From 40369a493d0fc9b948dda7679e08a06fc85511ad Mon Sep 17 00:00:00 2001
From: Josh B <josh.ja.butt@gmail.com>
Date: Tue, 21 Jan 2020 15:53:53 +1000
Subject: [PATCH] Add discord.utils.sleep_until helper function

---
 discord/utils.py | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/discord/utils.py b/discord/utils.py
index 83fdda2aa..53eccf82f 100644
--- a/discord/utils.py
+++ b/discord/utils.py
@@ -338,6 +338,24 @@ async def sane_wait_for(futures, *, timeout):
 
     return done
 
+async def sleep_until(when):
+    """Sleep until a specified time.
+
+    If the time supplied is in the past this function will yield instantly.
+    
+    Parameters
+    -----------
+    when: :class:`datetime.datetime`
+        The timestamp in which to sleep until.
+
+    .. versionadded:: 1.3.0
+    """
+    if when.tzinfo is None:
+        when = when.replace(tzinfo=datetime.timezone.utc)
+    now = datetime.datetime.now(datetime.timezone.utc)
+    delta = (when - now).total_seconds()
+    await asyncio.sleep(max(delta, 0))
+
 def valid_icon_size(size):
     """Icons must be power of 2 within [16, 4096]."""
     return not size & (size - 1) and size in range(16, 4097)