Fix missing trackers adding magnets

The changes to remove deprecated lt methods didn't account for magnet
trackers so magnets are missing trackers when added.

Previously the addition of trackers was handled by libtorrent when a url
was passed in add_torrent_params. The url parameter is deprecated so
instead we need to add both the info_hash and trackers.

Trac: https://dev.deluge-torrent.org/ticket/3530

deluge/core/torrentmanager.py

@@ -436,8 +436,8 @@ class TorrentManager(component.Component):
             magnet_info = get_magnet_info(magnet)
             if magnet_info:
                 add_torrent_params['name'] = magnet_info['name']
+                add_torrent_params['trackers'] = list(magnet_info['trackers'])
                 torrent_id = magnet_info['info_hash']
-                # Workaround lt 1.2 bug for magnet resume data with no metadata
                 add_torrent_params['info_hash'] = bytes(bytearray.fromhex(torrent_id))
             else:
                 raise AddTorrentError(

deluge/tests/test_core.py

@@ -222,10 +222,15 @@ class TestCore(BaseTestCase):
     @pytest_twisted.inlineCallbacks
     def test_add_torrent_magnet(self):
         info_hash = '60d5d82328b4547511fdeac9bf4d0112daa0ce00'
-        uri = deluge.common.create_magnet_uri(info_hash)
+        tracker = 'udp://tracker.example.com'
+        name = 'test magnet'
+        uri = deluge.common.create_magnet_uri(info_hash, name=name, trackers=[tracker])
         options = {}
         torrent_id = yield self.core.add_torrent_magnet(uri, options)
         assert torrent_id == info_hash
+        torrent_status = self.core.get_torrent_status(torrent_id, ['name', 'trackers'])
+        assert torrent_status['trackers'][0]['url'] == tracker
+        assert torrent_status['name'] == name
 
     def test_resume_torrent(self):
         tid1 = self.add_torrent('test.torrent', paused=True)