update due date and range date

internal/transformer/purchase_order_transformer_test.go

@@ -0,0 +1,43 @@
+package transformer
+
+import (
+	"encoding/json"
+	"testing"
+
+	"apskel-pos-be/internal/contract"
+	"apskel-pos-be/internal/models"
+
+	"github.com/google/uuid"
+	"github.com/stretchr/testify/require"
+)
+
+func TestCreatePurchaseOrderRequestToModelAllowsMissingDueDate(t *testing.T) {
+	result, err := CreatePurchaseOrderRequestToModel(&contract.CreatePurchaseOrderRequest{
+		VendorID:        uuid.New(),
+		PONumber:        "PO-001",
+		TransactionDate: "2026-05-29",
+		Items: []contract.CreatePurchaseOrderItemRequest{
+			{
+				IngredientID: uuid.New(),
+				Quantity:     1,
+				UnitID:       uuid.New(),
+				Amount:       1000,
+			},
+		},
+	})
+
+	require.NoError(t, err)
+	require.Nil(t, result.DueDate)
+}
+
+func TestPurchaseOrderModelResponseToResponseIncludesNullDueDate(t *testing.T) {
+	result := PurchaseOrderModelResponseToResponse(&models.PurchaseOrderResponse{
+		ID:       uuid.New(),
+		VendorID: uuid.New(),
+		PONumber: "PO-001",
+	})
+
+	payload, err := json.Marshal(result)
+	require.NoError(t, err)
+	require.Contains(t, string(payload), `"due_date":null`)
+}