"""Module containing shims around Flake8 2.x behaviour.
Previously, users would import :func:`get_style_guide` from ``flake8.engine``.
In 3.0 we no longer have an "engine" module but we maintain the API from it.
"""
import argparse
import logging
import os.path
from typing import Any
from typing import List
from typing import Optional
from typing import Type
import flake8
from flake8.discover_files import expand_paths
from flake8.formatting import base as formatter
from flake8.main import application as app
from flake8.options import config
LOG = logging.getLogger(__name__)
__all__ = ("get_style_guide",)
[docs]class Report:
"""Public facing object that mimic's Flake8 2.0's API.
.. note::
There are important changes in how this object behaves compared to
the object provided in Flake8 2.x.
.. warning::
This should not be instantiated by users.
.. versionchanged:: 3.0.0
"""
def __init__(self, application: app.Application) -> None:
"""Initialize the Report for the user.
.. warning:: This should not be instantiated by users.
"""
assert application.guide is not None
self._application = application
self._style_guide = application.guide
self._stats = self._style_guide.stats
@property
def total_errors(self) -> int:
"""Return the total number of errors."""
return self._application.result_count
[docs] def get_statistics(self, violation: str) -> List[str]:
"""Get the list of occurrences of a violation.
:returns:
List of occurrences of a violation formatted as:
{Count} {Error Code} {Message}, e.g.,
``8 E531 Some error message about the error``
"""
return [
f"{s.count} {s.error_code} {s.message}"
for s in self._stats.statistics_for(violation)
]
[docs]class StyleGuide:
"""Public facing object that mimic's Flake8 2.0's StyleGuide.
.. note::
There are important changes in how this object behaves compared to
the StyleGuide object provided in Flake8 2.x.
.. warning::
This object should not be instantiated directly by users.
.. versionchanged:: 3.0.0
"""
def __init__(self, application: app.Application) -> None:
"""Initialize our StyleGuide."""
self._application = application
self._file_checker_manager = application.file_checker_manager
@property
def options(self) -> argparse.Namespace:
"""Return application's options.
An instance of :class:`argparse.Namespace` containing parsed options.
"""
assert self._application.options is not None
return self._application.options
@property
def paths(self) -> List[str]:
"""Return the extra arguments passed as paths."""
assert self._application.options is not None
return self._application.options.filenames
[docs] def check_files(self, paths: Optional[List[str]] = None) -> Report:
"""Run collected checks on the files provided.
This will check the files passed in and return a :class:`Report`
instance.
:param paths:
List of filenames (or paths) to check.
:returns:
Object that mimic's Flake8 2.0's Reporter class.
"""
assert self._application.options is not None
self._application.options.filenames = paths
self._application.run_checks()
self._application.report_errors()
return Report(self._application)
[docs] def excluded(self, filename: str, parent: Optional[str] = None) -> bool:
"""Determine if a file is excluded.
:param filename:
Path to the file to check if it is excluded.
:param parent:
Name of the parent directory containing the file.
:returns:
True if the filename is excluded, False otherwise.
"""
def excluded(path: str) -> bool:
paths = tuple(
expand_paths(
paths=[path],
stdin_display_name=self.options.stdin_display_name,
filename_patterns=self.options.filename,
exclude=self.options.exclude,
is_running_from_diff=self.options.diff,
)
)
return not paths
return excluded(filename) or (
parent is not None and excluded(os.path.join(parent, filename))
)
[docs] def init_report(
self,
reporter: Optional[Type[formatter.BaseFormatter]] = None,
) -> None:
"""Set up a formatter for this run of Flake8."""
if reporter is None:
return
if not issubclass(reporter, formatter.BaseFormatter):
raise ValueError(
"Report should be subclass of "
"flake8.formatter.BaseFormatter."
)
self._application.formatter = reporter(self.options)
self._application.guide = None
# NOTE(sigmavirus24): This isn't the intended use of
# Application#make_guide but it works pretty well.
# Stop cringing... I know it's gross.
self._application.make_guide()
self._application.file_checker_manager = None
self._application.make_file_checker_manager()
[docs]def get_style_guide(**kwargs: Any) -> StyleGuide:
r"""Provision a StyleGuide for use.
:param \*\*kwargs:
Keyword arguments that provide some options for the StyleGuide.
:returns:
An initialized StyleGuide
"""
application = app.Application()
prelim_opts, remaining_args = application.parse_preliminary_options([])
flake8.configure_logging(prelim_opts.verbose, prelim_opts.output_file)
cfg, cfg_dir = config.load_config(
config=prelim_opts.config,
extra=prelim_opts.append_config,
isolated=prelim_opts.isolated,
)
application.find_plugins(
cfg,
cfg_dir,
enable_extensions=prelim_opts.enable_extensions,
require_plugins=prelim_opts.require_plugins,
)
application.register_plugin_options()
application.parse_configuration_and_cli(cfg, cfg_dir, remaining_args)
# We basically want application.initialize to be called but with these
# options set instead before we make our formatter, notifier, internal
# style guide and file checker manager.
options = application.options
for key, value in kwargs.items():
try:
getattr(options, key)
setattr(options, key, value)
except AttributeError:
LOG.error('Could not update option "%s"', key)
application.make_formatter()
application.make_guide()
application.make_file_checker_manager()
return StyleGuide(application)