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988 lines
42 KiB
Python
988 lines
42 KiB
Python
# Copyright (c) 2003-2013 LOGILAB S.A. (Paris, FRANCE).
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# http://www.logilab.fr/ -- mailto:contact@logilab.fr
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# Copyright (c) 2009-2010 Arista Networks, Inc.
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#
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# This program is free software; you can redistribute it and/or modify it under
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# the terms of the GNU General Public License as published by the Free Software
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# Foundation; either version 2 of the License, or (at your option) any later
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# version.
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#
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# This program is distributed in the hope that it will be useful, but WITHOUT
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# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
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# FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
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#
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# You should have received a copy of the GNU General Public License along with
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# this program; if not, write to the Free Software Foundation, Inc.,
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# 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
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"""basic checker for Python code"""
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import sys
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import astroid
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from logilab.common.ureports import Table
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from astroid import are_exclusive
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import astroid.bases
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from pylint.interfaces import IAstroidChecker
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from pylint.utils import EmptyReport
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from pylint.reporters import diff_string
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from pylint.checkers import BaseChecker
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from pylint.checkers.utils import (
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check_messages,
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clobber_in_except,
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is_builtin_object,
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is_inside_except,
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overrides_a_method,
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safe_infer,
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)
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import re
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# regex for class/function/variable/constant name
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CLASS_NAME_RGX = re.compile('[A-Z_][a-zA-Z0-9]+$')
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MOD_NAME_RGX = re.compile('(([a-z_][a-z0-9_]*)|([A-Z][a-zA-Z0-9]+))$')
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CONST_NAME_RGX = re.compile('(([A-Z_][A-Z0-9_]*)|(__.*__))$')
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COMP_VAR_RGX = re.compile('[A-Za-z_][A-Za-z0-9_]*$')
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DEFAULT_NAME_RGX = re.compile('[a-z_][a-z0-9_]{2,30}$')
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CLASS_ATTRIBUTE_RGX = re.compile(r'([A-Za-z_][A-Za-z0-9_]{2,30}|(__.*__))$')
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# do not require a doc string on system methods
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NO_REQUIRED_DOC_RGX = re.compile('__.*__')
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del re
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def in_loop(node):
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"""return True if the node is inside a kind of for loop"""
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parent = node.parent
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while parent is not None:
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if isinstance(parent, (astroid.For, astroid.ListComp, astroid.SetComp,
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astroid.DictComp, astroid.GenExpr)):
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return True
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parent = parent.parent
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return False
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def in_nested_list(nested_list, obj):
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"""return true if the object is an element of <nested_list> or of a nested
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list
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"""
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for elmt in nested_list:
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if isinstance(elmt, (list, tuple)):
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if in_nested_list(elmt, obj):
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return True
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elif elmt == obj:
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return True
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return False
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def _loop_exits_early(loop):
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"""Returns true if a loop has a break statement in its body."""
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loop_nodes = (astroid.For, astroid.While)
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# Loop over body explicitly to avoid matching break statements
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# in orelse.
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for child in loop.body:
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if isinstance(child, loop_nodes):
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continue
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for _ in child.nodes_of_class(astroid.Break, skip_klass=loop_nodes):
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return True
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return False
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def _determine_function_name_type(node):
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"""Determine the name type whose regex the a function's name should match.
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:param node: A function node.
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:returns: One of ('function', 'method', 'attr')
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"""
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if not node.is_method():
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return 'function'
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if node.decorators:
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decorators = node.decorators.nodes
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else:
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decorators = []
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for decorator in decorators:
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# If the function is a property (decorated with @property
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# or @abc.abstractproperty), the name type is 'attr'.
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if (isinstance(decorator, astroid.Name) or
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(isinstance(decorator, astroid.Getattr) and
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decorator.attrname == 'abstractproperty')):
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infered = safe_infer(decorator)
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if (infered and
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infered.qname() in ('__builtin__.property', 'abc.abstractproperty')):
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return 'attr'
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# If the function is decorated using the prop_method.{setter,getter}
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# form, treat it like an attribute as well.
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elif (isinstance(decorator, astroid.Getattr) and
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decorator.attrname in ('setter', 'deleter')):
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return 'attr'
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return 'method'
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def report_by_type_stats(sect, stats, old_stats):
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"""make a report of
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* percentage of different types documented
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* percentage of different types with a bad name
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"""
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# percentage of different types documented and/or with a bad name
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nice_stats = {}
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for node_type in ('module', 'class', 'method', 'function'):
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try:
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total = stats[node_type]
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except KeyError:
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raise EmptyReport()
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nice_stats[node_type] = {}
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if total != 0:
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try:
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documented = total - stats['undocumented_'+node_type]
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percent = (documented * 100.) / total
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nice_stats[node_type]['percent_documented'] = '%.2f' % percent
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except KeyError:
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nice_stats[node_type]['percent_documented'] = 'NC'
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try:
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percent = (stats['badname_'+node_type] * 100.) / total
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nice_stats[node_type]['percent_badname'] = '%.2f' % percent
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except KeyError:
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nice_stats[node_type]['percent_badname'] = 'NC'
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lines = ('type', 'number', 'old number', 'difference',
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'%documented', '%badname')
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for node_type in ('module', 'class', 'method', 'function'):
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new = stats[node_type]
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old = old_stats.get(node_type, None)
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if old is not None:
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diff_str = diff_string(old, new)
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else:
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old, diff_str = 'NC', 'NC'
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lines += (node_type, str(new), str(old), diff_str,
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nice_stats[node_type].get('percent_documented', '0'),
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nice_stats[node_type].get('percent_badname', '0'))
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sect.append(Table(children=lines, cols=6, rheaders=1))
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def redefined_by_decorator(node):
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"""return True if the object is a method redefined via decorator.
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For example:
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@property
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def x(self): return self._x
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@x.setter
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def x(self, value): self._x = value
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"""
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if node.decorators:
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for decorator in node.decorators.nodes:
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if (isinstance(decorator, astroid.Getattr) and
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getattr(decorator.expr, 'name', None) == node.name):
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return True
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return False
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class _BasicChecker(BaseChecker):
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__implements__ = IAstroidChecker
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name = 'basic'
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class BasicErrorChecker(_BasicChecker):
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msgs = {
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'E0100': ('__init__ method is a generator',
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'init-is-generator',
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'Used when the special class method __init__ is turned into a '
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'generator by a yield in its body.'),
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'E0101': ('Explicit return in __init__',
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'return-in-init',
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'Used when the special class method __init__ has an explicit \
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return value.'),
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'E0102': ('%s already defined line %s',
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'function-redefined',
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'Used when a function / class / method is redefined.'),
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'E0103': ('%r not properly in loop',
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'not-in-loop',
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'Used when break or continue keywords are used outside a loop.'),
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'E0104': ('Return outside function',
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'return-outside-function',
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'Used when a "return" statement is found outside a function or '
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'method.'),
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'E0105': ('Yield outside function',
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'yield-outside-function',
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'Used when a "yield" statement is found outside a function or '
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'method.'),
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'E0106': ('Return with argument inside generator',
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'return-arg-in-generator',
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'Used when a "return" statement with an argument is found '
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'outside in a generator function or method (e.g. with some '
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'"yield" statements).'),
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'E0107': ("Use of the non-existent %s operator",
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'nonexistent-operator',
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"Used when you attempt to use the C-style pre-increment or"
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"pre-decrement operator -- and ++, which doesn't exist in Python."),
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'E0108': ('Duplicate argument name %s in function definition',
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'duplicate-argument-name',
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'Duplicate argument names in function definitions are syntax'
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' errors.'),
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'W0120': ('Else clause on loop without a break statement',
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'useless-else-on-loop',
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'Loops should only have an else clause if they can exit early '
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'with a break statement, otherwise the statements under else '
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'should be on the same scope as the loop itself.'),
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}
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def __init__(self, linter):
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_BasicChecker.__init__(self, linter)
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@check_messages('function-redefined')
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def visit_class(self, node):
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self._check_redefinition('class', node)
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@check_messages('init-is-generator', 'return-in-init',
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'function-redefined', 'return-arg-in-generator',
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'duplicate-argument-name')
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def visit_function(self, node):
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if not redefined_by_decorator(node):
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self._check_redefinition(node.is_method() and 'method' or 'function', node)
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# checks for max returns, branch, return in __init__
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returns = node.nodes_of_class(astroid.Return,
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skip_klass=(astroid.Function, astroid.Class))
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if node.is_method() and node.name == '__init__':
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if node.is_generator():
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self.add_message('init-is-generator', node=node)
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else:
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values = [r.value for r in returns]
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# Are we returning anything but None from constructors
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if [v for v in values if
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not (v is None or
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(isinstance(v, astroid.Const) and v.value is None) or
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(isinstance(v, astroid.Name) and v.name == 'None')
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) ]:
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self.add_message('return-in-init', node=node)
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elif node.is_generator():
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# make sure we don't mix non-None returns and yields
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for retnode in returns:
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if isinstance(retnode.value, astroid.Const) and \
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retnode.value.value is not None:
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self.add_message('return-arg-in-generator', node=node,
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line=retnode.fromlineno)
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# Check for duplicate names
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args = set()
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for name in node.argnames():
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if name in args:
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self.add_message('duplicate-argument-name', node=node, args=(name,))
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else:
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args.add(name)
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@check_messages('return-outside-function')
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def visit_return(self, node):
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if not isinstance(node.frame(), astroid.Function):
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self.add_message('return-outside-function', node=node)
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@check_messages('yield-outside-function')
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def visit_yield(self, node):
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if not isinstance(node.frame(), (astroid.Function, astroid.Lambda)):
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self.add_message('yield-outside-function', node=node)
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@check_messages('not-in-loop')
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def visit_continue(self, node):
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self._check_in_loop(node, 'continue')
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@check_messages('not-in-loop')
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def visit_break(self, node):
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self._check_in_loop(node, 'break')
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@check_messages('useless-else-on-loop')
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def visit_for(self, node):
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self._check_else_on_loop(node)
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@check_messages('useless-else-on-loop')
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def visit_while(self, node):
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self._check_else_on_loop(node)
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@check_messages('nonexistent-operator')
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def visit_unaryop(self, node):
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"""check use of the non-existent ++ and -- operator operator"""
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if ((node.op in '+-') and
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isinstance(node.operand, astroid.UnaryOp) and
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(node.operand.op == node.op)):
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self.add_message('nonexistent-operator', node=node, args=node.op*2)
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def _check_else_on_loop(self, node):
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"""Check that any loop with an else clause has a break statement."""
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if node.orelse and not _loop_exits_early(node):
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self.add_message('useless-else-on-loop', node=node,
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# This is not optimal, but the line previous
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# to the first statement in the else clause
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# will usually be the one that contains the else:.
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line=node.orelse[0].lineno - 1)
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def _check_in_loop(self, node, node_name):
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"""check that a node is inside a for or while loop"""
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_node = node.parent
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while _node:
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if isinstance(_node, (astroid.For, astroid.While)):
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break
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_node = _node.parent
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else:
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self.add_message('not-in-loop', node=node, args=node_name)
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def _check_redefinition(self, redeftype, node):
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"""check for redefinition of a function / method / class name"""
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defined_self = node.parent.frame()[node.name]
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if defined_self is not node and not are_exclusive(node, defined_self):
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self.add_message('function-redefined', node=node,
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args=(redeftype, defined_self.fromlineno))
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class BasicChecker(_BasicChecker):
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"""checks for :
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* doc strings
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* number of arguments, local variables, branches, returns and statements in
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functions, methods
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* required module attributes
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* dangerous default values as arguments
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* redefinition of function / method / class
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* uses of the global statement
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"""
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__implements__ = IAstroidChecker
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name = 'basic'
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msgs = {
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'W0101': ('Unreachable code',
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'unreachable',
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'Used when there is some code behind a "return" or "raise" \
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statement, which will never be accessed.'),
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'W0102': ('Dangerous default value %s as argument',
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'dangerous-default-value',
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'Used when a mutable value as list or dictionary is detected in \
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a default value for an argument.'),
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'W0104': ('Statement seems to have no effect',
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'pointless-statement',
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'Used when a statement doesn\'t have (or at least seems to) \
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any effect.'),
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'W0105': ('String statement has no effect',
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'pointless-string-statement',
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'Used when a string is used as a statement (which of course \
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has no effect). This is a particular case of W0104 with its \
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own message so you can easily disable it if you\'re using \
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those strings as documentation, instead of comments.'),
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'W0106': ('Expression "%s" is assigned to nothing',
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'expression-not-assigned',
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'Used when an expression that is not a function call is assigned\
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to nothing. Probably something else was intended.'),
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'W0108': ('Lambda may not be necessary',
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'unnecessary-lambda',
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'Used when the body of a lambda expression is a function call \
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on the same argument list as the lambda itself; such lambda \
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expressions are in all but a few cases replaceable with the \
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function being called in the body of the lambda.'),
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'W0109': ("Duplicate key %r in dictionary",
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'duplicate-key',
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"Used when a dictionary expression binds the same key multiple \
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times."),
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'W0122': ('Use of the exec statement',
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'exec-statement',
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'Used when you use the "exec" statement, to discourage its \
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usage. That doesn\'t mean you can not use it !',
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{'maxversion': (3, 0)}),
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'W0141': ('Used builtin function %r',
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'bad-builtin',
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'Used when a black listed builtin function is used (see the '
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'bad-function option). Usual black listed functions are the ones '
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'like map, or filter , where Python offers now some cleaner '
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'alternative like list comprehension.'),
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'W0142': ('Used * or ** magic',
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'star-args',
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'Used when a function or method is called using `*args` or '
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'`**kwargs` to dispatch arguments. This doesn\'t improve '
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'readability and should be used with care.'),
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'W0150': ("%s statement in finally block may swallow exception",
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'lost-exception',
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"Used when a break or a return statement is found inside the \
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finally clause of a try...finally block: the exceptions raised \
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in the try clause will be silently swallowed instead of being \
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re-raised."),
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'W0199': ('Assert called on a 2-uple. Did you mean \'assert x,y\'?',
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'assert-on-tuple',
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'A call of assert on a tuple will always evaluate to true if '
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'the tuple is not empty, and will always evaluate to false if '
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'it is.'),
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'W0121': ('Use raise ErrorClass(args) instead of raise ErrorClass, args.',
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'old-raise-syntax',
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"Used when the alternate raise syntax 'raise foo, bar' is used "
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"instead of 'raise foo(bar)'.",
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{'maxversion': (3, 0)}),
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'C0121': ('Missing required attribute "%s"', # W0103
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'missing-module-attribute',
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'Used when an attribute required for modules is missing.'),
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}
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options = (('required-attributes',
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{'default' : (), 'type' : 'csv',
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'metavar' : '<attributes>',
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'help' : 'Required attributes for module, separated by a '
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'comma'}
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),
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('bad-functions',
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{'default' : ('map', 'filter', 'apply', 'input'),
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'type' :'csv', 'metavar' : '<builtin function names>',
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'help' : 'List of builtins function names that should not be '
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'used, separated by a comma'}
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),
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)
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reports = ( ('RP0101', 'Statistics by type', report_by_type_stats), )
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def __init__(self, linter):
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_BasicChecker.__init__(self, linter)
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self.stats = None
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self._tryfinallys = None
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def open(self):
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"""initialize visit variables and statistics
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"""
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self._tryfinallys = []
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self.stats = self.linter.add_stats(module=0, function=0,
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method=0, class_=0)
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@check_messages('missing-module-attribute')
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def visit_module(self, node):
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"""check module name, docstring and required arguments
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"""
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self.stats['module'] += 1
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for attr in self.config.required_attributes:
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if attr not in node:
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self.add_message('missing-module-attribute', node=node, args=attr)
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def visit_class(self, node):
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"""check module name, docstring and redefinition
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increment branch counter
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"""
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self.stats['class'] += 1
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@check_messages('pointless-statement', 'pointless-string-statement',
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'expression-not-assigned')
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def visit_discard(self, node):
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"""check for various kind of statements without effect"""
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expr = node.value
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if isinstance(expr, astroid.Const) and isinstance(expr.value,
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basestring):
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# treat string statement in a separated message
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self.add_message('pointless-string-statement', node=node)
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return
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# ignore if this is :
|
|
# * a direct function call
|
|
# * the unique child of a try/except body
|
|
# * a yield (which are wrapped by a discard node in _ast XXX)
|
|
# warn W0106 if we have any underlying function call (we can't predict
|
|
# side effects), else pointless-statement
|
|
if (isinstance(expr, (astroid.Yield, astroid.CallFunc)) or
|
|
(isinstance(node.parent, astroid.TryExcept) and
|
|
node.parent.body == [node])):
|
|
return
|
|
if any(expr.nodes_of_class(astroid.CallFunc)):
|
|
self.add_message('expression-not-assigned', node=node, args=expr.as_string())
|
|
else:
|
|
self.add_message('pointless-statement', node=node)
|
|
|
|
@check_messages('unnecessary-lambda')
|
|
def visit_lambda(self, node):
|
|
"""check whether or not the lambda is suspicious
|
|
"""
|
|
# if the body of the lambda is a call expression with the same
|
|
# argument list as the lambda itself, then the lambda is
|
|
# possibly unnecessary and at least suspicious.
|
|
if node.args.defaults:
|
|
# If the arguments of the lambda include defaults, then a
|
|
# judgment cannot be made because there is no way to check
|
|
# that the defaults defined by the lambda are the same as
|
|
# the defaults defined by the function called in the body
|
|
# of the lambda.
|
|
return
|
|
call = node.body
|
|
if not isinstance(call, astroid.CallFunc):
|
|
# The body of the lambda must be a function call expression
|
|
# for the lambda to be unnecessary.
|
|
return
|
|
# XXX are lambda still different with astroid >= 0.18 ?
|
|
# *args and **kwargs need to be treated specially, since they
|
|
# are structured differently between the lambda and the function
|
|
# call (in the lambda they appear in the args.args list and are
|
|
# indicated as * and ** by two bits in the lambda's flags, but
|
|
# in the function call they are omitted from the args list and
|
|
# are indicated by separate attributes on the function call node).
|
|
ordinary_args = list(node.args.args)
|
|
if node.args.kwarg:
|
|
if (not call.kwargs
|
|
or not isinstance(call.kwargs, astroid.Name)
|
|
or node.args.kwarg != call.kwargs.name):
|
|
return
|
|
elif call.kwargs:
|
|
return
|
|
if node.args.vararg:
|
|
if (not call.starargs
|
|
or not isinstance(call.starargs, astroid.Name)
|
|
or node.args.vararg != call.starargs.name):
|
|
return
|
|
elif call.starargs:
|
|
return
|
|
# The "ordinary" arguments must be in a correspondence such that:
|
|
# ordinary_args[i].name == call.args[i].name.
|
|
if len(ordinary_args) != len(call.args):
|
|
return
|
|
for i in xrange(len(ordinary_args)):
|
|
if not isinstance(call.args[i], astroid.Name):
|
|
return
|
|
if node.args.args[i].name != call.args[i].name:
|
|
return
|
|
self.add_message('unnecessary-lambda', line=node.fromlineno, node=node)
|
|
|
|
@check_messages('dangerous-default-value')
|
|
def visit_function(self, node):
|
|
"""check function name, docstring, arguments, redefinition,
|
|
variable names, max locals
|
|
"""
|
|
self.stats[node.is_method() and 'method' or 'function'] += 1
|
|
# check for dangerous default values as arguments
|
|
for default in node.args.defaults:
|
|
try:
|
|
value = default.infer().next()
|
|
except astroid.InferenceError:
|
|
continue
|
|
builtins = astroid.bases.BUILTINS
|
|
if (isinstance(value, astroid.Instance) and
|
|
value.qname() in ['.'.join([builtins, x]) for x in ('set', 'dict', 'list')]):
|
|
if value is default:
|
|
msg = default.as_string()
|
|
elif type(value) is astroid.Instance:
|
|
msg = '%s (%s)' % (default.as_string(), value.qname())
|
|
else:
|
|
msg = '%s (%s)' % (default.as_string(), value.as_string())
|
|
self.add_message('dangerous-default-value', node=node, args=(msg,))
|
|
|
|
@check_messages('unreachable', 'lost-exception')
|
|
def visit_return(self, node):
|
|
"""1 - check is the node has a right sibling (if so, that's some
|
|
unreachable code)
|
|
2 - check is the node is inside the finally clause of a try...finally
|
|
block
|
|
"""
|
|
self._check_unreachable(node)
|
|
# Is it inside final body of a try...finally bloc ?
|
|
self._check_not_in_finally(node, 'return', (astroid.Function,))
|
|
|
|
@check_messages('unreachable')
|
|
def visit_continue(self, node):
|
|
"""check is the node has a right sibling (if so, that's some unreachable
|
|
code)
|
|
"""
|
|
self._check_unreachable(node)
|
|
|
|
@check_messages('unreachable', 'lost-exception')
|
|
def visit_break(self, node):
|
|
"""1 - check is the node has a right sibling (if so, that's some
|
|
unreachable code)
|
|
2 - check is the node is inside the finally clause of a try...finally
|
|
block
|
|
"""
|
|
# 1 - Is it right sibling ?
|
|
self._check_unreachable(node)
|
|
# 2 - Is it inside final body of a try...finally bloc ?
|
|
self._check_not_in_finally(node, 'break', (astroid.For, astroid.While,))
|
|
|
|
@check_messages('unreachable', 'old-raise-syntax')
|
|
def visit_raise(self, node):
|
|
"""check if the node has a right sibling (if so, that's some unreachable
|
|
code)
|
|
"""
|
|
self._check_unreachable(node)
|
|
if sys.version_info >= (3, 0):
|
|
return
|
|
if node.exc is not None and node.inst is not None and node.tback is None:
|
|
self.add_message('old-raise-syntax', node=node)
|
|
|
|
@check_messages('exec-statement')
|
|
def visit_exec(self, node):
|
|
"""just print a warning on exec statements"""
|
|
self.add_message('exec-statement', node=node)
|
|
|
|
@check_messages('bad-builtin', 'star-args')
|
|
def visit_callfunc(self, node):
|
|
"""visit a CallFunc node -> check if this is not a blacklisted builtin
|
|
call and check for * or ** use
|
|
"""
|
|
if isinstance(node.func, astroid.Name):
|
|
name = node.func.name
|
|
# ignore the name if it's not a builtin (i.e. not defined in the
|
|
# locals nor globals scope)
|
|
if not (name in node.frame() or
|
|
name in node.root()):
|
|
if name in self.config.bad_functions:
|
|
self.add_message('bad-builtin', node=node, args=name)
|
|
if node.starargs or node.kwargs:
|
|
scope = node.scope()
|
|
if isinstance(scope, astroid.Function):
|
|
toprocess = [(n, vn) for (n, vn) in ((node.starargs, scope.args.vararg),
|
|
(node.kwargs, scope.args.kwarg)) if n]
|
|
if toprocess:
|
|
for cfnode, fargname in toprocess[:]:
|
|
if getattr(cfnode, 'name', None) == fargname:
|
|
toprocess.remove((cfnode, fargname))
|
|
if not toprocess:
|
|
return # star-args can be skipped
|
|
self.add_message('star-args', node=node.func)
|
|
|
|
@check_messages('assert-on-tuple')
|
|
def visit_assert(self, node):
|
|
"""check the use of an assert statement on a tuple."""
|
|
if node.fail is None and isinstance(node.test, astroid.Tuple) and \
|
|
len(node.test.elts) == 2:
|
|
self.add_message('assert-on-tuple', node=node)
|
|
|
|
@check_messages('duplicate-key')
|
|
def visit_dict(self, node):
|
|
"""check duplicate key in dictionary"""
|
|
keys = set()
|
|
for k, _ in node.items:
|
|
if isinstance(k, astroid.Const):
|
|
key = k.value
|
|
if key in keys:
|
|
self.add_message('duplicate-key', node=node, args=key)
|
|
keys.add(key)
|
|
|
|
def visit_tryfinally(self, node):
|
|
"""update try...finally flag"""
|
|
self._tryfinallys.append(node)
|
|
|
|
def leave_tryfinally(self, node):
|
|
"""update try...finally flag"""
|
|
self._tryfinallys.pop()
|
|
|
|
def _check_unreachable(self, node):
|
|
"""check unreachable code"""
|
|
unreach_stmt = node.next_sibling()
|
|
if unreach_stmt is not None:
|
|
self.add_message('unreachable', node=unreach_stmt)
|
|
|
|
def _check_not_in_finally(self, node, node_name, breaker_classes=()):
|
|
"""check that a node is not inside a finally clause of a
|
|
try...finally statement.
|
|
If we found before a try...finally bloc a parent which its type is
|
|
in breaker_classes, we skip the whole check."""
|
|
# if self._tryfinallys is empty, we're not a in try...finally bloc
|
|
if not self._tryfinallys:
|
|
return
|
|
# the node could be a grand-grand...-children of the try...finally
|
|
_parent = node.parent
|
|
_node = node
|
|
while _parent and not isinstance(_parent, breaker_classes):
|
|
if hasattr(_parent, 'finalbody') and _node in _parent.finalbody:
|
|
self.add_message('lost-exception', node=node, args=node_name)
|
|
return
|
|
_node = _parent
|
|
_parent = _node.parent
|
|
|
|
|
|
class NameChecker(_BasicChecker):
|
|
msgs = {
|
|
'C0102': ('Black listed name "%s"',
|
|
'blacklisted-name',
|
|
'Used when the name is listed in the black list (unauthorized \
|
|
names).'),
|
|
'C0103': ('Invalid %s name "%s"',
|
|
'invalid-name',
|
|
'Used when the name doesn\'t match the regular expression \
|
|
associated to its type (constant, variable, class...).'),
|
|
}
|
|
|
|
options = (('module-rgx',
|
|
{'default' : MOD_NAME_RGX,
|
|
'type' :'regexp', 'metavar' : '<regexp>',
|
|
'help' : 'Regular expression which should only match correct '
|
|
'module names'}
|
|
),
|
|
('const-rgx',
|
|
{'default' : CONST_NAME_RGX,
|
|
'type' :'regexp', 'metavar' : '<regexp>',
|
|
'help' : 'Regular expression which should only match correct '
|
|
'module level names'}
|
|
),
|
|
('class-rgx',
|
|
{'default' : CLASS_NAME_RGX,
|
|
'type' :'regexp', 'metavar' : '<regexp>',
|
|
'help' : 'Regular expression which should only match correct '
|
|
'class names'}
|
|
),
|
|
('function-rgx',
|
|
{'default' : DEFAULT_NAME_RGX,
|
|
'type' :'regexp', 'metavar' : '<regexp>',
|
|
'help' : 'Regular expression which should only match correct '
|
|
'function names'}
|
|
),
|
|
('method-rgx',
|
|
{'default' : DEFAULT_NAME_RGX,
|
|
'type' :'regexp', 'metavar' : '<regexp>',
|
|
'help' : 'Regular expression which should only match correct '
|
|
'method names'}
|
|
),
|
|
('attr-rgx',
|
|
{'default' : DEFAULT_NAME_RGX,
|
|
'type' :'regexp', 'metavar' : '<regexp>',
|
|
'help' : 'Regular expression which should only match correct '
|
|
'instance attribute names'}
|
|
),
|
|
('argument-rgx',
|
|
{'default' : DEFAULT_NAME_RGX,
|
|
'type' :'regexp', 'metavar' : '<regexp>',
|
|
'help' : 'Regular expression which should only match correct '
|
|
'argument names'}),
|
|
('variable-rgx',
|
|
{'default' : DEFAULT_NAME_RGX,
|
|
'type' :'regexp', 'metavar' : '<regexp>',
|
|
'help' : 'Regular expression which should only match correct '
|
|
'variable names'}
|
|
),
|
|
('class-attribute-rgx',
|
|
{'default' : CLASS_ATTRIBUTE_RGX,
|
|
'type' :'regexp', 'metavar' : '<regexp>',
|
|
'help' : 'Regular expression which should only match correct '
|
|
'attribute names in class bodies'}
|
|
),
|
|
('inlinevar-rgx',
|
|
{'default' : COMP_VAR_RGX,
|
|
'type' :'regexp', 'metavar' : '<regexp>',
|
|
'help' : 'Regular expression which should only match correct '
|
|
'list comprehension / generator expression variable \
|
|
names'}
|
|
),
|
|
# XXX use set
|
|
('good-names',
|
|
{'default' : ('i', 'j', 'k', 'ex', 'Run', '_'),
|
|
'type' :'csv', 'metavar' : '<names>',
|
|
'help' : 'Good variable names which should always be accepted,'
|
|
' separated by a comma'}
|
|
),
|
|
('bad-names',
|
|
{'default' : ('foo', 'bar', 'baz', 'toto', 'tutu', 'tata'),
|
|
'type' :'csv', 'metavar' : '<names>',
|
|
'help' : 'Bad variable names which should always be refused, '
|
|
'separated by a comma'}
|
|
),
|
|
)
|
|
|
|
def open(self):
|
|
self.stats = self.linter.add_stats(badname_module=0,
|
|
badname_class=0, badname_function=0,
|
|
badname_method=0, badname_attr=0,
|
|
badname_const=0,
|
|
badname_variable=0,
|
|
badname_inlinevar=0,
|
|
badname_argument=0,
|
|
badname_class_attribute=0)
|
|
|
|
@check_messages('blacklisted-name', 'invalid-name')
|
|
def visit_module(self, node):
|
|
self._check_name('module', node.name.split('.')[-1], node)
|
|
|
|
@check_messages('blacklisted-name', 'invalid-name')
|
|
def visit_class(self, node):
|
|
self._check_name('class', node.name, node)
|
|
for attr, anodes in node.instance_attrs.iteritems():
|
|
if not list(node.instance_attr_ancestors(attr)):
|
|
self._check_name('attr', attr, anodes[0])
|
|
|
|
@check_messages('blacklisted-name', 'invalid-name')
|
|
def visit_function(self, node):
|
|
# Do not emit any warnings if the method is just an implementation
|
|
# of a base class method.
|
|
if node.is_method() and overrides_a_method(node.parent.frame(), node.name):
|
|
return
|
|
self._check_name(_determine_function_name_type(node),
|
|
node.name, node)
|
|
# Check argument names
|
|
args = node.args.args
|
|
if args is not None:
|
|
self._recursive_check_names(args, node)
|
|
|
|
@check_messages('blacklisted-name', 'invalid-name')
|
|
def visit_global(self, node):
|
|
for name in node.names:
|
|
self._check_name('const', name, node)
|
|
|
|
@check_messages('blacklisted-name', 'invalid-name')
|
|
def visit_assname(self, node):
|
|
"""check module level assigned names"""
|
|
frame = node.frame()
|
|
ass_type = node.ass_type()
|
|
if isinstance(ass_type, astroid.Comprehension):
|
|
self._check_name('inlinevar', node.name, node)
|
|
elif isinstance(frame, astroid.Module):
|
|
if isinstance(ass_type, astroid.Assign) and not in_loop(ass_type):
|
|
if isinstance(safe_infer(ass_type.value), astroid.Class):
|
|
self._check_name('class', node.name, node)
|
|
else:
|
|
self._check_name('const', node.name, node)
|
|
elif isinstance(ass_type, astroid.ExceptHandler):
|
|
self._check_name('variable', node.name, node)
|
|
elif isinstance(frame, astroid.Function):
|
|
# global introduced variable aren't in the function locals
|
|
if node.name in frame and node.name not in frame.argnames():
|
|
self._check_name('variable', node.name, node)
|
|
elif isinstance(frame, astroid.Class):
|
|
if not list(frame.local_attr_ancestors(node.name)):
|
|
self._check_name('class_attribute', node.name, node)
|
|
|
|
def _recursive_check_names(self, args, node):
|
|
"""check names in a possibly recursive list <arg>"""
|
|
for arg in args:
|
|
if isinstance(arg, astroid.AssName):
|
|
self._check_name('argument', arg.name, node)
|
|
else:
|
|
self._recursive_check_names(arg.elts, node)
|
|
|
|
def _check_name(self, node_type, name, node):
|
|
"""check for a name using the type's regexp"""
|
|
if is_inside_except(node):
|
|
clobbering, _ = clobber_in_except(node)
|
|
if clobbering:
|
|
return
|
|
if name in self.config.good_names:
|
|
return
|
|
if name in self.config.bad_names:
|
|
self.stats['badname_' + node_type] += 1
|
|
self.add_message('blacklisted-name', node=node, args=name)
|
|
return
|
|
regexp = getattr(self.config, node_type + '_rgx')
|
|
if regexp.match(name) is None:
|
|
type_label = {'inlinedvar': 'inlined variable',
|
|
'const': 'constant',
|
|
'attr': 'attribute',
|
|
'class_attribute': 'class attribute'
|
|
}.get(node_type, node_type)
|
|
self.add_message('invalid-name', node=node, args=(type_label, name))
|
|
self.stats['badname_' + node_type] += 1
|
|
|
|
|
|
class DocStringChecker(_BasicChecker):
|
|
msgs = {
|
|
'C0111': ('Missing %s docstring', # W0131
|
|
'missing-docstring',
|
|
'Used when a module, function, class or method has no docstring.\
|
|
Some special methods like __init__ doesn\'t necessary require a \
|
|
docstring.'),
|
|
'C0112': ('Empty %s docstring', # W0132
|
|
'empty-docstring',
|
|
'Used when a module, function, class or method has an empty \
|
|
docstring (it would be too easy ;).'),
|
|
}
|
|
options = (('no-docstring-rgx',
|
|
{'default' : NO_REQUIRED_DOC_RGX,
|
|
'type' : 'regexp', 'metavar' : '<regexp>',
|
|
'help' : 'Regular expression which should only match '
|
|
'function or class names that do not require a '
|
|
'docstring.'}
|
|
),
|
|
('docstring-min-length',
|
|
{'default' : -1,
|
|
'type' : 'int', 'metavar' : '<int>',
|
|
'help': ('Minimum line length for functions/classes that'
|
|
' require docstrings, shorter ones are exempt.')}
|
|
),
|
|
)
|
|
|
|
|
|
def open(self):
|
|
self.stats = self.linter.add_stats(undocumented_module=0,
|
|
undocumented_function=0,
|
|
undocumented_method=0,
|
|
undocumented_class=0)
|
|
@check_messages('missing-docstring', 'empty-docstring')
|
|
def visit_module(self, node):
|
|
self._check_docstring('module', node)
|
|
|
|
@check_messages('missing-docstring', 'empty-docstring')
|
|
def visit_class(self, node):
|
|
if self.config.no_docstring_rgx.match(node.name) is None:
|
|
self._check_docstring('class', node)
|
|
@check_messages('missing-docstring', 'empty-docstring')
|
|
def visit_function(self, node):
|
|
if self.config.no_docstring_rgx.match(node.name) is None:
|
|
ftype = node.is_method() and 'method' or 'function'
|
|
if isinstance(node.parent.frame(), astroid.Class):
|
|
overridden = False
|
|
# check if node is from a method overridden by its ancestor
|
|
for ancestor in node.parent.frame().ancestors():
|
|
if node.name in ancestor and \
|
|
isinstance(ancestor[node.name], astroid.Function):
|
|
overridden = True
|
|
break
|
|
if not overridden:
|
|
self._check_docstring(ftype, node)
|
|
else:
|
|
self._check_docstring(ftype, node)
|
|
|
|
def _check_docstring(self, node_type, node):
|
|
"""check the node has a non empty docstring"""
|
|
docstring = node.doc
|
|
if docstring is None:
|
|
if node.body:
|
|
lines = node.body[-1].lineno - node.body[0].lineno + 1
|
|
else:
|
|
lines = 0
|
|
max_lines = self.config.docstring_min_length
|
|
|
|
if node_type != 'module' and max_lines > -1 and lines < max_lines:
|
|
return
|
|
self.stats['undocumented_'+node_type] += 1
|
|
self.add_message('missing-docstring', node=node, args=(node_type,))
|
|
elif not docstring.strip():
|
|
self.stats['undocumented_'+node_type] += 1
|
|
self.add_message('empty-docstring', node=node, args=(node_type,))
|
|
|
|
|
|
class PassChecker(_BasicChecker):
|
|
"""check if the pass statement is really necessary"""
|
|
msgs = {'W0107': ('Unnecessary pass statement',
|
|
'unnecessary-pass',
|
|
'Used when a "pass" statement that can be avoided is '
|
|
'encountered.'),
|
|
}
|
|
@check_messages('unnecessary-pass')
|
|
def visit_pass(self, node):
|
|
if len(node.parent.child_sequence(node)) > 1:
|
|
self.add_message('unnecessary-pass', node=node)
|
|
|
|
|
|
class LambdaForComprehensionChecker(_BasicChecker):
|
|
"""check for using a lambda where a comprehension would do.
|
|
|
|
See <http://www.artima.com/weblogs/viewpost.jsp?thread=98196>
|
|
where GvR says comprehensions would be clearer.
|
|
"""
|
|
|
|
msgs = {'W0110': ('map/filter on lambda could be replaced by comprehension',
|
|
'deprecated-lambda',
|
|
'Used when a lambda is the first argument to "map" or '
|
|
'"filter". It could be clearer as a list '
|
|
'comprehension or generator expression.',
|
|
{'maxversion': (3, 0)}),
|
|
}
|
|
|
|
@check_messages('deprecated-lambda')
|
|
def visit_callfunc(self, node):
|
|
"""visit a CallFunc node, check if map or filter are called with a
|
|
lambda
|
|
"""
|
|
if not node.args:
|
|
return
|
|
if not isinstance(node.args[0], astroid.Lambda):
|
|
return
|
|
infered = safe_infer(node.func)
|
|
if (is_builtin_object(infered)
|
|
and infered.name in ['map', 'filter']):
|
|
self.add_message('deprecated-lambda', node=node)
|
|
|
|
|
|
def register(linter):
|
|
"""required method to auto register this checker"""
|
|
linter.register_checker(BasicErrorChecker(linter))
|
|
linter.register_checker(BasicChecker(linter))
|
|
linter.register_checker(NameChecker(linter))
|
|
linter.register_checker(DocStringChecker(linter))
|
|
linter.register_checker(PassChecker(linter))
|
|
linter.register_checker(LambdaForComprehensionChecker(linter))
|