changes according to the test

repositories/stockLedger.go

@@ -180,3 +180,31 @@ func legacyOrderQty(quantity float64) int {
 	}
 	return q
 }
+
+// assertOutletNamed refuses an order that does not say which shop it is for.
+//
+// Stock is held per outlet — availableStock filters `locationid = ?` — so a
+// line with no outlet matches no ledger row and reads as zero available. Every
+// such order was then refused as "insufficient stock ... available 0", naming
+// the shelf as the problem when the shelf was full and the request was what was
+// incomplete. A merchant reading that goes and checks their stock, finds it,
+// and has nowhere else to look.
+//
+// Per line rather than per order: a line may carry its own outlet, and only
+// falls back to the header's when it does not.
+func assertOutletNamed(lines []stockLine) error {
+	for _, line := range lines {
+		if line.Locationid != 0 {
+			continue
+		}
+		name := line.Productname
+		if name == "" {
+			name = fmt.Sprintf("ID %d", line.Productid)
+		}
+		return fmt.Errorf(
+			"this order names no outlet, so there is no shelf to sell '%s' from: "+
+				"send locationid on the order, or on each item", name,
+		)
+	}
+	return nil
+}