init

.venv/lib/python3.8/site-packages/flake8/main/application.py

@@ -0,0 +1,388 @@
+"""Module containing the application logic for Flake8."""
+import argparse
+import logging
+import sys
+import time
+from typing import Dict
+from typing import List
+from typing import Optional
+from typing import Set
+from typing import Tuple
+from typing import Type
+from typing import TYPE_CHECKING
+
+import flake8
+from flake8 import checker
+from flake8 import defaults
+from flake8 import exceptions
+from flake8 import style_guide
+from flake8 import utils
+from flake8.main import options
+from flake8.options import aggregator
+from flake8.options import config
+from flake8.options import manager
+from flake8.plugins import manager as plugin_manager
+
+if TYPE_CHECKING:
+    from flake8.formatting.base import BaseFormatter
+
+
+LOG = logging.getLogger(__name__)
+
+
+class Application:
+    """Abstract our application into a class."""
+
+    def __init__(self, program="flake8", version=flake8.__version__):
+        """Initialize our application.
+
+        :param str program:
+            The name of the program/application that we're executing.
+        :param str version:
+            The version of the program/application we're executing.
+        """
+        #: The timestamp when the Application instance was instantiated.
+        self.start_time = time.time()
+        #: The timestamp when the Application finished reported errors.
+        self.end_time: Optional[float] = None
+        #: The name of the program being run
+        self.program = program
+        #: The version of the program being run
+        self.version = version
+        #: The prelimary argument parser for handling options required for
+        #: obtaining and parsing the configuration file.
+        self.prelim_arg_parser = argparse.ArgumentParser(add_help=False)
+        options.register_preliminary_options(self.prelim_arg_parser)
+        #: The instance of :class:`flake8.options.manager.OptionManager` used
+        #: to parse and handle the options and arguments passed by the user
+        self.option_manager = manager.OptionManager(
+            prog="flake8",
+            version=flake8.__version__,
+            parents=[self.prelim_arg_parser],
+        )
+        options.register_default_options(self.option_manager)
+
+        #: The instance of :class:`flake8.plugins.manager.Checkers`
+        self.check_plugins: Optional[plugin_manager.Checkers] = None
+        #: The instance of :class:`flake8.plugins.manager.ReportFormatters`
+        self.formatting_plugins: Optional[
+            plugin_manager.ReportFormatters
+        ] = None
+        #: The user-selected formatter from :attr:`formatting_plugins`
+        self.formatter: Optional[BaseFormatter] = None
+        #: The :class:`flake8.style_guide.StyleGuideManager` built from the
+        #: user's options
+        self.guide: Optional[style_guide.StyleGuideManager] = None
+        #: The :class:`flake8.checker.Manager` that will handle running all of
+        #: the checks selected by the user.
+        self.file_checker_manager: Optional[checker.Manager] = None
+
+        #: The user-supplied options parsed into an instance of
+        #: :class:`argparse.Namespace`
+        self.options: Optional[argparse.Namespace] = None
+        #: The left over arguments that were not parsed by
+        #: :attr:`option_manager`
+        self.args: Optional[List[str]] = None
+        #: The number of errors, warnings, and other messages after running
+        #: flake8 and taking into account ignored errors and lines.
+        self.result_count = 0
+        #: The total number of errors before accounting for ignored errors and
+        #: lines.
+        self.total_result_count = 0
+        #: Whether or not something catastrophic happened and we should exit
+        #: with a non-zero status code
+        self.catastrophic_failure = False
+
+        #: Whether the program is processing a diff or not
+        self.running_against_diff = False
+        #: The parsed diff information
+        self.parsed_diff: Dict[str, Set[int]] = {}
+
+    def parse_preliminary_options(
+        self, argv: List[str]
+    ) -> Tuple[argparse.Namespace, List[str]]:
+        """Get preliminary options from the CLI, pre-plugin-loading.
+
+        We need to know the values of a few standard options so that we can
+        locate configuration files and configure logging.
+
+        Since plugins aren't loaded yet, there may be some as-yet-unknown
+        options; we ignore those for now, they'll be parsed later when we do
+        real option parsing.
+
+        :param list argv:
+            Command-line arguments passed in directly.
+        :returns:
+            Populated namespace and list of remaining argument strings.
+        :rtype:
+            (argparse.Namespace, list)
+        """
+        args, rest = self.prelim_arg_parser.parse_known_args(argv)
+        # XXX (ericvw): Special case "forwarding" the output file option so
+        # that it can be reparsed again for the BaseFormatter.filename.
+        if args.output_file:
+            rest.extend(("--output-file", args.output_file))
+        return args, rest
+
+    def exit(self) -> None:
+        """Handle finalization and exiting the program.
+
+        This should be the last thing called on the application instance. It
+        will check certain options and exit appropriately.
+        """
+        assert self.options is not None
+        if self.options.count:
+            print(self.result_count)
+
+        if self.options.exit_zero:
+            raise SystemExit(self.catastrophic_failure)
+        else:
+            raise SystemExit(
+                (self.result_count > 0) or self.catastrophic_failure
+            )
+
+    def find_plugins(self, config_finder: config.ConfigFileFinder) -> None:
+        """Find and load the plugins for this application.
+
+        Set the :attr:`check_plugins` and :attr:`formatting_plugins` attributes
+        based on the discovered plugins found.
+
+        :param config.ConfigFileFinder config_finder:
+            The finder for finding and reading configuration files.
+        """
+        local_plugins = config.get_local_plugins(config_finder)
+
+        sys.path.extend(local_plugins.paths)
+
+        self.check_plugins = plugin_manager.Checkers(local_plugins.extension)
+
+        self.formatting_plugins = plugin_manager.ReportFormatters(
+            local_plugins.report
+        )
+
+        self.check_plugins.load_plugins()
+        self.formatting_plugins.load_plugins()
+
+    def register_plugin_options(self) -> None:
+        """Register options provided by plugins to our option manager."""
+        assert self.check_plugins is not None
+        self.check_plugins.register_options(self.option_manager)
+        self.check_plugins.register_plugin_versions(self.option_manager)
+        assert self.formatting_plugins is not None
+        self.formatting_plugins.register_options(self.option_manager)
+
+    def parse_configuration_and_cli(
+        self,
+        config_finder: config.ConfigFileFinder,
+        argv: List[str],
+    ) -> None:
+        """Parse configuration files and the CLI options.
+
+        :param config.ConfigFileFinder config_finder:
+            The finder for finding and reading configuration files.
+        :param list argv:
+            Command-line arguments passed in directly.
+        """
+        self.options, self.args = aggregator.aggregate_options(
+            self.option_manager,
+            config_finder,
+            argv,
+        )
+
+        self.running_against_diff = self.options.diff
+        if self.running_against_diff:
+            self.parsed_diff = utils.parse_unified_diff()
+            if not self.parsed_diff:
+                self.exit()
+
+        assert self.check_plugins is not None
+        self.check_plugins.provide_options(
+            self.option_manager, self.options, self.args
+        )
+        assert self.formatting_plugins is not None
+        self.formatting_plugins.provide_options(
+            self.option_manager, self.options, self.args
+        )
+
+    def formatter_for(self, formatter_plugin_name):
+        """Retrieve the formatter class by plugin name."""
+        assert self.formatting_plugins is not None
+        default_formatter = self.formatting_plugins["default"]
+        formatter_plugin = self.formatting_plugins.get(formatter_plugin_name)
+        if formatter_plugin is None:
+            LOG.warning(
+                '"%s" is an unknown formatter. Falling back to default.',
+                formatter_plugin_name,
+            )
+            formatter_plugin = default_formatter
+
+        return formatter_plugin.execute
+
+    def make_formatter(
+        self, formatter_class: Optional[Type["BaseFormatter"]] = None
+    ) -> None:
+        """Initialize a formatter based on the parsed options."""
+        assert self.options is not None
+        format_plugin = self.options.format
+        if 1 <= self.options.quiet < 2:
+            format_plugin = "quiet-filename"
+        elif 2 <= self.options.quiet:
+            format_plugin = "quiet-nothing"
+
+        if formatter_class is None:
+            formatter_class = self.formatter_for(format_plugin)
+
+        self.formatter = formatter_class(self.options)
+
+    def make_guide(self) -> None:
+        """Initialize our StyleGuide."""
+        assert self.formatter is not None
+        assert self.options is not None
+        self.guide = style_guide.StyleGuideManager(
+            self.options, self.formatter
+        )
+
+        if self.running_against_diff:
+            self.guide.add_diff_ranges(self.parsed_diff)
+
+    def make_file_checker_manager(self) -> None:
+        """Initialize our FileChecker Manager."""
+        self.file_checker_manager = checker.Manager(
+            style_guide=self.guide,
+            arguments=self.args,
+            checker_plugins=self.check_plugins,
+        )
+
+    def run_checks(self, files: Optional[List[str]] = None) -> None:
+        """Run the actual checks with the FileChecker Manager.
+
+        This method encapsulates the logic to make a
+        :class:`~flake8.checker.Manger` instance run the checks it is
+        managing.
+
+        :param list files:
+            List of filenames to process
+        """
+        assert self.file_checker_manager is not None
+        if self.running_against_diff:
+            files = sorted(self.parsed_diff)
+        self.file_checker_manager.start(files)
+        try:
+            self.file_checker_manager.run()
+        except exceptions.PluginExecutionFailed as plugin_failed:
+            print(str(plugin_failed))
+            print("Run flake8 with greater verbosity to see more details")
+            self.catastrophic_failure = True
+        LOG.info("Finished running")
+        self.file_checker_manager.stop()
+        self.end_time = time.time()
+
+    def report_benchmarks(self):
+        """Aggregate, calculate, and report benchmarks for this run."""
+        assert self.options is not None
+        if not self.options.benchmark:
+            return
+
+        assert self.file_checker_manager is not None
+        assert self.end_time is not None
+        time_elapsed = self.end_time - self.start_time
+        statistics = [("seconds elapsed", time_elapsed)]
+        add_statistic = statistics.append
+        for statistic in defaults.STATISTIC_NAMES + ("files",):
+            value = self.file_checker_manager.statistics[statistic]
+            total_description = f"total {statistic} processed"
+            add_statistic((total_description, value))
+            per_second_description = f"{statistic} processed per second"
+            add_statistic((per_second_description, int(value / time_elapsed)))
+
+        assert self.formatter is not None
+        self.formatter.show_benchmarks(statistics)
+
+    def report_errors(self) -> None:
+        """Report all the errors found by flake8 3.0.
+
+        This also updates the :attr:`result_count` attribute with the total
+        number of errors, warnings, and other messages found.
+        """
+        LOG.info("Reporting errors")
+        assert self.file_checker_manager is not None
+        results = self.file_checker_manager.report()
+        self.total_result_count, self.result_count = results
+        LOG.info(
+            "Found a total of %d violations and reported %d",
+            self.total_result_count,
+            self.result_count,
+        )
+
+    def report_statistics(self):
+        """Aggregate and report statistics from this run."""
+        assert self.options is not None
+        if not self.options.statistics:
+            return
+
+        assert self.formatter is not None
+        assert self.guide is not None
+        self.formatter.show_statistics(self.guide.stats)
+
+    def initialize(self, argv: List[str]) -> None:
+        """Initialize the application to be run.
+
+        This finds the plugins, registers their options, and parses the
+        command-line arguments.
+        """
+        # NOTE(sigmavirus24): When updating this, make sure you also update
+        # our legacy API calls to these same methods.
+        prelim_opts, remaining_args = self.parse_preliminary_options(argv)
+        flake8.configure_logging(prelim_opts.verbose, prelim_opts.output_file)
+        config_finder = config.ConfigFileFinder(
+            self.program,
+            prelim_opts.append_config,
+            config_file=prelim_opts.config,
+            ignore_config_files=prelim_opts.isolated,
+        )
+        self.find_plugins(config_finder)
+        self.register_plugin_options()
+        self.parse_configuration_and_cli(
+            config_finder,
+            remaining_args,
+        )
+        self.make_formatter()
+        self.make_guide()
+        self.make_file_checker_manager()
+
+    def report(self):
+        """Report errors, statistics, and benchmarks."""
+        assert self.formatter is not None
+        self.formatter.start()
+        self.report_errors()
+        self.report_statistics()
+        self.report_benchmarks()
+        self.formatter.stop()
+
+    def _run(self, argv: List[str]) -> None:
+        self.initialize(argv)
+        self.run_checks()
+        self.report()
+
+    def run(self, argv: List[str]) -> None:
+        """Run our application.
+
+        This method will also handle KeyboardInterrupt exceptions for the
+        entirety of the flake8 application. If it sees a KeyboardInterrupt it
+        will forcibly clean up the :class:`~flake8.checker.Manager`.
+        """
+        try:
+            self._run(argv)
+        except KeyboardInterrupt as exc:
+            print("... stopped")
+            LOG.critical("Caught keyboard interrupt from user")
+            LOG.exception(exc)
+            self.catastrophic_failure = True
+        except exceptions.ExecutionError as exc:
+            print("There was a critical error during execution of Flake8:")
+            print(exc)
+            LOG.exception(exc)
+            self.catastrophic_failure = True
+        except exceptions.EarlyQuit:
+            self.catastrophic_failure = True
+            print("... stopped while processing files")