From faffc8eeb2ca06cae60b726fa873e474a51ac39b Mon Sep 17 00:00:00 2001
From: Dan Hess <danielman0@yahoo.com>
Date: Sat, 26 Dec 2020 19:58:58 -0600
Subject: [PATCH] [commands] Correct concurrency never releasing during prepare
 call

---
 discord/ext/commands/core.py | 19 ++++++++++++-------
 1 file changed, 12 insertions(+), 7 deletions(-)

diff --git a/discord/ext/commands/core.py b/discord/ext/commands/core.py
index 4f36ab9a9..248a0e143 100644
--- a/discord/ext/commands/core.py
+++ b/discord/ext/commands/core.py
@@ -781,14 +781,19 @@ class Command(_BaseCommand):
         if self._max_concurrency is not None:
             await self._max_concurrency.acquire(ctx)
 
-        if self.cooldown_after_parsing:
-            await self._parse_arguments(ctx)
-            self._prepare_cooldowns(ctx)
-        else:
-            self._prepare_cooldowns(ctx)
-            await self._parse_arguments(ctx)
+        try:
+            if self.cooldown_after_parsing:
+                await self._parse_arguments(ctx)
+                self._prepare_cooldowns(ctx)
+            else:
+                self._prepare_cooldowns(ctx)
+                await self._parse_arguments(ctx)
 
-        await self.call_before_hooks(ctx)
+            await self.call_before_hooks(ctx)
+        except:
+            if self._max_concurrency is not None:
+                await self._max_concurrency.release(ctx)
+            raise
 
     def is_on_cooldown(self, ctx):
         """Checks whether the command is currently on cooldown.