_get_running_loop: Support real asyncio.run

When called via the real asyncio.run implementation, wrap
the running asyncio loop. Otherwise, it's not possible to
call portage libraries via the real asyncio.run without
triggering Future "attached to a different loop" errors.

Bug: https://bugs.gentoo.org/761538
Signed-off-by: Zac Medico <zmedico@gentoo.org>

1 files changed, 26 insertions, 2 deletions

diff --git a/lib/portage/util/futures/_asyncio/__init__.py b/lib/portage/util/futures/_asyncio/__init__.py
index 22241f335..4eecc46a8 100644
--- a/lib/portage/util/futures/_asyncio/__init__.py
+++ b/lib/portage/util/futures/_asyncio/__init__.py
@@ -325,13 +325,37 @@ def _safe_loop():
 
 
 def _get_running_loop():
+    """
+    This calls the real asyncio get_running_loop() and wraps that with
+    portage's internal AsyncioEventLoop wrapper. If there is no running
+    asyncio event loop but portage has a reference to another running
+    loop in this thread, then use that instead.
+
+    This behavior enables portage internals to use the real asyncio.run
+    while remaining compatible with internal code that does not use the
+    real asyncio.run.
+    """
+    try:
+        _loop = _real_asyncio.get_running_loop()
+    except RuntimeError:
+        _loop = None
+
     with _thread_weakrefs.lock:
         if _thread_weakrefs.pid == portage.getpid():
             try:
                 loop = _thread_weakrefs.loops[threading.get_ident()]
             except KeyError:
-                return None
-            return loop if loop.is_running() else None
+                pass
+            else:
+                if _loop is loop._loop:
+                    return loop
+                elif _loop is None:
+                    return loop if loop.is_running() else None
+
+    # If _loop it not None here it means it was probably a temporary
+    # loop created by asyncio.run, so we don't try to cache it, and
+    # just return a temporary wrapper.
+    return None if _loop is None else _AsyncioEventLoop(loop=_loop)
 
 
 def _thread_weakrefs_atexit():