diff -r 000000000000 -r 4f2f89ce4247 WebKitTools/Scripts/webkitpy/style/checkers/cpp.py --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/WebKitTools/Scripts/webkitpy/style/checkers/cpp.py Fri Sep 17 09:02:29 2010 +0300 @@ -0,0 +1,3005 @@ +#!/usr/bin/python +# -*- coding: utf-8 -*- +# +# Copyright (C) 2009 Google Inc. All rights reserved. +# Copyright (C) 2009 Torch Mobile Inc. +# Copyright (C) 2009 Apple Inc. All rights reserved. +# Copyright (C) 2010 Chris Jerdonek (cjerdonek@webkit.org) +# +# 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 + +"""Support for check-webkit-style.""" + +import codecs +import math # for log +import os +import os.path +import re +import sre_compile +import string +import sys +import unicodedata + + +# 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 +_MOC_HEADER = 3 + + +# The regexp compilation caching is inlined in all regexp functions for +# performance reasons; factoring it out into a separate function turns out +# to be noticeably expensive. +_regexp_compile_cache = {} + + +def match(pattern, s): + """Matches the string with 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].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) + + +def sub(pattern, replacement, s): + """Substitutes occurrences of a 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].sub(replacement, s) + + +def subn(pattern, replacement, s): + """Substitutes occurrences of a 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].subn(replacement, s) + + +def up_to_unmatched_closing_paren(s): + """Splits a string into two parts up to first unmatched ')'. + + Args: + s: a string which is a substring of line after '(' + (e.g., "a == (b + c))"). + + Returns: + A pair of strings (prefix before first unmatched ')', + remainder of s after first unmatched ')'), e.g., + up_to_unmatched_closing_paren("a == (b + c)) { ") + returns "a == (b + c)", " {". + Returns None, None if there is no unmatched ')' + + """ + i = 1 + for pos, c in enumerate(s): + if c == '(': + i += 1 + elif c == ')': + i -= 1 + if i == 0: + return s[:pos], s[pos + 1:] + return None, None + +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', + _MOC_HEADER: 'moc file', + } + _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.' + if header_type == _MOC_HEADER: + return '' + + 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 _FunctionState(object): + """Tracks current function name and the number of lines in its body. + + Attributes: + min_confidence: The minimum confidence level to use while checking style. + + """ + + _NORMAL_TRIGGER = 250 # for --v=0, 500 for --v=1, etc. + _TEST_TRIGGER = 400 # about 50% more than _NORMAL_TRIGGER. + + def __init__(self, min_confidence): + self.min_confidence = min_confidence + self.current_function = '' + self.in_a_function = False + self.lines_in_function = 0 + + 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, line_number): + """Report if too many lines in function body. + + Args: + error: The function to call with any errors found. + 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 ** self.min_confidence + + 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(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 + + +def is_c_or_objective_c(file_extension): + """Return whether the file extension corresponds to C or Objective-C. + + Args: + file_extension: The file extension without the leading dot. + + """ + return file_extension in ['c', 'm'] + + +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') + + +# 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(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(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(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', lines[line], re.I): + break + else: # means no copyright line was found + error(0, 'legal/copyright', 5, + 'No copyright message found. ' + 'You should have a line: "Copyright [year] "') + + +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. + + """ + + # Restores original filename in case that style checker is invoked from Emacs's + # flymake. + filename = re.sub(r'_flymake\.h$', '.h', filename) + + return sub(r'[-.\s]', '_', os.path.basename(filename)) + + +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 + 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] + if define and ifndef: + break + + if not ifndef or not define or ifndef != define: + error(0, 'build/header_guard', 5, + 'No #ifndef header guard found, suggested CPP variable is: %s' % + cppvar) + return + + # The guard should be File_h. + if ifndef != cppvar: + error(ifndef_line_number, 'build/header_guard', 5, + '#ifndef header guard has wrong style, please use: %s' % cppvar) + + +def check_for_unicode_replacement_characters(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: + 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(line_number, 'readability/utf8', 5, + 'Line contains invalid UTF-8 (or Unicode replacement character).') + + +def check_for_new_line_at_eof(lines, error): + """Logs an error if there is no newline char at the end of the file. + + Args: + 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(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(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: + 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(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(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(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: + 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(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(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: + 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(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, error): + """Checks that all classes have been completely parsed. + + Call this when all lines in a file have been processed. + Args: + 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 + # cpp_style_unittest.py for an example of this. + error(self.classinfo_stack[0].line_number, 'build/class', 5, + 'Failed to find complete declaration of class %s' % + self.classinfo_stack[0].name) + + +class _FileState(object): + def __init__(self): + self._did_inside_namespace_indent_warning = False + + def set_did_inside_namespace_indent_warning(self): + self._did_inside_namespace_indent_warning = True + + def did_inside_namespace_indent_warning(self): + return self._did_inside_namespace_indent_warning + +def check_for_non_standard_constructs(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$d" is non-standard in printf-type functions. + - "\%" is an undefined character escape sequence. + - text after #endif is not allowed. + - invalid inner-style forward declaration. + - >? and ?= and )\?=?\s*(\w+|[+-]?\d+)(\.\d*)?', line): + error(line_number, 'build/deprecated', 3, + '>? and ,:]*>\s*)?(class|struct)\s+(\w+(::\w+)*)', line) + if class_decl_match: + classinfo_stack.append(_ClassInfo(class_decl_match.group(3), line_number)) + + # Everything else in this function uses the top of the stack if it's + # not empty. + if not classinfo_stack: + return + + classinfo = classinfo_stack[-1] + + # If the opening brace hasn't been seen look for it and also + # parent class declarations. + if not classinfo.seen_open_brace: + # If the line has a ';' in it, assume it's a forward declaration or + # a single-line class declaration, which we won't process. + if line.find(';') != -1: + classinfo_stack.pop() + return + classinfo.seen_open_brace = (line.find('{') != -1) + # Look for a bare ':' + if search('(^|[^:]):($|[^:])', 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*$|:)', + previous_line) + or match(r' {4}:', previous_line)) + + if not exception: + error(line_number, 'whitespace/blank_line', 2, + 'Blank line at the start of a code block. Is this needed?') + # This doesn't ignore whitespace at the end of a namespace block + # because that is too hard without pairing open/close braces; + # however, a special exception is made for namespace closing + # brackets which have a comment containing "namespace". + # + # Also, ignore blank lines at the end of a block in a long if-else + # chain, like this: + # if (condition1) { + # // Something followed by a blank line + # + # } else if (condition2) { + # // Something else + # } + if line_number + 1 < clean_lines.num_lines(): + next_line = raw[line_number + 1] + if (next_line + and match(r'\s*}', next_line) + and next_line.find('namespace') == -1 + and next_line.find('} else ') == -1): + error(line_number, 'whitespace/blank_line', 3, + 'Blank line at the end of a code block. Is this needed?') + + # Next, we complain if there's a comment too near the text + comment_position = line.find('//') + if comment_position != -1: + # Check if the // may be in quotes. If so, ignore it + # Comparisons made explicit for clarity -- pylint: disable-msg=C6403 + if (line.count('"', 0, comment_position) - line.count('\\"', 0, comment_position)) % 2 == 0: # not in quotes + # Allow one space before end of line comment. + if (not match(r'^\s*$', line[:comment_position]) + and (comment_position >= 1 + and ((line[comment_position - 1] not in string.whitespace) + or (comment_position >= 2 + and line[comment_position - 2] in string.whitespace)))): + error(line_number, 'whitespace/comments', 5, + 'One space before end of line 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(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 = sub(r'operator(==|!=|<|<<|<=|>=|>>|>)\(', 'operator\(', line) + # Don't try to do spacing checks for #include or #import statements at + # minimum because it messes up checks for spacing around / + if match(r'\s*#\s*(?:include|import)', line): + return + if search(r'[\w.]=[\w.]', line): + error(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(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(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(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(?Pif|for|foreach|while|switch)\s*\((?P.*)$', line) + if matched: + statement = matched.group('statement') + condition, rest = up_to_unmatched_closing_paren(matched.group('remainder')) + if condition is not None: + condition_match = search(r'(?P[ ]*)(?P.).*[^ ]+(?P[ ]*)', condition) + if condition_match: + n_leading = len(condition_match.group('leading')) + n_trailing = len(condition_match.group('trailing')) + if n_leading != 0: + for_exception = statement == 'for' and condition.startswith(' ;') + if not for_exception: + error(line_number, 'whitespace/parens', 5, + 'Extra space after ( in %s' % statement) + if n_trailing != 0: + for_exception = statement == 'for' and condition.endswith('; ') + if not for_exception: + error(line_number, 'whitespace/parens', 5, + 'Extra space before ) in %s' % statement) + + # Do not check for more than one command in macros + in_macro = match(r'\s*#define', line) + if not in_macro and not match(r'((\s*{\s*}?)|(\s*;?))\s*\\?$', rest): + error(line_number, 'whitespace/parens', 4, + 'More than one command on the same line in %s' % statement) + + # You should always have a space after a comma (either as fn arg or operator) + if search(r',[^\s]', line): + error(line_number, 'whitespace/comma', 3, + 'Missing space after ,') + + matched = search(r'^\s*(?P[a-zA-Z0-9_\*&]+)\s\s+(?P[a-zA-Z0-9_\*&]+)', line) + if matched: + error(line_number, 'whitespace/declaration', 3, + 'Extra space between %s and %s' % (matched.group('token1'), matched.group('token2'))) + + if file_extension == 'cpp': + # C++ should have the & or * beside the type not the variable name. + matched = match(r'\s*\w+(?\*|\&)\w+', line) + if matched: + error(line_number, 'whitespace/declaration', 3, + 'Declaration has space between type name and %s in %s' % (matched.group('pointer_operator'), matched.group(0).strip())) + + elif file_extension == 'c': + # C Pointer declaration should have the * beside the variable not the type name. + matched = search(r'^\s*\w+\*\s+\w+', line) + if matched: + error(line_number, 'whitespace/declaration', 3, + 'Declaration has space between * and variable name in %s' % matched.group(0).strip()) + + # Next we will look for issues with function calls. + check_spacing_for_function_call(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(line_number, 'whitespace/braces', 5, + 'Missing space before {') + + # Make sure '} else {' has spaces. + if search(r'}else', line): + error(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(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*$', line): + error(line_number, 'whitespace/semicolon', 5, + 'Semicolon defining empty statement. Use { } instead.') + elif search(r'^\s*;\s*$', line): + error(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(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*$', line) + and line.count('(') == line.count(')') + # Allow do {} while(); + and not search(r'}\s*while', line)): + error(line_number, 'whitespace/semicolon', 5, + 'Semicolon defining empty statement for this loop. Use { } instead.') + + +def get_previous_non_blank_line(clean_lines, line_number): + """Return the most recent non-blank line and its line number. + + Args: + clean_lines: A CleansedLines instance containing the file contents. + line_number: The number of the line to check. + + Returns: + A tuple with two elements. The first element is the contents of the last + non-blank line before the current line, or the empty string if this is the + first non-blank line. The second is the line number of that line, or -1 + if this is the first non-blank line. + """ + + previous_line_number = line_number - 1 + while previous_line_number >= 0: + previous_line = clean_lines.elided[previous_line_number] + if not is_blank_line(previous_line): # if not a blank line... + return (previous_line, previous_line_number) + previous_line_number -= 1 + return ('', -1) + + +def check_namespace_indentation(clean_lines, line_number, file_extension, file_state, error): + """Looks for indentation errors inside of namespaces. + + Args: + clean_lines: A CleansedLines instance containing the file. + line_number: The number of the line to check. + file_extension: The extension (dot not included) of the file. + file_state: A _FileState instance which maintains information about + the state of things in the file. + error: The function to call with any errors found. + """ + + line = clean_lines.elided[line_number] # Get rid of comments and strings. + + namespace_match = match(r'(?P\s*)namespace\s+\S+\s*{\s*$', line) + if not namespace_match: + return + + current_indentation_level = len(namespace_match.group('namespace_indentation')) + if current_indentation_level > 0: + # Don't warn about an indented namespace if we already warned about indented code. + if not file_state.did_inside_namespace_indent_warning(): + error(line_number, 'whitespace/indent', 4, + 'namespace should never be indented.') + return + looking_for_semicolon = False; + line_offset = 0 + in_preprocessor_directive = False; + for current_line in clean_lines.elided[line_number + 1:]: + line_offset += 1 + if not current_line.strip(): + continue + if not current_indentation_level: + if not (in_preprocessor_directive or looking_for_semicolon): + if not match(r'\S', current_line) and not file_state.did_inside_namespace_indent_warning(): + file_state.set_did_inside_namespace_indent_warning() + error(line_number + line_offset, 'whitespace/indent', 4, + 'Code inside a namespace should not be indented.') + if in_preprocessor_directive or (current_line.strip()[0] == '#'): # This takes care of preprocessor directive syntax. + in_preprocessor_directive = current_line[-1] == '\\' + else: + looking_for_semicolon = ((current_line.find(';') == -1) and (current_line.strip()[-1] != '}')) or (current_line[-1] == '\\') + else: + looking_for_semicolon = False; # If we have a brace we may not need a semicolon. + current_indentation_level += current_line.count('{') - current_line.count('}') + if current_indentation_level < 0: + break; + +def check_using_std(file_extension, clean_lines, line_number, error): + """Looks for 'using std::foo;' statements which should be replaced with 'using namespace std;'. + + Args: + file_extension: The extension of the current file, without the leading dot. + 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. + """ + + # This check doesn't apply to C or Objective-C implementation files. + if is_c_or_objective_c(file_extension): + return + + line = clean_lines.elided[line_number] # Get rid of comments and strings. + + using_std_match = match(r'\s*using\s+std::(?P\S+)\s*;\s*$', line) + if not using_std_match: + return + + method_name = using_std_match.group('method_name') + error(line_number, 'build/using_std', 4, + "Use 'using namespace std;' instead of 'using std::%s;'." % method_name) + + +def check_max_min_macros(file_extension, clean_lines, line_number, error): + """Looks use of MAX() and MIN() macros that should be replaced with std::max() and std::min(). + + Args: + file_extension: The extension of the current file, without the leading dot. + 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. + """ + + # This check doesn't apply to C or Objective-C implementation files. + if is_c_or_objective_c(file_extension): + return + + line = clean_lines.elided[line_number] # Get rid of comments and strings. + + max_min_macros_search = search(r'\b(?P(MAX|MIN))\s*\(', line) + if not max_min_macros_search: + return + + max_min_macro = max_min_macros_search.group('max_min_macro') + max_min_macro_lower = max_min_macro.lower() + error(line_number, 'runtime/max_min_macros', 4, + 'Use std::%s() or std::%s() instead of the %s() macro.' + % (max_min_macro_lower, max_min_macro_lower, max_min_macro)) + + +def check_switch_indentation(clean_lines, line_number, error): + """Looks for indentation errors inside of switch statements. + + Args: + 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*:([^:].*)?$', remaining_line): + if current_indentation != switch_indentation: + error(line_number + line_offset, 'whitespace/indent', 4, + 'A case label should not be indented, but line up with its switch statement.') + # Don't throw an error for multiple badly indented labels, + # one should be enough to figure out the problem. + break + # We ignore goto labels at the very beginning of a line. + elif match(r'\w+\s*:\s*$', 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(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(clean_lines, line_number, error): + """Looks for misplaced braces (e.g. at the end of line). + + Args: + 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. + + 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(line_number, 'whitespace/braces', 4, + 'This { should be at the end of the previous line') + elif (search(r'\)\s*(const\s*)?{\s*$', line) + and line.count('(') == line.count(')') + and not search(r'\b(if|for|foreach|while|switch)\b', line) + and not match(r'\s+[A-Z_][A-Z_0-9]+\b', line)): + error(line_number, 'whitespace/braces', 4, + 'Place brace on its own line for function definitions.') + + if (match(r'\s*}\s*(else\s*({\s*)?)?$', 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 previous_line.find('}') < 0 + and search(r'\b(if|for|foreach|while|else)\b', previous_line)): + error(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(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(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(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(line_number, 'readability/braces', 4, + "You don't need a ; after a }") + + +def check_exit_statement_simplifications(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: + 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(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(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(clean_lines, line_number, error): + """Checks the use of CHECK and EXPECT macros. + + Args: + 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(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(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(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(file_extension, clean_lines, line_number, error): + # This check doesn't apply to C or Objective-C implementation files. + if is_c_or_objective_c(file_extension): + return + + line = clean_lines.elided[line_number] + + # Don't warn about NULL usage in g_*(). See Bug 32858 and 39372. + if search(r'\bg(_[a-z]+)+\b', line): + return + + # Don't warn about NULL usage in gst_*_many(). See Bug 39740 + if search(r'\bgst_\w+_many\b', line): + return + + # Don't warn about NULL usage in g_str{join,concat}(). See Bug 34834 + if search(r'\bg_str(join|concat)\b', line): + return + + if search(r'\bNULL\b', line): + error(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(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(clean_lines, line_number, file_extension, file_state, 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: + 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. + file_state: A _FileState instance which maintains information about + the state of things in the file. + 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(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($0, " <<")) complain = 0; + # if(match(prev, " +for \\(")) complain = 0; + # if(prevodd && match(prevprev, " +for \\(")) complain = 0; + initial_spaces = 0 + cleansed_line = clean_lines.elided[line_number] + while initial_spaces < len(line) and line[initial_spaces] == ' ': + initial_spaces += 1 + if line and line[-1].isspace(): + error(line_number, 'whitespace/end_of_line', 4, + 'Line ends in whitespace. Consider deleting these extra spaces.') + # There are certain situations we allow one space, notably for labels + elif ((initial_spaces >= 1 and initial_spaces <= 3) + and not match(r'\s*\w+\s*:\s*$', cleansed_line)): + error(line_number, 'whitespace/indent', 3, + 'Weird number of spaces at line-start. ' + 'Are you using a 4-space indent?') + # Labels should always be indented at least one space. + elif not initial_spaces and line[:2] != '//': + label_match = match(r'(?P