1 files changed, 7 insertions, 7 deletions
diff --git a/synapse/util/caches/deferred_cache.py b/synapse/util/caches/deferred_cache.py
index b6456392cd..f05590da0d 100644
--- a/synapse/util/caches/deferred_cache.py
+++ b/synapse/util/caches/deferred_cache.py
@@ -93,7 +93,7 @@ class DeferredCache(Generic[KT, VT]):
             TreeCache, "MutableMapping[KT, CacheEntry]"
         ] = cache_type()
 
-        def metrics_cb():
+        def metrics_cb() -> None:
             cache_pending_metric.labels(name).set(len(self._pending_deferred_cache))
 
         # cache is used for completed results and maps to the result itself, rather than
@@ -113,7 +113,7 @@ class DeferredCache(Generic[KT, VT]):
     def max_entries(self):
         return self.cache.max_size
 
-    def check_thread(self):
+    def check_thread(self) -> None:
         expected_thread = self.thread
         if expected_thread is None:
             self.thread = threading.current_thread()
@@ -235,7 +235,7 @@ class DeferredCache(Generic[KT, VT]):
 
         self._pending_deferred_cache[key] = entry
 
-        def compare_and_pop():
+        def compare_and_pop() -> bool:
             """Check if our entry is still the one in _pending_deferred_cache, and
             if so, pop it.
 
@@ -256,7 +256,7 @@ class DeferredCache(Generic[KT, VT]):
 
             return False
 
-        def cb(result):
+        def cb(result) -> None:
             if compare_and_pop():
                 self.cache.set(key, result, entry.callbacks)
             else:
@@ -268,7 +268,7 @@ class DeferredCache(Generic[KT, VT]):
                 # not have been. Either way, let's double-check now.
                 entry.invalidate()
 
-        def eb(_fail):
+        def eb(_fail) -> None:
             compare_and_pop()
             entry.invalidate()
 
@@ -314,7 +314,7 @@ class DeferredCache(Generic[KT, VT]):
             for entry in iterate_tree_cache_entry(entry):
                 entry.invalidate()
 
-    def invalidate_all(self):
+    def invalidate_all(self) -> None:
         self.check_thread()
         self.cache.clear()
         for entry in self._pending_deferred_cache.values():
@@ -332,7 +332,7 @@ class CacheEntry:
         self.callbacks = set(callbacks)
         self.invalidated = False
 
-    def invalidate(self):
+    def invalidate(self) -> None:
         if not self.invalidated:
             self.invalidated = True
             for callback in self.callbacks: