From: Miss Islington (bot) <31488909+miss-islington@users.noreply.github.com>
Date: Wed, 25 Sep 2019 09:12:47 +0000 (-0700)
Subject: bpo-38260: Add Docs on asyncio.run (GH-16337)
X-Git-Tag: v3.8.0rc1~43
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=4633355a063c7bf068bdd72dfdd32f4c22cf382f;p=python

bpo-38260: Add Docs on asyncio.run (GH-16337)


Add docs about return and raise exception on asyncio.run

https://bugs.python.org/issue38260

Automerge-Triggered-By: @asvetlov
(cherry picked from commit 17deb16883fa574a86e42551cc37f044182347ad)

Co-authored-by: Emmanuel Arias <emmanuelarias30@gmail.com>
---

diff --git a/Doc/library/asyncio-task.rst b/Doc/library/asyncio-task.rst
index 7efec5b6c1..321b4f4576 100644
--- a/Doc/library/asyncio-task.rst
+++ b/Doc/library/asyncio-task.rst
@@ -225,6 +225,18 @@ Running an asyncio Program
     the end.  It should be used as a main entry point for asyncio
     programs, and should ideally only be called once.
 
+    Return a result of *coro* execution, or raise a :exc:`RuntimeError`
+    if ``asyncio.run()`` is called from a running event loop, or a
+    :exc:`ValueError` if *coro* is not a courutine.
+
+    Example::
+
+        async def main():
+            await asyncio.sleep(1)
+            print('hello')
+
+        asyncio.run(main())
+
     .. versionadded:: 3.7
 
 
diff --git a/Lib/asyncio/runners.py b/Lib/asyncio/runners.py
index 5fbab03dd0..df686386b8 100644
--- a/Lib/asyncio/runners.py
+++ b/Lib/asyncio/runners.py
@@ -21,6 +21,10 @@ def run(main, *, debug=False):
     It should be used as a main entry point for asyncio programs, and should
     ideally only be called once.
 
+    Return a result of *coro* execution, or raise a RuntimeError
+    if `asyncio.run()`is called from a running event loop, or a ValueError
+    if `main` is not a courutine.
+
     Example:
 
         async def main():