Move async_cache into a separate module

2 files changed, 34 insertions, 31 deletions

diff --git a/bot/cogs/doc/cache.py b/bot/cogs/doc/cache.py
new file mode 100644
index 000000000..9da2a1dab
--- /dev/null
+++ b/bot/cogs/doc/cache.py
@@ -0,0 +1,32 @@
+import functools
+from collections import OrderedDict
+from typing import Any, Callable
+
+
+def async_cache(max_size: int = 128, arg_offset: int = 0) -> Callable:
+    """
+    LRU cache implementation for coroutines.
+
+    Once the cache exceeds the maximum size, keys are deleted in FIFO order.
+
+    An offset may be optionally provided to be applied to the coroutine's arguments when creating the cache key.
+    """
+    # Assign the cache to the function itself so we can clear it from outside.
+    async_cache.cache = OrderedDict()
+
+    def decorator(function: Callable) -> Callable:
+        """Define the async_cache decorator."""
+        @functools.wraps(function)
+        async def wrapper(*args) -> Any:
+            """Decorator wrapper for the caching logic."""
+            key = ':'.join(args[arg_offset:])
+
+            value = async_cache.cache.get(key)
+            if value is None:
+                if len(async_cache.cache) > max_size:
+                    async_cache.cache.popitem(last=False)
+
+                async_cache.cache[key] = await function(*args)
+            return async_cache.cache[key]
+        return wrapper
+    return decorator
diff --git a/bot/cogs/doc/cog.py b/bot/cogs/doc/cog.py
index 463e4ebc6..2627951e8 100644
--- a/bot/cogs/doc/cog.py
+++ b/bot/cogs/doc/cog.py
@@ -7,7 +7,7 @@ import textwrap
 from collections import OrderedDict
 from contextlib import suppress
 from types import SimpleNamespace
-from typing import Any, Callable, Dict, List, NamedTuple, Optional, Tuple, Union
+from typing import Callable, Dict, List, NamedTuple, Optional, Tuple, Union
 from urllib.parse import urljoin
 
 import discord
@@ -25,7 +25,7 @@ from bot.converters import PackageName, ValidURL
 from bot.decorators import with_role
 from bot.pagination import LinePaginator
 from bot.utils.messages import wait_for_deletion
-
+from .cache import async_cache
 
 log = logging.getLogger(__name__)
 logging.getLogger('urllib3').setLevel(logging.WARNING)
@@ -76,35 +76,6 @@ class DocItem(NamedTuple):
     group: str
 
 
-def async_cache(max_size: int = 128, arg_offset: int = 0) -> Callable:
-    """
-    LRU cache implementation for coroutines.
-
-    Once the cache exceeds the maximum size, keys are deleted in FIFO order.
-
-    An offset may be optionally provided to be applied to the coroutine's arguments when creating the cache key.
-    """
-    # Assign the cache to the function itself so we can clear it from outside.
-    async_cache.cache = OrderedDict()
-
-    def decorator(function: Callable) -> Callable:
-        """Define the async_cache decorator."""
-        @functools.wraps(function)
-        async def wrapper(*args) -> Any:
-            """Decorator wrapper for the caching logic."""
-            key = ':'.join(args[arg_offset:])
-
-            value = async_cache.cache.get(key)
-            if value is None:
-                if len(async_cache.cache) > max_size:
-                    async_cache.cache.popitem(last=False)
-
-                async_cache.cache[key] = await function(*args)
-            return async_cache.cache[key]
-        return wrapper
-    return decorator
-
-
 class DocMarkdownConverter(MarkdownConverter):
     """Subclass markdownify's MarkdownCoverter to provide custom conversion methods."""