Add pylint to depot_tools.

third_party/pylint/lint.py

+# Copyright (c) 2003-2010 Sylvain Thenault (thenault@gmail.com).
+# Copyright (c) 2003-2010 LOGILAB S.A. (Paris, FRANCE).
+# http://www.logilab.fr/ -- mailto:contact@logilab.fr
+#
+# This program is free software; you can redistribute it and/or modify it under
+# the terms of the GNU General Public License as published by the Free Software
+# Foundation; either version 2 of the License, or (at your option) any later
+# version.
+#
+# This program is distributed in the hope that it will be useful, but WITHOUT
+# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+# FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details
+#
+# You should have received a copy of the GNU General Public License along with
+# this program; if not, write to the Free Software Foundation, Inc.,
+# 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
+""" %prog [options] module_or_package
+
+  Check that a module satisfy a coding standard (and more !).
+
+    %prog --help
+
+  Display this help message and exit.
+
+    %prog --help-msg <msg-id>[,<msg-id>]
+
+  Display help messages about given message identifiers and exit.
+"""
+
+# import this first to avoid builtin namespace pollution
+from pylint.checkers import utils
+
+import sys
+import os
+import re
+import tokenize
+from warnings import warn
+
+from logilab.common.configuration import UnsupportedAction, OptionsManagerMixIn
+from logilab.common.optik_ext import check_csv
+from logilab.common.modutils import load_module_from_name
+from logilab.common.interface import implements
+from logilab.common.textutils import splitstrip
+from logilab.common.ureports import Table, Text, Section
+from logilab.common.__pkginfo__ import version as common_version
+
+from logilab.astng import MANAGER, nodes, ASTNGBuildingException
+from logilab.astng.__pkginfo__ import version as astng_version
+
+from pylint.utils import PyLintASTWalker, UnknownMessage, MessagesHandlerMixIn,\
+     ReportsHandlerMixIn, MSG_TYPES, expand_modules
+from pylint.interfaces import ILinter, IRawChecker, IASTNGChecker
+from pylint.checkers import BaseRawChecker, EmptyReport, \
+     table_lines_from_stats
+from pylint.reporters.text import TextReporter, ParseableTextReporter, \
+     VSTextReporter, ColorizedTextReporter
+from pylint.reporters.html import HTMLReporter
+from pylint import config
+
+from pylint.__pkginfo__ import version
+
+
+OPTION_RGX = re.compile('\s*#*\s*pylint:(.*)')
+REPORTER_OPT_MAP = {'text': TextReporter,
+                    'parseable': ParseableTextReporter,
+                    'msvs': VSTextReporter,
+                    'colorized': ColorizedTextReporter,
+                    'html': HTMLReporter,}
+
+
+# Python Linter class #########################################################
+
+MSGS = {
+    'F0001': ('%s',
+              'Used when an error occurred preventing the analysis of a \
+              module (unable to find it for instance).'),
+    'F0002': ('%s: %s',
+              'Used when an unexpected error occurred while building the ASTNG \
+              representation. This is usually accompanied by a traceback. \
+              Please report such errors !'),
+    'F0003': ('ignored builtin module %s',
+              'Used to indicate that the user asked to analyze a builtin module\
+              which has been skipped.'),
+    'F0004': ('unexpected inferred value %s',
+              'Used to indicate that some value of an unexpected type has been \
+              inferred.'),
+    'F0010': ('error while code parsing: %s',
+              'Used when an exception occured while building the ASTNG \
+               representation which could be handled by astng.'),
+
+
+    'I0001': ('Unable to run raw checkers on built-in module %s',
+              'Used to inform that a built-in module has not been checked \
+              using the raw checkers.'),
+
+    'I0010': ('Unable to consider inline option %r',
+              'Used when an inline option is either badly formatted or can\'t \
+              be used inside modules.'),
+
+    'I0011': ('Locally disabling %s',
+              'Used when an inline option disables a message or a messages \
+              category.'),
+    'I0012': ('Locally enabling %s',
+              'Used when an inline option enables a message or a messages \
+              category.'),
+    'I0013': ('Ignoring entire file',
+              'Used to inform that the file will not be checked'),
+
+
+    'E0001': ('%s',
+              'Used when a syntax error is raised for a module.'),
+
+    'E0011': ('Unrecognized file option %r',
+              'Used when an unknown inline option is encountered.'),
+    'E0012': ('Bad option value %r',
+              'Used when a bad value for an inline option is encountered.'),
+    }
+
+
+class PyLinter(OptionsManagerMixIn, MessagesHandlerMixIn, ReportsHandlerMixIn,
+               BaseRawChecker):
+    """lint Python modules using external checkers.
+
+    This is the main checker controlling the other ones and the reports
+    generation. It is itself both a raw checker and an astng checker in order
+    to:
+    * handle message activation / deactivation at the module level
+    * handle some basic but necessary stats'data (number of classes, methods...)
+
+    IDE plugins developpers: you may have to call
+    `logilab.astng.builder.MANAGER.astng_cache.clear()` accross run if you want
+    to ensure the latest code version is actually checked.
+    """
+
+    __implements__ = (ILinter, IRawChecker)
+
+    name = 'master'
+    priority = 0
+    level = 0
+    msgs = MSGS
+    may_be_disabled = False
+
+    @staticmethod
+    def make_options():
+        return (('ignore',
+                 {'type' : 'csv', 'metavar' : '<file>[,<file>...]',
+                  'dest' : 'black_list', 'default' : ('CVS',),
+                  'help' : 'Add files or directories to the blacklist. \
+They should be base names, not paths.'}),
+                ('persistent',
+                 {'default': True, 'type' : 'yn', 'metavar' : '<y_or_n>',
+                  'level': 1,
+                  'help' : 'Pickle collected data for later comparisons.'}),
+
+                ('load-plugins',
+                 {'type' : 'csv', 'metavar' : '<modules>', 'default' : (),
+                  'level': 1,
+                  'help' : 'List of plugins (as comma separated values of \
+python modules names) to load, usually to register additional checkers.'}),
+
+                ('output-format',
+                 {'default': 'text', 'type': 'choice', 'metavar' : '<format>',
+                  'choices': REPORTER_OPT_MAP.keys(),
+                  'short': 'f',
+                  'group': 'Reports',
+                  'help' : 'Set the output format. Available formats are text,\
+                 parseable, colorized, msvs (visual studio) and html'}),
+
+                ('include-ids',
+                 {'type' : 'yn', 'metavar' : '<y_or_n>', 'default' : 0,
+                  'short': 'i',
+                  'group': 'Reports',
+                  'help' : 'Include message\'s id in output'}),
+
+                ('files-output',
+                 {'default': 0, 'type' : 'yn', 'metavar' : '<y_or_n>',
+                  'group': 'Reports', 'level': 1,
+                  'help' : 'Put messages in a separate file for each module / \
+package specified on the command line instead of printing them on stdout. \
+Reports (if any) will be written in a file name "pylint_global.[txt|html]".'}),
+
+                ('reports',
+                 {'default': 1, 'type' : 'yn', 'metavar' : '<y_or_n>',
+                  'short': 'r',
+                  'group': 'Reports',
+                  'help' : 'Tells whether to display a full report or only the\
+ messages'}),
+
+                ('evaluation',
+                 {'type' : 'string', 'metavar' : '<python_expression>',
+                  'group': 'Reports', 'level': 1,
+                  'default': '10.0 - ((float(5 * error + warning + refactor + \
+convention) / statement) * 10)',
+                  'help' : 'Python expression which should return a note less \
+than 10 (10 is the highest note). You have access to the variables errors \
+warning, statement which respectively contain the number of errors / warnings\
+ messages and the total number of statements analyzed. This is used by the \
+ global evaluation report (RP0004).'}),
+
+                ('comment',
+                 {'default': 0, 'type' : 'yn', 'metavar' : '<y_or_n>',
+                  'group': 'Reports', 'level': 1,
+                  'help' : 'Add a comment according to your evaluation note. \
+This is used by the global evaluation report (RP0004).'}),
+
+                ('enable',
+                 {'type' : 'csv', 'metavar': '<msg ids>',
+                  'short': 'e',
+                  'group': 'Messages control',
+                  'help' : 'Enable the message, report, category or checker with the '
+                  'given id(s). You can either give multiple identifier '
+                  'separated by comma (,) or put this option multiple time.'}),
+
+                ('disable',
+                 {'type' : 'csv', 'metavar': '<msg ids>',
+                  'short': 'd',
+                  'group': 'Messages control',
+                  'help' : 'Disable the message, report, category or checker '
+                  'with the given id(s). You can either give multiple identifier'
+                  ' separated by comma (,) or put this option multiple time '
+                  '(only on the command line, not in the configuration file '
+                  'where it should appear only once).'}),
+               )
+
+    option_groups = (
+        ('Messages control', 'Options controling analysis messages'),
+        ('Reports', 'Options related to output formating and reporting'),
+        )
+
+    def __init__(self, options=(), reporter=None, option_groups=(),
+                 pylintrc=None):
+        # some stuff has to be done before ancestors initialization...
+        #
+        # checkers / reporter / astng manager
+        self.reporter = None
+        self._checkers = {}
+        self._ignore_file = False
+        # visit variables
+        self.base_name = None
+        self.base_file = None
+        self.current_name = None
+        self.current_file = None
+        self.stats = None
+        # init options
+        self.options = options + PyLinter.make_options()
+        self.option_groups = option_groups + PyLinter.option_groups
+        self._options_methods = {
+            'enable': self.enable,
+            'disable': self.disable}
+        self._bw_options_methods = {'disable-msg': self.disable,
+                                    'enable-msg': self.enable}
+        full_version = '%%prog %s, \nastng %s, common %s\nPython %s' % (
+            version, astng_version, common_version, sys.version)
+        OptionsManagerMixIn.__init__(self, usage=__doc__,
+                                     version=full_version,
+                                     config_file=pylintrc or config.PYLINTRC)
+        MessagesHandlerMixIn.__init__(self)
+        ReportsHandlerMixIn.__init__(self)
+        BaseRawChecker.__init__(self)
+        # provided reports
+        self.reports = (('RP0001', 'Messages by category',
+                         report_total_messages_stats),
+                        ('RP0002', '% errors / warnings by module',
+                         report_messages_by_module_stats),
+                        ('RP0003', 'Messages',
+                         report_messages_stats),
+                        ('RP0004', 'Global evaluation',
+                         self.report_evaluation),
+                        )
+        self.register_checker(self)
+        self._dynamic_plugins = []
+        self.load_provider_defaults()
+        self.set_reporter(reporter or TextReporter(sys.stdout))
+
+    def load_default_plugins(self):
+        from pylint import checkers
+        checkers.initialize(self)
+
+    def load_plugin_modules(self, modnames):
+        """take a list of module names which are pylint plugins and load
+        and register them
+        """
+        for modname in modnames:
+            if modname in self._dynamic_plugins:
+                continue
+            self._dynamic_plugins.append(modname)
+            module = load_module_from_name(modname)
+            module.register(self)
+
+    def set_reporter(self, reporter):
+        """set the reporter used to display messages and reports"""
+        self.reporter = reporter
+        reporter.linter = self
+
+    def set_option(self, optname, value, action=None, optdict=None):
+        """overridden from configuration.OptionsProviderMixin to handle some
+        special options
+        """
+        if optname in self._options_methods or optname in self._bw_options_methods:
+            if value:
+                try:
+                    meth = self._options_methods[optname]
+                except KeyError:
+                    meth = self._bw_options_methods[optname]
+                    warn('%s is deprecated, replace it by %s' % (
+                        optname, optname.split('-')[0]), DeprecationWarning)
+                value = check_csv(None, optname, value)
+                if isinstance(value, (list, tuple)):
+                    for _id in value :
+                        meth(_id)
+                else :
+                    meth(value)
+        elif optname == 'output-format':
+            self.set_reporter(REPORTER_OPT_MAP[value.lower()]())
+        try:
+            BaseRawChecker.set_option(self, optname, value, action, optdict)
+        except UnsupportedAction:
+            print >> sys.stderr, 'option %s can\'t be read from config file' % \
+                  optname
+
+    # checkers manipulation methods ############################################
+
+    def register_checker(self, checker):
+        """register a new checker
+
+        checker is an object implementing IRawChecker or / and IASTNGChecker
+        """
+        assert checker.priority <= 0, 'checker priority can\'t be >= 0'
+        self._checkers.setdefault(checker.name, []).append(checker)
+        for r_id, r_title, r_cb in checker.reports:
+            self.register_report(r_id, r_title, r_cb, checker)
+        self.register_options_provider(checker)
+        if hasattr(checker, 'msgs'):
+            self.register_messages(checker)
+        checker.load_defaults()
+
+    def disable_noerror_messages(self):
+        for msgcat, msgids in self._msgs_by_category.iteritems():
+            if msgcat == 'E':
+                for msgid in msgids:
+                    self.enable(msgid)
+            else:
+                for msgid in msgids:
+                    self.disable(msgid)
+
+    def disable_reporters(self):
+       """disable all reporters"""
+       for reporters in self._reports.values():
+           for report_id, _title, _cb in reporters:
+               self.disable_report(report_id)
+
+    def error_mode(self):
+        """error mode: enable only errors; no reports, no persistent"""
+        self.disable_noerror_messages()
+        self.disable('miscellaneous')
+        self.set_option('reports', False)
+        self.set_option('persistent', False)
+
+    # block level option handling #############################################
+    #
+    # see func_block_disable_msg.py test case for expected behaviour
+
+    def process_tokens(self, tokens):
+        """process tokens from the current module to search for module/block
+        level options
+        """
+        comment = tokenize.COMMENT
+        newline = tokenize.NEWLINE
+        for (tok_type, _, start, _, line) in tokens:
+            if tok_type not in (comment, newline):
+                continue
+            match = OPTION_RGX.search(line)
+            if match is None:
+                continue
+            if match.group(1).strip() == "disable-all":
+                self.add_message('I0013', line=start[0])
+                self._ignore_file = True
+                return
+            try:
+                opt, value = match.group(1).split('=', 1)
+            except ValueError:
+                self.add_message('I0010', args=match.group(1).strip(),
+                                 line=start[0])
+                continue
+            opt = opt.strip()
+            if opt in self._options_methods or opt in self._bw_options_methods:
+                try:
+                    meth = self._options_methods[opt]
+                except KeyError:
+                    meth = self._bw_options_methods[opt]
+                    warn('%s is deprecated, replace it by %s (%s, line %s)' % (
+                        opt, opt.split('-')[0], self.current_file, line),
+                         DeprecationWarning)
+                for msgid in splitstrip(value):
+                    try:
+                        meth(msgid, 'module', start[0])
+                    except UnknownMessage:
+                        self.add_message('E0012', args=msgid, line=start[0])
+            else:
+                self.add_message('E0011', args=opt, line=start[0])
+
+    def collect_block_lines(self, node, msg_state):
+        """walk ast to collect block level options line numbers"""
+        # recurse on children (depth first)
+        for child in node.get_children():
+            self.collect_block_lines(child, msg_state)
+        first = node.fromlineno
+        last = node.tolineno
+        # first child line number used to distinguish between disable
+        # which are the first child of scoped node with those defined later.
+        # For instance in the code below:
+        #
+        # 1.   def meth8(self):
+        # 2.        """test late disabling"""
+        # 3.        # pylint: disable=E1102
+        # 4.        print self.blip
+        # 5.        # pylint: disable=E1101
+        # 6.        print self.bla
+        #
+        # E1102 should be disabled from line 1 to 6 while E1101 from line 5 to 6
+        #
+        # this is necessary to disable locally messages applying to class /
+        # function using their fromlineno
+        if isinstance(node, (nodes.Module, nodes.Class, nodes.Function)) and node.body:
+            firstchildlineno = node.body[0].fromlineno
+        else:
+            firstchildlineno = last
+        for msgid, lines in msg_state.iteritems():
+            for lineno, state in lines.items():
+                if first <= lineno <= last:
+                    if lineno > firstchildlineno:
+                        state = True
+                    # set state for all lines for this block
+                    first, last = node.block_range(lineno)
+                    for line in xrange(first, last+1):
+                        # do not override existing entries
+                        if not line in self._module_msgs_state.get(msgid, ()):
+                            if line in lines: # state change in the same block
+                                state = lines[line]
+                            try:
+                                self._module_msgs_state[msgid][line] = state
+                            except KeyError:
+                                self._module_msgs_state[msgid] = {line: state}
+                    del lines[lineno]
+
+
+    # code checking methods ###################################################
+
+    def get_checkers(self):
+        """return all available checkers as a list"""
+        return [self] + [c for checkers in self._checkers.values()
+                         for c in checkers if c is not self]
+
+    def prepare_checkers(self):
+        """return checkers needed for activated messages and reports"""
+        if not self.config.reports:
+            self.disable_reporters()
+        # get needed checkers
+        neededcheckers = [self]
+        for checker in self.get_checkers()[1:]:
+            messages = set(msg for msg in checker.msgs
+                           if self.is_message_enabled(msg))
+            if (messages or
+                any(self.report_is_enabled(r[0]) for r in checker.reports)):
+                neededcheckers.append(checker)
+                checker.active_msgs = messages
+        return neededcheckers
+
+    def check(self, files_or_modules):
+        """main checking entry: check a list of files or modules from their
+        name.
+        """
+        self.reporter.include_ids = self.config.include_ids
+        if not isinstance(files_or_modules, (list, tuple)):
+            files_or_modules = (files_or_modules,)
+        walker = PyLintASTWalker(self)
+        checkers = self.prepare_checkers()
+        rawcheckers = [c for c in checkers if implements(c, IRawChecker)
+                       and c is not self]
+        # notify global begin
+        for checker in checkers:
+            checker.open()
+            if implements(checker, IASTNGChecker):
+                walker.add_checker(checker)
+        # build ast and check modules or packages
+        for descr in self.expand_files(files_or_modules):
+            modname, filepath = descr['name'], descr['path']
+            self.set_current_module(modname, filepath)
+            # get the module representation
+            astng = self.get_astng(filepath, modname)
+            if astng is None:
+                continue
+            self.base_name = descr['basename']
+            self.base_file = descr['basepath']
+            if self.config.files_output:
+                reportfile = 'pylint_%s.%s' % (modname, self.reporter.extension)
+                self.reporter.set_output(open(reportfile, 'w'))
+            self._ignore_file = False
+            # fix the current file (if the source file was not available or
+            # if it's actually a c extension)
+            self.current_file = astng.file
+            self.check_astng_module(astng, walker, rawcheckers)
+        # notify global end
+        self.set_current_module('')
+        self.stats['statement'] = walker.nbstatements
+        checkers.reverse()
+        for checker in checkers:
+            checker.close()
+
+    def expand_files(self, modules):
+        """get modules and errors from a list of modules and handle errors
+        """
+        result, errors = expand_modules(modules, self.config.black_list)
+        for error in errors:
+            message = modname = error["mod"]
+            key = error["key"]
+            self.set_current_module(modname)
+            if key == "F0001":
+                message = str(error["ex"]).replace(os.getcwd() + os.sep, '')
+            self.add_message(key, args=message)
+        return result
+
+    def set_current_module(self, modname, filepath=None):
+        """set the name of the currently analyzed module and
+        init statistics for it
+        """
+        if not modname and filepath is None:
+            return
+        self.current_name = modname
+        self.current_file = filepath or modname
+        self.stats['by_module'][modname] = {}
+        self.stats['by_module'][modname]['statement'] = 0
+        for msg_cat in MSG_TYPES.values():
+            self.stats['by_module'][modname][msg_cat] = 0
+        # XXX hack, to be correct we need to keep module_msgs_state
+        # for every analyzed module (the problem stands with localized
+        # messages which are only detected in the .close step)
+        if modname:
+            self._module_msgs_state = {}
+            self._module_msg_cats_state = {}
+
+    def get_astng(self, filepath, modname):
+        """return a astng representation for a module"""
+        try:
+            return MANAGER.astng_from_file(filepath, modname, source=True)
+        except SyntaxError, ex:
+            self.add_message('E0001', line=ex.lineno, args=ex.msg)
+        except ASTNGBuildingException, ex:
+            self.add_message('F0010', args=ex)
+        except Exception, ex:
+            import traceback
+            traceback.print_exc()
+            self.add_message('F0002', args=(ex.__class__, ex))
+
+    def check_astng_module(self, astng, walker, rawcheckers):
+        """check a module from its astng representation, real work"""
+        # call raw checkers if possible
+        if not astng.pure_python:
+            self.add_message('I0001', args=astng.name)
+        else:
+            #assert astng.file.endswith('.py')
+            # invoke IRawChecker interface on self to fetch module/block
+            # level options
+            self.process_module(astng)
+            if self._ignore_file:
+                return False
+            # walk ast to collect line numbers
+            orig_state = self._module_msgs_state.copy()
+            self._module_msgs_state = {}
+            self.collect_block_lines(astng, orig_state)
+            for checker in rawcheckers:
+                checker.process_module(astng)
+        # generate events to astng checkers
+        walker.walk(astng)
+        return True
+
+    # IASTNGChecker interface #################################################
+
+    def open(self):
+        """initialize counters"""
+        self.stats = { 'by_module' : {},
+                       'by_msg' : {},
+                       }
+        for msg_cat in MSG_TYPES.values():
+            self.stats[msg_cat] = 0
+
+    def close(self):
+        """close the whole package /module, it's time to make reports !
+
+        if persistent run, pickle results for later comparison
+        """
+        if self.base_name is not None:
+            # load old results if any
+            old_stats = config.load_results(self.base_name)
+            if self.config.reports:
+                self.make_reports(self.stats, old_stats)
+            elif self.config.output_format == 'html':
+                self.reporter.display_results(Section())
+            # save results if persistent run
+            if self.config.persistent:
+                config.save_results(self.stats, self.base_name)
+
+    # specific reports ########################################################
+
+    def report_evaluation(self, sect, stats, old_stats):
+        """make the global evaluation report"""
+        # check with at least check 1 statements (usually 0 when there is a
+        # syntax error preventing pylint from further processing)
+        if stats['statement'] == 0:
+            raise EmptyReport()
+        # get a global note for the code
+        evaluation = self.config.evaluation
+        try:
+            note = eval(evaluation, {}, self.stats)
+        except Exception, ex:
+            msg = 'An exception occurred while rating: %s' % ex
+        else:
+            stats['global_note'] = note
+            msg = 'Your code has been rated at %.2f/10' % note
+            if 'global_note' in old_stats:
+                msg += ' (previous run: %.2f/10)' % old_stats['global_note']
+            if self.config.comment:
+                msg = '%s\n%s' % (msg, config.get_note_message(note))
+        sect.append(Text(msg))
+
+# some reporting functions ####################################################
+
+def report_total_messages_stats(sect, stats, old_stats):
+    """make total errors / warnings report"""
+    lines = ['type', 'number', 'previous', 'difference']
+    lines += table_lines_from_stats(stats, old_stats,
+                                    ('convention', 'refactor',
+                                     'warning', 'error'))
+    sect.append(Table(children=lines, cols=4, rheaders=1))
+
+def report_messages_stats(sect, stats, _):
+    """make messages type report"""
+    if not stats['by_msg']:
+        # don't print this report when we didn't detected any errors
+        raise EmptyReport()
+    in_order = sorted([(value, msg_id) 
+                       for msg_id, value in stats['by_msg'].items()
+                       if not msg_id.startswith('I')])
+    in_order.reverse()
+    lines = ('message id', 'occurrences')
+    for value, msg_id in in_order:
+        lines += (msg_id, str(value))
+    sect.append(Table(children=lines, cols=2, rheaders=1))
+
+def report_messages_by_module_stats(sect, stats, _):
+    """make errors / warnings by modules report"""
+    if len(stats['by_module']) == 1:
+        # don't print this report when we are analysing a single module
+        raise EmptyReport()
+    by_mod = {}
+    for m_type in ('fatal', 'error', 'warning', 'refactor', 'convention'):
+        total = stats[m_type]
+        for module in stats['by_module'].keys():
+            mod_total = stats['by_module'][module][m_type]
+            if total == 0:
+                percent = 0
+            else:
+                percent = float((mod_total)*100) / total
+            by_mod.setdefault(module, {})[m_type] = percent
+    sorted_result = []
+    for module, mod_info in by_mod.items():
+        sorted_result.append((mod_info['error'],
+                              mod_info['warning'],
+                              mod_info['refactor'],
+                              mod_info['convention'],
+                              module))
+    sorted_result.sort()
+    sorted_result.reverse()
+    lines = ['module', 'error', 'warning', 'refactor', 'convention']
+    for line in sorted_result:
+        if line[0] == 0 and line[1] == 0:
+            break
+        lines.append(line[-1])
+        for val in line[:-1]:
+            lines.append('%.2f' % val)
+    if len(lines) == 5:
+        raise EmptyReport()
+    sect.append(Table(children=lines, cols=5, rheaders=1))
+
+
+# utilities ###################################################################
+
+# this may help to import modules using gettext
+
+try:
+    __builtins__._ = str
+except AttributeError:
+    __builtins__['_'] = str
+
+
+class ArgumentPreprocessingError(Exception):
+    """Raised if an error occurs during argument preprocessing."""
+
+
+def preprocess_options(args, search_for):
+    """look for some options (keys of <search_for>) which have to be processed
+    before others
+
+    values of <search_for> are callback functions to call when the option is
+    found
+    """
+    i = 0
+    while i < len(args):
+        arg = args[i]
+        if arg.startswith('--'):
+            try:
+                option, val = arg[2:].split('=', 1)
+            except ValueError:
+                option, val = arg[2:], None
+            try:
+                cb, takearg = search_for[option]
+                del args[i]
+                if takearg and val is None:
+                    if i >= len(args) or args[i].startswith('-'):
+                        raise ArgumentPreprocessingError(arg)
+                    val = args[i]
+                    del args[i]
+                cb(option, val)
+            except KeyError:
+                i += 1
+        else:
+            i += 1
+
+class Run:
+    """helper class to use as main for pylint :
+
+    run(*sys.argv[1:])
+    """
+    LinterClass = PyLinter
+    option_groups = (
+        ('Commands', 'Options which are actually commands. Options in this \
+group are mutually exclusive.'),
+        )
+
+    def __init__(self, args, reporter=None, exit=True):
+        self._rcfile = None
+        self._plugins = []
+        try:
+            preprocess_options(args, {
+                # option: (callback, takearg)
+                'rcfile':       (self.cb_set_rcfile, True),
+                'load-plugins': (self.cb_add_plugins, True),
+                })
+        except ArgumentPreprocessingError, e:
+            print >> sys.stderr, 'Argument %s expects a value.' % (e.args[0],)
+            sys.exit(32)
+
+        self.linter = linter = self.LinterClass((
+            ('rcfile',
+             {'action' : 'callback', 'callback' : lambda *args: 1,
+              'type': 'string', 'metavar': '<file>',
+              'help' : 'Specify a configuration file.'}),
+
+            ('init-hook',
+             {'action' : 'callback', 'type' : 'string', 'metavar': '<code>',
+              'callback' : cb_init_hook, 'level': 1,
+              'help' : 'Python code to execute, usually for sys.path \
+manipulation such as pygtk.require().'}),
+
+            ('help-msg',
+             {'action' : 'callback', 'type' : 'string', 'metavar': '<msg-id>',
+              'callback' : self.cb_help_message,
+              'group': 'Commands',
+              'help' : '''Display a help message for the given message id and \
+exit. The value may be a comma separated list of message ids.'''}),
+
+            ('list-msgs',
+             {'action' : 'callback', 'metavar': '<msg-id>',
+              'callback' : self.cb_list_messages,
+              'group': 'Commands', 'level': 1,
+              'help' : "Generate pylint's messages."}),
+
+            ('full-documentation',
+             {'action' : 'callback', 'metavar': '<msg-id>',
+              'callback' : self.cb_full_documentation,
+              'group': 'Commands', 'level': 1,
+              'help' : "Generate pylint's full documentation."}),
+
+            ('generate-rcfile',
+             {'action' : 'callback', 'callback' : self.cb_generate_config,
+              'group': 'Commands',
+              'help' : '''Generate a sample configuration file according to \
+the current configuration. You can put other options before this one to get \
+them in the generated configuration.'''}),
+
+            ('generate-man',
+             {'action' : 'callback', 'callback' : self.cb_generate_manpage,
+              'group': 'Commands',
+              'help' : "Generate pylint's man page.",'hide': True}),
+
+            ('errors-only',
+             {'action' : 'callback', 'callback' : self.cb_error_mode,
+              'short': 'E',
+              'help' : '''In error mode, checkers without error messages are \
+disabled and for others, only the ERROR messages are displayed, and no reports \
+are done by default'''}),
+
+            ('profile',
+             {'type' : 'yn', 'metavar' : '<y_or_n>',
+              'default': False, 'hide': True,
+              'help' : 'Profiled execution.'}),
+
+            ), option_groups=self.option_groups,
+               reporter=reporter, pylintrc=self._rcfile)
+        # register standard checkers
+        linter.load_default_plugins()
+        # load command line plugins
+        linter.load_plugin_modules(self._plugins)
+        # add some help section
+        linter.add_help_section('Environment variables', config.ENV_HELP, level=1)
+        linter.add_help_section('Output', '''
+Using the default text output, the message format is :                          
+                                                                                
+        MESSAGE_TYPE: LINE_NUM:[OBJECT:] MESSAGE                                
+                                                                                
+There are 5 kind of message types :                                             
+    * (C) convention, for programming standard violation                        
+    * (R) refactor, for bad code smell                                          
+    * (W) warning, for python specific problems                                 
+    * (E) error, for probable bugs in the code                                  
+    * (F) fatal, if an error occurred which prevented pylint from doing further
+processing.
+        ''', level=1)
+        linter.add_help_section('Output status code', '''
+Pylint should leave with following status code:                                 
+    * 0 if everything went fine                                                 
+    * 1 if a fatal message was issued                                           
+    * 2 if an error message was issued                                          
+    * 4 if a warning message was issued                                         
+    * 8 if a refactor message was issued                                        
+    * 16 if a convention message was issued                                     
+    * 32 on usage error                                                         
+                                                                                
+status 1 to 16 will be bit-ORed so you can know which different categories has
+been issued by analysing pylint output status code
+        ''', level=1)
+        # read configuration
+        linter.disable('W0704')
+        linter.read_config_file()
+        # is there some additional plugins in the file configuration, in
+        config_parser = linter.cfgfile_parser
+        if config_parser.has_option('MASTER', 'load-plugins'):
+            plugins = splitstrip(config_parser.get('MASTER', 'load-plugins'))
+            linter.load_plugin_modules(plugins)
+        # now we can load file config and command line, plugins (which can
+        # provide options) have been registered
+        linter.load_config_file()
+        if reporter:
+            # if a custom reporter is provided as argument, it may be overridden
+            # by file parameters, so re-set it here, but before command line
+            # parsing so it's still overrideable by command line option
+            linter.set_reporter(reporter)
+        try:
+            args = linter.load_command_line_configuration(args)
+        except SystemExit, exc:
+            if exc.code == 2: # bad options
+                exc.code = 32
+            raise
+        if not args:
+            print linter.help()
+            sys.exit(32)
+        # insert current working directory to the python path to have a correct
+        # behaviour
+        sys.path.insert(0, os.getcwd())
+        if self.linter.config.profile:
+            print >> sys.stderr, '** profiled run'
+            import cProfile, pstats
+            cProfile.runctx('linter.check(%r)' % args, globals(), locals(), 'stones.prof' )
+            data = pstats.Stats('stones.prof')
+            data.strip_dirs()
+            data.sort_stats('time', 'calls')
+            data.print_stats(30)
+        else:
+            linter.check(args)
+        sys.path.pop(0)
+        if exit:
+            sys.exit(self.linter.msg_status)
+
+    def cb_set_rcfile(self, name, value):
+        """callback for option preprocessing (i.e. before optik parsing)"""
+        self._rcfile = value
+
+    def cb_add_plugins(self, name, value):
+        """callback for option preprocessing (i.e. before optik parsing)"""
+        self._plugins.extend(splitstrip(value))
+
+    def cb_error_mode(self, *args, **kwargs):
+        """error mode:
+        * disable all but error messages
+        * disable the 'miscellaneous' checker which can be safely deactivated in
+          debug
+        * disable reports
+        * do not save execution information
+        """
+        self.linter.error_mode()
+
+    def cb_generate_config(self, *args, **kwargs):
+        """optik callback for sample config file generation"""
+        self.linter.generate_config(skipsections=('COMMANDS',))
+        sys.exit(0)
+
+    def cb_generate_manpage(self, *args, **kwargs):
+        """optik callback for sample config file generation"""
+        from pylint import __pkginfo__
+        self.linter.generate_manpage(__pkginfo__)
+        sys.exit(0)
+
+    def cb_help_message(self, option, optname, value, parser):
+        """optik callback for printing some help about a particular message"""
+        self.linter.help_message(splitstrip(value))
+        sys.exit(0)
+
+    def cb_full_documentation(self, option, optname, value, parser):
+        """optik callback for printing full documentation"""
+        self.linter.print_full_documentation()
+        sys.exit(0)
+
+    def cb_list_messages(self, option, optname, value, parser): # FIXME
+        """optik callback for printing available messages"""
+        self.linter.list_messages()
+        sys.exit(0)
+
+def cb_init_hook(option, optname, value, parser):
+    """exec arbitrary code to set sys.path for instance"""
+    exec value
+
+
+if __name__ == '__main__':
+    Run(sys.argv[1:])