From 574488031ce6d2e3d31ef0c23459151b8bedf226 Mon Sep 17 00:00:00 2001
From: Peter Kvayt <peter.kvayt@gmail.com>
Date: Thu, 11 Jul 2024 13:25:56 +0200
Subject: [PATCH] Add exception to clearify what exactly was happened.

---
 .../PayPalCheckoutOneTimePaymentProvider.cs                   | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/src/Umbraco.Commerce.PaymentProviders.PayPal/PayPalCheckoutOneTimePaymentProvider.cs b/src/Umbraco.Commerce.PaymentProviders.PayPal/PayPalCheckoutOneTimePaymentProvider.cs
index dbf284a..8d8151a 100644
--- a/src/Umbraco.Commerce.PaymentProviders.PayPal/PayPalCheckoutOneTimePaymentProvider.cs
+++ b/src/Umbraco.Commerce.PaymentProviders.PayPal/PayPalCheckoutOneTimePaymentProvider.cs
@@ -122,7 +122,9 @@ public override async Task<PaymentFormResult> GenerateFormAsync(PaymentProviderC
                 cancellationToken).ConfigureAwait(false);
 
             // Setup the payment form to redirect to approval link
-            var approveLink = payPalOrder.Links.FirstOrDefault(x => x.Rel == "approve");
+            const string REL_APPROVE = "approve";
+            var approveLink = payPalOrder.Links.FirstOrDefault(x => x.Rel == REL_APPROVE)
+                ?? throw new InvalidOperationException($"PayPal order link with {nameof(PayPalHateoasLink.Rel)}=\"{REL_APPROVE}\" was null.");
             var approveLinkMethod = (PaymentFormMethod)Enum.Parse(typeof(PaymentFormMethod), approveLink.Method, true);
 
             return new PaymentFormResult()