Go back to Twisted event loop

Urwid + asyncio has been known to have very high CPU usage for 4 years
now, and it hasn't been fixed. That basically makes it impossible to
switch event loops. We can still get the asyncio syntax goodness but
using the twisted asyncioreactor and then initializing urwid with the
Twisted loop which doesn't have this problem.

Fixes #1302

3 files changed, 5 insertions, 1 deletions

diff --git a/alot/__main__.py b/alot/__main__.py
index 221e6b22..c901bb07 100644
--- a/alot/__main__.py
+++ b/alot/__main__.py
@@ -16,6 +16,9 @@ from alot.commands import *
 from alot.commands import CommandParseError, COMMANDS
 from alot.utils import argparse as cargparse
 
+from twisted.internet import asyncioreactor
+asyncioreactor.install()
+
 
 _SUBCOMMANDS = ['search', 'compose', 'bufferlist', 'taglist', 'namedqueries',
                 'pyshell']
diff --git a/alot/ui.py b/alot/ui.py
index 013b4e7a..b528518f 100644
--- a/alot/ui.py
+++ b/alot/ui.py
@@ -115,7 +115,7 @@ class UI(object):
         self.mainloop = urwid.MainLoop(
             self.root_widget,
             handle_mouse=settings.get('handle_mouse'),
-            event_loop=urwid.AsyncioEventLoop(),
+            event_loop=urwid.TwistedEventLoop(),
             unhandled_input=self._unhandled_input,
             input_filter=self._input_filter)
 
diff --git a/setup.py b/setup.py
index 9c85a663..6c322404 100755
--- a/setup.py
+++ b/setup.py
@@ -48,6 +48,7 @@ setup(
         'notmuch>=0.26',
         'urwid>=1.3.0',
         'urwidtrees>=1.0',
+        'twisted>=10.2.0',
         'python-magic',
         'configobj>=4.7.0',
         'gpg'