Prototyping SwiftUI utilities

Sources/CoreDataNativeType.swift

@@ -33,7 +33,7 @@ import CoreData
  Objective-C Foundation types that are natively supported by Core Data managed attributes all conform to `CoreDataNativeType`.
  */
 @objc
-public protocol CoreDataNativeType: AnyObject, NSObjectProtocol {}
+public protocol CoreDataNativeType: NSObjectProtocol {}
 
 
 // MARK: - NSNumber

Sources/ForEach+SwiftUI.swift

@@ -0,0 +1,56 @@
+//
+//  ForEach+SwiftUI.swift
+//  CoreStore
+//
+//  Copyright © 2021 John Rommel Estropia
+//
+//  Permission is hereby granted, free of charge, to any person obtaining a copy
+//  of this software and associated documentation files (the "Software"), to deal
+//  in the Software without restriction, including without limitation the rights
+//  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+//  copies of the Software, and to permit persons to whom the Software is
+//  furnished to do so, subject to the following conditions:
+//
+//  The above copyright notice and this permission notice shall be included in all
+//  copies or substantial portions of the Software.
+//
+//  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+//  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+//  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+//  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+//  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+//  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+//  SOFTWARE.
+//
+
+#if canImport(Combine) && canImport(SwiftUI)
+
+import Combine
+import SwiftUI
+
+
+// MARK: - ForEach
+
+@available(iOS 13.0, macOS 10.15, tvOS 13.0, watchOS 6.0, *)
+extension ForEach where Content: View {
+    
+    // MARK: Public
+
+    public init<O: DynamicObject>(
+        _ listSnapshot: Data,
+        @ViewBuilder content: @escaping (ObjectPublisher<O>) -> Content
+    ) where Data == LiveList<O>.Items, ID == O.ObjectID {
+        
+        self.init(listSnapshot, id: \.cs_objectID, content: content)
+    }
+    
+    public init<O: DynamicObject>(
+        _ objectPublishers: Data,
+        @ViewBuilder content: @escaping (ObjectPublisher<O>) -> Content
+    ) where Data.Element == ObjectPublisher<O>, ID == O.ObjectID {
+        
+        self.init(objectPublishers, id: \.cs_objectID, content: content)
+    }
+}
+
+#endif

Sources/ForEachSection.swift

@@ -0,0 +1,59 @@
+//
+//  ForEachSection.swift
+//  CoreStore
+//
+//  Created by John Rommel Estropia on 2021/02/13.
+//  Copyright © 2021 John Rommel Estropia. All rights reserved.
+//
+
+#if canImport(Combine) && canImport(SwiftUI)
+
+import Combine
+import SwiftUI
+
+
+// MARK: - ForEachSection
+
+@available(iOS 13.0, tvOS 13.0, watchOS 6.0, macOS 10.15, *)
+public struct ForEachSection<Object: DynamicObject, Sections: View>: View {
+    
+    // MARK: Internal
+    
+    public init(
+        in listSnapshot: LiveList<Object>.Items,
+        @ViewBuilder sections: @escaping (
+            _ sectionID: ListSnapshot<Object>.SectionID,
+            _ objects: [ObjectPublisher<Object>]
+        ) -> Sections
+    ) {
+        
+        self.listSnapshot = listSnapshot
+        self.sections = sections
+    }
+    
+    
+    // MARK: View
+    
+    public var body: some View {
+        
+        ForEach(self.listSnapshot.sectionIDs, id: \.self) { sectionID in
+            
+            self.sections(
+                sectionID,
+                self.listSnapshot.items(inSectionWithID: sectionID)
+            )
+        }
+    }
+    
+    
+    // MARK: Private
+    
+    private let listSnapshot: LiveList<Object>.Items
+    
+    private let sections: (
+        _ sectionID: ListSnapshot<Object>.SectionID,
+        _ objects: [ObjectPublisher<Object>]
+    ) -> Sections
+}
+
+#endif

Sources/ListPublisher.swift

@@ -201,6 +201,14 @@ public final class ListPublisher<O: DynamicObject>: Hashable {
             }
         )
     }
+    
+    /**
+     Used internally by CoreStore. Do not call directly.
+     */
+    public func cs_dataStack() -> DataStack? {
+        
+        return self.context.parentStack
+    }
 
 
     // MARK: Public (3rd Party Utilities)

Sources/ListReader.swift

@@ -0,0 +1,78 @@
+//
+//  ListReader.swift
+//  CoreStore
+//
+//  Copyright © 2021 John Rommel Estropia
+//
+//  Permission is hereby granted, free of charge, to any person obtaining a copy
+//  of this software and associated documentation files (the "Software"), to deal
+//  in the Software without restriction, including without limitation the rights
+//  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+//  copies of the Software, and to permit persons to whom the Software is
+//  furnished to do so, subject to the following conditions:
+//
+//  The above copyright notice and this permission notice shall be included in all
+//  copies or substantial portions of the Software.
+//
+//  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+//  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+//  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+//  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+//  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+//  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+//  SOFTWARE.
+//
+
+#if canImport(Combine) && canImport(SwiftUI)
+
+import Combine
+import SwiftUI
+
+
+// MARK: - ListReader
+
+@available(iOS 13.0, tvOS 13.0, watchOS 6.0, macOS 10.15, *)
+public struct ListReader<Object: DynamicObject, Content: View, Value>: View {
+    
+    // MARK: Internal
+    
+    public init(
+        _ listPublisher: ListPublisher<Object>,
+        @ViewBuilder content: @escaping (Value) -> Content
+    ) where Value == LiveList<Object>.Items {
+        
+        self._list = .init(listPublisher)
+        self.content = content
+        self.keyPath = \.self
+    }
+    
+    public init(
+        _ listPublisher: ListPublisher<Object>,
+        keyPath: KeyPath<LiveList<Object>.Items, Value>,
+        @ViewBuilder content: @escaping (Value) -> Content
+    ) {
+        
+        self._list = .init(listPublisher)
+        self.content = content
+        self.keyPath = keyPath
+    }
+    
+    
+    // MARK: View
+    
+    public var body: some View {
+        
+        self.content(self.list[keyPath: self.keyPath])
+    }
+    
+    
+    // MARK: Private
+    
+    @LiveList
+    private var list: LiveList<Object>.Items
+    
+    private let content: (Value) -> Content
+    private let keyPath: KeyPath<LiveList<Object>.Items, Value>
+}
+
+#endif

Sources/LiveList.swift

@@ -0,0 +1,162 @@
+//
+//  LiveList.swift
+//  CoreStore
+//
+//  Copyright © 2021 John Rommel Estropia
+//
+//  Permission is hereby granted, free of charge, to any person obtaining a copy
+//  of this software and associated documentation files (the "Software"), to deal
+//  in the Software without restriction, including without limitation the rights
+//  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+//  copies of the Software, and to permit persons to whom the Software is
+//  furnished to do so, subject to the following conditions:
+//
+//  The above copyright notice and this permission notice shall be included in all
+//  copies or substantial portions of the Software.
+//
+//  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+//  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+//  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+//  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+//  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+//  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+//  SOFTWARE.
+//
+
+#if canImport(Combine) && canImport(SwiftUI)
+
+import Combine
+import SwiftUI
+
+
+// MARK: - LiveList
+
+@propertyWrapper
+@available(iOS 13.0, tvOS 13.0, watchOS 6.0, macOS 10.15, *)
+public struct LiveList<Object: DynamicObject>: DynamicProperty {
+    
+    // MARK: Public
+    
+    public typealias Items = ListSnapshot<Object>
+    
+    public init(
+        _ listPublisher: ListPublisher<Object>
+    ) {
+        
+        self.observer = .init(listPublisher: listPublisher)
+    }
+    
+    public init(
+        _ from: From<Object>,
+        _ fetchClauses: FetchClause...,
+        in dataStack: DataStack
+    ) {
+        
+        self.init(from, fetchClauses, in: dataStack)
+    }
+    
+    public init(
+        _ from: From<Object>,
+        _ fetchClauses: [FetchClause],
+        in dataStack: DataStack
+    ) {
+        
+        self.init(dataStack.publishList(from, fetchClauses))
+    }
+    
+    public init<B: FetchChainableBuilderType>(
+        _ clauseChain: B,
+        in dataStack: DataStack
+    ) where B.ObjectType == Object {
+        
+        self.init(dataStack.publishList(clauseChain))
+    }
+    
+    public init(
+        _ from: From<Object>,
+        _ sectionBy: SectionBy<Object>,
+        _ fetchClauses: FetchClause...,
+        in dataStack: DataStack
+    ) {
+        
+        self.init(from, sectionBy, fetchClauses, in: dataStack)
+    }
+    
+    public init(
+        _ from: From<Object>,
+        _ sectionBy: SectionBy<Object>,
+        _ fetchClauses: [FetchClause],
+        in dataStack: DataStack
+    ) {
+        
+        self.init(dataStack.publishList(from, sectionBy, fetchClauses))
+    }
+    
+    public init<B: SectionMonitorBuilderType>(
+        _ clauseChain: B,
+        in dataStack: DataStack
+    ) where B.ObjectType == Object {
+        
+        self.init(dataStack.publishList(clauseChain))
+    }
+    
+    
+    // MARK: @propertyWrapper
+    
+    public var wrappedValue: Items {
+        
+        return self.observer.items
+    }
+    
+    public var projectedValue: ListPublisher<Object> {
+        
+        return self.observer.listPublisher
+    }
+    
+    
+    // MARK: DynamicProperty
+    
+    public mutating func update() {
+        
+        self._observer.update()
+    }
+    
+    
+    // MARK: Private
+    
+    @ObservedObject
+    private var observer: Observer
+    
+    
+    // MARK: - Observer
+    
+    private final class Observer: ObservableObject {
+        
+        @Published
+        var items: Items
+        
+        let listPublisher: ListPublisher<Object>
+        
+        init(listPublisher: ListPublisher<Object>) {
+            
+            self.listPublisher = listPublisher
+            self.items = listPublisher.snapshot
+            
+            listPublisher.addObserver(self) { [weak self] (listPublisher) in
+                
+                guard let self = self else {
+                    
+                    return
+                }
+                self.items = listPublisher.snapshot
+            }
+        }
+        
+        deinit {
+            
+            self.listPublisher.removeObserver(self)
+        }
+    }
+}
+
+#endif

Sources/LiveObject.swift

@@ -0,0 +1,110 @@
+//
+//  LiveObject.swift
+//  CoreStore
+//
+//  Copyright © 2021 John Rommel Estropia
+//
+//  Permission is hereby granted, free of charge, to any person obtaining a copy
+//  of this software and associated documentation files (the "Software"), to deal
+//  in the Software without restriction, including without limitation the rights
+//  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+//  copies of the Software, and to permit persons to whom the Software is
+//  furnished to do so, subject to the following conditions:
+//
+//  The above copyright notice and this permission notice shall be included in all
+//  copies or substantial portions of the Software.
+//
+//  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+//  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+//  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+//  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+//  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+//  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+//  SOFTWARE.
+//
+
+#if canImport(Combine) && canImport(SwiftUI)
+
+import Combine
+import SwiftUI
+
+
+// MARK: - LiveObject
+
+@propertyWrapper
+@available(iOS 13.0, tvOS 13.0, watchOS 6.0, macOS 10.15, *)
+public struct LiveObject<O: DynamicObject>: DynamicProperty {
+    
+    // MARK: Public
+    
+    public typealias Item = ObjectSnapshot<O>
+    
+    public init(_ objectPublisher: ObjectPublisher<O>?) {
+        
+        self.observer = .init(objectPublisher: objectPublisher)
+    }
+    
+    
+    // MARK: @propertyWrapper
+    
+    public var wrappedValue: Item? {
+        
+        return self.observer.item
+    }
+    
+    
+    // MARK: DynamicProperty
+    
+    public mutating func update() {
+        
+        self._observer.update()
+    }
+    
+    
+    // MARK: Private
+    
+    @ObservedObject
+    private var observer: Observer
+    
+    
+    // MARK: - Observer
+    
+    private final class Observer: ObservableObject {
+        
+        @Published
+        var item: Item?
+        
+        let objectPublisher: ObjectPublisher<O>?
+        
+        init(objectPublisher: ObjectPublisher<O>?) {
+            
+            guard
+                let dataStack = objectPublisher?.cs_dataStack(),
+                let objectPublisher = objectPublisher?.asPublisher(in: dataStack)
+            else {
+                
+                self.objectPublisher = objectPublisher
+                self.item = nil
+                return
+            }
+            self.objectPublisher = objectPublisher
+            self.item = objectPublisher.snapshot
+            
+            objectPublisher.addObserver(self) { [weak self] (objectPublisher) in
+                
+                guard let self = self else {
+                    
+                    return
+                }
+                self.item = objectPublisher.snapshot
+            }
+        }
+        
+        deinit {
+            
+            self.objectPublisher?.removeObserver(self)
+        }
+    }
+}
+
+#endif

Sources/ObjectPublisher.swift

@@ -202,6 +202,11 @@ public final class ObjectPublisher<O: DynamicObject>: ObjectRepresentation, Hash
 
 
     // MARK: Internal
+    
+    internal var cs_objectID: O.ObjectID {
+        
+        return self.objectID()
+    }
 
     internal static func createUncached(objectID: O.ObjectID, context: NSManagedObjectContext) -> ObjectPublisher<O> {
 

Sources/ObjectReader.swift

@@ -1,9 +1,26 @@
 //
-//  ListState.swift
+//  ObjectReader.swift
 //  CoreStore
 //
-//  Created by John Rommel Estropia on 2020/12/26.
-//  Copyright © 2020 John Rommel Estropia. All rights reserved.
+//  Copyright © 2021 John Rommel Estropia
+//
+//  Permission is hereby granted, free of charge, to any person obtaining a copy
+//  of this software and associated documentation files (the "Software"), to deal
+//  in the Software without restriction, including without limitation the rights
+//  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+//  copies of the Software, and to permit persons to whom the Software is
+//  furnished to do so, subject to the following conditions:
+//
+//  The above copyright notice and this permission notice shall be included in all
+//  copies or substantial portions of the Software.
+//
+//  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+//  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+//  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+//  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+//  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+//  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+//  SOFTWARE.
 //
 
 #if canImport(Combine) && canImport(SwiftUI)
@@ -15,40 +32,29 @@ import SwiftUI
 // MARK: - ObjectReader
 
 @available(iOS 13.0, tvOS 13.0, watchOS 6.0, macOS 10.15, *)
-public struct ObjectReader<Object: DynamicObject, Content: View, Placeholder: View>: View {
+public struct ObjectReader<Object: DynamicObject, Content: View, Value>: View {
     
     // MARK: Internal
     
     public init(
         _ objectPublisher: ObjectPublisher<Object>?,
-        @ViewBuilder content: @escaping (ObjectSnapshot<Object>) -> Content,
-        @ViewBuilder placeholder: @escaping () -> Placeholder
-    ) {
+        @ViewBuilder content: @escaping (Value) -> Content
+    ) where Value == LiveObject<Object>.Item {
         
-        self.objectPublisher = .init(
-            objectPublisher.flatMap {
-                
-                guard let dataStack = $0.cs_dataStack() else {
-                    
-                    return nil
-                }
-                return $0.asPublisher(in: dataStack)
-            }
-        )
+        self._object = .init(objectPublisher)
         self.content = content
-        self.placeholder = placeholder
+        self.keyPath = \.self
     }
     
     public init(
         _ objectPublisher: ObjectPublisher<Object>?,
-        @ViewBuilder content: @escaping (ObjectSnapshot<Object>) -> Content
-    ) where Placeholder == EmptyView {
+        keyPath: KeyPath<LiveObject<Object>.Item, Value>,
+        @ViewBuilder content: @escaping (Value) -> Content
+    ) {
         
-        self.init(
-            objectPublisher,
-            content: content,
-            placeholder: EmptyView.init
-        )
+        self._object = .init(objectPublisher)
+        self.content = content
+        self.keyPath = keyPath
     }
     
     
@@ -56,45 +62,20 @@ public struct ObjectReader<Object: DynamicObject, Content: View, Placeholder: Vi
     
     public var body: some View {
         
-        if let snapshot = self.objectPublisher.wrappedValue?.snapshot {
+        if let object = self.object {
             
-            self.content(snapshot)
-        }
-        else {
-            
-            self.placeholder()
+            self.content(object[keyPath: self.keyPath])
         }
     }
     
     
     // MARK: Private
     
-    @ObservedObject
-    private var objectPublisher: OptionalObservedObject<ObjectPublisher<Object>>
+    @LiveObject
+    private var object: LiveObject<Object>.Item?
     
-    private let content: (ObjectSnapshot<Object>) -> Content
-    private let placeholder: () -> Placeholder
-    
-    
-    // MARK: - OptionalObservedObject
-    
-    fileprivate final class OptionalObservedObject<T: ObservableObject>: ObservableObject where ObservableObjectPublisher == T.ObjectWillChangePublisher {
-        
-        // MARK: Internal
-        
-        let wrappedValue: T?
-        
-        init(_ wrappedValue: T?) {
-            
-            self.wrappedValue = wrappedValue
-            self.objectWillChange = wrappedValue.map(\.objectWillChange) ?? .init()
-        }
-        
-        // MARK: ObservableObject
-        
-        let objectWillChange: ObservableObjectPublisher
-    }
+    private let content: (Value) -> Content
+    private let keyPath: KeyPath<LiveObject<Object>.Item, Value>
 }
 
 #endif
-

Sources/SectionsReader.swift

@@ -0,0 +1,65 @@
+//
+//  SectionsReader.swift
+//  CoreStore
+//
+//  Copyright © 2021 John Rommel Estropia
+//
+//  Permission is hereby granted, free of charge, to any person obtaining a copy
+//  of this software and associated documentation files (the "Software"), to deal
+//  in the Software without restriction, including without limitation the rights
+//  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+//  copies of the Software, and to permit persons to whom the Software is
+//  furnished to do so, subject to the following conditions:
+//
+//  The above copyright notice and this permission notice shall be included in all
+//  copies or substantial portions of the Software.
+//
+//  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+//  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+//  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+//  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+//  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+//  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+//  SOFTWARE.
+//
+
+#if canImport(Combine) && canImport(SwiftUI)
+
+import Combine
+import SwiftUI
+
+
+// MARK: - SectionsReader
+
+@available(iOS 13.0, tvOS 13.0, watchOS 6.0, macOS 10.15, *)
+public struct SectionsReader<Object: DynamicObject, Content: View>: View {
+    
+    // MARK: Internal
+    
+    public init(
+        _ listPublisher: ListPublisher<Object>,
+        @ViewBuilder content: @escaping (LiveList<Object>.Items) -> Content
+    ) {
+        
+        self._list = .init(listPublisher)
+        self.content = content
+    }
+    
+    
+    // MARK: View
+    
+    public var body: some View {
+        
+        self.content(self.list)
+    }
+    
+    
+    // MARK: Private
+    
+    @LiveList
+    private var list: LiveList<Object>.Items
+    
+    private let content: (LiveList<Object>.Items) -> Content
+}
+
+#endif