pylint issues resolved

Ran tests, and black afterwards. Updated changes.rst and included pre-commit hooks as required.  Ran isort on imports.

CHANGES.rst

@@ -7,7 +7,7 @@ Unreleased
 Version 2.2.3
 -------------
 
-Unreleased
+- tidy up of pylint issues across several files
 
 
 Version 2.2.2

examples/javascript/js_example/__init__.py

@@ -1,5 +1,5 @@
+from js_example import views  # noqa: F401
+
 from flask import Flask
 
 app = Flask(__name__)
-
-from js_example import views  # noqa: F401

examples/javascript/js_example/views.py

@@ -1,9 +1,7 @@
-from flask import jsonify
-from flask import render_template
-from flask import request
-
 from js_example import app
 
+from flask import jsonify, render_template, request
+
 
 @app.route("/", defaults={"js": "fetch"})
 @app.route("/<any(xhr, jquery, fetch):js>")

examples/javascript/tests/conftest.py

@@ -1,5 +1,4 @@
 import pytest
-
 from js_example import app
 
 

examples/javascript/tests/test_js_example.py

@@ -1,4 +1,5 @@
 import pytest
+
 from flask import template_rendered
 
 

examples/tutorial/flaskr/auth.py

@@ -1,17 +1,18 @@
 import functools
 
-from flask import Blueprint
-from flask import flash
-from flask import g
-from flask import redirect
-from flask import render_template
-from flask import request
-from flask import session
-from flask import url_for
-from werkzeug.security import check_password_hash
-from werkzeug.security import generate_password_hash
-
 from flaskr.db import get_db
+from werkzeug.security import check_password_hash, generate_password_hash
+
+from flask import (
+    Blueprint,
+    flash,
+    g,
+    redirect,
+    render_template,
+    request,
+    session,
+    url_for,
+)
 
 bp = Blueprint("auth", __name__, url_prefix="/auth")
 

examples/tutorial/flaskr/blog.py

@@ -1,14 +1,8 @@
-from flask import Blueprint
-from flask import flash
-from flask import g
-from flask import redirect
-from flask import render_template
-from flask import request
-from flask import url_for
-from werkzeug.exceptions import abort
-
 from flaskr.auth import login_required
 from flaskr.db import get_db
+from werkzeug.exceptions import abort
+
+from flask import Blueprint, flash, g, redirect, render_template, request, url_for
 
 bp = Blueprint("blog", __name__)
 

examples/tutorial/flaskr/db.py

@@ -1,8 +1,8 @@
 import sqlite3
 
 import click
-from flask import current_app
-from flask import g
+
+from flask import current_app, g
 
 
 def get_db():

examples/tutorial/tests/conftest.py

@@ -2,10 +2,8 @@ import os
 import tempfile
 
 import pytest
-
 from flaskr import create_app
-from flaskr.db import get_db
-from flaskr.db import init_db
+from flaskr.db import get_db, init_db
 
 # read in SQL for populating test data
 with open(os.path.join(os.path.dirname(__file__), "data.sql"), "rb") as f:

examples/tutorial/tests/test_auth.py

@@ -1,9 +1,8 @@
 import pytest
-from flask import g
-from flask import session
-
 from flaskr.db import get_db
 
+from flask import g, session
+
 
 def test_register(client, app):
     # test that viewing the page renders without template errors

examples/tutorial/tests/test_blog.py

@@ -1,5 +1,4 @@
 import pytest
-
 from flaskr.db import get_db
 
 

examples/tutorial/tests/test_db.py

@@ -1,7 +1,6 @@
 import sqlite3
 
 import pytest
-
 from flaskr.db import get_db
 
 

src/flask/__init__.py

@@ -1,46 +1,46 @@
 from markupsafe import escape
 from markupsafe import Markup
 
-from . import json as json
-from .app import Flask as Flask
-from .app import Request as Request
-from .app import Response as Response
-from .blueprints import Blueprint as Blueprint
-from .config import Config as Config
-from .ctx import after_this_request as after_this_request
-from .ctx import copy_current_request_context as copy_current_request_context
-from .ctx import has_app_context as has_app_context
-from .ctx import has_request_context as has_request_context
-from .globals import current_app as current_app
-from .globals import g as g
-from .globals import request as request
-from .globals import session as session
-from .helpers import abort as abort
-from .helpers import flash as flash
-from .helpers import get_flashed_messages as get_flashed_messages
-from .helpers import get_template_attribute as get_template_attribute
-from .helpers import make_response as make_response
-from .helpers import redirect as redirect
-from .helpers import send_file as send_file
-from .helpers import send_from_directory as send_from_directory
-from .helpers import stream_with_context as stream_with_context
-from .helpers import url_for as url_for
-from .json import jsonify as jsonify
-from .signals import appcontext_popped as appcontext_popped
-from .signals import appcontext_pushed as appcontext_pushed
-from .signals import appcontext_tearing_down as appcontext_tearing_down
-from .signals import before_render_template as before_render_template
-from .signals import got_request_exception as got_request_exception
-from .signals import message_flashed as message_flashed
-from .signals import request_finished as request_finished
-from .signals import request_started as request_started
-from .signals import request_tearing_down as request_tearing_down
-from .signals import signals_available as signals_available
-from .signals import template_rendered as template_rendered
-from .templating import render_template as render_template
-from .templating import render_template_string as render_template_string
-from .templating import stream_template as stream_template
-from .templating import stream_template_string as stream_template_string
+from . import json
+from .app import Flask
+from .app import Request
+from .app import Response
+from .blueprints import Blueprint
+from .config import Config
+from .ctx import after_this_request
+from .ctx import copy_current_request_context
+from .ctx import has_app_context
+from .ctx import has_request_context
+from .globals import current_app
+from .globals import g
+from .globals import request
+from .globals import session
+from .helpers import abort
+from .helpers import flash
+from .helpers import get_flashed_messages
+from .helpers import get_template_attribute
+from .helpers import make_response
+from .helpers import redirect
+from .helpers import send_file
+from .helpers import send_from_directory
+from .helpers import stream_with_context
+from .helpers import url_for
+from .json import jsonify
+from .signals import appcontext_popped
+from .signals import appcontext_pushed
+from .signals import appcontext_tearing_down
+from .signals import before_render_template
+from .signals import got_request_exception
+from .signals import message_flashed
+from .signals import request_finished
+from .signals import request_started
+from .signals import request_tearing_down
+from .signals import signals_available
+from .signals import template_rendered
+from .templating import render_template
+from .templating import render_template_string
+from .templating import stream_template
+from .templating import stream_template_string
 
 __version__ = "2.3.0.dev"
 
@@ -48,6 +48,7 @@ __version__ = "2.3.0.dev"
 def __getattr__(name):
     if name == "_app_ctx_stack":
         import warnings
+
         from .globals import __app_ctx_stack
 
         warnings.warn(
@@ -59,6 +60,7 @@ def __getattr__(name):
 
     if name == "_request_ctx_stack":
         import warnings
+
         from .globals import __request_ctx_stack
 
         warnings.warn(

src/flask/app.py

@@ -71,9 +71,9 @@ from .wrappers import Response
 
 if t.TYPE_CHECKING:  # pragma: no cover
     import typing_extensions as te
+
     from .blueprints import Blueprint
-    from .testing import FlaskClient
-    from .testing import FlaskCliRunner
+    from .testing import FlaskClient, FlaskCliRunner
 
 T_before_first_request = t.TypeVar(
     "T_before_first_request", bound=ft.BeforeFirstRequestCallable
@@ -866,7 +866,7 @@ class Flask(Scaffold):
                          subfolders use forward slashes as separator.
         :param mode: resource file opening mode, default is 'rb'.
         """
-        return open(os.path.join(self.instance_path, resource), mode)
+        return open(os.path.join(self.instance_path, resource), mode, encoding="utf-8")
 
     @property
     def templates_auto_reload(self) -> bool:

src/flask/cli.py

@@ -47,7 +47,7 @@ def find_best_app(module):
 
     if len(matches) == 1:
         return matches[0]
-    elif len(matches) > 1:
+    if len(matches) > 1:
         raise NoAppException(
             "Detected multiple Flask applications in module"
             f" '{module.__name__}'. Use '{module.__name__}:name'"
@@ -224,17 +224,15 @@ def locate_app(module_name, app_name, raise_if_not_found=True):
                 f"While importing {module_name!r}, an ImportError was"
                 f" raised:\n\n{traceback.format_exc()}"
             ) from None
-        elif raise_if_not_found:
+        if raise_if_not_found:
             raise NoAppException(f"Could not import {module_name!r}.") from None
-        else:
-            return
+        return
 
     module = sys.modules[module_name]
 
     if app_name is None:
         return find_best_app(module)
-    else:
-        return find_app_by_string(module, app_name)
+    return find_app_by_string(module, app_name)
 
 
 def get_version(ctx, param, value):
@@ -242,6 +240,7 @@ def get_version(ctx, param, value):
         return
 
     import werkzeug
+
     from . import __version__
 
     click.echo(
@@ -956,7 +955,7 @@ def shell_command() -> None:
     # is using it.
     startup = os.environ.get("PYTHONSTARTUP")
     if startup and os.path.isfile(startup):
-        with open(startup) as f:
+        with open(startup, encoding="utf-8") as f:
             eval(compile(f.read(), startup, "exec"), ctx)
 
     ctx.update(current_app.make_shell_context())

src/flask/config.py

@@ -261,7 +261,7 @@ class Config(dict):
         filename = os.path.join(self.root_path, filename)
 
         try:
-            with open(filename) as f:
+            with open(filename, encoding="utf-8") as f:
                 obj = load(f)
         except OSError as e:
             if silent and e.errno in (errno.ENOENT, errno.EISDIR):

src/flask/ctx.py

@@ -82,8 +82,7 @@ class _AppCtxGlobals:
         """
         if default is _sentinel:
             return self.__dict__.pop(name)
-        else:
-            return self.__dict__.pop(name, default)
+        return self.__dict__.pop(name, default)
 
     def setdefault(self, name: str, default: t.Any = None) -> t.Any:
         """Get the value of an attribute if it is present, otherwise

src/flask/debughelpers.py

@@ -106,7 +106,7 @@ def _dump_loader_info(loader) -> t.Generator:
             for item in value:
                 yield f"  - {item}"
             continue
-        elif not isinstance(value, (str, int, float, bool)):
+        if not isinstance(value, (str, int, float, bool)):
             continue
         yield f"{key}: {value!r}"
 

src/flask/globals.py

@@ -5,9 +5,7 @@ from werkzeug.local import LocalProxy
 
 if t.TYPE_CHECKING:  # pragma: no cover
     from .app import Flask
-    from .ctx import _AppCtxGlobals
-    from .ctx import AppContext
-    from .ctx import RequestContext
+    from .ctx import AppContext, RequestContext, _AppCtxGlobals
     from .sessions import SessionMixin
     from .wrappers import Request
 

src/flask/helpers.py

@@ -20,9 +20,10 @@ from .globals import session
 from .signals import message_flashed
 
 if t.TYPE_CHECKING:  # pragma: no cover
-    from werkzeug.wrappers import Response as BaseResponse
-    from .wrappers import Response
     import typing_extensions as te
+    from werkzeug.wrappers import Response as BaseResponse
+
+    from .wrappers import Response
 
 
 def get_env() -> str:

src/flask/scaffold.py

@@ -249,8 +249,7 @@ class Scaffold:
         """
         if self._static_folder is not None:
             return os.path.join(self.root_path, self._static_folder)
-        else:
-            return None
+        return None
 
     @static_folder.setter
     def static_folder(self, value: t.Optional[t.Union[str, os.PathLike]]) -> None:
@@ -342,8 +341,7 @@ class Scaffold:
         """
         if self.template_folder is not None:
             return FileSystemLoader(os.path.join(self.root_path, self.template_folder))
-        else:
-            return None
+        return None
 
     def open_resource(self, resource: str, mode: str = "rb") -> t.IO[t.AnyStr]:
         """Open a resource file relative to :attr:`root_path` for
@@ -366,7 +364,7 @@ class Scaffold:
         if mode not in {"r", "rt", "rb"}:
             raise ValueError("Resources can only be opened for reading.")
 
-        return open(os.path.join(self.root_path, resource), mode)
+        return open(os.path.join(self.root_path, resource), mode, encoding="utf-8")
 
     def _method_route(
         self,
@@ -743,8 +741,7 @@ class Scaffold:
 
         if issubclass(exc_class, HTTPException):
             return exc_class, exc_class.code
-        else:
-            return exc_class, None
+        return exc_class, None
 
 
 def _endpoint_from_view_func(view_func: t.Callable) -> str:
@@ -824,11 +821,10 @@ def _find_package_path(import_name):
                 search_locations = iter(root_spec.submodule_search_locations)
             return os.path.dirname(next(search_locations))
         # a package (with __init__.py)
-        elif root_spec.submodule_search_locations:
+        if root_spec.submodule_search_locations:
             return os.path.dirname(os.path.dirname(root_spec.origin))
         # just a normal module
-        else:
-            return os.path.dirname(root_spec.origin)
+        return os.path.dirname(root_spec.origin)
 
     # we were unable to find the `package_path` using PEP 451 loaders
     loader = pkgutil.get_loader(root_mod_name)

src/flask/sessions.py

@@ -14,6 +14,7 @@ from .json.tag import TaggedJSONSerializer
 
 if t.TYPE_CHECKING:  # pragma: no cover
     import typing_extensions as te
+
     from .app import Flask
     from .wrappers import Request, Response
 

src/flask/views.py

@@ -4,7 +4,6 @@ from . import typing as ft
 from .globals import current_app
 from .globals import request
 
-
 http_method_funcs = frozenset(
     ["get", "post", "head", "options", "delete", "put", "trace", "patch"]
 )

src/flask/wrappers.py

@@ -54,8 +54,7 @@ class Request(RequestBase):
         """Read-only view of the ``MAX_CONTENT_LENGTH`` config key."""
         if current_app:
             return current_app.config["MAX_CONTENT_LENGTH"]
-        else:
-            return None
+        return None
 
     @property
     def endpoint(self) -> t.Optional[str]:

tests/conftest.py

@@ -95,7 +95,7 @@ def leak_detector():
         leaks.append(request_ctx._get_current_object())
         request_ctx.pop()
 
-    assert leaks == []
+    assert not leaks
 
 
 @pytest.fixture(params=(True, False))

tests/test_apps/blueprintapp/__init__.py

@@ -1,9 +1,11 @@
+from blueprintapp.apps.admin import admin
+from blueprintapp.apps.frontend import frontend
+
 from flask import Flask
 
 app = Flask(__name__)
 app.config["DEBUG"] = True
-from blueprintapp.apps.admin import admin
-from blueprintapp.apps.frontend import frontend
+
 
 app.register_blueprint(admin)
 app.register_blueprint(frontend)

tests/test_apps/subdomaintestmodule/__init__.py

@@ -1,4 +1,3 @@
 from flask import Module
 
-
 mod = Module(__name__, "foo", subdomain="foo")

tests/test_basic.py

@@ -20,7 +20,6 @@ from werkzeug.routing import RequestRedirect
 
 import flask
 
-
 require_cpython_gc = pytest.mark.skipif(
     python_implementation() != "CPython",
     reason="Requires CPython GC behavior",
@@ -191,7 +190,7 @@ def test_url_mapping(app, client):
 
 
 def test_werkzeug_routing(app, client):
-    from werkzeug.routing import Submount, Rule
+    from werkzeug.routing import Rule, Submount
 
     app.url_map.add(
         Submount("/foo", [Rule("/bar", endpoint="bar"), Rule("/", endpoint="index")])
@@ -211,7 +210,7 @@ def test_werkzeug_routing(app, client):
 
 
 def test_endpoint_decorator(app, client):
-    from werkzeug.routing import Submount, Rule
+    from werkzeug.routing import Rule, Submount
 
     app.url_map.add(
         Submount("/foo", [Rule("/bar", endpoint="bar"), Rule("/", endpoint="index")])
@@ -486,9 +485,9 @@ def test_session_special_types(app, client):
         client.get("/")
         s = flask.session
         assert s["t"] == (1, 2, 3)
-        assert type(s["b"]) == bytes
+        assert isinstance(s["b"], bytes)
         assert s["b"] == b"\xff"
-        assert type(s["m"]) == flask.Markup
+        assert isinstance(s["m"], flask.Markup)
         assert s["m"] == flask.Markup("<html>")
         assert s["u"] == the_uuid
         assert s["d"] == now
@@ -792,7 +791,7 @@ def test_teardown_request_handler_error(app, client):
 
     @app.teardown_request
     def teardown_request1(exc):
-        assert type(exc) == ZeroDivisionError
+        assert isinstance(exc, ZeroDivisionError)
         called.append(True)
         # This raises a new error and blows away sys.exc_info(), so we can
         # test that all teardown_requests get passed the same original
@@ -804,7 +803,7 @@ def test_teardown_request_handler_error(app, client):
 
     @app.teardown_request
     def teardown_request2(exc):
-        assert type(exc) == ZeroDivisionError
+        assert isinstance(exc, ZeroDivisionError)
         called.append(True)
         # This raises a new error and blows away sys.exc_info(), so we can
         # test that all teardown_requests get passed the same original
@@ -1631,7 +1630,7 @@ def test_inject_blueprint_url_defaults(app):
 
     app.register_blueprint(bp)
 
-    values = dict()
+    values = {}
     app.inject_url_defaults("foo.view", values)
     expected = dict(page="login")
     assert values == expected

tests/test_blueprints.py

@@ -712,7 +712,7 @@ def test_request_processing(app, client):
 
     app.register_blueprint(bp)
 
-    assert evts == []
+    assert not evts
     rv = client.get("/bp")
     assert rv.data == b"request|after"
     assert evts == ["before", "after", "teardown"]
@@ -750,7 +750,7 @@ def test_app_request_processing(app, client):
         return "request"
 
     # before first request
-    assert evts == []
+    assert not evts
 
     # first request
     resp = client.get("/").data

tests/test_cli.py

@@ -227,10 +227,12 @@ def test_locate_app_suppress_raise(test_apps):
 
 
 def test_get_version(test_apps, capsys):
-    from flask import __version__ as flask_version
-    from werkzeug import __version__ as werkzeug_version
     from platform import python_version
 
+    from werkzeug import __version__ as werkzeug_version
+
+    from flask import __version__ as flask_version
+
     class MockCtx:
         resilient_parsing = False
         color = None

tests/test_config.py

@@ -6,7 +6,6 @@ import pytest
 
 import flask
 
-
 # config keys used for the TestConfig
 TEST_KEY = "foo"
 SECRET_KEY = "config"

tests/test_reqctx.py

@@ -22,7 +22,7 @@ def test_teardown_on_pop(app):
 
     ctx = app.test_request_context()
     ctx.push()
-    assert buffer == []
+    assert not buffer
     ctx.pop()
     assert buffer == [None]
 
@@ -40,7 +40,7 @@ def test_teardown_with_previous_exception(app):
         pass
 
     with app.test_request_context():
-        assert buffer == []
+        assert not buffer
     assert buffer == [None]
 
 
@@ -52,7 +52,7 @@ def test_teardown_with_handled_exception(app):
         buffer.append(exception)
 
     with app.test_request_context():
-        assert buffer == []
+        assert not buffer
         try:
             raise Exception("dummy")
         except Exception:
@@ -234,8 +234,7 @@ def test_session_dynamic_cookie_name():
         def get_cookie_name(self, app):
             if flask.request.url.endswith("dynamic_cookie"):
                 return "dynamic_cookie_name"
-            else:
-                return super().get_cookie_name(app)
+            return super().get_cookie_name(app)
 
     class CustomFlask(flask.Flask):
         session_interface = PathAwareSessionInterface()