Fix issue

internal/validator/purchase_order_validator_test.go

@@ -73,3 +73,31 @@ func TestPurchaseOrderValidatorCreateRejectsDueDateBeforeTransactionDate(t *test
 	require.Equal(t, constants.MalformedFieldErrorCode, code)
 	require.Contains(t, err.Error(), "due_date must be after transaction_date")
 }
+
+func TestPurchaseOrderValidatorUpdateItemsRequireFullReplacementFields(t *testing.T) {
+	validator := NewPurchaseOrderValidator()
+	req := &contract.UpdatePurchaseOrderRequest{
+		Items: []contract.UpdatePurchaseOrderItemRequest{
+			{
+				PurchaseCategoryID: ptrUUID(uuid.New()),
+				Quantity:           ptrFloat64(1),
+				UnitID:             ptrUUID(uuid.New()),
+				Amount:             ptrFloat64(1000),
+			},
+		},
+	}
+
+	err, code := validator.ValidateUpdatePurchaseOrderRequest(req)
+
+	require.Error(t, err)
+	require.Equal(t, constants.MissingFieldErrorCode, code)
+	require.Contains(t, err.Error(), "ingredient_id is required")
+}
+
+func ptrUUID(id uuid.UUID) *uuid.UUID {
+	return &id
+}
+
+func ptrFloat64(value float64) *float64 {
+	return &value
+}