feat: Working on mocks and mock storage.

Sources/DatabaseClient/VendorBranches.swift

@@ -15,7 +15,6 @@ public extension DatabaseClient {
     public enum FetchRequest: Equatable {
       case all
       case `for`(vendorID: Vendor.ID)
-      case withVendor
     }
 
     public func fetchAll() async throws -> [VendorBranch] {
@@ -32,3 +31,61 @@ extension DatabaseClient.VendorBranches.FetchRequest: Content {}
 extension DatabaseClient.VendorBranches: TestDependencyKey {
   public static let testValue: DatabaseClient.VendorBranches = Self()
 }
+
+#if DEBUG
+  typealias VendorBranchMockStorage = MockStorage<
+    VendorBranch,
+    VendorBranch.Create,
+    DatabaseClient.VendorBranches.FetchRequest,
+    Void,
+    VendorBranch.Update
+  >
+
+  private extension VendorBranchMockStorage {
+
+    init(_ mocks: [VendorBranch]) {
+      @Dependency(\.date.now) var now
+      @Dependency(\.uuid) var uuid
+
+      self.init(
+        mocks,
+        create: {
+          VendorBranch(id: uuid(), name: $0.name, vendorID: $0.vendorID, createdAt: now, updatedAt: now)
+        },
+        fetch: { request in
+          switch request {
+          case .all:
+            return { _ in true }
+          case let .for(vendorID):
+            return { $0.vendorID == vendorID }
+          }
+        },
+        update: { branch, updates in
+          let model = VendorBranch(
+            id: branch.id,
+            name: updates.name ?? branch.name,
+            vendorID: branch.vendorID,
+            createdAt: branch.createdAt,
+            updatedAt: now
+          )
+
+          branch = model
+        }
+      )
+    }
+  }
+
+  public extension DatabaseClient.VendorBranches {
+    static func mock(_ mocks: [VendorBranch] = []) -> Self {
+      let storage = VendorBranchMockStorage(mocks)
+      return .init(
+        create: { try await storage.create($0) },
+        delete: { try await storage.delete($0) },
+        fetchAll: { try await storage.fetchAll($0) },
+        get: { try await storage.get($0) },
+        update: { try await storage.update($0, $1) }
+      )
+    }
+  }
+
+#endif