[content/test/gpu] Run pylint check of gpu tests in unittest instead of PRESUBMIT

third_party/pylint/pylint/utils.py

Index: third_party/pylint/pylint/utils.py
diff --git a/third_party/pylint/pylint/utils.py b/third_party/pylint/pylint/utils.py
new file mode 100644
index 0000000000000000000000000000000000000000..6685c4a25d267b592f085198016482f2700b4741
--- /dev/null
+++ b/third_party/pylint/pylint/utils.py
@@ -0,0 +1,919 @@
+# Copyright (c) 2003-2014 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.,
+# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+"""some various utilities and helper classes, most of them used in the
+main pylint class
+"""
+from __future__ import print_function
+
+import collections
+import os
+import re
+import sys
+import tokenize
+import warnings
+from os.path import dirname, basename, splitext, exists, isdir, join, normpath
+
+import six
+from six.moves import zip  # pylint: disable=redefined-builtin
+
+from logilab.common.interface import implements
+from logilab.common.textutils import normalize_text
+from logilab.common.configuration import rest_format_section
+from logilab.common.ureports import Section
+
+from astroid import nodes, Module
+from astroid.modutils import modpath_from_file, get_module_files, \
+    file_from_modpath, load_module_from_file
+
+from pylint.interfaces import IRawChecker, ITokenChecker, UNDEFINED
+
+
+class UnknownMessage(Exception):
+    """raised when a unregistered message id is encountered"""
+
+class EmptyReport(Exception):
+    """raised when a report is empty and so should not be displayed"""
+
+
+MSG_TYPES = {
+    'I' : 'info',
+    'C' : 'convention',
+    'R' : 'refactor',
+    'W' : 'warning',
+    'E' : 'error',
+    'F' : 'fatal'
+    }
+MSG_TYPES_LONG = {v: k for k, v in six.iteritems(MSG_TYPES)}
+
+MSG_TYPES_STATUS = {
+    'I' : 0,
+    'C' : 16,
+    'R' : 8,
+    'W' : 4,
+    'E' : 2,
+    'F' : 1
+    }
+
+_MSG_ORDER = 'EWRCIF'
+MSG_STATE_SCOPE_CONFIG = 0
+MSG_STATE_SCOPE_MODULE = 1
+MSG_STATE_CONFIDENCE = 2
+
+OPTION_RGX = re.compile(r'\s*#.*\bpylint:(.*)')
+
+# The line/node distinction does not apply to fatal errors and reports.
+_SCOPE_EXEMPT = 'FR'
+
+class WarningScope(object):
+    LINE = 'line-based-msg'
+    NODE = 'node-based-msg'
+
+_MsgBase = collections.namedtuple(
+    '_MsgBase',
+    ['msg_id', 'symbol', 'msg', 'C', 'category', 'confidence',
+     'abspath', 'path', 'module', 'obj', 'line', 'column'])
+
+
+class Message(_MsgBase):
+    """This class represent a message to be issued by the reporters"""
+    def __new__(cls, msg_id, symbol, location, msg, confidence):
+        return _MsgBase.__new__(
+            cls, msg_id, symbol, msg, msg_id[0], MSG_TYPES[msg_id[0]],
+            confidence, *location)
+
+    def format(self, template):
+        """Format the message according to the given template.
+
+        The template format is the one of the format method :
+        cf. http://docs.python.org/2/library/string.html#formatstrings
+        """
+        # For some reason, _asdict on derived namedtuples does not work with
+        # Python 3.4. Needs some investigation.
+        return template.format(**dict(zip(self._fields, self)))
+
+
+def get_module_and_frameid(node):
+    """return the module name and the frame id in the module"""
+    frame = node.frame()
+    module, obj = '', []
+    while frame:
+        if isinstance(frame, Module):
+            module = frame.name
+        else:
+            obj.append(getattr(frame, 'name', '<lambda>'))
+        try:
+            frame = frame.parent.frame()
+        except AttributeError:
+            frame = None
+    obj.reverse()
+    return module, '.'.join(obj)
+
+def category_id(cid):
+    cid = cid.upper()
+    if cid in MSG_TYPES:
+        return cid
+    return MSG_TYPES_LONG.get(cid)
+
+
+def _decoding_readline(stream, module):
+    return lambda: stream.readline().decode(module.file_encoding,
+                                           'replace')
+
+
+def tokenize_module(module):
+    with module.stream() as stream:
+        readline = stream.readline
+        if sys.version_info < (3, 0):
+            if module.file_encoding is not None:
+                readline = _decoding_readline(stream, module)
+            return list(tokenize.generate_tokens(readline))
+        return list(tokenize.tokenize(readline))
+
+def build_message_def(checker, msgid, msg_tuple):
+    if implements(checker, (IRawChecker, ITokenChecker)):
+        default_scope = WarningScope.LINE
+    else:
+        default_scope = WarningScope.NODE
+    options = {}
+    if len(msg_tuple) > 3:
+        (msg, symbol, descr, options) = msg_tuple
+    elif len(msg_tuple) > 2:
+        (msg, symbol, descr) = msg_tuple[:3]
+    else:
+        # messages should have a symbol, but for backward compatibility
+        # they may not.
+        (msg, descr) = msg_tuple
+        warnings.warn("[pylint 0.26] description of message %s doesn't include "
+                      "a symbolic name" % msgid, DeprecationWarning)
+        symbol = None
+    options.setdefault('scope', default_scope)
+    return MessageDefinition(checker, msgid, msg, descr, symbol, **options)
+
+
+class MessageDefinition(object):
+    def __init__(self, checker, msgid, msg, descr, symbol, scope,
+                 minversion=None, maxversion=None, old_names=None):
+        self.checker = checker
+        assert len(msgid) == 5, 'Invalid message id %s' % msgid
+        assert msgid[0] in MSG_TYPES, \
+               'Bad message type %s in %r' % (msgid[0], msgid)
+        self.msgid = msgid
+        self.msg = msg
+        self.descr = descr
+        self.symbol = symbol
+        self.scope = scope
+        self.minversion = minversion
+        self.maxversion = maxversion
+        self.old_names = old_names or []
+
+    def may_be_emitted(self):
+        """return True if message may be emitted using the current interpreter"""
+        if self.minversion is not None and self.minversion > sys.version_info:
+            return False
+        if self.maxversion is not None and self.maxversion <= sys.version_info:
+            return False
+        return True
+
+    def format_help(self, checkerref=False):
+        """return the help string for the given message id"""
+        desc = self.descr
+        if checkerref:
+            desc += ' This message belongs to the %s checker.' % \
+                   self.checker.name
+        title = self.msg
+        if self.symbol:
+            msgid = '%s (%s)' % (self.symbol, self.msgid)
+        else:
+            msgid = self.msgid
+        if self.minversion or self.maxversion:
+            restr = []
+            if self.minversion:
+                restr.append('< %s' % '.'.join([str(n) for n in self.minversion]))
+            if self.maxversion:
+                restr.append('>= %s' % '.'.join([str(n) for n in self.maxversion]))
+            restr = ' or '.join(restr)
+            if checkerref:
+                desc += " It can't be emitted when using Python %s." % restr
+            else:
+                desc += " This message can't be emitted when using Python %s." % restr
+        desc = normalize_text(' '.join(desc.split()), indent='  ')
+        if title != '%s':
+            title = title.splitlines()[0]
+            return ':%s: *%s*\n%s' % (msgid, title, desc)
+        return ':%s:\n%s' % (msgid, desc)
+
+
+class MessagesHandlerMixIn(object):
+    """a mix-in class containing all the messages related methods for the main
+    lint class
+    """
+
+    def __init__(self):
+        self._msgs_state = {}
+        self.msg_status = 0
+
+    def disable(self, msgid, scope='package', line=None, ignore_unknown=False):
+        """don't output message of the given id"""
+        assert scope in ('package', 'module')
+        # handle disable=all by disabling all categories
+        if msgid == 'all':
+            for msgid in MSG_TYPES:
+                self.disable(msgid, scope, line)
+            return
+        # msgid is a category?
+        catid = category_id(msgid)
+        if catid is not None:
+            for _msgid in self.msgs_store._msgs_by_category.get(catid):
+                self.disable(_msgid, scope, line)
+            return
+        # msgid is a checker name?
+        if msgid.lower() in self._checkers:
+            msgs_store = self.msgs_store
+            for checker in self._checkers[msgid.lower()]:
+                for _msgid in checker.msgs:
+                    if _msgid in msgs_store._alternative_names:
+                        self.disable(_msgid, scope, line)
+            return
+        # msgid is report id?
+        if msgid.lower().startswith('rp'):
+            self.disable_report(msgid)
+            return
+
+        try:
+            # msgid is a symbolic or numeric msgid.
+            msg = self.msgs_store.check_message_id(msgid)
+        except UnknownMessage:
+            if ignore_unknown:
+                return
+            raise
+
+        if scope == 'module':
+            self.file_state.set_msg_status(msg, line, False)
+            if msg.symbol != 'locally-disabled':
+                self.add_message('locally-disabled', line=line,
+                                 args=(msg.symbol, msg.msgid))
+
+        else:
+            msgs = self._msgs_state
+            msgs[msg.msgid] = False
+            # sync configuration object
+            self.config.disable = [mid for mid, val in six.iteritems(msgs)
+                                   if not val]
+
+    def enable(self, msgid, scope='package', line=None, ignore_unknown=False):
+        """reenable message of the given id"""
+        assert scope in ('package', 'module')
+        catid = category_id(msgid)
+        # msgid is a category?
+        if catid is not None:
+            for msgid in self.msgs_store._msgs_by_category.get(catid):
+                self.enable(msgid, scope, line)
+            return
+        # msgid is a checker name?
+        if msgid.lower() in self._checkers:
+            for checker in self._checkers[msgid.lower()]:
+                for msgid_ in checker.msgs:
+                    self.enable(msgid_, scope, line)
+            return
+        # msgid is report id?
+        if msgid.lower().startswith('rp'):
+            self.enable_report(msgid)
+            return
+
+        try:
+            # msgid is a symbolic or numeric msgid.
+            msg = self.msgs_store.check_message_id(msgid)
+        except UnknownMessage:
+            if ignore_unknown:
+                return
+            raise
+
+        if scope == 'module':
+            self.file_state.set_msg_status(msg, line, True)
+            self.add_message('locally-enabled', line=line, args=(msg.symbol, msg.msgid))
+        else:
+            msgs = self._msgs_state
+            msgs[msg.msgid] = True
+            # sync configuration object
+            self.config.enable = [mid for mid, val in six.iteritems(msgs) if val]
+
+    def get_message_state_scope(self, msgid, line=None, confidence=UNDEFINED):
+        """Returns the scope at which a message was enabled/disabled."""
+        if self.config.confidence and confidence.name not in self.config.confidence:
+            return MSG_STATE_CONFIDENCE
+        try:
+            if line in self.file_state._module_msgs_state[msgid]:
+                return MSG_STATE_SCOPE_MODULE
+        except (KeyError, TypeError):
+            return MSG_STATE_SCOPE_CONFIG
+
+    def is_message_enabled(self, msg_descr, line=None, confidence=None):
+        """return true if the message associated to the given message id is
+        enabled
+
+        msgid may be either a numeric or symbolic message id.
+        """
+        if self.config.confidence and confidence:
+            if confidence.name not in self.config.confidence:
+                return False
+        try:
+            msgid = self.msgs_store.check_message_id(msg_descr).msgid
+        except UnknownMessage:
+            # The linter checks for messages that are not registered
+            # due to version mismatch, just treat them as message IDs
+            # for now.
+            msgid = msg_descr
+        if line is None:
+            return self._msgs_state.get(msgid, True)
+        try:
+            return self.file_state._module_msgs_state[msgid][line]
+        except KeyError:
+            return self._msgs_state.get(msgid, True)
+
+    def add_message(self, msg_descr, line=None, node=None, args=None, confidence=UNDEFINED):
+        """Adds a message given by ID or name.
+
+        If provided, the message string is expanded using args
+
+        AST checkers should must the node argument (but may optionally
+        provide line if the line number is different), raw and token checkers
+        must provide the line argument.
+        """
+        msg_info = self.msgs_store.check_message_id(msg_descr)
+        msgid = msg_info.msgid
+        # backward compatibility, message may not have a symbol
+        symbol = msg_info.symbol or msgid
+        # Fatal messages and reports are special, the node/scope distinction
+        # does not apply to them.
+        if msgid[0] not in _SCOPE_EXEMPT:
+            if msg_info.scope == WarningScope.LINE:
+                assert node is None and line is not None, (
+                    'Message %s must only provide line, got line=%s, node=%s' % (msgid, line, node))
+            elif msg_info.scope == WarningScope.NODE:
+                # Node-based warnings may provide an override line.
+                assert node is not None, 'Message %s must provide Node, got None'
+
+        if line is None and node is not None:
+            line = node.fromlineno
+        if hasattr(node, 'col_offset'):
+            col_offset = node.col_offset # XXX measured in bytes for utf-8, divide by two for chars?
+        else:
+            col_offset = None
+        # should this message be displayed
+        if not self.is_message_enabled(msgid, line, confidence):
+            self.file_state.handle_ignored_message(
+                self.get_message_state_scope(msgid, line, confidence),
+                msgid, line, node, args, confidence)
+            return
+        # update stats
+        msg_cat = MSG_TYPES[msgid[0]]
+        self.msg_status |= MSG_TYPES_STATUS[msgid[0]]
+        self.stats[msg_cat] += 1
+        self.stats['by_module'][self.current_name][msg_cat] += 1
+        try:
+            self.stats['by_msg'][symbol] += 1
+        except KeyError:
+            self.stats['by_msg'][symbol] = 1
+        # expand message ?
+        msg = msg_info.msg
+        if args:
+            msg %= args
+        # get module and object
+        if node is None:
+            module, obj = self.current_name, ''
+            abspath = self.current_file
+        else:
+            module, obj = get_module_and_frameid(node)
+            abspath = node.root().file
+        path = abspath.replace(self.reporter.path_strip_prefix, '')
+        # add the message
+        self.reporter.handle_message(
+            Message(msgid, symbol,
+                    (abspath, path, module, obj, line or 1, col_offset or 0), msg, confidence))
+
+    def print_full_documentation(self):
+        """output a full documentation in ReST format"""
+        print("Pylint global options and switches")
+        print("----------------------------------")
+        print("")
+        print("Pylint provides global options and switches.")
+        print("")
+
+        by_checker = {}
+        for checker in self.get_checkers():
+            if checker.name == 'master':
+                if checker.options:
+                    for section, options in checker.options_by_section():
+                        if section is None:
+                            title = 'General options'
+                        else:
+                            title = '%s options' % section.capitalize()
+                        print(title)
+                        print('~' * len(title))
+                        rest_format_section(sys.stdout, None, options)
+                        print("")
+            else:
+                try:
+                    by_checker[checker.name][0] += checker.options_and_values()
+                    by_checker[checker.name][1].update(checker.msgs)
+                    by_checker[checker.name][2] += checker.reports
+                except KeyError:
+                    by_checker[checker.name] = [list(checker.options_and_values()),
+                                                dict(checker.msgs),
+                                                list(checker.reports)]
+
+        print("Pylint checkers' options and switches")
+        print("-------------------------------------")
+        print("")
+        print("Pylint checkers can provide three set of features:")
+        print("")
+        print("* options that control their execution,")
+        print("* messages that they can raise,")
+        print("* reports that they can generate.")
+        print("")
+        print("Below is a list of all checkers and their features.")
+        print("")
+
+        for checker, (options, msgs, reports) in six.iteritems(by_checker):
+            title = '%s checker' % (checker.replace("_", " ").title())
+            print(title)
+            print('~' * len(title))
+            print("")
+            print("Verbatim name of the checker is ``%s``." % checker)
+            print("")
+            if options:
+                title = 'Options'
+                print(title)
+                print('^' * len(title))
+                rest_format_section(sys.stdout, None, options)
+                print("")
+            if msgs:
+                title = 'Messages'
+                print(title)
+                print('~' * len(title))
+                for msgid, msg in sorted(six.iteritems(msgs),
+                                         key=lambda kv: (_MSG_ORDER.index(kv[0][0]), kv[1])):
+                    msg = build_message_def(checker, msgid, msg)
+                    print(msg.format_help(checkerref=False))
+                print("")
+            if reports:
+                title = 'Reports'
+                print(title)
+                print('~' * len(title))
+                for report in reports:
+                    print(':%s: %s' % report[:2])
+                print("")
+            print("")
+
+
+class FileState(object):
+    """Hold internal state specific to the currently analyzed file"""
+
+    def __init__(self, modname=None):
+        self.base_name = modname
+        self._module_msgs_state = {}
+        self._raw_module_msgs_state = {}
+        self._ignored_msgs = collections.defaultdict(set)
+        self._suppression_mapping = {}
+
+    def collect_block_lines(self, msgs_store, module_node):
+        """Walk the AST to collect block level options line numbers."""
+        for msg, lines in six.iteritems(self._module_msgs_state):
+            self._raw_module_msgs_state[msg] = lines.copy()
+        orig_state = self._module_msgs_state.copy()
+        self._module_msgs_state = {}
+        self._suppression_mapping = {}
+        self._collect_block_lines(msgs_store, module_node, orig_state)
+
+    def _collect_block_lines(self, msgs_store, node, msg_state):
+        """Recursivly walk (depth first) AST to collect block level options line
+        numbers.
+        """
+        for child in node.get_children():
+            self._collect_block_lines(msgs_store, 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 six.iteritems(msg_state):
+            for lineno, state in list(lines.items()):
+                original_lineno = lineno
+                if first <= lineno <= last:
+                    # Set state for all lines for this block, if the
+                    # warning is applied to nodes.
+                    if  msgs_store.check_message_id(msgid).scope == WarningScope.NODE:
+                        if lineno > firstchildlineno:
+                            state = True
+                        first_, last_ = node.block_range(lineno)
+                    else:
+                        first_ = lineno
+                        last_ = last
+                    for line in range(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]
+                                original_lineno = line
+                            if not state:
+                                self._suppression_mapping[(msgid, line)] = original_lineno
+                            try:
+                                self._module_msgs_state[msgid][line] = state
+                            except KeyError:
+                                self._module_msgs_state[msgid] = {line: state}
+                    del lines[lineno]
+
+    def set_msg_status(self, msg, line, status):
+        """Set status (enabled/disable) for a given message at a given line"""
+        assert line > 0
+        try:
+            self._module_msgs_state[msg.msgid][line] = status
+        except KeyError:
+            self._module_msgs_state[msg.msgid] = {line: status}
+
+    def handle_ignored_message(self, state_scope, msgid, line,
+                               node, args, confidence): # pylint: disable=unused-argument
+        """Report an ignored message.
+
+        state_scope is either MSG_STATE_SCOPE_MODULE or MSG_STATE_SCOPE_CONFIG,
+        depending on whether the message was disabled locally in the module,
+        or globally. The other arguments are the same as for add_message.
+        """
+        if state_scope == MSG_STATE_SCOPE_MODULE:
+            try:
+                orig_line = self._suppression_mapping[(msgid, line)]
+                self._ignored_msgs[(msgid, orig_line)].add(line)
+            except KeyError:
+                pass
+
+    def iter_spurious_suppression_messages(self, msgs_store):
+        for warning, lines in six.iteritems(self._raw_module_msgs_state):
+            for line, enable in six.iteritems(lines):
+                if not enable and (warning, line) not in self._ignored_msgs:
+                    yield 'useless-suppression', line, \
+                        (msgs_store.get_msg_display_string(warning),)
+        # don't use iteritems here, _ignored_msgs may be modified by add_message
+        for (warning, from_), lines in list(self._ignored_msgs.items()):
+            for line in lines:
+                yield 'suppressed-message', line, \
+                    (msgs_store.get_msg_display_string(warning), from_)
+
+
+class MessagesStore(object):
+    """The messages store knows information about every possible message but has
+    no particular state during analysis.
+    """
+
+    def __init__(self):
+        # Primary registry for all active messages (i.e. all messages
+        # that can be emitted by pylint for the underlying Python
+        # version). It contains the 1:1 mapping from symbolic names
+        # to message definition objects.
+        self._messages = {}
+        # Maps alternative names (numeric IDs, deprecated names) to
+        # message definitions. May contain several names for each definition
+        # object.
+        self._alternative_names = {}
+        self._msgs_by_category = collections.defaultdict(list)
+
+    @property
+    def messages(self):
+        """The list of all active messages."""
+        return six.itervalues(self._messages)
+
+    def add_renamed_message(self, old_id, old_symbol, new_symbol):
+        """Register the old ID and symbol for a warning that was renamed.
+
+        This allows users to keep using the old ID/symbol in suppressions.
+        """
+        msg = self.check_message_id(new_symbol)
+        msg.old_names.append((old_id, old_symbol))
+        self._alternative_names[old_id] = msg
+        self._alternative_names[old_symbol] = msg
+
+    def register_messages(self, checker):
+        """register a dictionary of messages
+
+        Keys are message ids, values are a 2-uple with the message type and the
+        message itself
+
+        message ids should be a string of len 4, where the two first characters
+        are the checker id and the two last the message id in this checker
+        """
+        chkid = None
+        for msgid, msg_tuple in six.iteritems(checker.msgs):
+            msg = build_message_def(checker, msgid, msg_tuple)
+            assert msg.symbol not in self._messages, \
+                    'Message symbol %r is already defined' % msg.symbol
+            # avoid duplicate / malformed ids
+            assert msg.msgid not in self._alternative_names, \
+                   'Message id %r is already defined' % msgid
+            assert chkid is None or chkid == msg.msgid[1:3], \
+                   'Inconsistent checker part in message id %r' % msgid
+            chkid = msg.msgid[1:3]
+            self._messages[msg.symbol] = msg
+            self._alternative_names[msg.msgid] = msg
+            for old_id, old_symbol in msg.old_names:
+                self._alternative_names[old_id] = msg
+                self._alternative_names[old_symbol] = msg
+            self._msgs_by_category[msg.msgid[0]].append(msg.msgid)
+
+    def check_message_id(self, msgid):
+        """returns the Message object for this message.
+
+        msgid may be either a numeric or symbolic id.
+
+        Raises UnknownMessage if the message id is not defined.
+        """
+        if msgid[1:].isdigit():
+            msgid = msgid.upper()
+        for source in (self._alternative_names, self._messages):
+            try:
+                return source[msgid]
+            except KeyError:
+                pass
+        raise UnknownMessage('No such message id %s' % msgid)
+
+    def get_msg_display_string(self, msgid):
+        """Generates a user-consumable representation of a message.
+
+        Can be just the message ID or the ID and the symbol.
+        """
+        return repr(self.check_message_id(msgid).symbol)
+
+    def help_message(self, msgids):
+        """display help messages for the given message identifiers"""
+        for msgid in msgids:
+            try:
+                print(self.check_message_id(msgid).format_help(checkerref=True))
+                print("")
+            except UnknownMessage as ex:
+                print(ex)
+                print("")
+                continue
+
+    def list_messages(self):
+        """output full messages list documentation in ReST format"""
+        msgs = sorted(six.itervalues(self._messages), key=lambda msg: msg.msgid)
+        for msg in msgs:
+            if not msg.may_be_emitted():
+                continue
+            print(msg.format_help(checkerref=False))
+        print("")
+
+
+class ReportsHandlerMixIn(object):
+    """a mix-in class containing all the reports and stats manipulation
+    related methods for the main lint class
+    """
+    def __init__(self):
+        self._reports = collections.defaultdict(list)
+        self._reports_state = {}
+
+    def report_order(self):
+        """ Return a list of reports, sorted in the order
+        in which they must be called.
+        """
+        return list(self._reports)
+
+    def register_report(self, reportid, r_title, r_cb, checker):
+        """register a report
+
+        reportid is the unique identifier for the report
+        r_title the report's title
+        r_cb the method to call to make the report
+        checker is the checker defining the report
+        """
+        reportid = reportid.upper()
+        self._reports[checker].append((reportid, r_title, r_cb))
+
+    def enable_report(self, reportid):
+        """disable the report of the given id"""
+        reportid = reportid.upper()
+        self._reports_state[reportid] = True
+
+    def disable_report(self, reportid):
+        """disable the report of the given id"""
+        reportid = reportid.upper()
+        self._reports_state[reportid] = False
+
+    def report_is_enabled(self, reportid):
+        """return true if the report associated to the given identifier is
+        enabled
+        """
+        return self._reports_state.get(reportid, True)
+
+    def make_reports(self, stats, old_stats):
+        """render registered reports"""
+        sect = Section('Report',
+                       '%s statements analysed.'% (self.stats['statement']))
+        for checker in self.report_order():
+            for reportid, r_title, r_cb in self._reports[checker]:
+                if not self.report_is_enabled(reportid):
+                    continue
+                report_sect = Section(r_title)
+                try:
+                    r_cb(report_sect, stats, old_stats)
+                except EmptyReport:
+                    continue
+                report_sect.report_id = reportid
+                sect.append(report_sect)
+        return sect
+
+    def add_stats(self, **kwargs):
+        """add some stats entries to the statistic dictionary
+        raise an AssertionError if there is a key conflict
+        """
+        for key, value in six.iteritems(kwargs):
+            if key[-1] == '_':
+                key = key[:-1]
+            assert key not in self.stats
+            self.stats[key] = value
+        return self.stats
+
+
+def expand_modules(files_or_modules, black_list):
+    """take a list of files/modules/packages and return the list of tuple
+    (file, module name) which have to be actually checked
+    """
+    result = []
+    errors = []
+    for something in files_or_modules:
+        if exists(something):
+            # this is a file or a directory
+            try:
+                modname = '.'.join(modpath_from_file(something))
+            except ImportError:
+                modname = splitext(basename(something))[0]
+            if isdir(something):
+                filepath = join(something, '__init__.py')
+            else:
+                filepath = something
+        else:
+            # suppose it's a module or package
+            modname = something
+            try:
+                filepath = file_from_modpath(modname.split('.'))
+                if filepath is None:
+                    errors.append({'key' : 'ignored-builtin-module', 'mod': modname})
+                    continue
+            except (ImportError, SyntaxError) as ex:
+                # FIXME p3k : the SyntaxError is a Python bug and should be
+                # removed as soon as possible http://bugs.python.org/issue10588
+                errors.append({'key': 'fatal', 'mod': modname, 'ex': ex})
+                continue
+        filepath = normpath(filepath)
+        result.append({'path': filepath, 'name': modname, 'isarg': True,
+                       'basepath': filepath, 'basename': modname})
+        if not (modname.endswith('.__init__') or modname == '__init__') \
+                and '__init__.py' in filepath:
+            for subfilepath in get_module_files(dirname(filepath), black_list):
+                if filepath == subfilepath:
+                    continue
+                submodname = '.'.join(modpath_from_file(subfilepath))
+                result.append({'path': subfilepath, 'name': submodname,
+                               'isarg': False,
+                               'basepath': filepath, 'basename': modname})
+    return result, errors
+
+
+class PyLintASTWalker(object):
+
+    def __init__(self, linter):
+        # callbacks per node types
+        self.nbstatements = 1
+        self.visit_events = collections.defaultdict(list)
+        self.leave_events = collections.defaultdict(list)
+        self.linter = linter
+
+    def _is_method_enabled(self, method):
+        if not hasattr(method, 'checks_msgs'):
+            return True
+        for msg_desc in method.checks_msgs:
+            if self.linter.is_message_enabled(msg_desc):
+                return True
+        return False
+
+    def add_checker(self, checker):
+        """walk to the checker's dir and collect visit and leave methods"""
+        # XXX : should be possible to merge needed_checkers and add_checker
+        vcids = set()
+        lcids = set()
+        visits = self.visit_events
+        leaves = self.leave_events
+        for member in dir(checker):
+            cid = member[6:]
+            if cid == 'default':
+                continue
+            if member.startswith('visit_'):
+                v_meth = getattr(checker, member)
+                # don't use visit_methods with no activated message:
+                if self._is_method_enabled(v_meth):
+                    visits[cid].append(v_meth)
+                    vcids.add(cid)
+            elif member.startswith('leave_'):
+                l_meth = getattr(checker, member)
+                # don't use leave_methods with no activated message:
+                if self._is_method_enabled(l_meth):
+                    leaves[cid].append(l_meth)
+                    lcids.add(cid)
+        visit_default = getattr(checker, 'visit_default', None)
+        if visit_default:
+            for cls in nodes.ALL_NODE_CLASSES:
+                cid = cls.__name__.lower()
+                if cid not in vcids:
+                    visits[cid].append(visit_default)
+        # for now we have no "leave_default" method in Pylint
+
+    def walk(self, astroid):
+        """call visit events of astroid checkers for the given node, recurse on
+        its children, then leave events.
+        """
+        cid = astroid.__class__.__name__.lower()
+        if astroid.is_statement:
+            self.nbstatements += 1
+        # generate events for this node on each checker
+        for cb in self.visit_events.get(cid, ()):
+            cb(astroid)
+        # recurse on children
+        for child in astroid.get_children():
+            self.walk(child)
+        for cb in self.leave_events.get(cid, ()):
+            cb(astroid)
+
+
+PY_EXTS = ('.py', '.pyc', '.pyo', '.pyw', '.so', '.dll')
+
+def register_plugins(linter, directory):
+    """load all module and package in the given directory, looking for a
+    'register' function in each one, used to register pylint checkers
+    """
+    imported = {}
+    for filename in os.listdir(directory):
+        base, extension = splitext(filename)
+        if base in imported or base == '__pycache__':
+            continue
+        if extension in PY_EXTS and base != '__init__' or (
+                not extension and isdir(join(directory, base))):
+            try:
+                module = load_module_from_file(join(directory, filename))
+            except ValueError:
+                # empty module name (usually emacs auto-save files)
+                continue
+            except ImportError as exc:
+                print("Problem importing module %s: %s" % (filename, exc),
+                      file=sys.stderr)
+            else:
+                if hasattr(module, 'register'):
+                    module.register(linter)
+                    imported[base] = 1
+
+def get_global_option(checker, option, default=None):
+    """ Retrieve an option defined by the given *checker* or
+    by all known option providers.
+
+    It will look in the list of all options providers
+    until the given *option* will be found.
+    If the option wasn't found, the *default* value will be returned.
+    """
+    # First, try in the given checker's config.
+    # After that, look in the options providers.
+
+    try:
+        return getattr(checker.config, option.replace("-", "_"))
+    except AttributeError:
+        pass
+    for provider in checker.linter.options_providers:
+        for options in provider.options:
+            if options[0] == option:
+                return getattr(provider.config, option.replace("-", "_"))
+    return default