in cpplint.py [0:0]
def CheckForNonStandardConstructs(filename, clean_lines, linenum,
nesting_state, error):
r"""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 <? operators, and their >?= and <?= cousins.
Additionally, check for constructor/destructor style violations and reference
members, as it is very convenient to do so while checking for
gcc-2 compliance.
Args:
filename: The name of the current file.
clean_lines: A CleansedLines instance containing the file.
linenum: The number of the line to check.
nesting_state: A NestingState instance which maintains information about
the current stack of nested blocks being parsed.
error: A callable to which errors are reported, which takes 4 arguments:
filename, line number, error level, and message
"""
# Remove comments from the line, but leave in strings for now.
line = clean_lines.lines[linenum]
if Search(r'printf\s*\(.*".*%[-+ ]?\d*q', line):
error(filename, linenum, 'runtime/printf_format', 3,
'%q in format strings is deprecated. Use %ll instead.')
if Search(r'printf\s*\(.*".*%\d+\$', line):
error(filename, linenum, 'runtime/printf_format', 2,
'%N$ formats are unconventional. Try rewriting to avoid them.')
# Remove escaped backslashes before looking for undefined escapes.
line = line.replace('\\\\', '')
if Search(r'("|\').*\\(%|\[|\(|{)', line):
error(filename, linenum, 'build/printf_format', 3,
'%, [, (, and { are undefined character escapes. Unescape them.')
# For the rest, work with both comments and strings removed.
line = clean_lines.elided[linenum]
if Search(r'\b(const|volatile|void|char|short|int|long'
r'|float|double|signed|unsigned'
r'|schar|u?int8|u?int16|u?int32|u?int64)'
r'\s+(register|static|extern|typedef)\b',
line):
error(filename, linenum, 'build/storage_class', 5,
'Storage-class specifier (static, extern, typedef, etc) should be '
'at the beginning of the declaration.')
if Match(r'\s*#\s*endif\s*[^/\s]+', line):
error(filename, linenum, 'build/endif_comment', 5,
'Uncommented text after #endif is non-standard. Use a comment.')
if Match(r'\s*class\s+(\w+\s*::\s*)+\w+\s*;', line):
error(filename, linenum, 'build/forward_decl', 5,
'Inner-style forward declarations are invalid. Remove this line.')
if Search(r'(\w+|[+-]?\d+(\.\d*)?)\s*(<|>)\?=?\s*(\w+|[+-]?\d+)(\.\d*)?',
line):
error(filename, linenum, 'build/deprecated', 3,
'>? and <? (max and min) operators are non-standard and deprecated.')
if Search(r'^\s*const\s*string\s*&\s*\w+\s*;', line):
# TODO(unknown): Could it be expanded safely to arbitrary references,
# without triggering too many false positives? The first
# attempt triggered 5 warnings for mostly benign code in the regtest, hence
# the restriction.
# Here's the original regexp, for the reference:
# type_name = r'\w+((\s*::\s*\w+)|(\s*<\s*\w+?\s*>))?'
# r'\s*const\s*' + type_name + '\s*&\s*\w+\s*;'
error(filename, linenum, 'runtime/member_string_references', 2,
'const string& members are dangerous. It is much better to use '
'alternatives, such as pointers or simple constants.')
# Everything else in this function operates on class declarations.
# Return early if the top of the nesting stack is not a class, or if
# the class head is not completed yet.
classinfo = nesting_state.InnermostClass()
if not classinfo or not classinfo.seen_open_brace:
return
# 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.
explicit_constructor_match = Match(
r'\s+(?:(?:inline|constexpr)\s+)*(explicit\s+)?'
r'(?:(?:inline|constexpr)\s+)*%s\s*'
r'\(((?:[^()]|\([^()]*\))*)\)'
% re.escape(base_classname),
line)
if explicit_constructor_match:
is_marked_explicit = explicit_constructor_match.group(1)
if not explicit_constructor_match.group(2):
constructor_args = []
else:
constructor_args = explicit_constructor_match.group(2).split(',')
# collapse arguments so that commas in template parameter lists and function
# argument parameter lists don't split arguments in two
i = 0
while i < len(constructor_args):
constructor_arg = constructor_args[i]
while (constructor_arg.count('<') > constructor_arg.count('>') or
constructor_arg.count('(') > constructor_arg.count(')')):
constructor_arg += ',' + constructor_args[i + 1]
del constructor_args[i + 1]
constructor_args[i] = constructor_arg
i += 1
defaulted_args = [arg for arg in constructor_args if '=' in arg]
noarg_constructor = (not constructor_args or # empty arg list
# 'void' arg specifier
(len(constructor_args) == 1 and
constructor_args[0].strip() == 'void'))
onearg_constructor = ((len(constructor_args) == 1 and # exactly one arg
not noarg_constructor) or
# all but at most one arg defaulted
(len(constructor_args) >= 1 and
not noarg_constructor and
len(defaulted_args) >= len(constructor_args) - 1))
initializer_list_constructor = bool(
onearg_constructor and
Search(r'\bstd\s*::\s*initializer_list\b', constructor_args[0]))
copy_constructor = bool(
onearg_constructor and
Match(r'(const\s+)?%s(\s*<[^>]*>)?(\s+const)?\s*(?:<\w+>\s*)?&'
% re.escape(base_classname), constructor_args[0].strip()))
if (not is_marked_explicit and
onearg_constructor and
not initializer_list_constructor and
not copy_constructor):
if defaulted_args:
error(filename, linenum, 'runtime/explicit', 5,
'Constructors callable with one argument '
'should be marked explicit.')
else:
error(filename, linenum, 'runtime/explicit', 5,
'Single-parameter constructors should be marked explicit.')
elif is_marked_explicit and not onearg_constructor:
if noarg_constructor:
error(filename, linenum, 'runtime/explicit', 5,
'Zero-parameter constructors should not be marked explicit.')