pylint: upgrade to 1.4.0

third_party/pylint/checkers/stdlib.py

 # Copyright 2012 Google Inc.
 #
 # 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.
 """Checkers for various standard library functions."""
 
 import re
 import sys
 
 import astroid
+from astroid.bases import Instance
 
 from pylint.interfaces import IAstroidChecker
 from pylint.checkers import BaseChecker
 from pylint.checkers import utils
 
 _VALID_OPEN_MODE_REGEX = re.compile(r'^(r?U|[rwa]\+?b?)$')
 
 if sys.version_info >= (3, 0):
     OPEN_MODULE = '_io'
 else:
     OPEN_MODULE = '__builtin__'
 
-class OpenModeChecker(BaseChecker):
+class StdlibChecker(BaseChecker):
     __implements__ = (IAstroidChecker,)
-    name = 'open_mode'
+    name = 'stdlib'
 
     msgs = {
         'W1501': ('"%s" is not a valid mode for open.',
                   'bad-open-mode',
                   'Python supports: r, w, a modes with b, +, and U options. '
                   'See http://docs.python.org/2/library/functions.html#open'),
+        'W1502': ('Using datetime.time in a boolean context.',
+                  'boolean-datetime',
+                  'Using datetetime.time in a boolean context can hide '
+                  'subtle bugs when the time they represent matches '
+                  'midnight UTC. This behaviour was fixed in Python 3.5. '
+                  'See http://bugs.python.org/issue13936 for reference.',
+                  {'maxversion': (3, 5)}),
         }
 
     @utils.check_messages('bad-open-mode')
     def visit_callfunc(self, node):
         """Visit a CallFunc node."""
         if hasattr(node, 'func'):
             infer = utils.safe_infer(node.func)
             if infer and infer.root().name == OPEN_MODULE:
                 if getattr(node.func, 'name', None) in ('open', 'file'):
                     self._check_open_mode(node)
 
+    @utils.check_messages('boolean-datetime')
+    def visit_unaryop(self, node):
+        if node.op == 'not':
+            self._check_datetime(node.operand)
+
+    @utils.check_messages('boolean-datetime')
+    def visit_if(self, node):
+        self._check_datetime(node.test)
+
+    @utils.check_messages('boolean-datetime')
+    def visit_ifexp(self, node):
+        self._check_datetime(node.test)
+
+    @utils.check_messages('boolean-datetime')
+    def visit_boolop(self, node):
+        for value in node.values:
+            self._check_datetime(value)
+
+    def _check_datetime(self, node):
+        """ Check that a datetime was infered.
+        If so, emit boolean-datetime warning.
+        """
+        try:
+            infered = next(node.infer())
+        except astroid.InferenceError:
+            return
+        if (isinstance(infered, Instance) and
+                infered.qname() == 'datetime.time'):
+            self.add_message('boolean-datetime', node=node)
+
     def _check_open_mode(self, node):
         """Check that the mode argument of an open or file call is valid."""
         try:
             mode_arg = utils.get_argument_from_call(node, position=1, keyword='mode')
             if mode_arg:
                 mode_arg = utils.safe_infer(mode_arg)
                 if (isinstance(mode_arg, astroid.Const)
                         and not _VALID_OPEN_MODE_REGEX.match(mode_arg.value)):
                     self.add_message('bad-open-mode', node=node,
                                      args=(mode_arg.value))
         except (utils.NoSuchArgumentError, TypeError):
             pass
 
 def register(linter):
     """required method to auto register this checker """
-    linter.register_checker(OpenModeChecker(linter))
+    linter.register_checker(StdlibChecker(linter))