Update black, and run auto formatting over the codebase (#9381)

 - Update black version to the latest
 - Run black auto formatting over the codebase
    - Run autoformatting according to [`docs/code_style.md
`](https://github.com/matrix-org/synapse/blob/80d6dc9783aa80886a133756028984dbf8920168/docs/code_style.md)
 - Update `code_style.md` docs around installing black to use the correct version

4 files changed, 37 insertions, 28 deletions

diff --git a/synapse/push/bulk_push_rule_evaluator.py b/synapse/push/bulk_push_rule_evaluator.py
index 6317f22d3c..c016a83909 100644
--- a/synapse/push/bulk_push_rule_evaluator.py
+++ b/synapse/push/bulk_push_rule_evaluator.py
@@ -144,8 +144,7 @@ class BulkPushRuleEvaluator:
 
     @lru_cache()
     def _get_rules_for_room(self, room_id: str) -> "RulesForRoom":
-        """Get the current RulesForRoom object for the given room id
-        """
+        """Get the current RulesForRoom object for the given room id"""
         # It's important that RulesForRoom gets added to self._get_rules_for_room.cache
         # before any lookup methods get called on it as otherwise there may be
         # a race if invalidate_all gets called (which assumes its in the cache)
@@ -252,7 +251,9 @@ class BulkPushRuleEvaluator:
         # notified for this event. (This will then get handled when we persist
         # the event)
         await self.store.add_push_actions_to_staging(
-            event.event_id, actions_by_user, count_as_unread,
+            event.event_id,
+            actions_by_user,
+            count_as_unread,
         )
 
 
diff --git a/synapse/push/emailpusher.py b/synapse/push/emailpusher.py
index 4ac1b31748..5fec2aaf5d 100644
--- a/synapse/push/emailpusher.py
+++ b/synapse/push/emailpusher.py
@@ -116,8 +116,7 @@ class EmailPusher(Pusher):
         self._is_processing = True
 
     def _resume_processing(self) -> None:
-        """Used by tests to resume processing of events after pausing.
-        """
+        """Used by tests to resume processing of events after pausing."""
         assert self._is_processing
         self._is_processing = False
         self._start_processing()
@@ -157,8 +156,10 @@ class EmailPusher(Pusher):
         being run.
         """
         start = 0 if INCLUDE_ALL_UNREAD_NOTIFS else self.last_stream_ordering
-        unprocessed = await self.store.get_unread_push_actions_for_user_in_range_for_email(
-            self.user_id, start, self.max_stream_ordering
+        unprocessed = (
+            await self.store.get_unread_push_actions_for_user_in_range_for_email(
+                self.user_id, start, self.max_stream_ordering
+            )
         )
 
         soonest_due_at = None  # type: Optional[int]
@@ -222,12 +223,14 @@ class EmailPusher(Pusher):
         self, last_stream_ordering: int
     ) -> None:
         self.last_stream_ordering = last_stream_ordering
-        pusher_still_exists = await self.store.update_pusher_last_stream_ordering_and_success(
-            self.app_id,
-            self.email,
-            self.user_id,
-            last_stream_ordering,
-            self.clock.time_msec(),
+        pusher_still_exists = (
+            await self.store.update_pusher_last_stream_ordering_and_success(
+                self.app_id,
+                self.email,
+                self.user_id,
+                last_stream_ordering,
+                self.clock.time_msec(),
+            )
         )
         if not pusher_still_exists:
             # The pusher has been deleted while we were processing, so
@@ -298,7 +301,8 @@ class EmailPusher(Pusher):
                     current_throttle_ms * THROTTLE_MULTIPLIER, THROTTLE_MAX_MS
                 )
         self.throttle_params[room_id] = ThrottleParams(
-            self.clock.time_msec(), new_throttle_ms,
+            self.clock.time_msec(),
+            new_throttle_ms,
         )
         assert self.pusher_id is not None
         await self.store.set_throttle_params(
diff --git a/synapse/push/httppusher.py b/synapse/push/httppusher.py
index e048b0d59e..b9d3da2e0a 100644
--- a/synapse/push/httppusher.py
+++ b/synapse/push/httppusher.py
@@ -176,8 +176,10 @@ class HttpPusher(Pusher):
         Never call this directly: use _process which will only allow this to
         run once per pusher.
         """
-        unprocessed = await self.store.get_unread_push_actions_for_user_in_range_for_http(
-            self.user_id, self.last_stream_ordering, self.max_stream_ordering
+        unprocessed = (
+            await self.store.get_unread_push_actions_for_user_in_range_for_http(
+                self.user_id, self.last_stream_ordering, self.max_stream_ordering
+            )
         )
 
         logger.info(
@@ -204,12 +206,14 @@ class HttpPusher(Pusher):
                 http_push_processed_counter.inc()
                 self.backoff_delay = HttpPusher.INITIAL_BACKOFF_SEC
                 self.last_stream_ordering = push_action["stream_ordering"]
-                pusher_still_exists = await self.store.update_pusher_last_stream_ordering_and_success(
-                    self.app_id,
-                    self.pushkey,
-                    self.user_id,
-                    self.last_stream_ordering,
-                    self.clock.time_msec(),
+                pusher_still_exists = (
+                    await self.store.update_pusher_last_stream_ordering_and_success(
+                        self.app_id,
+                        self.pushkey,
+                        self.user_id,
+                        self.last_stream_ordering,
+                        self.clock.time_msec(),
+                    )
                 )
                 if not pusher_still_exists:
                     # The pusher has been deleted while we were processing, so
@@ -290,7 +294,8 @@ class HttpPusher(Pusher):
                     # for sanity, we only remove the pushkey if it
                     # was the one we actually sent...
                     logger.warning(
-                        ("Ignoring rejected pushkey %s because we didn't send it"), pk,
+                        ("Ignoring rejected pushkey %s because we didn't send it"),
+                        pk,
                     )
                 else:
                     logger.info("Pushkey %s was rejected: removing", pk)
diff --git a/synapse/push/pusherpool.py b/synapse/push/pusherpool.py
index eed16dbfb5..ae1145be0e 100644
--- a/synapse/push/pusherpool.py
+++ b/synapse/push/pusherpool.py
@@ -78,8 +78,7 @@ class PusherPool:
         self.pushers = {}  # type: Dict[str, Dict[str, Pusher]]
 
     def start(self) -> None:
-        """Starts the pushers off in a background process.
-        """
+        """Starts the pushers off in a background process."""
         if not self._should_start_pushers:
             logger.info("Not starting pushers because they are disabled in the config")
             return
@@ -297,8 +296,7 @@ class PusherPool:
         return pusher
 
     async def _start_pushers(self) -> None:
-        """Start all the pushers
-        """
+        """Start all the pushers"""
         pushers = await self.store.get_all_pushers()
 
         # Stagger starting up the pushers so we don't completely drown the
@@ -335,7 +333,8 @@ class PusherPool:
             return None
         except Exception:
             logger.exception(
-                "Couldn't start pusher id %i: caught Exception", pusher_config.id,
+                "Couldn't start pusher id %i: caught Exception",
+                pusher_config.id,
             )
             return None