Merge pull request #6652 from woocommerce/issue/6649-free-shipping-option

Author: ealeksandrov

WooCommerce/Classes/ViewRelated/Orders/Order Creation/PaymentSection/ShippingLineDetailsViewModel.swift

@@ -21,7 +21,7 @@ class ShippingLineDetailsViewModel: ObservableObject {
 
     /// Placeholder for amount text field
     ///
-    let amountPlaceholder: String
+    let amountPlaceholder: String = "0"
 
     /// Stores the amount entered by the merchant.
     ///
@@ -36,7 +36,7 @@ class ShippingLineDetailsViewModel: ObservableObject {
     ///
     @Published var methodTitle: String
 
-    private let initialAmount: Decimal
+    private let initialAmount: Decimal?
     private let initialMethodTitle: String
 
     /// Returns true when existing shipping line is edited.
@@ -52,7 +52,7 @@ class ShippingLineDetailsViewModel: ObservableObject {
     /// Returns true when there are no valid pending changes.
     ///
     var shouldDisableDoneButton: Bool {
-        guard let amountDecimal = priceFieldFormatter.amountDecimal, amountDecimal != .zero else {
+        guard let amountDecimal = priceFieldFormatter.amountDecimal else {
             return true
         }
 
@@ -71,7 +71,6 @@ class ShippingLineDetailsViewModel: ObservableObject {
         self.priceFieldFormatter = .init(locale: locale, storeCurrencySettings: storeCurrencySettings, allowNegativeNumber: true)
         self.currencySymbol = storeCurrencySettings.symbol(from: storeCurrencySettings.currencyCode)
         self.currencyPosition = storeCurrencySettings.currencyPosition
-        self.amountPlaceholder = priceFieldFormatter.formatAmount("0")
 
         self.isExistingShippingLine = isExistingShippingLine
         self.initialMethodTitle = initialMethodTitle
@@ -81,10 +80,10 @@ class ShippingLineDetailsViewModel: ObservableObject {
         if let initialAmount = currencyFormatter.convertToDecimal(from: shippingTotal) {
             self.initialAmount = initialAmount as Decimal
         } else {
-            self.initialAmount = .zero
+            self.initialAmount = nil
         }
 
-        if initialAmount != .zero, let formattedInputAmount = currencyFormatter.formatAmount(initialAmount) {
+        if let initialAmount = initialAmount, let formattedInputAmount = currencyFormatter.formatAmount(initialAmount) {
             self.amount = priceFieldFormatter.formatAmount(formattedInputAmount)
         }
 

WooCommerce/WooCommerceTests/ViewRelated/Orders/Order Creation/ShippingLineDetailsViewModelTests.swift

@@ -158,9 +158,9 @@ final class ShippingLineDetailsViewModelTests: XCTestCase {
         // When
         viewModel.amount = "$11.30"
         viewModel.methodTitle = "Flat Rate"
+        viewModel.saveData()
 
         // Then
-        viewModel.saveData()
         XCTAssertEqual(savedShippingLine?.total, "11.30")
         XCTAssertEqual(savedShippingLine?.methodTitle, "Flat Rate")
     }
@@ -180,13 +180,34 @@ final class ShippingLineDetailsViewModelTests: XCTestCase {
         // When
         viewModel.amount = "-11.30"
         viewModel.methodTitle = "Flat Rate"
+        viewModel.saveData()
 
         // Then
-        viewModel.saveData()
         XCTAssertEqual(savedShippingLine?.total, "-11.30")
         XCTAssertEqual(savedShippingLine?.methodTitle, "Flat Rate")
     }
 
+    func test_view_model_allows_saving_zero_amount_and_creates_correct_shippping_line() {
+        // Given
+        var savedShippingLine: ShippingLine?
+        let viewModel = ShippingLineDetailsViewModel(isExistingShippingLine: false,
+                                                     initialMethodTitle: "",
+                                                     shippingTotal: "",
+                                                     locale: usLocale,
+                                                     storeCurrencySettings: usStoreSettings,
+                                                     didSelectSave: { newShippingLine in
+            savedShippingLine = newShippingLine
+        })
+
+        // When
+        viewModel.amount = "0"
+        viewModel.saveData()
+
+        // Then
+        XCTAssertFalse(viewModel.shouldDisableDoneButton)
+        XCTAssertEqual(savedShippingLine?.total, "0")
+    }
+
     func test_view_model_creates_shippping_line_with_placeholder_for_method_title() {
         // Given
         var savedShippingLine: ShippingLine?