[sales] Do not call onSale() when someone else's offer is selected

dagger/sales.nim

@@ -70,7 +70,8 @@ proc handleRequest(sales: Sales, request: StorageRequest) {.async.} =
   proc onSelect(offerId: array[32, byte]) {.gcsafe, upraises:[].} =
     if subscription =? subscription:
       asyncSpawn subscription.unsubscribe()
-    sales.onSale(offer)
+    if offer.id == offerId:
+      sales.onSale(offer)
   subscription = some await sales.market.subscribeSelection(request.id, onSelect)
 
 proc start*(sales: Sales) =

tests/dagger/testsales.nim

@@ -88,3 +88,18 @@ suite "Sales":
     await market.selectOffer(offer.id)
     check selectedOffer == offer
     sales.stop()
+
+  test "does not call onSale when a different offer is selected":
+    let availability = Availability.init(size=100, duration=60, minPrice=42.u256)
+    sales.add(availability)
+    var onSaleWasCalled: bool
+    sales.onSale = proc(offer: StorageOffer) =
+      onSaleWasCalled = true
+    sales.start()
+    var request = StorageRequest(duration:60.u256, size:100.u256, maxPrice:42.u256)
+    request = await market.requestStorage(request)
+    var otherOffer = StorageOffer(requestId: request.id, price: 1.u256)
+    otherOffer = await market.offerStorage(otherOffer)
+    await market.selectOffer(otherOffer.id)
+    check not onSaleWasCalled
+    sales.stop()