Function CheckCStyleCast

cpplint.py:6610–6663

Checks for a C-style cast by looking for the pattern. Args: filename: The name of the current file. clean_lines: A CleansedLines instance containing the file. linenum: The number of the line to check. cast_type: The string for the C++ cast to recommend. This is either

(filename, clean_lines, linenum, cast_type, pattern, error)

def CheckCStyleCast(filename, clean_lines, linenum, cast_type, pattern, error):
    """Checks for a C-style cast by looking for the pattern.

    Args:
      filename: The name of the current file.
      clean_lines: A CleansedLines instance containing the file.
      linenum: The number of the line to check.
      cast_type: The string for the C++ cast to recommend.  This is either
        reinterpret_cast, static_cast, or const_cast, depending.
      pattern: The regular expression used to find C-style casts.
      error: The function to call with any errors found.

    Returns:
      True if an error was emitted.
      False otherwise.
    """
    line = clean_lines.elided[linenum]
    match = re.search(pattern, line)
    if not match:
        return False

    # Exclude lines with keywords that tend to look like casts
    context = line[0 : match.start(1) - 1]
    if re.match(r".*\b(?:sizeof|alignof|alignas|[_A-Z][_A-Z0-9]*)\s*$", context):
        return False

    # Try expanding current context to see if we one level of
    # parentheses inside a macro.
    if linenum > 0:
        for i in range(linenum - 1, max(0, linenum - 5), -1):
            context = clean_lines.elided[i] + context
    if re.match(r".*\b[_A-Z][_A-Z0-9]*\s*\((?:\([^()]*\)|[^()])*$", context):
        return False

    # operator++(int) and operator--(int)
    if context.endswith((" operator++", " operator--", "::operator++", "::operator--")):
        return False

    # A single unnamed argument for a function tends to look like old style cast.
    # If we see those, don't issue warnings for deprecated casts.
    remainder = line[match.end(0) :]
    if re.match(r"^\s*(?:;|const\b|throw\b|final\b|override\b|[=>{),]|->)", remainder):
        return False

    # At this point, all that should be left is actual casts.
    error(
        filename,
        linenum,
        "readability/casting",
        4,
        f"Using C-style cast.  Use {cast_type}<{match.group(1)}>(...) instead",
    )

    return True


def ExpectingFunctionArgs(clean_lines, linenum):