Replace cast with typing

Author: T4rk1n

dash/_pages.py

@@ -8,7 +8,6 @@
 from pathlib import Path
 from os.path import isfile, join
 from urllib.parse import parse_qs, unquote
-from typing import cast
 
 import flask
 
@@ -87,8 +86,12 @@ def _infer_path(module_name, template):
 
 
 def _module_name_is_package(module_name):
-    file_path = cast(str, sys.modules[module_name].__file__)  # to satisfy type checking
-    return module_name in sys.modules and Path(file_path).name == "__init__.py"
+    file_path = sys.modules[module_name].__file__
+    return (
+        file_path
+        and module_name in sys.modules
+        and Path(file_path).name == "__init__.py"
+    )
 
 
 def _path_to_module_name(path):

dash/_utils.py

@@ -15,7 +15,7 @@
 
 from html import escape
 from functools import wraps
-from typing import Union, cast
+from typing import Union
 from .types import RendererHooks
 
 logger = logging.getLogger()
@@ -121,7 +121,7 @@ def __setitem__(self, key, val):
     def update(self, other=None, **kwargs):
         # Overrides dict.update() to use __setitem__ above
         # Needs default `None` and `kwargs` to satisfy type checking
-        source = cast(dict, other) if other is not None else kwargs
+        source = other if other is not None else kwargs
         for k, v in source.items():
             self[k] = v
 

dash/dash.py

@@ -18,7 +18,7 @@
 import base64
 import traceback
 from urllib.parse import urlparse
-from typing import Any, Callable, Dict, Optional, Union, Sequence, cast, Literal
+from typing import Any, Callable, Dict, Optional, Union, Sequence, Literal
 
 import flask
 
@@ -448,7 +448,6 @@ def __init__(  # pylint: disable=too-many-statements
             if name is None:
                 caller_name = getattr(server, "name", caller_name)
         elif isinstance(server, bool):
-            name = name if name else caller_name
             self.server = flask.Flask(caller_name) if server else None  # type: ignore
         else:
             raise ValueError("server must be a Flask app or a boolean")
@@ -457,7 +456,6 @@ def __init__(  # pylint: disable=too-many-statements
             url_base_pathname, routes_pathname_prefix, requests_pathname_prefix
         )
 
-        name = cast(str, name)  # to satisfy type checking
         self.config = AttributeDict(
             name=caller_name,
             assets_folder=os.path.join(
@@ -1788,7 +1786,7 @@ def enable_dev_tools(
         dev_tools_silence_routes_logging: Optional[bool] = None,
         dev_tools_disable_version_check: Optional[bool] = None,
         dev_tools_prune_errors: Optional[bool] = None,
-    ) -> None:
+    ) -> bool:
         """Activate the dev tools, called by `run`. If your application
         is served by wsgi and you want to activate the dev tools, you can call
         this method out of `__main__`.

dash/testing/application_runners.py

@@ -9,7 +9,6 @@
 import logging
 import inspect
 import ctypes
-from typing import cast
 
 import runpy
 import requests
@@ -354,11 +353,9 @@ def start(self, app, start_timeout=2, cwd=None):  # type: ignore[reportIncompati
             # app is a string chunk, we make a temporary folder to store app.R
             # and its relevant assets
             tmp_dir = "/tmp" if not self.is_windows else os.getenv("TEMP")
-            tmp_dir = cast(str, tmp_dir)  # to satisfy type checking
+            tmp_dir = str(tmp_dir)  # to satisfy type checking
             hex_id = uuid.uuid4().hex
-            self._tmp_app_path = cast(
-                str, os.path.join(tmp_dir, hex_id)
-            )  # to satisfy type checking
+            self._tmp_app_path = os.path.join(tmp_dir, hex_id)
             try:
                 os.mkdir(self.tmp_app_path)  # type: ignore[reportArgumentType]
             except OSError: