tech(Observable) Remove observable object (#74)

.editorconfig

@@ -0,0 +1,10 @@
+root = true
+
+[*]
+end_of_line = lf
+trim_trailing_whitespace = true
+
+# 4 space indentation
+[*.swift]
+indent_style = space
+indent_size = 4

Sources/CohesionKit/EntityStore.swift

@@ -254,7 +254,7 @@ extension EntityStore {
     @discardableResult
     public func update<T: Identifiable>(_ type: T.Type, id: T.ID, modifiedAt: Stamp? = nil, update: Update<T>) -> Bool {
         transaction {
-            guard var entity = storage[T.self, id: id]?.ref.value else {
+            guard var entity = storage[T.self, id: id]?.value else {
                 return false
             }
 
@@ -275,7 +275,7 @@ extension EntityStore {
     @discardableResult
     public func update<T: Aggregate>(_ type: T.Type, id: T.ID, modifiedAt: Stamp? = nil, _ update: Update<T>) -> Bool {
         transaction {
-            guard var entity = storage[T.self, id: id]?.ref.value else {
+            guard var entity = storage[T.self, id: id]?.value else {
                 return false
             }
 
@@ -294,7 +294,7 @@ extension EntityStore {
     @discardableResult
     public func update<T: Identifiable>(named: AliasKey<T>, modifiedAt: Stamp? = nil, update: Update<T>) -> Bool {
         transaction {
-            guard let aliasNode = refAliases[named], var content = aliasNode.ref.value.content else {
+            guard let aliasNode = refAliases[named], var content = aliasNode.value.content else {
                 return false
             }
 
@@ -313,7 +313,7 @@ extension EntityStore {
     @discardableResult
     public func update<T: Aggregate>(named: AliasKey<T>, modifiedAt: Stamp? = nil, update: Update<T>) -> Bool {
         transaction {
-            guard let aliasNode = refAliases[named], var content = aliasNode.ref.value.content else {
+            guard let aliasNode = refAliases[named], var content = aliasNode.value.content else {
                 return false
             }
 
@@ -333,7 +333,7 @@ extension EntityStore {
     public func update<C: Collection>(named: AliasKey<C>, modifiedAt: Stamp? = nil, update: Update<C>)
     -> Bool where C.Element: Identifiable {
         transaction {
-            guard let aliasNode = refAliases[named], var content = aliasNode.ref.value.content else {
+            guard let aliasNode = refAliases[named], var content = aliasNode.value.content else {
                 return false
             }
 
@@ -353,7 +353,7 @@ extension EntityStore {
     public func update<C: Collection>(named: AliasKey<C>, modifiedAt: Stamp? = nil, update: Update<C>)
     -> Bool where C.Element: Aggregate {
         transaction {
-            guard let aliasNode = refAliases[named], var content = aliasNode.ref.value.content else {
+            guard let aliasNode = refAliases[named], var content = aliasNode.value.content else {
                 return false
             }
 

Sources/CohesionKit/Observer/EntityObserver.swift

@@ -9,22 +9,22 @@ public struct EntityObserver<T> {
     let createObserver: (@escaping OnChange) -> Subscription
 
     init(node: EntityNode<T>, registry: ObserverRegistry) {
-        self.value = node.ref.value
+        self.value = node.value
         self.createObserver = { onChange in
             registry.addObserver(node: node, initial: true, onChange: onChange)
         }
     }
 
     init<Element>(nodes: [EntityNode<Element>], registry: ObserverRegistry) where T == [Element] {
-        self.value = nodes.map(\.ref.value)
+        self.value = nodes.map(\.value)
         self.createObserver = { onChange in
             registry.addObserver(nodes: nodes, initial: true, onChange: onChange)
         }
     }
 
     init<Wrapped>(alias node: EntityNode<AliasContainer<Wrapped>>, registry: ObserverRegistry)
     where T == Optional<Wrapped> {
-        self.init(value: node.ref.value.content) { onChange in
+        self.init(value: node.value.content) { onChange in
             registry.addObserver(node: node, initial: true, onChange: { container in
                 onChange(container.content)
             })

Sources/CohesionKit/Observer/ObserverRegistry.swift

@@ -36,15 +36,15 @@ class ObserverRegistry {
     /// register an observer to observe changes on an entity node. Everytime `ObserverRegistry` is notified about changes
     /// to this node `onChange` will be called.
     func addObserver<T>(node: EntityNode<T>, key: ObjectKey, initial: Bool = false, onChange: @escaping (T) -> Void) -> Subscription {
-        let handler = Handler { onChange($0.ref.value) }
+        let handler = Handler { onChange($0.value) }
 
         if initial {
           if queue == DispatchQueue.main && Thread.isMainThread {
-            onChange(node.ref.value)
+            onChange(node.value)
           }
           else {
             queue.sync {
-              onChange(node.ref.value)
+              onChange(node.value)
             }
           }
         }
@@ -57,16 +57,16 @@ class ObserverRegistry {
     func addObserver<T>(nodes: [EntityNode<T>], initial: Bool = false, onChange: @escaping ([T]) -> Void) -> Subscription {
         let handler = Handler { (_: EntityNode<T>) in
             // use last value from nodes
-            onChange(nodes.map(\.ref.value))
+            onChange(nodes.map(\.value))
         }
 
         if initial {
           if queue == DispatchQueue.main && Thread.isMainThread {
-            onChange(nodes.map(\.ref.value))
+            onChange(nodes.map(\.value))
           }
           else {
             queue.sync {
-              onChange(nodes.map(\.ref.value))
+              onChange(nodes.map(\.value))
             }
           }
         }

Sources/CohesionKit/Observer/Subscription.swift

@@ -0,0 +1,21 @@
+import Foundation
+
+public class Subscription {
+    public let unsubscribe: () -> Void
+
+    init(unsubscribe: @escaping () -> Void) {
+        var unsubscribed = false
+
+        self.unsubscribe = {
+            if !unsubscribed {
+                unsubscribe()
+            }
+
+            unsubscribed = true
+        }
+    }
+
+    deinit {
+        unsubscribe()
+    }
+}

Sources/CohesionKit/Storage/EntityNode.swift

@@ -24,8 +24,7 @@ struct EntityMetadata {
 protocol AnyEntityNode: AnyObject {
     associatedtype Value
 
-    var ref: Observable<Value> { get }
-    var value: Any { get }
+    var value: Value { get }
     var metadata: EntityMetadata { get }
     var storageKey: String { get }
 
@@ -47,34 +46,28 @@ class EntityNode<T>: AnyEntityNode {
         let node: any AnyEntityNode
     }
 
-    var value: Any { ref.value }
+    private(set) var value: Value
 
     var metadata = EntityMetadata()
     // FIXME: to delete, it's "just" to have a strong ref and avoid nodes to be deleted. Need a better memory management
     private var childrenNodes: [any AnyEntityNode] = []
 
     var applyChildrenChanges = true
-    /// An observable entity reference
-    let ref: Observable<T>
 
     let storageKey: String
 
-    /// last time the ref.value was changed. Any subsequent change must have a higher value to be applied
+    /// last time `value` was changed. Any subsequent change must have a higher value to be applied
     /// if nil ref has no stamp and any change will be accepted
     private var modifiedAt: Stamp?
     /// entity children
     private(set) var children: [PartialKeyPath<T>: SubscribedChild] = [:]
 
-    init(ref: Observable<T>, key: String, modifiedAt: Stamp?) {
-        self.ref = ref
+    init(_ entity: T, key: String, modifiedAt: Stamp?) {
+        self.value = entity
         self.modifiedAt = modifiedAt
         self.storageKey = key
     }
 
-    convenience init(_ entity: T, key: String, modifiedAt: Stamp?) {
-        self.init(ref: Observable(value: entity), key: key, modifiedAt: modifiedAt)
-    }
-
     convenience init(_ entity: T, modifiedAt: Stamp?) where T: Identifiable {
         let key = "\(T.self)-\(entity.id)"
         self.init(entity, key: key, modifiedAt: modifiedAt)
@@ -89,11 +82,11 @@ class EntityNode<T>: AnyEntityNode {
         }
 
         modifiedAt = newModifiedAt ?? modifiedAt
-        ref.value = newEntity
+        value = newEntity
     }
 
     func nullify() -> Bool {
-        if let value = ref.value as? Nullable {
+        if let value = value as? Nullable {
             do {
                 try updateEntity(value.nullified() as! T, modifiedAt: nil)
                 return true
@@ -126,12 +119,12 @@ class EntityNode<T>: AnyEntityNode {
         }
 
         if let writableKeyPath = keyPath as? WritableKeyPath<T, U.Value> {
-            ref.value[keyPath: writableKeyPath] = child.ref.value
+            value[keyPath: writableKeyPath] = child.value
             return
         }
 
         if let optionalWritableKeyPath = keyPath as? WritableKeyPath<T, U.Value?> {
-            ref.value[keyPath: optionalWritableKeyPath] = child.ref.value
+            value[keyPath: optionalWritableKeyPath] = child.value
             return
         }
 

Tests/CohesionKitTests/Observer/Stub/ObserverRegistryStub.swift

@@ -13,7 +13,7 @@ class ObserverRegistryStub: ObserverRegistry {
     }
 
     func hasPendingChange<T: Equatable>(for entity: T) -> Bool {
-        pendingChangesStub.contains { ($0 as? EntityNode<T>)?.ref.value == entity }
+        pendingChangesStub.contains { ($0 as? EntityNode<T>)?.value == entity }
     }
 
     func hasPendingChange<T>(for _: T.Type) -> Bool {
@@ -22,7 +22,7 @@ class ObserverRegistryStub: ObserverRegistry {
 
     /// number of times change has been inserted for this entity
     func pendingChangeCount<T: Equatable>(for entity: T) -> Int {
-        pendingChangesStub.filter { ($0 as? EntityNode<T>)?.ref.value == entity }.count
+        pendingChangesStub.filter { ($0 as? EntityNode<T>)?.value == entity }.count
     }
 
     func clearPendingChangesStub() {

Tests/CohesionKitTests/Storage/AliasStorageTests.swift

@@ -6,7 +6,7 @@ class AliasStorageTests: XCTestCase {
         var storage: AliasStorage = [:]
 
         XCTAssertNotNil(storage[safe: .testCollection])
-        XCTAssertNil(storage[safe: .testCollection].ref.value.content)
+        XCTAssertNil(storage[safe: .testCollection].value.content)
     }
 
     func test_subscriptGet_aliasHasSameNameThanAnotherType_itReturnsAliasContainer() {

Tests/CohesionKitTests/Storage/EntityNodeTests.swift

@@ -30,27 +30,27 @@ class EntityNodeTests: XCTestCase {
             try node.updateEntity(newEntity, modifiedAt: startTimestamp)
         )
 
-        XCTAssertEqual(node.value as? RootFixture, startEntity)
+        XCTAssertEqual(node.value, startEntity)
     }
 
     func test_updateEntity_stampIsSup_entityIsUpdated() throws {
         try node.updateEntity(newEntity, modifiedAt: startTimestamp + 1)
 
-        XCTAssertEqual(node.value as? RootFixture, newEntity)
+        XCTAssertEqual(node.value, newEntity)
     }
 
     func test_updateEntity_stampIsInf_entityIsNotUpdated() throws {
         XCTAssertThrowsError(
             try node.updateEntity(newEntity, modifiedAt: startTimestamp - 1)
         )
 
-        XCTAssertEqual(node.value as? RootFixture, startEntity)
+        XCTAssertEqual(node.value, startEntity)
     }
 
     func test_updateEntity_stampIsNil_entityIsUpdated() throws {
         try node.updateEntity(newEntity, modifiedAt: nil)
 
-        XCTAssertEqual(node.value as? RootFixture, newEntity)
+        XCTAssertEqual(node.value, newEntity)
     }
 
     func test_updateEntity_stampIsNil_stampIsNotUpdated() throws {
@@ -94,7 +94,7 @@ class EntityNodeTests: XCTestCase {
 
         node.updateEntityRelationship(childNode)
 
-        XCTAssertEqual(node.ref.value.singleNode, newChild)
+        XCTAssertEqual(node.value.singleNode, newChild)
     }
 
     func test_observeChild_childIsCollection_eachChildIsAdded() {