Drop user supplied loop (#2531)

* Drop user supplied loop

* Fix failed tests

* Drop unused imports

* Fix flake

aiohttp/web.py

@@ -1,8 +1,6 @@
 import asyncio
-import os
 import signal
 import socket
-import stat
 import sys
 import warnings
 from argparse import ArgumentParser
@@ -376,15 +374,6 @@ def _make_server_creators(handler, *, loop, ssl_context,
         )
         uris.append('{}://unix:{}:'.format(scheme, path))
 
-        # Clean up prior socket path if stale and not abstract.
-        # CPython 3.5.3+'s event loop already does this. See
-        # https://github.com/python/asyncio/issues/425
-        if path[0] not in (0, '\x00'):  # pragma: no branch
-            try:
-                if stat.S_ISSOCK(os.stat(path).st_mode):
-                    os.remove(path)
-            except FileNotFoundError:
-                pass
     for sock in socks:
         server_creations.append(
             loop.create_server(
@@ -403,11 +392,9 @@ def _make_server_creators(handler, *, loop, ssl_context,
 def run_app(app, *, host=None, port=None, path=None, sock=None,
             shutdown_timeout=60.0, ssl_context=None,
             print=print, backlog=128, access_log_format=None,
-            access_log=access_logger, handle_signals=True, loop=None):
+            access_log=access_logger, handle_signals=True):
     """Run an app locally"""
-    user_supplied_loop = loop is not None
-    if loop is None:
-        loop = asyncio.get_event_loop()
+    loop = asyncio.get_event_loop()
 
     app._set_loop(loop)
     app.freeze()
@@ -455,10 +442,9 @@ def run_app(app, *, host=None, port=None, path=None, sock=None,
             loop.run_until_complete(handler.shutdown(shutdown_timeout))
     finally:
         loop.run_until_complete(app.cleanup())
-    if not user_supplied_loop:
-        if hasattr(loop, 'shutdown_asyncgens'):
-            loop.run_until_complete(loop.shutdown_asyncgens())
-        loop.close()
+    if hasattr(loop, 'shutdown_asyncgens'):
+        loop.run_until_complete(loop.shutdown_asyncgens())
+    loop.close()
 
 
 def main(argv):

docs/web_reference.rst

@@ -2246,7 +2246,7 @@ Utilities
                       ssl_context=None, print=print, backlog=128, \
                       access_log_format=None, \
                       access_log=aiohttp.log.access_logger, \
-                      handle_signals=True, loop=None)
+                      handle_signals=True)
 
    A utility function for running an application, serving it until
    keyboard interrupt and performing a
@@ -2256,8 +2256,6 @@ Utilities
    Perhaps production config will use more sophisticated runner but it
    good enough at least at very beginning stage.
 
-   The function uses *app.loop* as event loop to run.
-
    The server will listen on any host or Unix domain socket path you supply.
    If no hosts or paths are supplied, or only a port is supplied, a TCP server
    listening on 0.0.0.0 (all hosts) will be launched.
@@ -2317,13 +2315,6 @@ Utilities
    :param bool handle_signals: override signal TERM handling to gracefully
                                exit the application.
 
-   :param loop: an *event loop* used for running the application
-                (``None`` by default).
-
-                If the loop is not explicitly specified the function
-                closes it by :meth:`~asyncio.AbstractEventLoop.close` call but
-                **does nothing** for **non-default** loop.
-
 
 Constants
 ---------