improve ergonomics and readability

Author: Mohammed Rokon Uddin

{{cookiecutter.app_name}}/Domain/Sources/Domain/Interface/UseCase.swift

@@ -8,9 +8,15 @@
 
 import Foundation
 
-public protocol UseCase {
+public protocol UseCase<Input, Output> {
   associatedtype Input
   associatedtype Output
 
-  func execute(input: Input) async throws -> Output
+  func callAsFunction(input: Input) async throws -> Output
+}
+
+extension UseCase where Input == Void {
+  public func callAsFunction() async throws -> Output {
+    try await callAsFunction(input: ())
+  }
 }

{{cookiecutter.app_name}}/Domain/Sources/Domain/UseCases/PrepareCoreDataUseCase.swift

@@ -8,13 +8,16 @@
 
 import Foundation
 
-public final class PrepareCoreDataUseCase: UseCase {
+public typealias PrepareCoreDataUseCaseType = UseCase<Void, Void>
+
+public class PrepareCoreDataUseCase: UseCase {
   var prepare: () async throws -> Void
+
   public init<R: PrepareRepository>(repository: R) {
     self.prepare = repository.prepare
   }
 
-  public func execute(input: Void) async {
+  public func callAsFunction(input: Void) async {
     try? await prepare()
   }
 }

{{cookiecutter.app_name}}/Domain/Sources/Domain/UseCases/ProductUseCase.swift

@@ -8,6 +8,8 @@
 
 import Foundation
 
+public typealias ProductUseCaseType = UseCase<Int, Product?>
+
 public final class ProductUseCase: UseCase {
 
   var getProduct: (_ input: Int) async throws -> Product?
@@ -17,7 +19,7 @@ public final class ProductUseCase: UseCase {
     self.getProduct = repository.read(input:)
   }
 
-  @Sendable public func execute(input: Int) async throws -> Product? {
+  public func callAsFunction(input: Int) async throws -> Product? {
     return try await getProduct(input)
   }
 }

{{cookiecutter.app_name}}/Domain/Sources/Domain/UseCases/SaveProductUseCase.swift

@@ -8,6 +8,8 @@
 
 import Foundation
 
+public typealias SaveProductUseCaseType = UseCase<Product, Void>
+
 public final class SaveProductUseCase: UseCase {
   var saveProduct: (_ input: Product) async throws -> Void
 
@@ -16,7 +18,7 @@ public final class SaveProductUseCase: UseCase {
     self.saveProduct = repository.create(input:)
   }
 
-  @Sendable public func execute(input: Product) async throws {
+  public func callAsFunction(input: Product) async throws {
     return try await saveProduct(input)
   }
 }

{{cookiecutter.app_name}}/Features/Sources/App/AppClient.swift

@@ -12,25 +12,24 @@ import Foundation
 import NetworkPlatform
 import PersistentPlatform
 
-public struct AppClient {
-  public var prepare: (()) async -> Void
-  public var save: @Sendable (_ request: Domain.Product) async throws -> Void
-  public var product: @Sendable (_ request: Int) async throws -> Domain.Product?
-}
+struct AppClient {
+  var getProduct: any ProductUseCaseType
+  var saveProduct: any SaveProductUseCaseType
+  var prepareCoreData: any PrepareCoreDataUseCaseType
 
-extension AppClient {
-  private init(
-    _ prepare: PrepareCoreDataUseCase, productUseCase: ProductUseCase,
-    saveProduct: SaveProductUseCase
+  init(
+    _ prepare: PrepareCoreDataUseCase,
+    getProductUseCase: ProductUseCase,
+    saveProductUseCase: SaveProductUseCase
   ) {
-    self.prepare = prepare.execute(input:)
-    self.save = saveProduct.execute(input:)
-    self.product = productUseCase.execute(input:)
+    self.prepareCoreData = prepare
+    self.getProduct = getProductUseCase
+    self.saveProduct = saveProductUseCase
   }
 }
 
 extension DependencyValues {
-  public var appClient: AppClient {
+  var appClient: AppClient {
     get { self[AppClient.self] }
     set { self[AppClient.self] = newValue }
   }
@@ -39,17 +38,17 @@ extension DependencyValues {
 extension AppClient: DependencyKey {
   public static var liveValue = AppClient(
     PrepareCoreDataUseCase(repository: PreparePersistentRepository.live),
-    productUseCase: ProductUseCase(repository: RemoteProductRepository.live),
-    saveProduct: SaveProductUseCase(
+    getProductUseCase: ProductUseCase(repository: RemoteProductRepository.live),
+    saveProductUseCase: SaveProductUseCase(
       repository: PersistentProductRepository.live))
   public static var testValue = AppClient(
     PrepareCoreDataUseCase(repository: PreparePersistentRepository.live),
-    productUseCase: ProductUseCase(repository: RemoteProductRepository.stubbed),
-    saveProduct: SaveProductUseCase(
+    getProductUseCase: ProductUseCase(repository: RemoteProductRepository.stubbed),
+    saveProductUseCase: SaveProductUseCase(
       repository: PersistentProductRepository.live))
   public static var previewValue = AppClient(
     PrepareCoreDataUseCase(repository: PreparePersistentRepository.live),
-    productUseCase: ProductUseCase(repository: RemoteProductRepository.stubbed),
-    saveProduct: SaveProductUseCase(
+    getProductUseCase: ProductUseCase(repository: RemoteProductRepository.stubbed),
+    saveProductUseCase: SaveProductUseCase(
       repository: PersistentProductRepository.live))
 }

{{cookiecutter.app_name}}/Features/Sources/App/AppFeature.swift

@@ -50,12 +50,12 @@ public struct AppFeature: FeatureReducer {
     switch viewAction {
     case .onAppear:
       return .run { send in
-        await appClient.prepare(Void())
+        try? await appClient.prepareCoreData()
         await send(
           .internal(
             .productResponse(
               Result {
-                try await appClient.product(1)
+                try await appClient.getProduct(input: 2)
               })))
       }
     case .showSheet:
@@ -69,7 +69,7 @@ public struct AppFeature: FeatureReducer {
     case .save:
       return .run { [product = state.product] send in
         do {
-          try await appClient.save(product!)
+          try await appClient.saveProduct(input: product!)
         } catch {
 
         }

{{cookiecutter.app_name}}/{{cookiecutter.app_name}}.xcodeproj/project.xcworkspace/xcshareddata/swiftpm/Package.resolved

@@ -75,7 +75,7 @@
     {
       "identity" : "swift-composable-architecture",
       "kind" : "remoteSourceControl",
-      "location" : "https://github.com/pointfreeco/swift-composable-architecture",
+      "location" : "git@github.com:pointfreeco/swift-composable-architecture.git",
       "state" : {
         "revision" : "cf967a28a8605629559533320d604168d733fc9c",
         "version" : "1.8.0"