Move all package files to a pylint package.

1 files changed, 173 insertions, 0 deletions

diff --git a/pylint/checkers/stdlib.py b/pylint/checkers/stdlib.py
new file mode 100644
index 0000000..b6b8026
--- /dev/null
+++ b/pylint/checkers/stdlib.py
@@ -0,0 +1,173 @@
+# 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 six
+import sys
+
+import astroid
+from astroid.bases import Instance
+
+from pylint.interfaces import IAstroidChecker
+from pylint.checkers import BaseChecker
+from pylint.checkers import utils
+
+
+if sys.version_info >= (3, 0):
+    OPEN_MODULE = '_io'
+else:
+    OPEN_MODULE = '__builtin__'
+
+
+def _check_mode_str(mode):
+    # check type
+    if not isinstance(mode, six.string_types):
+        return False
+    # check syntax
+    modes = set(mode)
+    _mode = "rwatb+U"
+    creating = False
+    if six.PY3:
+        _mode += "x"
+        creating = "x" in modes
+    if modes - set(_mode) or len(mode) > len(modes):
+        return False
+    # check logic
+    reading = "r" in modes
+    writing = "w" in modes
+    appending = "a" in modes
+    updating = "+" in modes
+    text = "t" in modes
+    binary = "b" in modes
+    if "U" in modes:
+        if writing or appending or creating and six.PY3:
+            return False
+        reading = True
+        if not six.PY3:
+            binary = True
+    if text and binary:
+        return False
+    total = reading + writing + appending + (creating if six.PY3 else 0)
+    if total > 1:
+        return False
+    if not (reading or writing or appending or creating and six.PY3):
+        return False
+    # other 2.x constraints
+    if not six.PY3:
+        if "U" in mode:
+            mode = mode.replace("U", "")
+            if "r" not in mode:
+                mode = "r" + mode
+        return mode[0] in ("r", "w", "a", "U")
+    return True
+
+
+class StdlibChecker(BaseChecker):
+    __implements__ = (IAstroidChecker,)
+    name = 'stdlib'
+
+    msgs = {
+        'W1501': ('"%s" is not a valid mode for open.',
+                  'bad-open-mode',
+                  'Python supports: r, w, a[, x] modes with b, +, '
+                  'and U (only with r) 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)}),
+        'W1503': ('Redundant use of %s with constant '
+                  'value %r',
+                  'redundant-unittest-assert',
+                  'The first argument of assertTrue and assertFalse is'
+                  'a condition. If a constant is passed as parameter, that'
+                  'condition will be always true. In this case a warning '
+                  'should be emitted.')
+    }
+
+    @utils.check_messages('bad-open-mode', 'redundant-unittest-assert')
+    def visit_callfunc(self, node):
+        """Visit a CallFunc node."""
+        if hasattr(node, 'func'):
+            infer = utils.safe_infer(node.func)
+            if infer:
+                if infer.root().name == OPEN_MODULE:
+                    if getattr(node.func, 'name', None) in ('open', 'file'):
+                        self._check_open_mode(node)
+                if infer.root().name == 'unittest.case':
+                    self._check_redundant_assert(node, infer)
+
+    @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_redundant_assert(self, node, infer):
+        if (isinstance(infer, astroid.BoundMethod) and
+                node.args and isinstance(node.args[0], astroid.Const) and
+                infer.name in ['assertTrue', 'assertFalse']):
+            self.add_message('redundant-unittest-assert',
+                             args=(infer.name, node.args[0].value, ),
+                             node=node)
+
+    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')
+        except utils.NoSuchArgumentError:
+            return
+        if mode_arg:
+            mode_arg = utils.safe_infer(mode_arg)
+            if (isinstance(mode_arg, astroid.Const)
+                    and not _check_mode_str(mode_arg.value)):
+                self.add_message('bad-open-mode', node=node,
+                                 args=mode_arg.value)
+
+
+def register(linter):
+    """required method to auto register this checker """
+    linter.register_checker(StdlibChecker(linter))