From f90788667968ffc3adbe3622a6d4aa5331a1a9d9 Mon Sep 17 00:00:00 2001
From: Bianca Severino <bseverino@redventures.com>
Date: Thu, 30 Apr 2026 09:04:46 -0400
Subject: [PATCH 1/2] fix: cast refund amount to string for paypal

---
 commerce_coordinator/apps/paypal/clients.py   |  5 ++-
 .../apps/paypal/tests/test_clients.py         | 40 +++++++++++++++++++
 2 files changed, 44 insertions(+), 1 deletion(-)
 create mode 100644 commerce_coordinator/apps/paypal/tests/test_clients.py

diff --git a/commerce_coordinator/apps/paypal/clients.py b/commerce_coordinator/apps/paypal/clients.py
index b44680adf..2f2038c26 100644
--- a/commerce_coordinator/apps/paypal/clients.py
+++ b/commerce_coordinator/apps/paypal/clients.py
@@ -32,6 +32,9 @@ def refund_order(self, capture_id, amount):
 
         Args:
             capture_id (str): The identifier of the PayPal order to capture refund.
+            amount (decimal.Decimal | int | float): Refund amount; coerced to str for the
+                request body because the PayPal SDK serializes the body with jsonpickle,
+                which encodes Decimal as null (PayPal expects Money.value as a string).
 
         Returns:
             The response from PayPal.
@@ -45,7 +48,7 @@ def refund_order(self, capture_id, amount):
             "prefer": "return=representation",
             "body": {
                 "amount": {
-                    "value": amount,
+                    "value": str(amount),
                     "currency_code": "USD"
                 }
             }
diff --git a/commerce_coordinator/apps/paypal/tests/test_clients.py b/commerce_coordinator/apps/paypal/tests/test_clients.py
new file mode 100644
index 000000000..253d743a8
--- /dev/null
+++ b/commerce_coordinator/apps/paypal/tests/test_clients.py
@@ -0,0 +1,40 @@
+"""Tests for PayPal API client."""
+
+import json
+from decimal import Decimal
+from unittest.mock import MagicMock, patch
+
+from django.test import TestCase
+
+from commerce_coordinator.apps.paypal.clients import PayPalClient
+
+
+class PayPalClientRefundOrderTests(TestCase):
+    """Regression tests for refund_order request shaping."""
+
+    @patch("commerce_coordinator.apps.paypal.clients.PaypalServersdkClient")
+    @patch("commerce_coordinator.apps.paypal.clients.ApiHelper.json_serialize")
+    def test_refund_order_serializes_decimal_amount_as_string(
+        self, mock_json_serialize, mock_sdk_class
+    ):
+        """
+        PayPal Money.value is a string. The SDK body uses jsonpickle, which emits null
+        for Decimal unless we pass a string (see get_line_item_price_to_refund Decimal).
+        """
+        mock_json_serialize.return_value = json.dumps(
+            {
+                "id": "REFUND_ID",
+                "create_time": "2024-01-01T00:00:00Z",
+                "status": "COMPLETED",
+                "amount": {"value": "49.00", "currency_code": "USD"},
+            }
+        )
+        mock_payments = MagicMock()
+        mock_sdk_class.return_value.payments = mock_payments
+
+        client = PayPalClient()
+        client.refund_order("CAPTURE_ID", Decimal("49.00"))
+
+        mock_payments.refund_captured_payment.assert_called_once()
+        collect = mock_payments.refund_captured_payment.call_args[0][0]
+        self.assertEqual(collect["body"]["amount"]["value"], "49.00")

From 5d81724981f690f6037915754aa3ffa56539e4d9 Mon Sep 17 00:00:00 2001
From: Bianca Severino <bseverino@redventures.com>
Date: Thu, 30 Apr 2026 09:12:33 -0400
Subject: [PATCH 2/2] fix: clarify test docstring

Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>
---
 commerce_coordinator/apps/paypal/tests/test_clients.py | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/commerce_coordinator/apps/paypal/tests/test_clients.py b/commerce_coordinator/apps/paypal/tests/test_clients.py
index 253d743a8..0ef5ab73b 100644
--- a/commerce_coordinator/apps/paypal/tests/test_clients.py
+++ b/commerce_coordinator/apps/paypal/tests/test_clients.py
@@ -18,8 +18,9 @@ def test_refund_order_serializes_decimal_amount_as_string(
         self, mock_json_serialize, mock_sdk_class
     ):
         """
-        PayPal Money.value is a string. The SDK body uses jsonpickle, which emits null
-        for Decimal unless we pass a string (see get_line_item_price_to_refund Decimal).
+        PayPal Money.value is a string. The refund amount may come from
+        get_line_item_price_to_refund as a Decimal, and the SDK body uses
+        jsonpickle, which emits null for Decimal unless we pass a string.
         """
         mock_json_serialize.return_value = json.dumps(
             {