Fix panic in connection.iterPendingPieces when the info isn't available

Triggered by connection.iterUnbiasedPieceRequestOrder calling Torrent.numPieces. We shouldn't be iterating pieces when there's no info anyway, so don't yield any. Mentioned in https://github.com/anacrolix/torrent/issues/253#issuecomment-400350386.

diff --git a/connection.go b/connection.go
index 63a0da6b47c4afe771aed58f011f6a51ff20b6eb..0c3bc1c4898de120ddd9346109ecd3fd16c0a46a 100644 (file)
--- a/connection.go
+++ b/connection.go
@@ -739,6 +739,9 @@ func (cn *connection) shouldRequestWithoutBias() bool {
 }
 
 func (cn *connection) iterPendingPieces(f func(int) bool) bool {
+       if !cn.t.haveInfo() {
+               return false
+       }
        if cn.t.requestStrategy == 3 {
                return cn.iterUnbiasedPieceRequestOrder(f)
        }