#!/usr/bin/python # -*- coding: utf-8 -*- # # Copyright (C) 2009 Google Inc. All rights reserved. # Copyright (C) 2009 Torch Mobile Inc. # # Redistribution and use in source and binary forms, with or without # modification, are permitted provided that the following conditions are # met: # # * Redistributions of source code must retain the above copyright # notice, this list of conditions and the following disclaimer. # * Redistributions in binary form must reproduce the above # copyright notice, this list of conditions and the following disclaimer # in the documentation and/or other materials provided with the # distribution. # * Neither the name of Google Inc. nor the names of its # contributors may be used to endorse or promote products derived from # this software without specific prior written permission. # # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS # "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT # LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR # A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT # OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, # SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT # LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, # DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY # THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. # This is the modified version of Google's cpplint. The original code is # http://google-styleguide.googlecode.com/svn/trunk/cpplint/cpplint.py """Does WebKit-lint on c++ files. The goal of this script is to identify places in the code that *may* be in non-compliance with WebKit style. It does not attempt to fix up these problems -- the point is to educate. It does also not attempt to find all problems, or to ensure that everything it does find is legitimately a problem. In particular, we can get very confused by /* and // inside strings! We do a small hack, which is to ignore //'s with "'s after them on the same line, but it is far from perfect (in either direction). """ import codecs import getopt import math # for log import os import os.path import re import sre_compile import string import sys import unicodedata _USAGE = """ Syntax: cpplint.py [--verbose=#] [--output=vs7] [--filter=-x,+y,...] [file] ... The style guidelines this tries to follow are those in http://webkit.org/coding/coding-style.html Every problem is given a confidence score from 1-5, with 5 meaning we are certain of the problem, and 1 meaning it could be a legitimate construct. This will miss some errors, and is not a substitute for a code review. To prevent specific lines from being linted, add a '// NOLINT' comment to the end of the line. The files passed in will be linted; at least one file must be provided. Linted extensions are .cpp, .c and .h. Other file types will be ignored. Flags: output=vs7 By default, the output is formatted to ease emacs parsing. Visual Studio compatible output (vs7) may also be used. Other formats are unsupported. verbose=# Specify a number 0-5 to restrict errors to certain verbosity levels. filter=-x,+y,... Specify a comma-separated list of category-filters to apply: only error messages whose category names pass the filters will be printed. (Category names are printed with the message and look like "[whitespace/indent]".) Filters are evaluated left to right. "-FOO" and "FOO" means "do not print categories that start with FOO". "+FOO" means "do print categories that start with FOO". Examples: --filter=-whitespace,+whitespace/braces --filter=whitespace,runtime/printf,+runtime/printf_format --filter=-,+build/include_what_you_use To see a list of all the categories used in cpplint, pass no arg: --filter= """ # We categorize each error message we print. Here are the categories. # We want an explicit list so we can list them all in cpplint --filter=. # If you add a new error message with a new category, add it to the list # here! cpplint_unittest.py should tell you if you forget to do this. # \ used for clearer layout -- pylint: disable-msg=C6013 _ERROR_CATEGORIES = '''\ build/class build/deprecated build/endif_comment build/forward_decl build/header_guard build/include build/include_order build/include_what_you_use build/namespaces build/printf_format build/storage_class legal/copyright readability/braces readability/casting readability/check readability/comparison_to_zero readability/constructors readability/control_flow readability/fn_size readability/function readability/multiline_comment readability/multiline_string readability/null readability/streams readability/todo readability/utf8 runtime/arrays runtime/casting runtime/explicit runtime/int runtime/init runtime/invalid_increment runtime/memset runtime/printf runtime/printf_format runtime/references runtime/rtti runtime/sizeof runtime/string runtime/threadsafe_fn runtime/virtual whitespace/blank_line whitespace/braces whitespace/comma whitespace/comments whitespace/comments-doublespace whitespace/end_of_line whitespace/ending_newline whitespace/indent whitespace/labels whitespace/line_length whitespace/newline whitespace/operators whitespace/parens whitespace/semicolon whitespace/tab whitespace/todo ''' # The default state of the category filter. This is overrided by the --filter= # flag. By default all errors are on, so only add here categories that should be # off by default (i.e., categories that must be enabled by the --filter= flags). # All entries here should start with a '-' or '+', as in the --filter= flag. _DEFAULT_FILTERS = [] # Headers that we consider STL headers. _STL_HEADERS = frozenset([ 'algobase.h', 'algorithm', 'alloc.h', 'bitset', 'deque', 'exception', 'function.h', 'functional', 'hash_map', 'hash_map.h', 'hash_set', 'hash_set.h', 'iterator', 'list', 'list.h', 'map', 'memory', 'pair.h', 'pthread_alloc', 'queue', 'set', 'set.h', 'sstream', 'stack', 'stl_alloc.h', 'stl_relops.h', 'type_traits.h', 'utility', 'vector', 'vector.h', ]) # Non-STL C++ system headers. _CPP_HEADERS = frozenset([ 'algo.h', 'builtinbuf.h', 'bvector.h', 'cassert', 'cctype', 'cerrno', 'cfloat', 'ciso646', 'climits', 'clocale', 'cmath', 'complex', 'complex.h', 'csetjmp', 'csignal', 'cstdarg', 'cstddef', 'cstdio', 'cstdlib', 'cstring', 'ctime', 'cwchar', 'cwctype', 'defalloc.h', 'deque.h', 'editbuf.h', 'exception', 'fstream', 'fstream.h', 'hashtable.h', 'heap.h', 'indstream.h', 'iomanip', 'iomanip.h', 'ios', 'iosfwd', 'iostream', 'iostream.h', 'istream.h', 'iterator.h', 'limits', 'map.h', 'multimap.h', 'multiset.h', 'numeric', 'ostream.h', 'parsestream.h', 'pfstream.h', 'PlotFile.h', 'procbuf.h', 'pthread_alloc.h', 'rope', 'rope.h', 'ropeimpl.h', 'SFile.h', 'slist', 'slist.h', 'stack.h', 'stdexcept', 'stdiostream.h', 'streambuf.h', 'stream.h', 'strfile.h', 'string', 'strstream', 'strstream.h', 'tempbuf.h', 'tree.h', 'typeinfo', 'valarray', ]) # Assertion macros. These are defined in base/logging.h and # testing/base/gunit.h. Note that the _M versions need to come first # for substring matching to work. _CHECK_MACROS = [ 'DCHECK', 'CHECK', 'EXPECT_TRUE_M', 'EXPECT_TRUE', 'ASSERT_TRUE_M', 'ASSERT_TRUE', 'EXPECT_FALSE_M', 'EXPECT_FALSE', 'ASSERT_FALSE_M', 'ASSERT_FALSE', ] # Replacement macros for CHECK/DCHECK/EXPECT_TRUE/EXPECT_FALSE _CHECK_REPLACEMENT = dict([(m, {}) for m in _CHECK_MACROS]) for op, replacement in [('==', 'EQ'), ('!=', 'NE'), ('>=', 'GE'), ('>', 'GT'), ('<=', 'LE'), ('<', 'LT')]: _CHECK_REPLACEMENT['DCHECK'][op] = 'DCHECK_%s' % replacement _CHECK_REPLACEMENT['CHECK'][op] = 'CHECK_%s' % replacement _CHECK_REPLACEMENT['EXPECT_TRUE'][op] = 'EXPECT_%s' % replacement _CHECK_REPLACEMENT['ASSERT_TRUE'][op] = 'ASSERT_%s' % replacement _CHECK_REPLACEMENT['EXPECT_TRUE_M'][op] = 'EXPECT_%s_M' % replacement _CHECK_REPLACEMENT['ASSERT_TRUE_M'][op] = 'ASSERT_%s_M' % replacement for op, inv_replacement in [('==', 'NE'), ('!=', 'EQ'), ('>=', 'LT'), ('>', 'LE'), ('<=', 'GT'), ('<', 'GE')]: _CHECK_REPLACEMENT['EXPECT_FALSE'][op] = 'EXPECT_%s' % inv_replacement _CHECK_REPLACEMENT['ASSERT_FALSE'][op] = 'ASSERT_%s' % inv_replacement _CHECK_REPLACEMENT['EXPECT_FALSE_M'][op] = 'EXPECT_%s_M' % inv_replacement _CHECK_REPLACEMENT['ASSERT_FALSE_M'][op] = 'ASSERT_%s_M' % inv_replacement # These constants define types of headers for use with # _IncludeState.check_next_include_order(). _CONFIG_HEADER = 0 _PRIMARY_HEADER = 1 _OTHER_HEADER = 2 _regexp_compile_cache = {} def match(pattern, s): """Matches the string with the pattern, caching the compiled regexp.""" # The regexp compilation caching is inlined in both match and search for # performance reasons; factoring it out into a separate function turns out # to be noticeably expensive. if not pattern in _regexp_compile_cache: _regexp_compile_cache[pattern] = sre_compile.compile(pattern) return _regexp_compile_cache[pattern].match(s) def search(pattern, s): """Searches the string for the pattern, caching the compiled regexp.""" if not pattern in _regexp_compile_cache: _regexp_compile_cache[pattern] = sre_compile.compile(pattern) return _regexp_compile_cache[pattern].search(s) class _IncludeState(dict): """Tracks line numbers for includes, and the order in which includes appear. As a dict, an _IncludeState object serves as a mapping between include filename and line number on which that file was included. Call check_next_include_order() once for each header in the file, passing in the type constants defined above. Calls in an illegal order will raise an _IncludeError with an appropriate error message. """ # self._section will move monotonically through this set. If it ever # needs to move backwards, check_next_include_order will raise an error. _INITIAL_SECTION = 0 _CONFIG_SECTION = 1 _PRIMARY_SECTION = 2 _OTHER_SECTION = 3 _TYPE_NAMES = { _CONFIG_HEADER: 'WebCore config.h', _PRIMARY_HEADER: 'header this file implements', _OTHER_HEADER: 'other header', } _SECTION_NAMES = { _INITIAL_SECTION: "... nothing.", _CONFIG_SECTION: "WebCore config.h.", _PRIMARY_SECTION: 'a header this file implements.', _OTHER_SECTION: 'other header.', } def __init__(self): dict.__init__(self) self._section = self._INITIAL_SECTION self._visited_primary_section = False self.header_types = dict(); def visited_primary_section(self): return self._visited_primary_section def check_next_include_order(self, header_type, file_is_header): """Returns a non-empty error message if the next header is out of order. This function also updates the internal state to be ready to check the next include. Args: header_type: One of the _XXX_HEADER constants defined above. file_is_header: Whether the file that owns this _IncludeState is itself a header Returns: The empty string if the header is in the right order, or an error message describing what's wrong. """ if header_type == _CONFIG_HEADER and file_is_header: return 'Header file should not contain WebCore config.h.' if header_type == _PRIMARY_HEADER and file_is_header: return 'Header file should not contain itself.' error_message = '' if self._section != self._OTHER_SECTION: before_error_message = ('Found %s before %s' % (self._TYPE_NAMES[header_type], self._SECTION_NAMES[self._section + 1])) after_error_message = ('Found %s after %s' % (self._TYPE_NAMES[header_type], self._SECTION_NAMES[self._section])) if header_type == _CONFIG_HEADER: if self._section >= self._CONFIG_SECTION: error_message = after_error_message self._section = self._CONFIG_SECTION elif header_type == _PRIMARY_HEADER: if self._section >= self._PRIMARY_SECTION: error_message = after_error_message elif self._section < self._CONFIG_SECTION: error_message = before_error_message self._section = self._PRIMARY_SECTION self._visited_primary_section = True else: assert header_type == _OTHER_HEADER if not file_is_header and self._section < self._PRIMARY_SECTION: error_message = before_error_message self._section = self._OTHER_SECTION return error_message class _CppLintState(object): """Maintains module-wide state..""" def __init__(self): self.verbose_level = 1 # global setting. self.error_count = 0 # global count of reported errors # filters to apply when emitting error messages self.filters = _DEFAULT_FILTERS[:] # output format: # "emacs" - format that emacs can parse (default) # "vs7" - format that Microsoft Visual Studio 7 can parse self.output_format = 'emacs' self.output_stream = sys.stderr def set_output_format(self, output_format): """Sets the output format for errors.""" self.output_format = output_format def set_verbose_level(self, level): """Sets the module's verbosity, and returns the previous setting.""" last_verbose_level = self.verbose_level self.verbose_level = level return last_verbose_level def set_filters(self, filters): """Sets the error-message filters. These filters are applied when deciding whether to emit a given error message. Args: filters: A string of comma-separated filters (eg "+whitespace/indent"). Each filter should start with + or -; else we die. Raises: ValueError: The comma-separated filters did not all start with '+' or '-'. E.g. "-,+whitespace,-whitespace/indent,whitespace/badfilter" """ # Default filters always have less priority than the flag ones. self.filters = _DEFAULT_FILTERS[:] for filter in filters.split(','): clean_filter = filter.strip() if clean_filter: self.filters.append(clean_filter) for filter in self.filters: if not (filter.startswith('+') or filter.startswith('-')): raise ValueError('Every filter in --filter must start with ' '+ or - (%s does not)' % filter) def reset_error_count(self): """Sets the module's error statistic back to zero.""" self.error_count = 0 def increment_error_count(self): """Bumps the module's error statistic.""" self.error_count += 1 def set_stream(self, stream): self.output_stream = stream def write_error(self, error): self.output_stream.write(error) _cpplint_state = _CppLintState() def _output_format(): """Gets the module's output format.""" return _cpplint_state.output_format def _set_output_format(output_format): """Sets the module's output format.""" _cpplint_state.set_output_format(output_format) def _verbose_level(): """Returns the module's verbosity setting.""" return _cpplint_state.verbose_level def _set_verbose_level(level): """Sets the module's verbosity, and returns the previous setting.""" return _cpplint_state.set_verbose_level(level) def _filters(): """Returns the module's list of output filters, as a list.""" return _cpplint_state.filters def _set_filters(filters): """Sets the module's error-message filters. These filters are applied when deciding whether to emit a given error message. Args: filters: A string of comma-separated filters (eg "whitespace/indent"). Each filter should start with + or -; else we die. """ _cpplint_state.set_filters(filters) def error_count(): """Returns the global count of reported errors.""" return _cpplint_state.error_count class _FunctionState(object): """Tracks current function name and the number of lines in its body.""" _NORMAL_TRIGGER = 250 # for --v=0, 500 for --v=1, etc. _TEST_TRIGGER = 400 # about 50% more than _NORMAL_TRIGGER. def __init__(self): self.in_a_function = False self.lines_in_function = 0 self.current_function = '' def begin(self, function_name): """Start analyzing function body. Args: function_name: The name of the function being tracked. """ self.in_a_function = True self.lines_in_function = 0 self.current_function = function_name def count(self): """Count line in current function body.""" if self.in_a_function: self.lines_in_function += 1 def check(self, error, filename, line_number): """Report if too many lines in function body. Args: error: The function to call with any errors found. filename: The name of the current file. line_number: The number of the line to check. """ if match(r'T(EST|est)', self.current_function): base_trigger = self._TEST_TRIGGER else: base_trigger = self._NORMAL_TRIGGER trigger = base_trigger * 2 ** _verbose_level() if self.lines_in_function > trigger: error_level = int(math.log(self.lines_in_function / base_trigger, 2)) # 50 => 0, 100 => 1, 200 => 2, 400 => 3, 800 => 4, 1600 => 5, ... if error_level > 5: error_level = 5 error(filename, line_number, 'readability/fn_size', error_level, 'Small and focused functions are preferred:' ' %s has %d non-comment lines' ' (error triggered by exceeding %d lines).' % ( self.current_function, self.lines_in_function, trigger)) def end(self): """Stop analizing function body.""" self.in_a_function = False class _IncludeError(Exception): """Indicates a problem with the include order in a file.""" pass class FileInfo: """Provides utility functions for filenames. FileInfo provides easy access to the components of a file's path relative to the project root. """ def __init__(self, filename): self._filename = filename def full_name(self): """Make Windows paths like Unix.""" return os.path.abspath(self._filename).replace('\\', '/') def repository_name(self): """Full name after removing the local path to the repository. If we have a real absolute path name here we can try to do something smart: detecting the root of the checkout and truncating /path/to/checkout from the name so that we get header guards that don't include things like "C:\Documents and Settings\..." or "/home/username/..." in them and thus people on different computers who have checked the source out to different locations won't see bogus errors. """ fullname = self.full_name() if os.path.exists(fullname): project_dir = os.path.dirname(fullname) if os.path.exists(os.path.join(project_dir, ".svn")): # If there's a .svn file in the current directory, we # recursively look up the directory tree for the top # of the SVN checkout root_dir = project_dir one_up_dir = os.path.dirname(root_dir) while os.path.exists(os.path.join(one_up_dir, ".svn")): root_dir = os.path.dirname(root_dir) one_up_dir = os.path.dirname(one_up_dir) prefix = os.path.commonprefix([root_dir, project_dir]) return fullname[len(prefix) + 1:] # Not SVN? Try to find a git top level directory by # searching up from the current path. root_dir = os.path.dirname(fullname) while (root_dir != os.path.dirname(root_dir) and not os.path.exists(os.path.join(root_dir, ".git"))): root_dir = os.path.dirname(root_dir) if os.path.exists(os.path.join(root_dir, ".git")): prefix = os.path.commonprefix([root_dir, project_dir]) return fullname[len(prefix) + 1:] # Don't know what to do; header guard warnings may be wrong... return fullname def split(self): """Splits the file into the directory, basename, and extension. For 'chrome/browser/browser.cpp', Split() would return ('chrome/browser', 'browser', '.cpp') Returns: A tuple of (directory, basename, extension). """ googlename = self.repository_name() project, rest = os.path.split(googlename) return (project,) + os.path.splitext(rest) def base_name(self): """File base name - text after the final slash, before the final period.""" return self.split()[1] def extension(self): """File extension - text following the final period.""" return self.split()[2] def no_extension(self): """File has no source file extension.""" return '/'.join(self.split()[0:2]) def is_source(self): """File has a source file extension.""" return self.extension()[1:] in ('c', 'cc', 'cpp', 'cxx') def _should_print_error(category, confidence): """Returns true iff confidence >= verbose, and category passes filter.""" # There are two ways we might decide not to print an error message: # the verbosity level isn't high enough, or the filters filter it out. if confidence < _cpplint_state.verbose_level: return False is_filtered = False for one_filter in _filters(): if one_filter.startswith('-'): if category.startswith(one_filter[1:]): is_filtered = True elif one_filter.startswith('+'): if category.startswith(one_filter[1:]): is_filtered = False else: assert False # should have been checked for in set_filter. if is_filtered: return False return True def error(filename, line_number, category, confidence, message): """Logs the fact we've found a lint error. We log where the error was found, and also our confidence in the error, that is, how certain we are this is a legitimate style regression, and not a misidentification or a use that's sometimes justified. Args: filename: The name of the file containing the error. line_number: The number of the line containing the error. category: A string used to describe the "category" this bug falls under: "whitespace", say, or "runtime". Categories may have a hierarchy separated by slashes: "whitespace/indent". confidence: A number from 1-5 representing a confidence score for the error, with 5 meaning that we are certain of the problem, and 1 meaning that it could be a legitimate construct. message: The error message. """ # There are two ways we might decide not to print an error message: # the verbosity level isn't high enough, or the filters filter it out. if _should_print_error(category, confidence): _cpplint_state.increment_error_count() if _cpplint_state.output_format == 'vs7': write_error('%s(%s): %s [%s] [%d]\n' % ( filename, line_number, message, category, confidence)) else: write_error('%s:%s: %s [%s] [%d]\n' % ( filename, line_number, message, category, confidence)) # Matches standard C++ escape esequences per 2.13.2.3 of the C++ standard. _RE_PATTERN_CLEANSE_LINE_ESCAPES = re.compile( r'\\([abfnrtv?"\\\']|\d+|x[0-9a-fA-F]+)') # Matches strings. Escape codes should already be removed by ESCAPES. _RE_PATTERN_CLEANSE_LINE_DOUBLE_QUOTES = re.compile(r'"[^"]*"') # Matches characters. Escape codes should already be removed by ESCAPES. _RE_PATTERN_CLEANSE_LINE_SINGLE_QUOTES = re.compile(r"'.'") # Matches multi-line C++ comments. # This RE is a little bit more complicated than one might expect, because we # have to take care of space removals tools so we can handle comments inside # statements better. # The current rule is: We only clear spaces from both sides when we're at the # end of the line. Otherwise, we try to remove spaces from the right side, # if this doesn't work we try on left side but only if there's a non-character # on the right. _RE_PATTERN_CLEANSE_LINE_C_COMMENTS = re.compile( r"""(\s*/\*.*\*/\s*$| /\*.*\*/\s+| \s+/\*.*\*/(?=\W)| /\*.*\*/)""", re.VERBOSE) def is_cpp_string(line): """Does line terminate so, that the next symbol is in string constant. This function does not consider single-line nor multi-line comments. Args: line: is a partial line of code starting from the 0..n. Returns: True, if next character appended to 'line' is inside a string constant. """ line = line.replace(r'\\', 'XX') # after this, \\" does not match to \" return ((line.count('"') - line.count(r'\"') - line.count("'\"'")) & 1) == 1 def find_next_multi_line_comment_start(lines, line_index): """Find the beginning marker for a multiline comment.""" while line_index < len(lines): if lines[line_index].strip().startswith('/*'): # Only return this marker if the comment goes beyond this line if lines[line_index].strip().find('*/', 2) < 0: return line_index line_index += 1 return len(lines) def find_next_multi_line_comment_end(lines, line_index): """We are inside a comment, find the end marker.""" while line_index < len(lines): if lines[line_index].strip().endswith('*/'): return line_index line_index += 1 return len(lines) def remove_multi_line_comments_from_range(lines, begin, end): """Clears a range of lines for multi-line comments.""" # Having // dummy comments makes the lines non-empty, so we will not get # unnecessary blank line warnings later in the code. for i in range(begin, end): lines[i] = '// dummy' def remove_multi_line_comments(filename, lines, error): """Removes multiline (c-style) comments from lines.""" line_index = 0 while line_index < len(lines): line_index_begin = find_next_multi_line_comment_start(lines, line_index) if line_index_begin >= len(lines): return line_index_end = find_next_multi_line_comment_end(lines, line_index_begin) if line_index_end >= len(lines): error(filename, line_index_begin + 1, 'readability/multiline_comment', 5, 'Could not find end of multi-line comment') return remove_multi_line_comments_from_range(lines, line_index_begin, line_index_end + 1) line_index = line_index_end + 1 def cleanse_comments(line): """Removes //-comments and single-line C-style /* */ comments. Args: line: A line of C++ source. Returns: The line with single-line comments removed. """ comment_position = line.find('//') if comment_position != -1 and not is_cpp_string(line[:comment_position]): line = line[:comment_position] # get rid of /* ... */ return _RE_PATTERN_CLEANSE_LINE_C_COMMENTS.sub('', line) class CleansedLines(object): """Holds 3 copies of all lines with different preprocessing applied to them. 1) elided member contains lines without strings and comments, 2) lines member contains lines without comments, and 3) raw member contains all the lines without processing. All these three members are of , and of the same length. """ def __init__(self, lines): self.elided = [] self.lines = [] self.raw_lines = lines self._num_lines = len(lines) for line_number in range(len(lines)): self.lines.append(cleanse_comments(lines[line_number])) elided = self.collapse_strings(lines[line_number]) self.elided.append(cleanse_comments(elided)) def num_lines(self): """Returns the number of lines represented.""" return self._num_lines @staticmethod def collapse_strings(elided): """Collapses strings and chars on a line to simple "" or '' blocks. We nix strings first so we're not fooled by text like '"http://"' Args: elided: The line being processed. Returns: The line with collapsed strings. """ if not _RE_PATTERN_INCLUDE.match(elided): # Remove escaped characters first to make quote/single quote collapsing # basic. Things that look like escaped characters shouldn't occur # outside of strings and chars. elided = _RE_PATTERN_CLEANSE_LINE_ESCAPES.sub('', elided) elided = _RE_PATTERN_CLEANSE_LINE_SINGLE_QUOTES.sub("''", elided) elided = _RE_PATTERN_CLEANSE_LINE_DOUBLE_QUOTES.sub('""', elided) return elided def close_expression(clean_lines, line_number, pos): """If input points to ( or { or [, finds the position that closes it. If lines[line_number][pos] points to a '(' or '{' or '[', finds the the line_number/pos that correspond to the closing of the expression. Args: clean_lines: A CleansedLines instance containing the file. line_number: The number of the line to check. pos: A position on the line. Returns: A tuple (line, line_number, pos) pointer *past* the closing brace, or (line, len(lines), -1) if we never find a close. Note we ignore strings and comments when matching; and the line we return is the 'cleansed' line at line_number. """ line = clean_lines.elided[line_number] start_character = line[pos] if start_character not in '({[': return (line, clean_lines.num_lines(), -1) if start_character == '(': end_character = ')' if start_character == '[': end_character = ']' if start_character == '{': end_character = '}' num_open = line.count(start_character) - line.count(end_character) while line_number < clean_lines.num_lines() and num_open > 0: line_number += 1 line = clean_lines.elided[line_number] num_open += line.count(start_character) - line.count(end_character) # OK, now find the end_character that actually got us back to even endpos = len(line) while num_open >= 0: endpos = line.rfind(')', 0, endpos) num_open -= 1 # chopped off another ) return (line, line_number, endpos + 1) def check_for_copyright(filename, lines, error): """Logs an error if no Copyright message appears at the top of the file.""" # We'll say it should occur by line 10. Don't forget there's a # dummy line at the front. for line in xrange(1, min(len(lines), 11)): if re.search(r'Copyright|License', lines[line], re.I): break else: # means no copyright line was found error(filename, 1, 'legal/copyright', 3, 'No copyright message found.') def get_header_guard_cpp_variable(filename): """Returns the CPP variable that should be used as a header guard. Args: filename: The name of a C++ header file. Returns: The CPP variable that should be used as a header guard in the named file. """ fileinfo = FileInfo(filename) return re.sub(r'[-./\s]', '_', fileinfo.repository_name()).upper() + '_' def check_for_header_guard(filename, lines, error): """Checks that the file contains a header guard. Logs an error if no #ifndef header guard is present. For other headers, checks that the full pathname is used. Args: filename: The name of the C++ header file. lines: An array of strings, each representing a line of the file. error: The function to call with any errors found. """ cppvar = get_header_guard_cpp_variable(filename) ifndef = None ifndef_line_number = 0 define = None endif = None endif_line_number = 0 for line_number, line in enumerate(lines): line_split = line.split() if len(line_split) >= 2: # find the first occurrence of #ifndef and #define, save arg if not ifndef and line_split[0] == '#ifndef': # set ifndef to the header guard presented on the #ifndef line. ifndef = line_split[1] ifndef_line_number = line_number if not define and line_split[0] == '#define': define = line_split[1] # find the last occurrence of #endif, save entire line if line.startswith('#endif'): endif = line endif_line_number = line_number if not ifndef or not define or ifndef != define: error(filename, 1, 'build/header_guard', 5, 'No #ifndef header guard found, suggested CPP variable is: %s' % cppvar) return # The guard should be PATH_FILE_H_, but we also allow PATH_FILE_H__ # for backward compatibility. if ifndef != cppvar: error_level = 0 if ifndef != cppvar + '_': error_level = 5 error(filename, ifndef_line_number, 'build/header_guard', error_level, '#ifndef header guard has wrong style, please use: %s' % cppvar) if endif != ('#endif // %s' % cppvar): error_level = 0 if endif != ('#endif // %s' % (cppvar + '_')): error_level = 5 error(filename, endif_line_number, 'build/header_guard', error_level, '#endif line should be "#endif // %s"' % cppvar) def check_for_unicode_replacement_characters(filename, lines, error): """Logs an error for each line containing Unicode replacement characters. These indicate that either the file contained invalid UTF-8 (likely) or Unicode replacement characters (which it shouldn't). Note that it's possible for this to throw off line numbering if the invalid UTF-8 occurred adjacent to a newline. Args: filename: The name of the current file. lines: An array of strings, each representing a line of the file. error: The function to call with any errors found. """ for line_number, line in enumerate(lines): if u'\ufffd' in line: error(filename, line_number, 'readability/utf8', 5, 'Line contains invalid UTF-8 (or Unicode replacement character).') def check_for_new_line_at_eof(filename, lines, error): """Logs an error if there is no newline char at the end of the file. Args: filename: The name of the current file. lines: An array of strings, each representing a line of the file. error: The function to call with any errors found. """ # The array lines() was created by adding two newlines to the # original file (go figure), then splitting on \n. # To verify that the file ends in \n, we just have to make sure the # last-but-two element of lines() exists and is empty. if len(lines) < 3 or lines[-2]: error(filename, len(lines) - 2, 'whitespace/ending_newline', 5, 'Could not find a newline character at the end of the file.') def check_for_multiline_comments_and_strings(filename, clean_lines, line_number, error): """Logs an error if we see /* ... */ or "..." that extend past one line. /* ... */ comments are legit inside macros, for one line. Otherwise, we prefer // comments, so it's ok to warn about the other. Likewise, it's ok for strings to extend across multiple lines, as long as a line continuation character (backslash) terminates each line. Although not currently prohibited by the C++ style guide, it's ugly and unnecessary. We don't do well with either in this lint program, so we warn about both. Args: filename: The name of the current file. clean_lines: A CleansedLines instance containing the file. line_number: The number of the line to check. error: The function to call with any errors found. """ line = clean_lines.elided[line_number] # Remove all \\ (escaped backslashes) from the line. They are OK, and the # second (escaped) slash may trigger later \" detection erroneously. line = line.replace('\\\\', '') if line.count('/*') > line.count('*/'): error(filename, line_number, 'readability/multiline_comment', 5, 'Complex multi-line /*...*/-style comment found. ' 'Lint may give bogus warnings. ' 'Consider replacing these with //-style comments, ' 'with #if 0...#endif, ' 'or with more clearly structured multi-line comments.') if (line.count('"') - line.count('\\"')) % 2: error(filename, line_number, 'readability/multiline_string', 5, 'Multi-line string ("...") found. This lint script doesn\'t ' 'do well with such strings, and may give bogus warnings. They\'re ' 'ugly and unnecessary, and you should use concatenation instead".') _THREADING_LIST = ( ('asctime(', 'asctime_r('), ('ctime(', 'ctime_r('), ('getgrgid(', 'getgrgid_r('), ('getgrnam(', 'getgrnam_r('), ('getlogin(', 'getlogin_r('), ('getpwnam(', 'getpwnam_r('), ('getpwuid(', 'getpwuid_r('), ('gmtime(', 'gmtime_r('), ('localtime(', 'localtime_r('), ('rand(', 'rand_r('), ('readdir(', 'readdir_r('), ('strtok(', 'strtok_r('), ('ttyname(', 'ttyname_r('), ) def check_posix_threading(filename, clean_lines, line_number, error): """Checks for calls to thread-unsafe functions. Much code has been originally written without consideration of multi-threading. Also, engineers are relying on their old experience; they have learned posix before threading extensions were added. These tests guide the engineers to use thread-safe functions (when using posix directly). Args: filename: The name of the current file. clean_lines: A CleansedLines instance containing the file. line_number: The number of the line to check. error: The function to call with any errors found. """ line = clean_lines.elided[line_number] for single_thread_function, multithread_safe_function in _THREADING_LIST: index = line.find(single_thread_function) # Comparisons made explicit for clarity -- pylint: disable-msg=C6403 if index >= 0 and (index == 0 or (not line[index - 1].isalnum() and line[index - 1] not in ('_', '.', '>'))): error(filename, line_number, 'runtime/threadsafe_fn', 2, 'Consider using ' + multithread_safe_function + '...) instead of ' + single_thread_function + '...) for improved thread safety.') # Matches invalid increment: *count++, which moves pointer instead of # incrementing a value. _RE_PATTERN_INVALID_INCREMENT = re.compile( r'^\s*\*\w+(\+\+|--);') def check_invalid_increment(filename, clean_lines, line_number, error): """Checks for invalid increment *count++. For example following function: void increment_counter(int* count) { *count++; } is invalid, because it effectively does count++, moving pointer, and should be replaced with ++*count, (*count)++ or *count += 1. Args: filename: The name of the current file. clean_lines: A CleansedLines instance containing the file. line_number: The number of the line to check. error: The function to call with any errors found. """ line = clean_lines.elided[line_number] if _RE_PATTERN_INVALID_INCREMENT.match(line): error(filename, line_number, 'runtime/invalid_increment', 5, 'Changing pointer instead of value (or unused value of operator*).') class _ClassInfo(object): """Stores information about a class.""" def __init__(self, name, line_number): self.name = name self.line_number = line_number self.seen_open_brace = False self.is_derived = False self.virtual_method_line_number = None self.has_virtual_destructor = False self.brace_depth = 0 class _ClassState(object): """Holds the current state of the parse relating to class declarations. It maintains a stack of _ClassInfos representing the parser's guess as to the current nesting of class declarations. The innermost class is at the top (back) of the stack. Typically, the stack will either be empty or have exactly one entry. """ def __init__(self): self.classinfo_stack = [] def check_finished(self, filename, error): """Checks that all classes have been completely parsed. Call this when all lines in a file have been processed. Args: filename: The name of the current file. error: The function to call with any errors found. """ if self.classinfo_stack: # Note: This test can result in false positives if #ifdef constructs # get in the way of brace matching. See the testBuildClass test in # cpplint_unittest.py for an example of this. error(filename, self.classinfo_stack[0].line_number, 'build/class', 5, 'Failed to find complete declaration of class %s' % self.classinfo_stack[0].name) def check_for_non_standard_constructs(filename, clean_lines, line_number, class_state, error): """Logs an error if we see certain non-ANSI constructs ignored by gcc-2. Complain about several constructs which gcc-2 accepts, but which are not standard C++. Warning about these in lint is one way to ease the transition to new compilers. - put storage class first (e.g. "static const" instead of "const static"). - "%lld" instead of %qd" in printf-type functions. - "%1$d" is non-standard in printf-type functions. - "\%" is an undefined character escape sequence. - text after #endif is not allowed. - invalid inner-style forward declaration. - >? and ?= and )\?=?\s*(\w+|[+-]?\d+)(\.\d*)?', line): error(filename, line_number, 'build/deprecated', 3, '>? and ,:]*>\s*)?(class|struct)\s+(\w+(::\w+)*)', line) if class_decl_match: classinfo_stack.append(_ClassInfo(class_decl_match.group(3), line_number)) # Everything else in this function uses the top of the stack if it's # not empty. if not classinfo_stack: return classinfo = classinfo_stack[-1] # If the opening brace hasn't been seen look for it and also # parent class declarations. if not classinfo.seen_open_brace: # If the line has a ';' in it, assume it's a forward declaration or # a single-line class declaration, which we won't process. if line.find(';') != -1: classinfo_stack.pop() return classinfo.seen_open_brace = (line.find('{') != -1) # Look for a bare ':' if search('(^|[^:]):($|[^:])', line): classinfo.is_derived = True if not classinfo.seen_open_brace: return # Everything else in this function is for after open brace # The class may have been declared with namespace or classname qualifiers. # The constructor and destructor will not have those qualifiers. base_classname = classinfo.name.split('::')[-1] # Look for single-argument constructors that aren't marked explicit. # Technically a valid construct, but against style. args = match(r'(?= 0 and match(r' {6}\w', elided[search_position])): search_position -= 1 exception = (search_position >= 0 and elided[search_position][:5] == ' :') else: # Search for the function arguments or an initializer list. We use a # simple heuristic here: If the line is indented 4 spaces; and we have a # closing paren, without the opening paren, followed by an opening brace # or colon (for initializer lists) we assume that it is the last line of # a function header. If we have a colon indented 4 spaces, it is an # initializer list. exception = (match(r' {4}\w[^\(]*\)\s*(const\s*)?(\{\s*$|:)', previous_line) or match(r' {4}:', previous_line)) if not exception: error(filename, line_number, 'whitespace/blank_line', 2, 'Blank line at the start of a code block. Is this needed?') # This doesn't ignore whitespace at the end of a namespace block # because that is too hard without pairing open/close braces; # however, a special exception is made for namespace closing # brackets which have a comment containing "namespace". # # Also, ignore blank lines at the end of a block in a long if-else # chain, like this: # if (condition1) { # // Something followed by a blank line # # } else if (condition2) { # // Something else # } if line_number + 1 < clean_lines.num_lines(): next_line = raw[line_number + 1] if (next_line and match(r'\s*}', next_line) and next_line.find('namespace') == -1 and next_line.find('} else ') == -1): error(filename, line_number, 'whitespace/blank_line', 3, 'Blank line at the end of a code block. Is this needed?') # Next, we complain if there's a comment too near the text comment_position = line.find('//') if comment_position != -1: # Check if the // may be in quotes. If so, ignore it # Comparisons made explicit for clarity -- pylint: disable-msg=C6403 if (line.count('"', 0, comment_position) - line.count('\\"', 0, comment_position)) % 2 == 0: # not in quotes # Allow one space for new scopes, two spaces otherwise: if (not match(r'^\s*{ //', line) and ((comment_position >= 1 and line[comment_position-1] not in string.whitespace) or (comment_position >= 2 and line[comment_position-2] not in string.whitespace))): error(filename, line_number, 'whitespace/comments-doublespace', 2, 'At least two spaces is best between code and comments') # There should always be a space between the // and the comment commentend = comment_position + 2 if commentend < len(line) and not line[commentend] == ' ': # but some lines are exceptions -- e.g. if they're big # comment delimiters like: # //---------------------------------------------------------- # or they begin with multiple slashes followed by a space: # //////// Header comment matched = (search(r'[=/-]{4,}\s*$', line[commentend:]) or search(r'^/+ ', line[commentend:])) if not matched: error(filename, line_number, 'whitespace/comments', 4, 'Should have a space between // and comment') line = clean_lines.elided[line_number] # get rid of comments and strings # Don't try to do spacing checks for operator methods line = re.sub(r'operator(==|!=|<|<<|<=|>=|>>|>)\(', 'operator\(', line) # We allow no-spaces around = within an if: "if ( (a=Foo()) == 0 )". # Otherwise not. Note we only check for non-spaces on *both* sides; # sometimes people put non-spaces on one side when aligning ='s among # many lines (not that this is behavior that I approve of...) if search(r'[\w.]=[\w.]', line) and not search(r'\b(if|while) ', line): error(filename, line_number, 'whitespace/operators', 4, 'Missing spaces around =') # FIXME: It's not ok to have spaces around binary operators like + - * / . # You should always have whitespace around binary operators. # Alas, we can't test < or > because they're legitimately used sans spaces # (a->b, vector a). The only time we can tell is a < with no >, and # only if it's not template params list spilling into the next line. matched = search(r'[^<>=!\s](==|!=|<=|>=)[^<>=!\s]', line) if not matched: # Note that while it seems that the '<[^<]*' term in the following # regexp could be simplified to '<.*', which would indeed match # the same class of strings, the [^<] means that searching for the # regexp takes linear rather than quadratic time. if not search(r'<[^<]*,\s*$', line): # template params spill matched = search(r'[^<>=!\s](<)[^<>=!\s]([^>]|->)*$', line) if matched: error(filename, line_number, 'whitespace/operators', 3, 'Missing spaces around %s' % matched.group(1)) # We allow no-spaces around << and >> when used like this: 10<<20, but # not otherwise (particularly, not when used as streams) matched = search(r'[^0-9\s](<<|>>)[^0-9\s]', line) if matched: error(filename, line_number, 'whitespace/operators', 3, 'Missing spaces around %s' % matched.group(1)) # There shouldn't be space around unary operators matched = search(r'(!\s|~\s|[\s]--[\s;]|[\s]\+\+[\s;])', line) if matched: error(filename, line_number, 'whitespace/operators', 4, 'Extra space for operator %s' % matched.group(1)) # A pet peeve of mine: no spaces after an if, while, switch, or for matched = search(r' (if\(|for\(|foreach\(|while\(|switch\()', line) if matched: error(filename, line_number, 'whitespace/parens', 5, 'Missing space before ( in %s' % matched.group(1)) # For if/for/foreach/while/switch, the left and right parens should be # consistent about how many spaces are inside the parens, and # there should either be zero or one spaces inside the parens. # We don't want: "if ( foo)" or "if ( foo )". # Exception: "for ( ; foo; bar)" and "for (foo; bar; )" are allowed. matched = search(r'\b(if|for|foreach|while|switch)\s*\(([ ]*)(.).*[^ ]+([ ]*)\)\s*{\s*$', line) if matched: if len(matched.group(2)) != len(matched.group(4)): if not (matched.group(3) == ';' and len(matched.group(2)) == 1 + len(matched.group(4)) or not matched.group(2) and search(r'\bfor\s*\(.*; \)', line)): error(filename, line_number, 'whitespace/parens', 5, 'Mismatching spaces inside () in %s' % matched.group(1)) if not len(matched.group(2)) in [0, 1]: error(filename, line_number, 'whitespace/parens', 5, 'Should have zero or one spaces inside ( and ) in %s' % matched.group(1)) # You should always have a space after a comma (either as fn arg or operator) if search(r',[^\s]', line): error(filename, line_number, 'whitespace/comma', 3, 'Missing space after ,') # Next we will look for issues with function calls. check_spacing_for_function_call(filename, line, line_number, error) # Except after an opening paren, you should have spaces before your braces. # And since you should never have braces at the beginning of a line, this is # an easy test. if search(r'[^ ({]{', line): error(filename, line_number, 'whitespace/braces', 5, 'Missing space before {') # Make sure '} else {' has spaces. if search(r'}else', line): error(filename, line_number, 'whitespace/braces', 5, 'Missing space before else') # You shouldn't have spaces before your brackets, except maybe after # 'delete []' or 'new char * []'. if search(r'\w\s+\[', line) and not search(r'delete\s+\[', line): error(filename, line_number, 'whitespace/braces', 5, 'Extra space before [') # You shouldn't have a space before a semicolon at the end of the line. # There's a special case for "for" since the style guide allows space before # the semicolon there. if search(r':\s*;\s*$', line): error(filename, line_number, 'whitespace/semicolon', 5, 'Semicolon defining empty statement. Use { } instead.') elif search(r'^\s*;\s*$', line): error(filename, line_number, 'whitespace/semicolon', 5, 'Line contains only semicolon. If this should be an empty statement, ' 'use { } instead.') elif (search(r'\s+;\s*$', line) and not search(r'\bfor\b', line)): error(filename, line_number, 'whitespace/semicolon', 5, 'Extra space before last semicolon. If this should be an empty ' 'statement, use { } instead.') elif (search(r'\b(for|while)\s*\(.*\)\s*;\s*$', line) and line.count('(') == line.count(')') # Allow do {} while(); and not search(r'}\s*while', line)): error(filename, line_number, 'whitespace/semicolon', 5, 'Semicolon defining empty statement for this loop. Use { } instead.') def get_previous_non_blank_line(clean_lines, line_number): """Return the most recent non-blank line and its line number. Args: clean_lines: A CleansedLines instance containing the file contents. line_number: The number of the line to check. Returns: A tuple with two elements. The first element is the contents of the last non-blank line before the current line, or the empty string if this is the first non-blank line. The second is the line number of that line, or -1 if this is the first non-blank line. """ previous_line_number = line_number - 1 while previous_line_number >= 0: previous_line = clean_lines.elided[previous_line_number] if not is_blank_line(previous_line): # if not a blank line... return (previous_line, previous_line_number) previous_line_number -= 1 return ('', -1) def check_namespace_indentation(filename, clean_lines, line_number, file_extension, error): """Looks for indentation errors inside of namespaces. Args: filename: The name of the current file. clean_lines: A CleansedLines instance containing the file. line_number: The number of the line to check. file_extension: The extension (dot not included) of the file. error: The function to call with any errors found. """ line = clean_lines.elided[line_number] # Get rid of comments and strings. namespace_match = match(r'(?P\s*)namespace\s+\S+\s*{\s*$', line) if not namespace_match: return namespace_indentation = namespace_match.group('namespace_indentation') is_header_file = file_extension == 'h' is_implementation_file = not is_header_file line_offset = 0 if is_header_file: inner_indentation = namespace_indentation + ' ' * 4 for current_line in clean_lines.raw_lines[line_number + 1:]: line_offset += 1 # Skip not only empty lines but also those with preprocessor directives. # Goto labels don't occur in header files, so no need to check for those. if current_line.strip() == '' or current_line.startswith('#'): continue if not current_line.startswith(inner_indentation): # If something unindented was discovered, make sure it's a closing brace. if not current_line.startswith(namespace_indentation + '}'): error(filename, line_number + line_offset, 'whitespace/indent', 4, 'In a header, code inside a namespace should be indented.') break if is_implementation_file: for current_line in clean_lines.raw_lines[line_number + 1:]: line_offset += 1 # Skip not only empty lines but also those with (goto) labels. # The goto label regexp accepts spaces or the beginning of a # comment (if anything) after the initial colon. if current_line.strip() == '' or match(r'\w+\s*:([\s\/].*)?$', current_line): continue remaining_line = current_line[len(namespace_indentation):] if not match(r'\S', remaining_line): error(filename, line_number + line_offset, 'whitespace/indent', 4, 'In an implementation file, code inside a namespace should not be indented.') # Just check the first non-empty line in any case, because # otherwise we would need to count opened and closed braces, # which is obviously a lot more complicated. break def check_switch_indentation(filename, clean_lines, line_number, error): """Looks for indentation errors inside of switch statements. Args: filename: The name of the current file. clean_lines: A CleansedLines instance containing the file. line_number: The number of the line to check. error: The function to call with any errors found. """ line = clean_lines.elided[line_number] # Get rid of comments and strings. switch_match = match(r'(?P\s*)switch\s*\(.+\)\s*{\s*$', line) if not switch_match: return switch_indentation = switch_match.group('switch_indentation') inner_indentation = switch_indentation + ' ' * 4 line_offset = 0 encountered_nested_switch = False for current_line in clean_lines.elided[line_number + 1:]: line_offset += 1 # Skip not only empty lines but also those with preprocessor directives. if current_line.strip() == '' or current_line.startswith('#'): continue if match(r'\s*switch\s*\(.+\)\s*{\s*$', current_line): # Complexity alarm - another switch statement nested inside the one # that we're currently testing. We'll need to track the extent of # that inner switch if the upcoming label tests are still supposed # to work correctly. Let's not do that; instead, we'll finish # checking this line, and then leave it like that. Assuming the # indentation is done consistently (even if incorrectly), this will # still catch all indentation issues in practice. encountered_nested_switch = True current_indentation_match = match(r'(?P\s*)(?P.*)$', current_line); current_indentation = current_indentation_match.group('indentation') remaining_line = current_indentation_match.group('remaining_line') # End the check at the end of the switch statement. if remaining_line.startswith('}') and current_indentation == switch_indentation: break # Case and default branches should not be indented. The regexp also # catches single-line cases like "default: break;" but does not trigger # on stuff like "Document::Foo();". elif match(r'(default|case\s+.*)\s*:([^:].*)?$', remaining_line): if current_indentation != switch_indentation: error(filename, line_number + line_offset, 'whitespace/indent', 4, 'A case label should not be indented, but line up with its switch statement.') # Don't throw an error for multiple badly indented labels, # one should be enough to figure out the problem. break # We ignore goto labels at the very beginning of a line. elif match(r'\w+\s*:\s*$', remaining_line): continue # It's not a goto label, so check if it's indented at least as far as # the switch statement plus one more level of indentation. elif not current_indentation.startswith(inner_indentation): error(filename, line_number + line_offset, 'whitespace/indent', 4, 'Non-label code inside switch statements should be indented.') # Don't throw an error for multiple badly indented statements, # one should be enough to figure out the problem. break if encountered_nested_switch: break def check_braces(filename, clean_lines, line_number, error): """Looks for misplaced braces (e.g. at the end of line). Args: filename: The name of the current file. clean_lines: A CleansedLines instance containing the file. line_number: The number of the line to check. error: The function to call with any errors found. """ line = clean_lines.elided[line_number] # Get rid of comments and strings. """ These don't match our style guideline: https://developer.mozilla.org/en-US/docs/Developer_Guide/Coding_Style#Control_Structures TODO: Spin this off in a different rule and disable that rule for mozilla rather then commenting this out if match(r'\s*{\s*$', line): # We allow an open brace to start a line in the case where someone # is using braces for function definition or in a block to # explicitly create a new scope, which is commonly used to control # the lifetime of stack-allocated variables. We don't detect this # perfectly: we just don't complain if the last non-whitespace # character on the previous non-blank line is ';', ':', '{', '}', # ')', or ') const' and doesn't begin with 'if|for|while|switch|else'. # We also allow '#' for #endif and '=' for array initialization. previous_line = get_previous_non_blank_line(clean_lines, line_number)[0] if ((not search(r'[;:}{)=]\s*$|\)\s*const\s*$', previous_line) or search(r'\b(if|for|foreach|while|switch|else)\b', previous_line)) and previous_line.find('#') < 0): error(filename, line_number, 'whitespace/braces', 4, 'This { should be at the end of the previous line') elif (search(r'\)\s*(const\s*)?{\s*$', line) and line.count('(') == line.count(')') and not search(r'\b(if|for|foreach|while|switch)\b', line)): error(filename, line_number, 'whitespace/braces', 4, 'Place brace on its own line for function definitions.') if (match(r'\s*}\s*$', line) and line_number > 1): # We check if a closed brace has started a line to see if a # one line control statement was previous. previous_line = clean_lines.elided[line_number - 2] if (previous_line.find('{') > 0 and search(r'\b(if|for|foreach|while|else)\b', previous_line)): error(filename, line_number, 'whitespace/braces', 4, 'One line control clauses should not use braces.') """ # An else clause should be on the same line as the preceding closing brace. if match(r'\s*else\s*', line): previous_line = get_previous_non_blank_line(clean_lines, line_number)[0] if match(r'\s*}\s*$', previous_line): error(filename, line_number, 'whitespace/newline', 4, 'An else should appear on the same line as the preceding }') # Likewise, an else should never have the else clause on the same line if search(r'\belse [^\s{]', line) and not search(r'\belse if\b', line): error(filename, line_number, 'whitespace/newline', 4, 'Else clause should never be on same line as else (use 2 lines)') # In the same way, a do/while should never be on one line if match(r'\s*do [^\s{]', line): error(filename, line_number, 'whitespace/newline', 4, 'do/while clauses should not be on a single line') # Braces shouldn't be followed by a ; unless they're defining a struct # or initializing an array. # We can't tell in general, but we can for some common cases. previous_line_number = line_number while True: (previous_line, previous_line_number) = get_previous_non_blank_line(clean_lines, previous_line_number) if match(r'\s+{.*}\s*;', line) and not previous_line.count(';'): line = previous_line + line else: break if (search(r'{.*}\s*;', line) and line.count('{') == line.count('}') and not search(r'struct|class|enum|\s*=\s*{', line)): error(filename, line_number, 'readability/braces', 4, "You don't need a ; after a }") def check_exit_statement_simplifications(filename, clean_lines, line_number, error): """Looks for else or else-if statements that should be written as an if statement when the prior if concludes with a return, break, continue or goto statement. Args: filename: The name of the current file. clean_lines: A CleansedLines instance containing the file. line_number: The number of the line to check. error: The function to call with any errors found. """ line = clean_lines.elided[line_number] # Get rid of comments and strings. else_match = match(r'(?P\s*)(\}\s*)?else(\s+if\s*\(|(?P\s*(\{\s*)?\Z))', line) if not else_match: return else_indentation = else_match.group('else_indentation') inner_indentation = else_indentation + ' ' * 4 previous_lines = clean_lines.elided[:line_number] previous_lines.reverse() line_offset = 0 encountered_exit_statement = False for current_line in previous_lines: line_offset -= 1 # Skip not only empty lines but also those with preprocessor directives # and goto labels. if current_line.strip() == '' or current_line.startswith('#') or match(r'\w+\s*:\s*$', current_line): continue # Skip lines with closing braces on the original indentation level. # Even though the styleguide says they should be on the same line as # the "else if" statement, we also want to check for instances where # the current code does not comply with the coding style. Thus, ignore # these lines and proceed to the line before that. if current_line == else_indentation + '}': continue current_indentation_match = match(r'(?P\s*)(?P.*)$', current_line); current_indentation = current_indentation_match.group('indentation') remaining_line = current_indentation_match.group('remaining_line') # As we're going up the lines, the first real statement to encounter # has to be an exit statement (return, break, continue or goto) - # otherwise, this check doesn't apply. if not encountered_exit_statement: # We only want to find exit statements if they are on exactly # the same level of indentation as expected from the code inside # the block. If the indentation doesn't strictly match then we # might have a nested if or something, which must be ignored. if current_indentation != inner_indentation: break if match(r'(return(\W+.*)|(break|continue)\s*;|goto\s*\w+;)$', remaining_line): encountered_exit_statement = True continue break # When code execution reaches this point, we've found an exit statement # as last statement of the previous block. Now we only need to make # sure that the block belongs to an "if", then we can throw an error. # Skip lines with opening braces on the original indentation level, # similar to the closing braces check above. ("if (condition)\n{") if current_line == else_indentation + '{': continue # Skip everything that's further indented than our "else" or "else if". if current_indentation.startswith(else_indentation) and current_indentation != else_indentation: continue # So we've got a line with same (or less) indentation. Is it an "if"? # If yes: throw an error. If no: don't throw an error. # Whatever the outcome, this is the end of our loop. if match(r'if\s*\(', remaining_line): if else_match.start('else') != -1: error(filename, line_number + line_offset, 'readability/control_flow', 4, 'An else statement can be removed when the prior "if" ' 'concludes with a return, break, continue or goto statement.') else: error(filename, line_number + line_offset, 'readability/control_flow', 4, 'An else if statement should be written as an if statement ' 'when the prior "if" concludes with a return, break, ' 'continue or goto statement.') break def replaceable_check(operator, macro, line): """Determine whether a basic CHECK can be replaced with a more specific one. For example suggest using CHECK_EQ instead of CHECK(a == b) and similarly for CHECK_GE, CHECK_GT, CHECK_LE, CHECK_LT, CHECK_NE. Args: operator: The C++ operator used in the CHECK. macro: The CHECK or EXPECT macro being called. line: The current source line. Returns: True if the CHECK can be replaced with a more specific one. """ # This matches decimal and hex integers, strings, and chars (in that order). match_constant = r'([-+]?(\d+|0[xX][0-9a-fA-F]+)[lLuU]{0,3}|".*"|\'.*\')' # Expression to match two sides of the operator with something that # looks like a literal, since CHECK(x == iterator) won't compile. # This means we can't catch all the cases where a more specific # CHECK is possible, but it's less annoying than dealing with # extraneous warnings. match_this = (r'\s*' + macro + r'\((\s*' + match_constant + r'\s*' + operator + r'[^<>].*|' r'.*[^<>]' + operator + r'\s*' + match_constant + r'\s*\))') # Don't complain about CHECK(x == NULL) or similar because # CHECK_EQ(x, NULL) won't compile (requires a cast). # Also, don't complain about more complex boolean expressions # involving && or || such as CHECK(a == b || c == d). return match(match_this, line) and not search(r'NULL|&&|\|\|', line) def check_check(filename, clean_lines, line_number, error): """Checks the use of CHECK and EXPECT macros. Args: filename: The name of the current file. clean_lines: A CleansedLines instance containing the file. line_number: The number of the line to check. error: The function to call with any errors found. """ # Decide the set of replacement macros that should be suggested raw_lines = clean_lines.raw_lines current_macro = '' for macro in _CHECK_MACROS: if raw_lines[line_number].find(macro) >= 0: current_macro = macro break if not current_macro: # Don't waste time here if line doesn't contain 'CHECK' or 'EXPECT' return line = clean_lines.elided[line_number] # get rid of comments and strings # Encourage replacing plain CHECKs with CHECK_EQ/CHECK_NE/etc. for operator in ['==', '!=', '>=', '>', '<=', '<']: if replaceable_check(operator, current_macro, line): error(filename, line_number, 'readability/check', 2, 'Consider using %s instead of %s(a %s b)' % ( _CHECK_REPLACEMENT[current_macro][operator], current_macro, operator)) break def check_for_comparisons_to_zero(filename, clean_lines, line_number, error): # Get the line without comments and strings. line = clean_lines.elided[line_number] # Include NULL here so that users don't have to convert NULL to 0 first and then get this error. if search(r'[=!]=\s*(NULL|0|true|false)\W', line) or search(r'\W(NULL|0|true|false)\s*[=!]=', line): error(filename, line_number, 'readability/comparison_to_zero', 5, 'Tests for true/false, null/non-null, and zero/non-zero should all be done without equality comparisons.') def check_for_null(filename, clean_lines, line_number, error): # This check doesn't apply to C or Objective-C implementation files. if filename.endswith('.c') or filename.endswith('.m'): return line = clean_lines.elided[line_number] if search(r'\bNULL\b', line): error(filename, line_number, 'readability/null', 5, 'Use 0 instead of NULL.') return line = clean_lines.raw_lines[line_number] # See if NULL occurs in any comments in the line. If the search for NULL using the raw line # matches, then do the check with strings collapsed to avoid giving errors for # NULLs occurring in strings. if search(r'\bNULL\b', line) and search(r'\bNULL\b', CleansedLines.collapse_strings(line)): error(filename, line_number, 'readability/null', 4, 'Use 0 instead of NULL.') def get_line_width(line): """Determines the width of the line in column positions. Args: line: A string, which may be a Unicode string. Returns: The width of the line in column positions, accounting for Unicode combining characters and wide characters. """ if isinstance(line, unicode): width = 0 for c in unicodedata.normalize('NFC', line): if unicodedata.east_asian_width(c) in ('W', 'F'): width += 2 elif not unicodedata.combining(c): width += 1 return width return len(line) def check_style(filename, clean_lines, line_number, file_extension, error): """Checks rules from the 'C++ style rules' section of cppguide.html. Most of these rules are hard to test (naming, comment style), but we do what we can. In particular we check for 4-space indents, line lengths, tab usage, spaces inside code, etc. Args: filename: The name of the current file. clean_lines: A CleansedLines instance containing the file. line_number: The number of the line to check. file_extension: The extension (without the dot) of the filename. error: The function to call with any errors found. """ raw_lines = clean_lines.raw_lines line = raw_lines[line_number] if line.find('\t') != -1: error(filename, line_number, 'whitespace/tab', 1, 'Tab found; better to use spaces') # One or three blank spaces at the beginning of the line is weird; it's # hard to reconcile that with 4-space indents. # NOTE: here are the conditions rob pike used for his tests. Mine aren't # as sophisticated, but it may be worth becoming so: RLENGTH==initial_spaces # if(RLENGTH > 20) complain = 0; # if(match($0, " +(error|private|public|protected):")) complain = 0; # if(match(prev, "&& *$")) complain = 0; # if(match(prev, "\\|\\| *$")) complain = 0; # if(match(prev, "[\",=><] *$")) complain = 0; # if(match($0, " <<")) complain = 0; # if(match(prev, " +for \\(")) complain = 0; # if(prevodd && match(prevprev, " +for \\(")) complain = 0; initial_spaces = 0 cleansed_line = clean_lines.elided[line_number] while initial_spaces < len(line) and line[initial_spaces] == ' ': initial_spaces += 1 if line and line[-1].isspace(): error(filename, line_number, 'whitespace/end_of_line', 4, 'Line ends in whitespace. Consider deleting these extra spaces.') # There are certain situations we allow one space, notably for labels elif ((initial_spaces == 1 or initial_spaces == 3) and not match(r'\s*\w+\s*:\s*$', cleansed_line)): error(filename, line_number, 'whitespace/indent', 3, 'Weird number of spaces at line-start. ' 'Are you using at least 2-space indent?') # Labels should always be indented at least one space. elif not initial_spaces and line[:2] != '//': label_match = match(r'(?P