Merged in mibalint/pylint (pull request #234)

#422 [pylint sprint] Create pylintrc and disable checking for all issues

11 files changed, 200 insertions, 57 deletions

diff --git a/ChangeLog b/ChangeLog
index 9977d16..30a2d28 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,7 +1,7 @@
 ChangeLog for Pylint
 --------------------
 
-NOT RELEASED YET -- VERSION
+RELEASE DATE -- VERSION
     * Don't require a docstring for empty modules. Closes issue #261.
 
     * Fix a false positive with `too-few-format-args` string warning,
@@ -44,6 +44,14 @@ NOT RELEASED YET -- VERSION
     * Add support for combining the Python 3 checker mode with the --jobs
       flag (--py3k and --jobs). Closes issue #467.
 
+    * Add a new warning for the Python 3 porting checker, 'using-cmp-argument',
+      emitted when the `cmp` argument for the `list.sort` or `sorted builtin`
+      is encountered.
+
+    * Make the --py3k flag commutative with the -E flag. Also, this patch
+      fixes the leaks of error messages from the Python 3 checker when
+      the errors mode was activated. Closes issue #437.
+
 
 2015-01-16 -- 1.4.1
 
@@ -315,9 +323,9 @@ NOT RELEASED YET -- VERSION
       the 'a' format on Python 3.
 
     * Add multiple checks for PEP 3101 advanced string formatting:
-     'bad-format-string', 'missing-format-argument-key',
-     'unused-format-string-argument', 'format-combined-specification',
-     'missing-format-attribute' and 'invalid-format-index'.
+      'bad-format-string', 'missing-format-argument-key',
+      'unused-format-string-argument', 'format-combined-specification',
+      'missing-format-attribute' and 'invalid-format-index'.
 
     * Issue broad-except and bare-except even if the number
       of except handlers is different than 1. Fixes issue #113.
@@ -477,7 +485,7 @@ NOT RELEASED YET -- VERSION
       Golemon
 
     * Add new warnings for checking proper class __slots__:
-     `invalid-slots-object` and `invalid-slots`.
+      `invalid-slots-object` and `invalid-slots`.
 
     * Search for rc file in `~/.config/pylintrc` if `~/.pylintrc`
       doesn't exists (#121)
@@ -799,10 +807,10 @@ NOT RELEASED YET -- VERSION
       (patch by tmarek@google.com)
 
     * #7394: W0212 (access to protected member) not emited on assigments
-    (patch by lothiraldan@gmail.com)
+      (patch by lothiraldan@gmail.com)
 
     * #18772; no prototype consistency check for mangled methods (patch by
-    lothiraldan@gmail.com)
+      lothiraldan@gmail.com)
 
     * #92911: emit W0102 when sets are used as default arguments in functions
       (patch by tmarek@google.com)
diff --git a/doc/Makefile b/doc/Makefile
index d483f63..2cd7f7e 100644
--- a/doc/Makefile
+++ b/doc/Makefile
@@ -6,6 +6,7 @@ SPHINXOPTS    =
 SPHINXBUILD   = sphinx-build
 PAPER         =
 BUILDDIR      = _build
+PYTHONPATH    =
 
 # Internal variables.
 PAPEROPT_a4     = -D latex_paper_size=a4
@@ -138,7 +139,7 @@ features:
 	echo "" >> features.rst
 	echo ".. generated by pylint --full-documentation" >> features.rst
 	echo "" >> features.rst
-	pylint --full-documentation >> features.rst
+	PYTHONPATH=$(PYTHONPATH) pylint --full-documentation >> features.rst
 
 gen-examples:
 	chmod u+w ../examples/pylintrc
diff --git a/doc/index.rst b/doc/index.rst
index 01f44c8..d67a28d 100644
--- a/doc/index.rst
+++ b/doc/index.rst
@@ -12,7 +12,7 @@ https://bitbucket.org/logilab/pylint
    run
    output
    message-control
-   features
+   features1
    options
    extend
    ide-integration
diff --git a/pylint/checkers/classes.py b/pylint/checkers/classes.py
index 8e51a47..87e3bcf 100644
--- a/pylint/checkers/classes.py
+++ b/pylint/checkers/classes.py
@@ -107,9 +107,9 @@ def _is_attribute_property(name, klass):
 MSGS = {
     'F0202': ('Unable to check methods signature (%s / %s)',
               'method-check-failed',
-              'Used when Pylint has been unable to check methods signature \
-              compatibility for an unexpected reason. Please report this kind \
-              if you don\'t make sense of it.'),
+              'Used when Pylint has been unable to check methods signature '
+              'compatibility for an unexpected reason. Please report this kind '
+              'if you don\'t make sense of it.'),
 
     'E0202': ('An attribute defined in %s line %s hides this method',
               'method-hidden',
@@ -118,35 +118,35 @@ MSGS = {
               'client code.'),
     'E0203': ('Access to member %r before its definition line %s',
               'access-member-before-definition',
-              'Used when an instance member is accessed before it\'s actually\
-              assigned.'),
+              'Used when an instance member is accessed before it\'s actually '
+              'assigned.'),
     'W0201': ('Attribute %r defined outside __init__',
               'attribute-defined-outside-init',
-              'Used when an instance attribute is defined outside the __init__\
-              method.'),
+              'Used when an instance attribute is defined outside the __init__ '
+              'method.'),
 
     'W0212': ('Access to a protected member %s of a client class', # E0214
               'protected-access',
-              'Used when a protected member (i.e. class member with a name \
-              beginning with an underscore) is access outside the class or a \
-              descendant of the class where it\'s defined.'),
+              'Used when a protected member (i.e. class member with a name '
+              'beginning with an underscore) is access outside the class or a '
+              'descendant of the class where it\'s defined.'),
 
     'E0211': ('Method has no argument',
               'no-method-argument',
-              'Used when a method which should have the bound instance as \
-              first argument has no argument defined.'),
+              'Used when a method which should have the bound instance as '
+              'first argument has no argument defined.'),
     'E0213': ('Method should have "self" as first argument',
               'no-self-argument',
-              'Used when a method has an attribute different the "self" as\
-              first argument. This is considered as an error since this is\
-              a so common convention that you shouldn\'t break it!'),
-    'C0202': ('Class method %s should have %s as first argument', # E0212
+              'Used when a method has an attribute different the "self" as '
+              'first argument. This is considered as an error since this is '
+              'a so common convention that you shouldn\'t break it!'),
+    'C0202': ('Class method %s should have %s as first argument',
               'bad-classmethod-argument',
               'Used when a class method has a first argument named differently '
               'than the value specified in valid-classmethod-first-arg option '
               '(default to "cls"), recommended to easily differentiate them '
               'from regular instance methods.'),
-    'C0203': ('Metaclass method %s should have %s as first argument', # E0214
+    'C0203': ('Metaclass method %s should have %s as first argument',
               'bad-mcs-method-argument',
               'Used when a metaclass method has a first agument named '
               'differently than the value specified in valid-classmethod-first'
@@ -167,58 +167,58 @@ MSGS = {
              ),
     'R0201': ('Method could be a function',
               'no-self-use',
-              'Used when a method doesn\'t use its bound instance, and so could\
-              be written as a function.'
+              'Used when a method doesn\'t use its bound instance, and so could '
+              'be written as a function.'
              ),
 
     'E0221': ('Interface resolved to %s is not a class',
               'interface-is-not-class',
-              'Used when a class claims to implement an interface which is not \
-              a class.'),
+              'Used when a class claims to implement an interface which is not '
+              'a class.'),
     'E0222': ('Missing method %r from %s interface',
               'missing-interface-method',
-              'Used when a method declared in an interface is missing from a \
-              class implementing this interface'),
+              'Used when a method declared in an interface is missing from a '
+              'class implementing this interface'),
     'W0221': ('Arguments number differs from %s %r method',
               'arguments-differ',
-              'Used when a method has a different number of arguments than in \
-              the implemented interface or in an overridden method.'),
+              'Used when a method has a different number of arguments than in '
+              'the implemented interface or in an overridden method.'),
     'W0222': ('Signature differs from %s %r method',
               'signature-differs',
-              'Used when a method signature is different than in the \
-              implemented interface or in an overridden method.'),
+              'Used when a method signature is different than in the '
+              'implemented interface or in an overridden method.'),
     'W0223': ('Method %r is abstract in class %r but is not overridden',
               'abstract-method',
-              'Used when an abstract method (i.e. raise NotImplementedError) is \
-              not overridden in concrete class.'
+              'Used when an abstract method (i.e. raise NotImplementedError) is '
+              'not overridden in concrete class.'
              ),
-    'F0220': ('failed to resolve interfaces implemented by %s (%s)', # W0224
+    'F0220': ('failed to resolve interfaces implemented by %s (%s)',
               'unresolved-interface',
-              'Used when a Pylint as failed to find interfaces implemented by \
-               a class'),
+              'Used when a Pylint as failed to find interfaces implemented by '
+              ' a class'),
 
 
     'W0231': ('__init__ method from base class %r is not called',
               'super-init-not-called',
-              'Used when an ancestor class method has an __init__ method \
-              which is not called by a derived class.'),
+              'Used when an ancestor class method has an __init__ method '
+              'which is not called by a derived class.'),
     'W0232': ('Class has no __init__ method',
               'no-init',
-              'Used when a class has no __init__ method, neither its parent \
-              classes.'),
+              'Used when a class has no __init__ method, neither its parent '
+              'classes.'),
     'W0233': ('__init__ method from a non direct base class %r is called',
               'non-parent-init-called',
-              'Used when an __init__ method is called on a class which is not \
-              in the direct ancestors for the analysed class.'),
+              'Used when an __init__ method is called on a class which is not '
+              'in the direct ancestors for the analysed class.'),
     'W0234': ('__iter__ returns non-iterator',
               'non-iterator-returned',
-              'Used when an __iter__ method returns something which is not an \
-               iterable (i.e. has no `%s` method)' % NEXT_METHOD),
+              'Used when an __iter__ method returns something which is not an '
+               'iterable (i.e. has no `%s` method)' % NEXT_METHOD),
     'E0235': ('__exit__ must accept 3 arguments: type, value, traceback',
               'bad-context-manager',
-              'Used when the __exit__ special method, belonging to a \
-               context manager, does not accept 3 arguments \
-               (type, value, traceback).'),
+              'Used when the __exit__ special method, belonging to a '
+              'context manager, does not accept 3 arguments '
+              '(type, value, traceback).'),
     'E0236': ('Invalid object %r in __slots__, must contain '
               'only non empty strings',
               'invalid-slots-object',
diff --git a/pylint/checkers/python3.py b/pylint/checkers/python3.py
index 3ddf495..837cbef 100644
--- a/pylint/checkers/python3.py
+++ b/pylint/checkers/python3.py
@@ -18,6 +18,7 @@ import re
 import tokenize
 
 import astroid
+from astroid import bases
 from pylint import checkers, interfaces
 from pylint.utils import WarningScope
 from pylint.checkers import utils
@@ -217,13 +218,13 @@ class Python3Checker(checkers.BaseChecker):
         'W1618': ('import missing `from __future__ import absolute_import`',
                   'no-absolute-import',
                   'Used when an import is not accompanied by '
-                  '`from __future__ import absolute_import`'
-                  ' (default behaviour in Python 3)',
+                  '``from __future__ import absolute_import`` '
+                  '(default behaviour in Python 3)',
                   {'maxversion': (3, 0)}),
         'W1619': ('division w/o __future__ statement',
                   'old-division',
                   'Used for non-floor division w/o a float literal or '
-                  '``from __future__ import division``'
+                  '``from __future__ import division`` '
                   '(Python 3 returns a float for int division unconditionally)',
                   {'maxversion': (3, 0)}),
         'W1620': ('Calling a dict.iter*() method',
@@ -326,6 +327,13 @@ class Python3Checker(checkers.BaseChecker):
                   'Used when the filter built-in is referenced in a non-iterating '
                   'context (returns an iterator in Python 3)',
                   {'maxversion': (3, 0)}),
+        'W1640': ('Using the cmp argument for list.sort / sorted',
+                  'using-cmp-argument',
+                  'Using the cmp argument for list.sort or the sorted '
+                  'builtin should be avoided, since it was removed in '
+                  'Python 3. Using either `key` or `functools.cmp_to_key` '
+                  'should be preferred.',
+                  {'maxversion': (3, 0)}),
     }
 
     _bad_builtins = frozenset([
@@ -425,7 +433,38 @@ class Python3Checker(checkers.BaseChecker):
             else:
                 self.add_message('old-division', node=node)
 
+    def _check_cmp_argument(self, node):
+        # Check that the `cmp` argument is used
+        args = []
+        if (isinstance(node.func, astroid.Getattr)
+                and node.func.attrname == 'sort'):
+            inferred = utils.safe_infer(node.func.expr)
+            if not inferred:
+                return
+
+            builtins_list = "{}.list".format(bases.BUILTINS)
+            if (isinstance(inferred, astroid.List)
+                    or inferred.qname() == builtins_list):
+                args = node.args
+
+        elif (isinstance(node.func, astroid.Name)
+                and node.func.name == 'sorted'):
+            inferred = utils.safe_infer(node.func)
+            if not inferred:
+                return
+
+            builtins_sorted = "{}.sorted".format(bases.BUILTINS)
+            if inferred.qname() == builtins_sorted:
+                args = node.args
+
+        for arg in args:
+            if isinstance(arg, astroid.Keyword) and arg.arg == 'cmp':
+                self.add_message('using-cmp-argument', node=node)
+                return
+
     def visit_callfunc(self, node):
+        self._check_cmp_argument(node)
+
         if isinstance(node.func, astroid.Getattr):
             if any([node.args, node.starargs, node.kwargs]):
                 return
diff --git a/pylint/lint.py b/pylint/lint.py
index f4c24c6..0c466a1 100644
--- a/pylint/lint.py
+++ b/pylint/lint.py
@@ -456,6 +456,7 @@ class PyLinter(configuration.OptionsManagerMixIn,
         self.register_checker(self)
         self._dynamic_plugins = set()
         self._python3_porting_mode = False
+        self._error_mode = False
         self.load_provider_defaults()
         if reporter:
             self.set_reporter(reporter)
@@ -584,8 +585,16 @@ class PyLinter(configuration.OptionsManagerMixIn,
 
     def error_mode(self):
         """error mode: enable only errors; no reports, no persistent"""
+        self._error_mode = True
         self.disable_noerror_messages()
         self.disable('miscellaneous')
+        if self._python3_porting_mode:
+            self.disable('all')
+            for msg_id in self._checker_messages('python3'):
+                if msg_id.startswith('E'):
+                    self.enable(msg_id)
+        else:
+            self.disable('python3')
         self.set_option('reports', False)
         self.set_option('persistent', False)
 
@@ -593,6 +602,15 @@ class PyLinter(configuration.OptionsManagerMixIn,
         """Disable all other checkers and enable Python 3 warnings."""
         self.disable('all')
         self.enable('python3')
+        if self._error_mode:
+            # The error mode was activated, using the -E flag.
+            # So we'll need to enable only the errors from the
+            # Python 3 porting checker.
+            for msg_id in self._checker_messages('python3'):
+                if msg_id.startswith('E'):
+                    self.enable(msg_id)
+                else:
+                    self.disable(msg_id)
         self._python3_porting_mode = True
 
     # block level option handling #############################################
diff --git a/pylint/test/regrtest_data/py3k_error_flag.py b/pylint/test/regrtest_data/py3k_error_flag.py
new file mode 100644
index 0000000..c12d250
--- /dev/null
+++ b/pylint/test/regrtest_data/py3k_error_flag.py
@@ -0,0 +1,11 @@
+"""Contains both normal error messages and Python3 porting error messages."""

+# pylint: disable=bad-builtin, too-few-public-methods

+

+raise Exception, 1  # Error emitted here with the Python 3 checker.

+

+

+class Test(object):

+    """dummy"""

+

+    def __init__(self):

+        return 42

diff --git a/pylint/test/test_self.py b/pylint/test/test_self.py
index 1734889..9c296b8 100644
--- a/pylint/test/test_self.py
+++ b/pylint/test/test_self.py
@@ -11,10 +11,12 @@
 # this program; if not, write to the Free Software Foundation, Inc.,
 # 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 
+import contextlib
 import sys
 import os
 from os.path import join, dirname, abspath
 import tempfile
+import textwrap
 import unittest
 
 import six
@@ -28,6 +30,17 @@ from pylint.reporters.json import JSONReporter
 HERE = abspath(dirname(__file__))
 
 
+
+@contextlib.contextmanager
+def _patch_streams(out):
+    sys.stderr = sys.stdout = out
+    try:
+        yield
+    finally:
+        sys.stderr = sys.__stderr__
+        sys.stdout = sys.__stdout__
+
+
 class MultiReporter(BaseReporter):
     def __init__(self, reporters):
         self._reporters = reporters
@@ -85,6 +98,15 @@ class RunTC(unittest.TestCase):
             sys.stderr = sys.__stderr__
             sys.stdout = sys.__stdout__
 
+    def _test_output(self, args, expected_output):
+        out = six.StringIO()
+        with _patch_streams(out):
+            with self.assertRaises(SystemExit):
+                Run(args)
+
+            actual_output = out.getvalue()
+            self.assertEqual(expected_output.strip(), actual_output.strip())
+
     def test_pkginfo(self):
         """Make pylint check itself."""
         self._runtest(['pylint.__pkginfo__'], reporter=TextReporter(six.StringIO()),
@@ -151,7 +173,33 @@ class RunTC(unittest.TestCase):
         rc_code = 2 if six.PY2 else 0
         self._runtest([join(HERE, 'functional', 'unpacked_exceptions.py'),
                        '--py3k', '-j 2'],
-                      code=rc_code) 
+                      code=rc_code)
+
+    @unittest.skipIf(sys.version_info[0] > 2, "Requires the --py3k flag.")
+    def test_py3k_commutative_with_errors_only(self):
+
+        # Test what gets emitted with -E only
+        module = join(HERE, 'regrtest_data', 'py3k_error_flag.py')
+        expected = textwrap.dedent("""
+        No config file found, using default configuration
+        ************* Module py3k_error_flag
+        Explicit return in __init__
+        """)
+        self._test_output([module, "-E", "--msg-template='{msg}'"],
+                          expected_output=expected)
+
+        # Test what gets emitted with -E --py3k
+        expected = textwrap.dedent("""
+        No config file found, using default configuration
+        ************* Module py3k_error_flag
+        Use raise ErrorClass(args) instead of raise ErrorClass, args.
+        """)
+        self._test_output([module, "-E", "--py3k", "--msg-template='{msg}'"],
+                          expected_output=expected)
+
+        # Test what gets emitted with --py3k -E
+        self._test_output([module, "--py3k", "-E", "--msg-template='{msg}'"],
+                          expected_output=expected)
 
 
 if __name__ == '__main__':
diff --git a/pylint/test/unittest_checker_python3.py b/pylint/test/unittest_checker_python3.py
index 825e827..bac3f4a 100644
--- a/pylint/test/unittest_checker_python3.py
+++ b/pylint/test/unittest_checker_python3.py
@@ -384,6 +384,19 @@ class Python3CheckerTest(testutils.CheckerTestCase):
         with self.assertNoMessages():
             self.walk(node)
 
+    def test_using_cmp_argument(self):
+        nodes = test_utils.extract_node("""
+        [].sort(cmp=lambda x: x) #@
+        a = list(range(x))
+        a.sort(cmp=lambda x: x) #@
+
+        sorted([], cmp=lambda x: x) #@        
+        """)
+        for node in nodes:
+            message = testutils.Message('using-cmp-argument', node=node)
+            with self.assertAddsMessages(message):
+                self.checker.visit_callfunc(node)
+
 
 @python2_only
 class Python3TokenCheckerTest(testutils.CheckerTestCase):
diff --git a/pylint/testutils.py b/pylint/testutils.py
index 2f9af4d..2ea440d 100644
--- a/pylint/testutils.py
+++ b/pylint/testutils.py
@@ -93,7 +93,7 @@ def get_tests_info(input_dir, msg_dir, prefix, suffix):
 class TestReporter(BaseReporter):
     """reporter storing plain text messages"""
 
-    __implements____ = IReporter
+    __implements__ = IReporter
 
     def __init__(self): # pylint: disable=super-init-not-called
 
diff --git a/pylint/utils.py b/pylint/utils.py
index 6685c4a..6c5b975 100644
--- a/pylint/utils.py
+++ b/pylint/utils.py
@@ -225,6 +225,11 @@ class MessagesHandlerMixIn(object):
         self._msgs_state = {}
         self.msg_status = 0
 
+    def _checker_messages(self, checker):
+        for checker in self._checkers[checker.lower()]:
+            for msgid in checker.msgs:
+                yield msgid
+
     def disable(self, msgid, scope='package', line=None, ignore_unknown=False):
         """don't output message of the given id"""
         assert scope in ('package', 'module')