[Woo POS][Barcodes] Prevent checkout with scans in loading state (#15727)

Author: joshheald

WooCommerce/Classes/POS/Presentation/CartView.swift

@@ -280,6 +280,7 @@ private extension CartView {
             Text(Localization.checkoutButtonTitle)
         }
         .buttonStyle(POSFilledButtonStyle(size: .normal))
+        .disabled(CartViewHelper().hasUnresolvedItems(cart: posModel.cart))
     }
 
     var backButtonConfiguration: POSPageHeaderBackButtonConfiguration? {

WooCommerce/Classes/POS/ViewHelpers/CartViewHelper.swift

@@ -27,6 +27,15 @@ struct CartViewHelper {
 
         return cart.purchasableItems.isNotEmpty
     }
+
+    func hasUnresolvedItems(cart: Cart) -> Bool {
+        cart.purchasableItems.contains { item in
+            if case .loading = item.state {
+                return true
+            }
+            return false
+        }
+    }
 }
 
 private extension PointOfSalePaymentState {

WooCommerce/WooCommerceTests/POS/ViewHelpers/CartViewHelperTests.swift

@@ -214,6 +214,41 @@ struct CartViewHelperTests {
         // When, Then
         #expect(sut.shouldShowCheckout(orderStage: .building, cart: cart) == true)
     }
+
+    @Test func hasUnresolvedItems_when_cart_is_empty_returns_false() async throws {
+        // Given
+        let cart = Cart()
+
+        // When, Then
+        #expect(sut.hasUnresolvedItems(cart: cart) == false)
+    }
+
+    @Test func hasUnresolvedItems_when_cart_has_only_loaded_items_returns_false() async throws {
+        // Given
+        let cart = Cart(purchasableItems: [makeItem()])
+
+        // When, Then
+        #expect(sut.hasUnresolvedItems(cart: cart) == false)
+    }
+
+    @Test func hasUnresolvedItems_when_cart_has_loading_item_returns_true() async throws {
+        // Given
+        let loadingItem = Cart.PurchasableItem.loading(id: UUID())
+        let cart = Cart(purchasableItems: [loadingItem])
+
+        // When, Then
+        #expect(sut.hasUnresolvedItems(cart: cart) == true)
+    }
+
+    @Test func hasUnresolvedItems_when_cart_has_mixed_items_returns_true() async throws {
+        // Given
+        let loadingItem = Cart.PurchasableItem.loading(id: UUID())
+        let loadedItem = makeItem()
+        let cart = Cart(purchasableItems: [loadingItem, loadedItem])
+
+        // When, Then
+        #expect(sut.hasUnresolvedItems(cart: cart) == true)
+    }
 }
 
 private func makeItem() -> Cart.PurchasableItem {