audit + string joining

src/flake8/main/application.py

@@ -275,9 +275,9 @@ class Application:
         add_statistic = statistics.append
         for statistic in defaults.STATISTIC_NAMES + ("files",):
             value = self.file_checker_manager.statistics[statistic]
-            total_description = "total " + statistic + " processed"
+            total_description = f"total {statistic} processed"
             add_statistic((total_description, value))
-            per_second_description = statistic + " processed per second"
+            per_second_description = f"{statistic} processed per second"
             add_statistic((per_second_description, int(value / time_elapsed)))
 
         self.formatter.show_benchmarks(statistics)

src/flake8/options/config.py

@@ -51,7 +51,7 @@ class ConfigFileFinder:
         self.user_config_file = self._user_config_file(program_name)
 
         # List of filenames to find in the local/project directory
-        self.project_filenames = ("setup.cfg", "tox.ini", "." + program_name)
+        self.project_filenames = ("setup.cfg", "tox.ini", f".{program_name}")
 
         self.local_directory = os.path.abspath(os.curdir)
 
@@ -59,7 +59,7 @@ class ConfigFileFinder:
     def _user_config_file(program_name: str) -> str:
         if utils.is_windows():
             home_dir = os.path.expanduser("~")
-            config_file_basename = "." + program_name
+            config_file_basename = f".{program_name}"
         else:
             home_dir = os.environ.get(
                 "XDG_CONFIG_HOME", os.path.expanduser("~/.config")

src/flake8/plugins/pyflakes.py

@@ -145,7 +145,7 @@ class FlakesChecker(pyflakes.checker.Checker):
             if included_file == "":
                 continue
             if not included_file.startswith((os.sep, "./", "~/")):
-                included_files.append("./" + included_file)
+                included_files.append(f"./{included_file}")
             else:
                 included_files.append(included_file)
         cls.include_in_doctest = utils.normalize_paths(included_files)
@@ -155,7 +155,7 @@ class FlakesChecker(pyflakes.checker.Checker):
             if excluded_file == "":
                 continue
             if not excluded_file.startswith((os.sep, "./", "~/")):
-                excluded_files.append("./" + excluded_file)
+                excluded_files.append(f"./{excluded_file}")
             else:
                 excluded_files.append(excluded_file)
         cls.exclude_from_doctest = utils.normalize_paths(excluded_files)

src/flake8/processor.py

@@ -218,7 +218,7 @@ class FileProcessor:
                     if previous_text == "," or (
                         previous_text not in "{[(" and text not in "}])"
                     ):
-                        text = " " + text
+                        text = f" {text}"
                 elif previous_column != start_column:
                     text = line[previous_column:start_column] + text
             logical.append(text)

src/flake8/utils.py

@@ -9,6 +9,7 @@ import os
 import platform
 import re
 import sys
+import textwrap
 import tokenize
 from typing import Callable
 from typing import Dict
@@ -122,13 +123,11 @@ def parse_files_to_codes_mapping(  # noqa: C901
         State.codes = []
 
     def _unexpected_token() -> exceptions.ExecutionError:
-        def _indent(s: str) -> str:
-            return "    " + s.strip().replace("\n", "\n    ")
-
         return exceptions.ExecutionError(
             f"Expected `per-file-ignores` to be a mapping from file exclude "
             f"patterns to ignore codes.\n\n"
-            f"Configured `per-file-ignores` setting:\n\n{_indent(value)}"
+            f"Configured `per-file-ignores` setting:\n\n"
+            f"{textwrap.indent(value.strip(), '    ')}"
         )
 
     for token in _tokenize_files_to_codes_mapping(value):

tests/unit/test_utils.py

@@ -134,7 +134,7 @@ def test_normalize_path(value, expected):
     (["flake8", "pep8", "pyflakes", "mccabe"],
         ["flake8", "pep8", "pyflakes", "mccabe"]),
     (["../flake8", "../pep8", "../pyflakes", "../mccabe"],
-        [os.path.abspath("../" + p) for p in RELATIVE_PATHS]),
+        [os.path.abspath(f"../{p}") for p in RELATIVE_PATHS]),
 ])
 def test_normalize_paths(value, expected):
     """Verify we normalizes a sequence of paths provided to the tool."""