feat: Working on mocks and mock storage.

Sources/DatabaseClient/MockStorage.swift

@@ -0,0 +1,143 @@
+#if DEBUG
+  import Dependencies
+  import Vapor
+
+  actor MockStorage<
+    Model: Identifiable,
+    Create: Sendable,
+    Fetch: Sendable,
+    Get: Sendable,
+    Update: Sendable
+  > where Model: Sendable {
+    @Dependency(\.date.now) var now
+    @Dependency(\.uuid) var uuid
+
+    private var storage: [Model.ID: Model]
+
+    private let modelFromCreate: @Sendable (Create) -> Model
+    private let fetchToPredicate: @Sendable (Fetch) -> ((Model) -> Bool)
+    private let fetchExtras: @Sendable (Fetch, [Model]) async throws -> [Model]
+    private let applyUpdates: @Sendable (inout Model, Update, Get?) async throws -> Void
+    private let getExtras: @Sendable (Get?, Model) async throws -> Model
+
+    init(
+      _ mocks: [Model] = [],
+      create modelFromCreate: @Sendable @escaping (Create) -> Model,
+      fetch fetchToPredicate: @Sendable @escaping (Fetch) -> ((Model) -> Bool),
+      fetchExtras: @Sendable @escaping (Fetch, [Model]) async throws -> [Model] = { $1 },
+      get getExtras: @Sendable @escaping (Get?, Model) async throws -> Model,
+      update applyUpdates: @Sendable @escaping (inout Model, Update, Get?) async throws -> Void
+    ) {
+      self.storage = mocks.reduce(into: [Model.ID: Model]()) { $0[$1.id] = $1 }
+      self.modelFromCreate = modelFromCreate
+      self.fetchToPredicate = fetchToPredicate
+      self.fetchExtras = fetchExtras
+      self.applyUpdates = applyUpdates
+      self.getExtras = getExtras
+    }
+
+    func count() async throws -> Int {
+      storage.count
+    }
+
+    func create(_ create: Create) async throws -> Model {
+      let model = modelFromCreate(create)
+      storage[model.id] = model
+      return model
+    }
+
+    func delete(_ id: Model.ID) async throws {
+      storage[id] = nil
+    }
+
+    func fetchAll(_ request: Fetch) async throws -> [Model] {
+      let predicate = fetchToPredicate(request)
+      return try await fetchExtras(request, Array(storage.values.filter { predicate($0) }))
+    }
+
+    func get(_ id: Model.ID, _ request: Get?) async throws -> Model? {
+      if let model = storage[id] {
+        return try await getExtras(request, model)
+      }
+      return nil
+    }
+
+    func update(_ id: Model.ID, _ updates: Update, _ get: Get?) async throws -> Model {
+      guard var model = storage[id] else {
+        throw Abort(.badRequest, reason: "Model not found.")
+      }
+      try await applyUpdates(&model, updates, get)
+      storage[id] = model
+      return model
+    }
+  }
+
+  extension MockStorage where Get == Void {
+    init(
+      _ mocks: [Model] = [],
+      create modelFromCreate: @Sendable @escaping (Create) -> Model,
+      fetch fetchToPredicate: @Sendable @escaping (Fetch) -> ((Model) -> Bool),
+      fetchExtras: @Sendable @escaping (Fetch, [Model]) async throws -> [Model] = { $1 },
+      update applyUpdates: @Sendable @escaping (inout Model, Update) async throws -> Void
+    ) {
+      self.init(
+        mocks,
+        create: modelFromCreate,
+        fetch: fetchToPredicate,
+        fetchExtras: fetchExtras,
+        get: { _, model in model },
+        update: { model, updates, _ in try await applyUpdates(&model, updates) }
+      )
+    }
+
+    func get(_ id: Model.ID) async throws -> Model? {
+      storage[id]
+    }
+
+    func update(_ id: Model.ID, _ updates: Update) async throws -> Model {
+      try await update(id, updates, ())
+    }
+
+  }
+
+  extension MockStorage where Fetch == Void {
+    init(
+      _ mocks: [Model] = [],
+      create modelFromCreate: @Sendable @escaping (Create) -> Model,
+      fetchExtras: @Sendable @escaping (Fetch, [Model]) async throws -> [Model] = { $1 },
+      get getExtras: @Sendable @escaping (Get?, Model) async throws -> Model,
+      update applyUpdates: @Sendable @escaping (inout Model, Update, Get?) async throws -> Void
+    ) {
+      self.init(
+        mocks,
+        create: modelFromCreate,
+        fetch: { _ in { _ in true } },
+        fetchExtras: fetchExtras,
+        get: getExtras,
+        update: applyUpdates
+      )
+    }
+
+    func fetchAll() async throws -> [Model] {
+      try await fetchAll(())
+    }
+  }
+
+  extension MockStorage where Fetch == Void, Get == Void {
+    init(
+      _ mocks: [Model] = [],
+      create modelFromCreate: @Sendable @escaping (Create) -> Model,
+      fetchExtras: @Sendable @escaping (Fetch, [Model]) async throws -> [Model] = { $1 },
+      update applyUpdates: @Sendable @escaping (inout Model, Update) async throws -> Void
+    ) {
+      self.init(
+        mocks,
+        create: modelFromCreate,
+        fetchExtras: fetchExtras,
+        get: { _, model in model },
+        update: { model, updates, _ in try await applyUpdates(&model, updates) }
+      )
+    }
+
+  }
+#endif