Merge pull request #5226 from mhils/cleanup

`pyupgrade --py38-plus`

docs/scripts/api-events.py

@@ -5,7 +5,6 @@ import textwrap
 from pathlib import Path
 from typing import List, Type
 
-import mitmproxy.addons.next_layer  # noqa
 from mitmproxy import hooks, log, addonmanager
 from mitmproxy.proxy import server_hooks, layer
 from mitmproxy.proxy.layers import http, modes, tcp, tls, websocket

examples/addons/commands-paths.py

@@ -21,7 +21,7 @@ class MyAddon:
                 totals[f.request.host] = totals.setdefault(f.request.host, 0) + 1
 
         with open(path, "w+") as fp:
-            for cnt, dom in sorted([(v, k) for (k, v) in totals.items()]):
+            for cnt, dom in sorted((v, k) for (k, v) in totals.items()):
                 fp.write(f"{cnt}: {dom}\n")
 
         ctx.log.alert("done")

examples/addons/io-write-flow-file.py

@@ -10,7 +10,7 @@ to multiple files in parallel.
 import random
 import sys
 from mitmproxy import io, http
-import typing  # noqa
+import typing
 
 
 class Writer:

examples/addons/websocket-inject-message.py

@@ -15,7 +15,7 @@ def websocket_message(flow: http.HTTPFlow):
     last_message = flow.websocket.messages[-1]
     if last_message.is_text and "secret" in last_message.text:
         last_message.drop()
-        ctx.master.commands.call("inject.websocket", flow, last_message.from_client, "ssssssh".encode())
+        ctx.master.commands.call("inject.websocket", flow, last_message.from_client, b"ssssssh")
 
 
 # Complex example: Schedule a periodic timer

examples/contrib/har_dump.py

@@ -13,7 +13,7 @@ import json
 import base64
 import zlib
 import os
-import typing  # noqa
+import typing
 
 from datetime import datetime
 from datetime import timezone

examples/contrib/ntlm_upstream_proxy.py

@@ -3,14 +3,15 @@ import binascii
 import socket
 import typing
 
+from ntlm_auth import gss_channel_bindings, ntlm
+
+from mitmproxy import addonmanager, http
 from mitmproxy import ctx
-from mitmproxy import http, addonmanager
 from mitmproxy.net.http import http1
-from mitmproxy.proxy import layer, commands
+from mitmproxy.proxy import commands, layer
 from mitmproxy.proxy.context import Context
 from mitmproxy.proxy.layers.http import HttpConnectUpstreamHook, HttpLayer, HttpStream
 from mitmproxy.proxy.layers.http._upstream_proxy import HttpUpstreamProxy
-from ntlm_auth import gss_channel_bindings, ntlm
 
 
 class NTLMUpstreamAuth:
@@ -148,7 +149,7 @@ class CustomNTLMContext:
         ntlm_compatibility: int = ctx.options.upstream_ntlm_compatibility
         username, password = tuple(auth.split(":"))
         workstation = socket.gethostname().upper()
-        ctx.log.debug('\nntlm context with the details: "{}\\{}", *****'.format(domain, username))
+        ctx.log.debug(f'\nntlm context with the details: "{domain}\\{username}", *****')
         self.ctx_log = ctx.log
         self.preferred_type = preferred_type
         self.ntlm_context = ntlm.NtlmContext(
@@ -163,7 +164,7 @@ class CustomNTLMContext:
         negotiate_message = self.ntlm_context.step()
         negotiate_message_base_64_in_bytes = base64.b64encode(negotiate_message)
         negotiate_message_base_64_ascii = negotiate_message_base_64_in_bytes.decode("ascii")
-        negotiate_message_base_64_final = u'%s %s' % (self.preferred_type, negotiate_message_base_64_ascii)
+        negotiate_message_base_64_final = f'{self.preferred_type} {negotiate_message_base_64_ascii}'
         self.ctx_log.debug(
             f'{self.preferred_type} Authentication, negotiate message: {negotiate_message_base_64_final}'
         )
@@ -174,11 +175,11 @@ class CustomNTLMContext:
         try:
             challenge_message_ascii_bytes = base64.b64decode(challenge_message, validate=True)
         except binascii.Error as err:
-            self.ctx_log.debug('{} Authentication fail with error {}'.format(self.preferred_type, err.__str__()))
+            self.ctx_log.debug(f'{self.preferred_type} Authentication fail with error {err.__str__()}')
             return False
         authenticate_message = self.ntlm_context.step(challenge_message_ascii_bytes)
-        negotiate_message_base_64 = u'%s %s' % (self.preferred_type,
-                                                base64.b64encode(authenticate_message).decode('ascii'))
+        negotiate_message_base_64 = '{} {}'.format(self.preferred_type,
+                                                   base64.b64encode(authenticate_message).decode('ascii'))
         self.ctx_log.debug(
             f'{self.preferred_type} Authentication, response to challenge message: {negotiate_message_base_64}'
         )

examples/contrib/sslstrip.py

@@ -4,7 +4,7 @@ https://moxie.org/software/sslstrip/
 """
 import re
 import urllib.parse
-import typing  # noqa
+import typing
 
 from mitmproxy import http
 

mitmproxy/addons/core.py

@@ -178,7 +178,7 @@ class Core:
                         req.url = val
                     except ValueError as e:
                         raise exceptions.CommandError(
-                            "URL {} is invalid: {}".format(repr(val), e)
+                            f"URL {repr(val)} is invalid: {e}"
                         ) from e
                 else:
                     self.rupdate = False
@@ -199,7 +199,7 @@ class Core:
                 updated.append(f)
 
         ctx.master.addons.trigger(hooks.UpdateHook(updated))
-        ctx.log.alert("Set {} on  {} flows.".format(attr, len(updated)))
+        ctx.log.alert(f"Set {attr} on  {len(updated)} flows.")
 
     @command.command("flow.decode")
     def decode(self, flows: typing.Sequence[flow.Flow], part: str) -> None:

mitmproxy/addons/eventstore.py

@@ -1,5 +1,5 @@
 import collections
-import typing  # noqa
+import typing
 
 import blinker
 

mitmproxy/addons/export.py

@@ -63,7 +63,7 @@ def curl_command(f: flow.Flow) -> str:
     server_addr = f.server_conn.peername[0] if f.server_conn.peername else None
 
     if ctx.options.export_preserve_original_ip and server_addr and request.pretty_host != server_addr:
-        resolve = "{}:{}:[{}]".format(request.pretty_host, request.port, server_addr)
+        resolve = f"{request.pretty_host}:{request.port}:[{server_addr}]"
         args.append("--resolve")
         args.append(resolve)
 

mitmproxy/addons/serverplayback.py

@@ -112,7 +112,7 @@ class ServerPlayback:
 
     @command.command("replay.server.count")
     def count(self) -> int:
-        return sum([len(i) for i in self.flowmap.values()])
+        return sum(len(i) for i in self.flowmap.values())
 
     def _hash(self, flow: http.HTTPFlow) -> typing.Hashable:
         """

mitmproxy/addons/stickycookie.py

@@ -1,6 +1,6 @@
 import collections
 from http import cookiejar
-from typing import List, Tuple, Dict, Optional  # noqa
+from typing import List, Tuple, Dict, Optional
 
 from mitmproxy import http, flowfilter, ctx, exceptions
 from mitmproxy.net.http import cookies

mitmproxy/command.py

@@ -265,11 +265,11 @@ class CommandManager:
         parts, _ = self.parse_partial(cmdstr)
         if not parts:
             raise exceptions.CommandError(f"Invalid command: {cmdstr!r}")
-        command_name, *args = [
+        command_name, *args = (
             unquote(part.value)
             for part in parts
             if part.type != mitmproxy.types.Space
-        ]
+        )
         return self.call_strings(command_name, args)
 
     def dump(self, out=sys.stdout) -> None:

mitmproxy/contentviews/css.py

@@ -67,4 +67,4 @@ if __name__ == "__main__":  # pragma: no cover
 
     t = time.time()
     x = beautify(data)
-    print("Beautifying vendor.css took {:.2}s".format(time.time() - t))
+    print(f"Beautifying vendor.css took {time.time() - t:.2}s")

mitmproxy/contentviews/graphql.py

@@ -20,7 +20,7 @@ def format_query_list(data: typing.List[typing.Any]):
     num_queries = len(data) - 1
     result = ""
     for i, op in enumerate(data):
-        result += "--- {i}/{num_queries}\n".format(i=i, num_queries=num_queries)
+        result += f"--- {i}/{num_queries}\n"
         result += format_graphql(op)
     return result
 

mitmproxy/contentviews/grpc.py

@@ -200,7 +200,7 @@ class ProtoParser:
             # read field key (tag and wire_type)
             offset, key = ProtoParser._read_base128le(wire_data[pos:])
             # casting raises exception for invalid WireTypes
-            wt = ProtoParser.WireTypes((key & 7))
+            wt = ProtoParser.WireTypes(key & 7)
             tag = (key >> 3)
             pos += offset
 
@@ -232,7 +232,7 @@ class ProtoParser:
                 wt == ProtoParser.WireTypes.group_start or
                 wt == ProtoParser.WireTypes.group_end
             ):
-                raise ValueError("deprecated field: {}".format(wt))
+                raise ValueError(f"deprecated field: {wt}")
             elif wt == ProtoParser.WireTypes.bit_32:
                 offset, val = ProtoParser._read_u32(wire_data[pos:])
                 pos += offset
@@ -735,8 +735,7 @@ class ProtoParser:
                     yield field_desc_dict
                 # add sub-fields of messages or packed fields
                 for f in decoded_val:
-                    for field_dict in f.gen_flat_decoded_field_dicts():
-                        yield field_dict
+                    yield from f.gen_flat_decoded_field_dicts()
             else:
                 field_desc_dict["val"] = decoded_val
                 yield field_desc_dict
@@ -767,8 +766,7 @@ class ProtoParser:
 
     def gen_flat_decoded_field_dicts(self) -> Generator[Dict, None, None]:
         for f in self.root_fields:
-            for field_dict in f.gen_flat_decoded_field_dicts():
-                yield field_dict
+            yield from f.gen_flat_decoded_field_dicts()
 
     def gen_str_rows(self) -> Generator[Tuple[str, ...], None, None]:
         for field_dict in self.gen_flat_decoded_field_dicts():
@@ -879,8 +877,7 @@ def hack_generator_to_list(generator_func):
 
 
 def format_pbuf(message: bytes, parser_options: ProtoParser.ParserOptions, rules: List[ProtoParser.ParserRule]):
-    for l in format_table(ProtoParser(data=message, parser_options=parser_options, rules=rules).gen_str_rows()):
-        yield l
+    yield from format_table(ProtoParser(data=message, parser_options=parser_options, rules=rules).gen_str_rows())
 
 
 def format_grpc(
@@ -895,12 +892,11 @@ def format_grpc(
             compression_scheme if compressed else compressed) + ')'
 
         yield [("text", headline)]
-        for l in format_pbuf(
+        yield from format_pbuf(
             message=pb_message,
             parser_options=parser_options,
             rules=rules
-        ):
-            yield l
+        )
 
 
 @dataclass

mitmproxy/contentviews/image/image_parser.py

@@ -3,10 +3,10 @@ import typing
 
 from kaitaistruct import KaitaiStream
 
-from mitmproxy.contrib.kaitaistruct import png
 from mitmproxy.contrib.kaitaistruct import gif
-from mitmproxy.contrib.kaitaistruct import jpeg
 from mitmproxy.contrib.kaitaistruct import ico
+from mitmproxy.contrib.kaitaistruct import jpeg
+from mitmproxy.contrib.kaitaistruct import png
 
 Metadata = typing.List[typing.Tuple[str, str]]
 
@@ -91,12 +91,13 @@ def parse_ico(data: bytes) -> Metadata:
     for i, image in enumerate(img.images):
         parts.append(
             (
-                'Image {}'.format(i + 1), "Size: {} x {}\n"
-                                          "{: >18}Bits per pixel: {}\n"
-                                          "{: >18}PNG: {}".format(256 if not image.width else image.width,
-                                                                  256 if not image.height else image.height,
-                                                                  '', image.bpp,
-                                                                  '', image.is_png)
+                f'Image {i + 1}',
+                "Size: {} x {}\n"
+                "{: >18}Bits per pixel: {}\n"
+                "{: >18}PNG: {}".format(256 if not image.width else image.width,
+                                        256 if not image.height else image.height,
+                                        '', image.bpp,
+                                        '', image.is_png)
             )
         )
 

mitmproxy/contentviews/raw.py

@@ -1,5 +1,3 @@
-from typing import List  # noqa
-
 from mitmproxy.utils import strutils
 from . import base
 

mitmproxy/flow.py

@@ -1,6 +1,6 @@
 import asyncio
 import time
-import typing  # noqa
+import typing
 import uuid
 
 from mitmproxy import connection

mitmproxy/flowfilter.py

@@ -376,7 +376,7 @@ class FSrc(_Rex):
     def __call__(self, f):
         if not f.client_conn or not f.client_conn.peername:
             return False
-        r = "{}:{}".format(f.client_conn.peername[0], f.client_conn.peername[1])
+        r = f"{f.client_conn.peername[0]}:{f.client_conn.peername[1]}"
         return f.client_conn.peername and self.re.search(r)
 
 
@@ -388,7 +388,7 @@ class FDst(_Rex):
     def __call__(self, f):
         if not f.server_conn or not f.server_conn.address:
             return False
-        r = "{}:{}".format(f.server_conn.address[0], f.server_conn.address[1])
+        r = f"{f.server_conn.address[0]}:{f.server_conn.address[1]}"
         return f.server_conn.address and self.re.search(r)
 
 

mitmproxy/http.py

@@ -510,7 +510,7 @@ class Message(serializable.Serializable):
         self.headers["content-encoding"] = encoding
         self.content = self.raw_content
         if "content-encoding" not in self.headers:
-            raise ValueError("Invalid content encoding {}".format(repr(encoding)))
+            raise ValueError(f"Invalid content encoding {repr(encoding)}")
 
     def json(self, **kwargs: Any) -> Any:
         """
@@ -1033,7 +1033,7 @@ class Response(Message):
             reason = reason.encode("ascii", "strict")
 
         if isinstance(content, str):
-            raise ValueError("Content must be bytes, not {}".format(type(content).__name__))
+            raise ValueError(f"Content must be bytes, not {type(content).__name__}")
         if not isinstance(headers, Headers):
             headers = Headers(headers)
         if trailers is not None and not isinstance(trailers, Headers):

mitmproxy/io/compat.py

@@ -6,7 +6,7 @@ v3.0.0dev) and versioning. Every change or migration gets a new flow file
 version number, this prevents issues with developer builds and snapshots.
 """
 import uuid
-from typing import Any, Dict, Mapping, Union  # noqa
+from typing import Any, Dict, Mapping, Union
 
 from mitmproxy import version
 from mitmproxy.utils import strutils

mitmproxy/io/tnetstring.py

@@ -146,7 +146,7 @@ def _rdumpq(q: collections.deque, size: int, value: TSerializable) -> int:
         write(span)
         return size + 1 + len(span)
     else:
-        raise ValueError("unserializable object: {} ({})".format(value, type(value)))
+        raise ValueError(f"unserializable object: {value} ({type(value)})")
 
 
 def loads(string: bytes) -> TSerializable:

mitmproxy/net/encoding.py

@@ -4,15 +4,14 @@ Utility functions for decoding response bodies.
 
 import codecs
 import collections
-from io import BytesIO
-
 import gzip
 import zlib
+from io import BytesIO
+from typing import Union, overload
+
 import brotli
 import zstandard as zstd
 
-from typing import Union, Optional, AnyStr, overload  # noqa
-
 # We have a shared single-element cache for encoding and decoding.
 # This is quite useful in practice, e.g.
 # flow.request.content = flow.request.content.replace(b"foo", b"bar")
@@ -39,7 +38,7 @@ def decode(encoded: bytes, encoding: str, errors: str = 'strict') -> Union[str,
 
 
 def decode(
-        encoded: Union[None, str, bytes], encoding: str, errors: str = 'strict'
+    encoded: Union[None, str, bytes], encoding: str, errors: str = 'strict'
 ) -> Union[None, str, bytes]:
     """
     Decode the given input object
@@ -56,10 +55,10 @@ def decode(
 
     global _cache
     cached = (
-            isinstance(encoded, bytes) and
-            _cache.encoded == encoded and
-            _cache.encoding == encoding and
-            _cache.errors == errors
+        isinstance(encoded, bytes) and
+        _cache.encoded == encoded and
+        _cache.encoding == encoding and
+        _cache.errors == errors
     )
     if cached:
         return _cache.decoded
@@ -113,10 +112,10 @@ def encode(decoded: Union[None, str, bytes], encoding, errors='strict') -> Union
 
     global _cache
     cached = (
-            isinstance(decoded, bytes) and
-            _cache.decoded == decoded and
-            _cache.encoding == encoding and
-            _cache.errors == errors
+        isinstance(decoded, bytes) and
+        _cache.decoded == decoded and
+        _cache.encoding == encoding and
+        _cache.errors == errors
     )
     if cached:
         return _cache.encoded

mitmproxy/proxy/layers/websocket.py

@@ -63,7 +63,7 @@ class WebsocketConnection(wsproto.Connection):
     frame_buf: List[bytes]
 
     def __init__(self, *args, conn: connection.Connection, **kwargs):
-        super(WebsocketConnection, self).__init__(*args, **kwargs)
+        super().__init__(*args, **kwargs)
         self.conn = conn
         self.frame_buf = [b""]
 

mitmproxy/proxy/server.py

@@ -153,7 +153,7 @@ class ConnectionHandler(metaclass=abc.ABCMeta):
             try:
                 command.connection.timestamp_start = time.time()
                 reader, writer = await asyncio.open_connection(*command.connection.address)
-            except (IOError, asyncio.CancelledError) as e:
+            except (OSError, asyncio.CancelledError) as e:
                 err = str(e)
                 if not err:  # str(CancelledError()) returns empty string.
                     err = "connection cancelled"

mitmproxy/tcp.py

@@ -55,7 +55,7 @@ class TCPFlow(flow.Flow):
     _stateobject_attributes["messages"] = List[TCPMessage]
 
     def __repr__(self):
-        return "<TCPFlow ({} messages)>".format(len(self.messages))
+        return f"<TCPFlow ({len(self.messages)} messages)>"
 
 
 __all__ = [

mitmproxy/tools/console/eventlog.py

@@ -46,7 +46,7 @@ class EventLog(urwid.ListBox, layoutwidget.LayoutWidget):
     def add_event(self, event_store, entry: log.LogEntry):
         if log.log_tier(self.master.options.console_eventlog_verbosity) < log.log_tier(entry.level):
             return
-        txt = "{}: {}".format(entry.level, str(entry.msg))
+        txt = f"{entry.level}: {str(entry.msg)}"
         if entry.level in ("error", "warn", "alert"):
             e = urwid.Text((entry.level, txt))
         else:

mitmproxy/tools/console/flowlist.py

@@ -2,7 +2,7 @@ import urwid
 
 from mitmproxy.tools.console import common
 from mitmproxy.tools.console import layoutwidget
-import mitmproxy.tools.console.master # noqa
+import mitmproxy.tools.console.master
 
 
 class FlowItem(urwid.WidgetWrap):

mitmproxy/tools/console/flowview.py

@@ -1,11 +1,11 @@
 import math
 import sys
 from functools import lru_cache
-from typing import Optional, Union  # noqa
+
+import urwid
 
 import mitmproxy.flow
-import mitmproxy.tools.console.master  # noqa
-import urwid
+import mitmproxy.tools.console.master
 from mitmproxy import contentviews
 from mitmproxy import ctx
 from mitmproxy import http

mitmproxy/tools/console/grideditor/__init__.py

@@ -1,2 +1,21 @@
-from .editors import *  # noqa
-from . import base  # noqa
+from . import base
+from .editors import CookieAttributeEditor, CookieEditor, DataViewer, OptionsEditor, PathEditor, QueryEditor, \
+    RequestHeaderEditor, \
+    RequestMultipartEditor, \
+    RequestUrlEncodedEditor, \
+    ResponseHeaderEditor, SetCookieEditor
+
+__all__ = [
+    "base",
+    "QueryEditor",
+    "RequestHeaderEditor",
+    "ResponseHeaderEditor",
+    "RequestMultipartEditor",
+    "RequestUrlEncodedEditor",
+    "PathEditor",
+    "CookieEditor",
+    "CookieAttributeEditor",
+    "SetCookieEditor",
+    "OptionsEditor",
+    "DataViewer",
+]

mitmproxy/tools/console/grideditor/base.py

@@ -8,7 +8,7 @@ from mitmproxy.utils import strutils
 from mitmproxy import exceptions
 from mitmproxy.tools.console import signals
 from mitmproxy.tools.console import layoutwidget
-import mitmproxy.tools.console.master # noqa
+import mitmproxy.tools.console.master
 
 
 def read_file(filename: str, escaped: bool) -> typing.AnyStr:

mitmproxy/tools/console/master.py

@@ -89,7 +89,7 @@ class ConsoleMaster(master.Master):
             signals.status_message.send(
                 message = (
                     entry.level,
-                    "{}: {}".format(entry.level.title(), str(entry.msg).lstrip())
+                    f"{entry.level.title()}: {str(entry.msg).lstrip()}"
                 ),
                 expire=5
             )

mitmproxy/tools/console/overlay.py

@@ -108,7 +108,7 @@ class Chooser(urwid.WidgetWrap, layoutwidget.LayoutWidget):
         self.master = master
         self.choices = choices
         self.callback = callback
-        choicewidth = max([len(i) for i in choices])
+        choicewidth = max(len(i) for i in choices)
         self.width = max(choicewidth, len(title)) + 7
 
         self.walker = ChooserListWalker(choices, current)

mitmproxy/tools/console/palettes.py

@@ -1,4 +1,4 @@
-import typing  # noqa
+import typing
 # Low-color themes should ONLY use the standard foreground and background
 # colours listed here:
 #

mitmproxy/tools/console/statusbar.py

@@ -3,7 +3,7 @@ from typing import Optional
 
 import urwid
 
-import mitmproxy.tools.console.master  # noqa
+import mitmproxy.tools.console.master
 from mitmproxy.tools.console import commandexecutor
 from mitmproxy.tools.console import common
 from mitmproxy.tools.console import signals

mitmproxy/tools/main.py

@@ -100,7 +100,7 @@ def run(
                 opts.update(**extra(args))
 
         except exceptions.OptionsError as e:
-            print("{}: {}".format(sys.argv[0], e), file=sys.stderr)
+            print(f"{sys.argv[0]}: {e}", file=sys.stderr)
             sys.exit(1)
 
         loop = asyncio.get_running_loop()

mitmproxy/tools/web/app.py

@@ -206,7 +206,7 @@ class RequestHandler(tornado.web.RequestHandler):
         try:
             return json.loads(self.request.body.decode())
         except Exception as e:
-            raise APIError(400, "Malformed JSON: {}".format(str(e)))
+            raise APIError(400, f"Malformed JSON: {str(e)}")
 
     @property
     def filecontents(self):

mitmproxy/utils/debug.py

@@ -20,7 +20,7 @@ def dump_system_info():
     data = [
         f"Mitmproxy: {mitmproxy_version}",
         f"Python:    {platform.python_version()}",
-        "OpenSSL:   {}".format(SSL.SSLeay_version(SSL.SSLEAY_VERSION).decode()),
+        f"OpenSSL:   {SSL.SSLeay_version(SSL.SSLEAY_VERSION).decode()}",
         f"Platform:  {platform.platform()}",
     ]
     return "\n".join(data)

mitmproxy/utils/human.py

@@ -31,7 +31,7 @@ def pretty_size(size: int) -> str:
     raise AssertionError
 
 
-@functools.lru_cache()
+@functools.lru_cache
 def parse_size(s: typing.Optional[str]) -> typing.Optional[int]:
     """
     Parse a size with an optional k/m/... suffix.
@@ -65,7 +65,7 @@ def pretty_duration(secs: typing.Optional[float]) -> str:
         if secs >= limit:
             return formatter.format(secs)
     # less than 1 sec
-    return "{:.0f}ms".format(secs * 1000)
+    return f"{secs * 1000:.0f}ms"
 
 
 def format_timestamp(s):
@@ -79,7 +79,7 @@ def format_timestamp_with_milli(s):
     return d.strftime("%Y-%m-%d %H:%M:%S.%f")[:-3]
 
 
-@functools.lru_cache()
+@functools.lru_cache
 def format_address(address: typing.Optional[tuple]) -> str:
     """
     This function accepts IPv4/IPv6 tuples and
@@ -90,12 +90,12 @@ def format_address(address: typing.Optional[tuple]) -> str:
     try:
         host = ipaddress.ip_address(address[0])
         if host.is_unspecified:
-            return "*:{}".format(address[1])
+            return f"*:{address[1]}"
         if isinstance(host, ipaddress.IPv4Address):
-            return "{}:{}".format(str(host), address[1])
+            return f"{str(host)}:{address[1]}"
         # If IPv6 is mapped to IPv4
         elif host.ipv4_mapped:
-            return "{}:{}".format(str(host.ipv4_mapped), address[1])
-        return "[{}]:{}".format(str(host), address[1])
+            return f"{str(host.ipv4_mapped)}:{address[1]}"
+        return f"[{str(host)}]:{address[1]}"
     except ValueError:
-        return "{}:{}".format(address[0], address[1])
+        return f"{address[0]}:{address[1]}"

mitmproxy/utils/strutils.py

@@ -22,7 +22,7 @@ def always_bytes(str_or_bytes: Union[None, str, bytes], *encode_args) -> Union[N
     elif isinstance(str_or_bytes, str):
         return str_or_bytes.encode(*encode_args)
     else:
-        raise TypeError("Expected str or bytes, but got {}.".format(type(str_or_bytes).__name__))
+        raise TypeError(f"Expected str or bytes, but got {type(str_or_bytes).__name__}.")
 
 
 @overload
@@ -45,7 +45,7 @@ def always_str(str_or_bytes: Union[None, str, bytes], *decode_args) -> Union[Non
     elif isinstance(str_or_bytes, bytes):
         return str_or_bytes.decode(*decode_args)
     else:
-        raise TypeError("Expected str or bytes, but got {}.".format(type(str_or_bytes).__name__))
+        raise TypeError(f"Expected str or bytes, but got {type(str_or_bytes).__name__}.")
 
 
 # Translate control characters to "safe" characters. This implementation
@@ -73,7 +73,7 @@ def escape_control_characters(text: str, keep_spacing=True) -> str:
         keep_spacing: If True, tabs and newlines will not be replaced.
     """
     if not isinstance(text, str):
-        raise ValueError("text type must be unicode but is {}".format(type(text).__name__))
+        raise ValueError(f"text type must be unicode but is {type(text).__name__}")
 
     trans = _control_char_trans_newline if keep_spacing else _control_char_trans
     return text.translate(trans)

release/cibuild.py

@@ -388,7 +388,7 @@ def build_pyinstaller(be: BuildEnviron) -> None:  # pragma: no cover
             click.echo(subprocess.check_output([executable, "--version"]).decode())
 
             archive.add(str(executable), str(executable.name))
-    click.echo("Packed {}.".format(be.archive_path.name))
+    click.echo(f"Packed {be.archive_path.name}.")
 
 
 def build_wininstaller(be: BuildEnviron) -> None:  # pragma: no cover

test/full_coverage_plugin.py

@@ -108,7 +108,7 @@ def pytest_terminal_summary(terminalreporter, exitstatus, config):
         terminalreporter.write(msg, **markup)
 
         for name in sorted(coverage_values.keys()):
-            msg = 'Coverage for {}: {:.2f}%\n'.format(name, coverage_values[name][0])
+            msg = f'Coverage for {name}: {coverage_values[name][0]:.2f}%\n'
             if coverage_values[name][0] < 100:
                 markup = {'red': True, 'bold': True}
                 for s, v in sorted(coverage_values[name][1]):

test/mitmproxy/io/test_tnetstring.py

@@ -62,7 +62,7 @@ def get_random_object(random=random, depth=0):
             else:
                 return -1 * random.randint(0, MAXINT)
         n = random.randint(0, 100)
-        return bytes([random.randint(32, 126) for _ in range(n)])
+        return bytes(random.randint(32, 126) for _ in range(n))
 
 
 class Test_Format(unittest.TestCase):

test/mitmproxy/proxy/layers/http/hyper_h2_test_helpers.py

@@ -22,7 +22,7 @@ SAMPLE_SETTINGS = {
 }
 
 
-class FrameFactory(object):
+class FrameFactory:
     """
     A class containing lots of helper methods and state to build frames. This
     allows test cases to easily build correct HTTP/2 frames to feed to

test/mitmproxy/proxy/layers/http/test_http.py

@@ -1312,9 +1312,9 @@ def test_invalid_content_length(tctx):
     flow = Placeholder(HTTPFlow)
     assert (
         Playbook(http.HttpLayer(tctx, HTTPMode.regular))
-        >> DataReceived(tctx.client, ("GET http://example.com/ HTTP/1.1\r\n"
-                                      "Host: example.com\r\n"
-                                      "Content-Length: NaN\r\n\r\n").encode())
+        >> DataReceived(tctx.client, (b"GET http://example.com/ HTTP/1.1\r\n"
+                                      b"Host: example.com\r\n"
+                                      b"Content-Length: NaN\r\n\r\n"))
         << SendData(tctx.client, err)
         << CloseConnection(tctx.client)
         << http.HttpRequestHeadersHook(flow)

test/mitmproxy/proxy/layers/test_websocket.py

@@ -27,7 +27,7 @@ class _Masked:
         other[1] &= 0b0111_1111  # remove mask bit
         assert other[1] < 126  # (we don't support extended payload length here)
         mask = other[2:6]
-        payload = bytes([x ^ mask[i % 4] for i, x in enumerate(other[6:])])
+        payload = bytes(x ^ mask[i % 4] for i, x in enumerate(other[6:]))
         return self.unmasked == other[:2] + payload
 
 
@@ -41,7 +41,7 @@ def masked_bytes(unmasked: bytes) -> bytes:
     assert header[1] < 126  # assert that this is neither masked nor extended payload
     header[1] |= 0b1000_0000
     mask = secrets.token_bytes(4)
-    masked = bytes([x ^ mask[i % 4] for i, x in enumerate(unmasked[2:])])
+    masked = bytes(x ^ mask[i % 4] for i, x in enumerate(unmasked[2:]))
     return bytes(header + mask + masked)
 
 

test/mitmproxy/test_certs.py

@@ -264,13 +264,13 @@ class TestCert:
     def test_multi_valued_rdns(self, tdata):
         subject = x509.Name([
             x509.RelativeDistinguishedName([
-                x509.NameAttribute(NameOID.TITLE, u'Test'),
-                x509.NameAttribute(NameOID.COMMON_NAME, u'Multivalue'),
-                x509.NameAttribute(NameOID.SURNAME, u'RDNs'),
-                x509.NameAttribute(NameOID.ORGANIZATION_NAME, u'TSLA'),
+                x509.NameAttribute(NameOID.TITLE, 'Test'),
+                x509.NameAttribute(NameOID.COMMON_NAME, 'Multivalue'),
+                x509.NameAttribute(NameOID.SURNAME, 'RDNs'),
+                x509.NameAttribute(NameOID.ORGANIZATION_NAME, 'TSLA'),
             ]),
             x509.RelativeDistinguishedName([
-                x509.NameAttribute(NameOID.ORGANIZATION_NAME, u'PyCA')
+                x509.NameAttribute(NameOID.ORGANIZATION_NAME, 'PyCA')
             ]),
         ])
         expected = [('2.5.4.12', 'Test'), ('CN', 'Multivalue'), ('2.5.4.4', 'RDNs'), ('O', 'TSLA'), ('O', 'PyCA')]