[V6] Accept email in BTPayPalVaultRequest (#1223)

CHANGELOG.md

@@ -1,5 +1,8 @@
 # Braintree iOS SDK Release Notes
 
+## unreleased
+* Add `BTPayPalVaultRequest.userAuthenticationEmail` optional property
+
 ## 6.15.0 (2024-03-18)
 * [Meets Apple's new Privacy Update requirements](https://developer.apple.com/news/?id=3d8a9yyh)
 

Sources/BraintreePayPal/BTPayPalVaultRequest.swift

@@ -11,13 +11,17 @@ import BraintreeCore
 
     /// Optional: Offers PayPal Credit if the customer qualifies. Defaults to `false`.
     public var offerCredit: Bool
+
+    /// Optional: User email to initiate a quicker authentication flow in cases where the user has a PayPal Account with the same email.
+    public var userAuthenticationEmail: String?
 
     // MARK: - Initializer
 
     /// Initializes a PayPal Native Vault request
     /// - Parameter offerCredit: Optional: Offers PayPal Credit if the customer qualifies. Defaults to `false`.
-    public init(offerCredit: Bool = false) {
+    public init(offerCredit: Bool = false, userAuthenticationEmail: String? = nil) {
         self.offerCredit = offerCredit
+        self.userAuthenticationEmail = userAuthenticationEmail
 
         super.init(hermesPath: "v1/paypal_hermes/setup_billing_agreement", paymentType: .vault)
     }
@@ -30,9 +34,13 @@ import BraintreeCore
         let baseParameters = super.parameters(with: configuration)
         var vaultParameters: [String: Any] = ["offer_paypal_credit": offerCredit]
 
-        if billingAgreementDescription != nil {
+        if let billingAgreementDescription {
             vaultParameters["description"] = billingAgreementDescription
         }
+
+        if let userAuthenticationEmail {
+            vaultParameters["payer_email"] = userAuthenticationEmail
+        }
 
         if let shippingAddressOverride {
             let shippingAddressParameters: [String: String?] = [

UnitTests/BraintreePayPalTests/BTPayPalVaultRequest_Tests.swift

@@ -47,11 +47,13 @@ class BTPayPalVaultRequest_Tests: XCTestCase {
         request.shippingAddressOverride = shippingAddress
         request.isShippingAddressEditable = true
         request.offerCredit = true
+        request.userAuthenticationEmail = "[email protected]"
 
         let parameters = request.parameters(with: configuration)
 
         XCTAssertEqual(parameters["description"] as? String, "desc")
         XCTAssertEqual(parameters["offer_paypal_credit"] as? Bool, true)
+        XCTAssertEqual(parameters["payer_email"] as? String, "[email protected]")
 
         guard let shippingParams = parameters["shipping_address"] as? [String:String] else { XCTFail(); return }