mypy: Various strict-optional fixes in zerver.

zerver/lib/bugdown/__init__.py

@@ -67,7 +67,7 @@ class BugdownRenderingException(Exception):
 def url_embed_preview_enabled_for_realm(message):
     # type: (Optional[Message]) -> bool
     if message is not None:
-        realm = message.get_realm()
+        realm = message.get_realm() # type: Optional[Realm]
     else:
         realm = None
 
@@ -81,7 +81,7 @@ def image_preview_enabled_for_realm():
     # type: () -> bool
     global current_message
     if current_message is not None:
-        realm = current_message.get_realm()
+        realm = current_message.get_realm() # type: Optional[Realm]
     else:
         realm = None
     if not settings.INLINE_IMAGE_PREVIEW:
@@ -1457,7 +1457,7 @@ def do_convert(content, message=None, message_realm=None, possible_words=None, s
     # * Nothing is passed in other than content -> just run default options (e.g. for docs)
     # * message is passed, but no realm is -> look up realm from message
     # * message_realm is passed -> use that realm for bugdown purposes
-    if message:
+    if message is not None:
         if message_realm is None:
             message_realm = message.get_realm()
     if message_realm is None:
@@ -1488,7 +1488,8 @@ def do_convert(content, message=None, message_realm=None, possible_words=None, s
 
     # Pre-fetch data from the DB that is used in the bugdown thread
     global db_data
-    if message:
+    if message is not None:
+        assert message_realm is not None # ensured above if message is not None
         realm_users = get_active_user_dicts_in_realm(message_realm)
         realm_streams = get_active_streams(message_realm).values('id', 'name')
 

zerver/lib/notifications.py

@@ -132,6 +132,7 @@ def build_message_list(user_profile, messages):
         plain = fix_plaintext_image_urls(plain)
         plain = relative_to_full_url(plain)
 
+        assert message.rendered_content is not None
         html = message.rendered_content
         html = relative_to_full_url(html)
         html = fix_emoji_sizes(html)

zerver/lib/timeout.py

@@ -42,7 +42,7 @@ def timeout(timeout, func, *args, **kwargs):
             # type: () -> None
             threading.Thread.__init__(self)
             self.result = None  # type: Optional[ResultT]
-            self.exc_info = None  # type: Optional[Tuple[Type[BaseException], BaseException, TracebackType]]
+            self.exc_info = None  # type: Optional[Tuple[Optional[Type[BaseException]], Optional[BaseException], Optional[TracebackType]]]
 
             # Don't block the whole program from exiting
             # if this is the only thread left.
@@ -92,4 +92,5 @@ def timeout(timeout, func, *args, **kwargs):
         # Raise the original stack trace so our error messages are more useful.
         # from http://stackoverflow.com/a/4785766/90777
         six.reraise(thread.exc_info[0], thread.exc_info[1], thread.exc_info[2])
+    assert thread.result is not None # assured if above did not reraise
     return thread.result

zerver/lib/upload.py

@@ -228,7 +228,9 @@ def get_file_info(request, user_file):
         if guessed_type is not None:
             content_type = force_text(guessed_type)
     else:
-        uploaded_file_name = uploaded_file_name + guess_extension(content_type)
+        extension = guess_extension(content_type)
+        if extension is not None:
+            uploaded_file_name = uploaded_file_name + extension
 
     uploaded_file_name = urllib.parse.unquote(uploaded_file_name)
     uploaded_file_size = user_file.size

zerver/models.py

@@ -963,7 +963,7 @@ def get_stream_backend(stream_name, realm):
         name__iexact=stream_name.strip(), realm_id=realm.id)
 
 def get_active_streams(realm):
-    # type: (Realm) -> QuerySet
+    # type: (Optional[Realm]) -> QuerySet
     """
     Return all streams (including invite-only streams) that have not been deactivated.
     """