adobe_vipm/flows/helpers.py (1)

713-716: Consider explicit error handling for subscription fetch.

The get_subscriptions call is placed after the reseller_change_request succeeds but is not wrapped in its own try-except. If this call fails, the error will propagate with a generic message rather than a specific subscription-fetch error context.

This may be acceptable if subscription fetch failures should halt the flow entirely, but consider whether a more specific error message would help with debugging.

adobe_vipm/flows/validation/transfer.py (1)

649-661: Set-based comparison may incorrectly match orders with duplicate lines.

The current implementation uses sets for comparison, which loses multiplicity information. If there are duplicate (vendor, quantity) pairs, the comparison may incorrectly pass. For example:

• Order lines: [(SKU-A, 10), (SKU-A, 10), (SKU-B, 5)]
• Transfer lines: [(SKU-A, 10), (SKU-B, 5), (SKU-B, 5)]

Both would produce the same set {(SKU-A, 10), (SKU-B, 5)} despite representing different distributions.

If duplicate lines with identical (vendor, quantity) pairs can occur in practice, consider using collections.Counter instead:

from collections import Counter

def key(line: dict) -> tuple[str, int]:
    return (line["item"]["externalIds"]["vendor"], line["quantity"])

return Counter(map(key, order_lines)) == Counter(map(key, transfer_lines))

If duplicates are impossible by design, a clarifying comment would be helpful.

adobe_vipm/flows/validation/transfer.py (2)

588-594: Clarify intent: updating order with empty lines before validation failure.

When no transfer lines and no order lines exist, calling update_order with an empty order_lines_from_transfer list effectively clears the order. If this is intentional state synchronization, consider adding a brief comment explaining why this is needed before returning a validation failure.

---

673-685: Consider documenting the no-duplicates assumption.

The set-based comparison works correctly under the assumption that (vendor, quantity) pairs cannot repeat within the same order. A brief comment documenting this business constraint would help future maintainers understand why Counter isn't needed here.

     `@staticmethod`
     def _transfer_order_lines_match(order_lines: list[dict], transfer_lines: list[dict]) -> bool:
-        """Compare order lines based on relevant fields only."""
+        """Compare order lines based on relevant fields only.
+        
+        Note: Uses set comparison since duplicate (vendor, quantity) pairs
+        cannot occur within the same order per business rules.
+        """
         if len(order_lines) != len(transfer_lines):
             return False

tests/flows/validation/test_reseller_change.py (1)

599-602: Local mock override shadows the fixture.

The test_skip_one_time_skus method creates a local mock_get_one_time_skus patch that shadows the fixture from conftest. While this works, consider using mocker.patch to modify the fixture's return value instead, or parameterize the fixture to accept return values.

♻️ Alternative approach using fixture configuration

You could modify the conftest fixture to accept a parameter:

`@pytest.fixture`
def mock_get_one_time_skus(mocker, request):
    return_value = getattr(request, 'param', [])
    return mocker.patch(
        "adobe_vipm.flows.validation.transfer.get_one_time_skus",
        return_value=return_value,
        autospec=True,
    )

Then use @pytest.mark.parametrize("mock_get_one_time_skus", [["99999999CA"]], indirect=True) on specific tests.

tests/flows/validation/test_reseller_change.py (1)

207-287: Add a test for upsize-line rejection in reseller-change validation.

Once the upsize guard is enforced, add a test that creates an order with an upsize line (quantity increase) and asserts validation fails with the appropriate error and no preview order is requested.

Based on learnings: Rule: In reseller transfer validation flows (validate_reseller_change), upsize lines are not allowed as a business rule, only new lines are permitted.