make sure patch.dict() can be applied on async functions

Code is from gh#python/cpython@88b101f, it was released
upstream in 3.10.9.

Fixes: gh#python#98086
Patch: 99366-patch.dict-can-decorate-async.patch

Author: mcepl

Lib/unittest/mock.py

@@ -1595,6 +1595,12 @@ def __init__(self, in_dict, values=(), clear=False, **kwargs):
     def __call__(self, f):
         if isinstance(f, type):
             return self.decorate_class(f)
+        if inspect.iscoroutinefunction(f):
+            return self.decorate_async_callable(f)
+        return self.decorate_callable(f)
+
+
+    def decorate_callable(self, f):
         @wraps(f)
         def _inner(*args, **kw):
             self._patch_dict()
@@ -1606,6 +1612,18 @@ def _inner(*args, **kw):
         return _inner
 
 
+    def decorate_async_callable(self, f):
+        @wraps(f)
+        async def _inner(*args, **kw):
+            self._patch_dict()
+            try:
+                return await f(*args, **kw)
+            finally:
+                self._unpatch_dict()
+
+        return _inner
+
+
     def decorate_class(self, klass):
         for attr in dir(klass):
             attr_value = getattr(klass, attr)

Misc/NEWS.d/next/Library/2022-10-08-19-39-27.gh-issue-98086.y---WC.rst

@@ -0,0 +1 @@
+Make sure ``patch.dict()`` can be applied on async functions.