def CheckLanguage()

in cpplint.py [0:0]


def CheckLanguage(filename, clean_lines, linenum, file_extension,
                  include_state, nesting_state, error):
    """Checks rules from the 'C++ language rules' section of cppguide.html.

  Some of these rules are hard to test (function overloading, using
  uint32 inappropriately), but we do the best we can.

  Args:
    filename: The name of the current file.
    clean_lines: A CleansedLines instance containing the file.
    linenum: The number of the line to check.
    file_extension: The extension (without the dot) of the filename.
    include_state: An _IncludeState instance in which the headers are inserted.
    nesting_state: A NestingState instance which maintains information about
                   the current stack of nested blocks being parsed.
    error: The function to call with any errors found.
  """
    # If the line is empty or consists of entirely a comment, no need to
    # check it.
    line = clean_lines.elided[linenum]
    if not line:
        return

    match = _RE_PATTERN_INCLUDE.search(line)
    if match:
        CheckIncludeLine(filename, clean_lines, linenum, include_state, error)
        return

    # Reset include state across preprocessor directives.  This is meant
    # to silence warnings for conditional includes.
    match = Match(r'^\s*#\s*(if|ifdef|ifndef|elif|else|endif)\b', line)
    if match:
        include_state.ResetSection(match.group(1))

    # Make Windows paths like Unix.
    fullname = os.path.abspath(filename).replace('\\', '/')

    # Perform other checks now that we are sure that this is not an include line
    CheckCasts(filename, clean_lines, linenum, error)
    CheckGlobalStatic(filename, clean_lines, linenum, error)
    CheckPrintf(filename, clean_lines, linenum, error)

    if IsHeaderExtension(file_extension):
        # TODO(unknown): check that 1-arg constructors are explicit.
        #                How to tell it's a constructor?
        #                (handled in CheckForNonStandardConstructs for now)
        # TODO(unknown): check that classes declare or disable copy/assign
        #                (level 1 error)
        pass

    # Check if people are using the verboten C basic types.  The only exception
    # we regularly allow is "unsigned short port" for port.
    if Search(r'\bshort port\b', line):
        if not Search(r'\bunsigned short port\b', line):
            error(filename, linenum, 'runtime/int', 4,
                  'Use "unsigned short" for ports, not "short"')
    else:
        match = Search(r'\b(short|long(?! +double)|long long)\b', line)
        if match:
            error(filename, linenum, 'runtime/int', 4,
                  'Use int16/int64/etc, rather than the C type %s' % match.group(1))

    # Check if some verboten operator overloading is going on
    # TODO(unknown): catch out-of-line unary operator&:
    #   class X {};
    #   int operator&(const X& x) { return 42; }  // unary operator&
    # The trick is it's hard to tell apart from binary operator&:
    #   class Y { int operator&(const Y& x) { return 23; } }; // binary operator&
    if Search(r'\boperator\s*&\s*\(\s*\)', line):
        error(filename, linenum, 'runtime/operator', 4,
              'Unary operator& is dangerous.  Do not use it.')

    # Check for suspicious usage of "if" like
    # } if (a == b) {
    if Search(r'\}\s*if\s*\(', line):
        error(filename, linenum, 'readability/braces', 4,
              'Did you mean "else if"? If not, start a new line for "if".')

    # Check for potential format string bugs like printf(foo).
    # We constrain the pattern not to pick things like DocidForPrintf(foo).
    # Not perfect but it can catch printf(foo.c_str()) and printf(foo->c_str())
    # TODO(unknown): Catch the following case. Need to change the calling
    # convention of the whole function to process multiple line to handle it.
    #   printf(
    #       boy_this_is_a_really_long_variable_that_cannot_fit_on_the_prev_line);
    printf_args = _GetTextInside(line, r'(?i)\b(string)?printf\s*\(')
    if printf_args:
        match = Match(r'([\w.\->()]+)$', printf_args)
        if match and match.group(1) != '__VA_ARGS__':
            function_name = re.search(r'\b((?:string)?printf)\s*\(',
                                      line, re.I).group(1)
            error(filename, linenum, 'runtime/printf', 4,
                  'Potential format string bug. Do %s("%%s", %s) instead.'
                  % (function_name, match.group(1)))

    # Check for potential memset bugs like memset(buf, sizeof(buf), 0).
    match = Search(r'memset\s*\(([^,]*),\s*([^,]*),\s*0\s*\)', line)
    if match and not Match(r"^''|-?[0-9]+|0x[0-9A-Fa-f]$", match.group(2)):
        error(filename, linenum, 'runtime/memset', 4,
              'Did you mean "memset(%s, 0, %s)"?'
              % (match.group(1), match.group(2)))

    if Search(r'\busing namespace\b', line):
        error(filename, linenum, 'build/namespaces', 5,
              'Do not use namespace using-directives.  '
              'Use using-declarations instead.')

    # Detect variable-length arrays.
    match = Match(r'\s*(.+::)?(\w+) [a-z]\w*\[(.+)];', line)
    if (match and match.group(2) != 'return' and match.group(2) != 'delete' and
            match.group(3).find(']') == -1):
        # Split the size using space and arithmetic operators as delimiters.
        # If any of the resulting tokens are not compile time constants then
        # report the error.
        tokens = re.split(r'\s|\+|\-|\*|\/|<<|>>]', match.group(3))
        is_const = True
        skip_next = False
        for tok in tokens:
            if skip_next:
                skip_next = False
                continue

            if Search(r'sizeof\(.+\)', tok): continue
            if Search(r'arraysize\(\w+\)', tok): continue

            tok = tok.lstrip('(')
            tok = tok.rstrip(')')
            if not tok: continue
            if Match(r'\d+', tok): continue
            if Match(r'0[xX][0-9a-fA-F]+', tok): continue
            if Match(r'k[A-Z0-9]\w*', tok): continue
            if Match(r'(.+::)?k[A-Z0-9]\w*', tok): continue
            if Match(r'(.+::)?[A-Z][A-Z0-9_]*', tok): continue
            # A catch all for tricky sizeof cases, including 'sizeof expression',
            # 'sizeof(*type)', 'sizeof(const type)', 'sizeof(struct StructName)'
            # requires skipping the next token because we split on ' ' and '*'.
            if tok.startswith('sizeof'):
                skip_next = True
                continue
            is_const = False
            break
        if not is_const:
            error(filename, linenum, 'runtime/arrays', 1,
                  'Do not use variable-length arrays.  Use an appropriately named '
                  "('k' followed by CamelCase) compile-time constant for the size.")

    # Check for use of unnamed namespaces in header files.  Registration
    # macros are typically OK, so we allow use of "namespace {" on lines
    # that end with backslashes.
    if (IsHeaderExtension(file_extension)
            and Search(r'\bnamespace\s*{', line)
            and line[-1] != '\\'):
        error(filename, linenum, 'build/namespaces', 4,
              'Do not use unnamed namespaces in header files.  See '
              'https://google-styleguide.googlecode.com/svn/trunk/cppguide.xml#Namespaces'
              ' for more information.')