = []
+
+      func perform(_ closure: @escaping (isolated Storage) -> ()) {
+        closure(self)
+      }
+    }
+
     let exp = expectation(description: "wait")
     exp.expectedFulfillmentCount = 3
 
-    var results: [Int] = []
-    var snapshots: [UserDefaultsSnapshot<UserDefaultsBackingTests.MyDefaults>] = []
+    let storage = Storage()
 
     let store = UserDefaultsPersistentStore<MyDefaults>(
       userDefaults: UserDefaults
@@ -96,9 +105,15 @@ final class UserDefaultsBackingTests: XCTestCase {
     // Start:
 
     let token = store.sinkSnapshot { snap in
-      results.append(snap.count)
-      snapshots.append(snap)
-      exp.fulfill()
+
+      Task {
+        await storage.perform {
+          $0.results.append(snap.count)
+          $0.snapshots.append(snap)
+        }
+        exp.fulfill()
+      }
+
     }
 
     store.write { d in
@@ -111,10 +126,15 @@ final class UserDefaultsBackingTests: XCTestCase {
 
     wait(for: [exp], timeout: 1)
 
-    XCTAssertEqual(results, [0, 1, 2])
+    let _results = await storage.results
+    let _snapshots = await storage.snapshots
 
-    XCTAssertEqual(snapshots.map { $0.count }, [0, 1, 2])
+    XCTAssertEqual(_results, [0, 1, 2])
+
+    XCTAssertEqual(_snapshots.map { $0.count }, [0, 1, 2])
 
     withExtendedLifetime(token) {}
   }
 }
+
+