Refactor IDGenerator

Author: STREGA

Sources/GateEngine/ECS/Base/Component.swift

@@ -24,7 +24,7 @@ extension Component {
 }
 
 public struct ComponentID: Equatable, Hashable, Sendable {
-    nonisolated(unsafe) private static let idGenerator = IDGenerator<Int>(startValue: 0)
+    private static let idGenerator = IDGenerator<Int>(startValue: 0)
     @usableFromInline
     internal let value: Int
     public init() {

Sources/GateEngine/Helpers/IDGenerator.swift

@@ -5,46 +5,47 @@
  * http://stregasgate.com
  */
 
-#if canImport(Atomics)
-public import Atomics
-#elseif canImport(Foundation.NSLock)
-import class Foundation.NSLock
-#endif
+// A protocol to make sure all the possible variations have the same interface
+public protocol IDGeneratorProtocol: Sendable {
+    associatedtype T: BinaryInteger & Sendable
+    func generateID() -> T
+    init(startValue: T)
+}
 
 #if canImport(Atomics)
-nonisolated public final class IDGenerator<T: AtomicInteger & Sendable> {
+public import Atomics
+public struct IDGenerator<T: AtomicInteger & Sendable>: IDGeneratorProtocol {
     var value: ManagedAtomic<T>
-
     public init(startValue: T = 0) {
         value = ManagedAtomic<T>(startValue)
     }
 
     public func generateID() -> T {
-        return value.loadThenWrappingIncrement(ordering: .sequentiallyConsistent)
+        return value.loadThenWrappingIncrement(ordering: .relaxed)
     }
 }
 #elseif canImport(Foundation.NSLock)
-nonisolated public final class IDGenerator<T: BinaryInteger & Sendable> {
-    var value: T = 0
+import class Foundation.NSLock
+public final class IDGenerator<T: BinaryInteger & Sendable>: IDGeneratorProtocol {
+    // isolation is managed with a lock, so this is safe
+    nonisolated(unsafe) var value: T = 0
     let lock = NSLock()
 
     public init(startValue: T = 0) {
         self.value = startValue
     }
 
     public func generateID() -> T {
-        lock.lock()
-        let value = value
-        self.value += 1
-        defer {
-            lock.unlock()
+        return lock.withLock {
+            let value = value
+            self.value += 1
+            return value
         }
-        return value
     }
 }
 #else
-nonisolated public final class IDGenerator<T: BinaryInteger & Sendable> {
-    var value: T = 0
+public final class IDGenerator<T: BinaryInteger & Sendable>: IDGeneratorProtocol {
+    nonisolated(unsafe) var value: T = 0
 
     public init(startValue: T = 0) {
         self.value = startValue