wallet/reservation: Cancel needs to return an error

wallet/reservation.go

@@ -117,14 +117,14 @@ func (r *ChannelReservation) FinalFundingTx() *btcutil.Tx {
 
 // RequestFundingReserveCancellation...
 // TODO(roasbeef): also return mutated state?
-func (r *ChannelReservation) Cancel() {
-	doneChan := make(chan struct{}, 1)
+func (r *ChannelReservation) Cancel() error {
+	errChan := make(chan error, 1)
 	r.wallet.msgChan <- &fundingReserveCancelMsg{
 		pendingFundingID: r.reservationID,
-		done:             doneChan,
+		err:              errChan,
 	}
 
-	<-doneChan
+	return <-errChan
 }
 
 // WaitForChannelOpen...

wallet/wallet.go

@@ -88,7 +88,6 @@ type fundingReserveCancelMsg struct {
 
 	// Buffered, used for optionally synchronization.
 	err chan error // Buffered
-	done chan struct{} // Buffered
 }
 
 // addCounterPartySigsMsg...
@@ -430,7 +429,6 @@ func (l *LightningWallet) handleFundingCancelRequest(req *fundingReserveCancelMs
 	if !ok {
 		// TODO(roasbeef): make new error, "unkown funding state" or something
 		req.err <- fmt.Errorf("attempted to cancel non-existant funding state")
-		req.done <- struct{}{}
 		return
 	}
 
@@ -452,7 +450,6 @@ func (l *LightningWallet) handleFundingCancelRequest(req *fundingReserveCancelMs
 	delete(l.fundingLimbo, req.pendingFundingID)
 
 	req.err <- nil
-	req.done <- struct{}{}
 }
 
 // handleFundingCounterPartyFunds...