fix bot issues

lib/torrent.js

@@ -114,7 +114,7 @@ class Torrent extends EventEmitter {
     this._servers = []
     this._xsRequests = []
 
-    this._writeCb = opts.writeCb,
+    this._writeCb = opts.writeCb
 
     // TODO: remove this and expose a hook instead
     // optimization: don't recheck every file if it hasn't changed
@@ -1602,7 +1602,10 @@ class Torrent extends EventEmitter {
     let read = 0;
     const writable = new ChunkStoreWriteStream(this.store, this.pieceLength)
     if (this._writeCb) {
-      writable._blockstream.on('data', data => this._writeCb(this.length, read += data.length))
+      writable._blockstream.on('data', data => {
+        read += data.length
+        this._writeCb(this.length, read)
+      })
     }
 
     pump(readable, writable, err => {