"""Utilities for writing code that runs on Python 2 and 3""" import sys import types __author__ = "Benjamin Peterson " __version__ = "1.0.0" # True if we are running on Python 3. PY3 = sys.version_info[0] == 3 if PY3: string_types = str, integer_types = int, class_types = type, text_type = str binary_type = bytes MAXSIZE = sys.maxsize else: string_types = basestring, integer_types = (int, long) class_types = (type, types.ClassType) text_type = unicode binary_type = str MAXSIZE = sys.maxint def _add_doc(func, doc): """Add documentation to a function.""" func.__doc__ = doc def _import_module(name): """Import module, returning the module after the last dot.""" __import__(name) return sys.modules[name] class _LazyDescr(object): def __init__(self, name): self.name = name def __get__(self, obj, tp): result = self._resolve() setattr(obj, self.name, result) # This is a bit ugly, but it avoids running this again. delattr(tp, self.name) return result class MovedModule(_LazyDescr): def __init__(self, name, old, new=None): super(MovedModule, self).__init__(name) if PY3: if new is None: new = name self.mod = new else: self.mod = old def _resolve(self): return _import_module(self.mod) class MovedAttribute(_LazyDescr): def __init__(self, name, old_mod, new_mod, old_attr=None, new_attr=None): super(MovedAttribute, self).__init__(name) if PY3: if new_mod is None: new_mod = name self.mod = new_mod if new_attr is None: if old_attr is None: new_attr = name else: new_attr = old_attr self.attr = new_attr else: self.mod = old_mod if old_attr is None: old_attr = name self.attr = old_attr def _resolve(self): module = _import_module(self.mod) return getattr(module, self.attr) class _MovedItems(types.ModuleType): """Lazy loading of moved objects""" _moved_attributes = [ MovedAttribute("cStringIO", "cStringIO", "io", "StringIO"), MovedAttribute("reload_module", "__builtin__", "imp", "reload"), MovedAttribute("reduce", "__builtin__", "functools"), MovedAttribute("StringIO", "StringIO", "io"), MovedAttribute("xrange", "__builtin__", "builtins", "xrange", "range"), MovedModule("builtins", "__builtin__"), MovedModule("configparser", "ConfigParser"), MovedModule("copyreg", "copy_reg"), MovedModule("http_cookiejar", "cookielib", "http.cookiejar"), MovedModule("http_cookies", "Cookie", "http.cookies"), MovedModule("html_entities", "htmlentitydefs", "html.entities"), MovedModule("html_parser", "HTMLParser", "html.parser"), MovedModule("http_client", "httplib", "http.client"), MovedModule("BaseHTTPServer", "BaseHTTPServer", "http.server"), MovedModule("CGIHTTPServer", "CGIHTTPServer", "http.server"), MovedModule("SimpleHTTPServer", "SimpleHTTPServer", "http.server"), MovedModule("cPickle", "cPickle", "pickle"), MovedModule("queue", "Queue"), MovedModule("reprlib", "repr"), MovedModule("socketserver", "SocketServer"), MovedModule("tkinter", "Tkinter"), MovedModule("tkinter_dialog", "Dialog", "tkinter.dialog"), MovedModule("tkinter_filedialog", "FileDialog", "tkinter.filedialog"), MovedModule("tkinter_scrolledtext", "ScrolledText", "tkinter.scrolledtext"), MovedModule("tkinter_simpledialog", "SimpleDialog", "tkinter.simpledialog"), MovedModule("tkinter_tix", "Tix", "tkinter.tix"), MovedModule("tkinter_constants", "Tkconstants", "tkinter.constants"), MovedModule("tkinter_dnd", "Tkdnd", "tkinter.dnd"), MovedModule("tkinter_colorchooser", "tkColorChooser", "tkinter.colorchooser"), MovedModule("tkinter_commondialog", "tkCommonDialog", "tkinter.commondialog"), MovedModule("tkinter_tkfiledialog", "tkFileDialog", "tkinter.filedialog"), MovedModule("tkinter_font", "tkFont", "tkinter.font"), MovedModule("tkinter_messagebox", "tkMessageBox", "tkinter.messagebox"), MovedModule("tkinter_tksimpledialog", "tkSimpleDialog", "tkinter.simpledialog"), MovedModule("urllib_robotparser", "robotparser", "urllib.robotparser"), MovedModule("winreg", "_winreg"), ] for attr in _moved_attributes: setattr(_MovedItems, attr.name, attr) del attr moves = sys.modules["six.moves"] = _MovedItems("moves") def add_move(move): """Add an item to six.moves.""" setattr(_MovedItems, move.name, move) def remove_move(name): """Remove item from six.moves.""" try: delattr(_MovedItems, name) except AttributeError: try: del moves.__dict__[name] except KeyError: raise AttributeError("no such move, %r" % (name,)) if PY3: _meth_func = "__func__" _meth_self = "__self__" _func_code = "__code__" _func_defaults = "__defaults__" else: _meth_func = "im_func" _meth_self = "im_self" _func_code = "func_code" _func_defaults = "func_defaults" if PY3: def get_unbound_function(unbound): return unbound advance_iterator = next def callable(obj): return any("__call__" in klass.__dict__ for klass in type(obj).__mro__) else: def get_unbound_function(unbound): return unbound.im_func def advance_iterator(it): return it.next() callable = callable _add_doc(get_unbound_function, """Get the function out of a possibly unbound function""") def get_method_function(meth): """Get the underlying function of a bound method.""" return getattr(meth, _meth_func) def get_method_self(meth): """Get the self of a bound method.""" return getattr(meth, _meth_self) def get_function_code(func): """Get code object of a function.""" return getattr(func, _func_code) def get_function_defaults(func): """Get defaults of a function.""" return getattr(func, _func_defaults) if PY3: def b(s): return s.encode("latin-1") def u(s): return s import io StringIO = io.StringIO BytesIO = io.BytesIO else: def b(s): return s def u(s): return unicode(s, "unicode_escape") import StringIO StringIO = BytesIO = StringIO.StringIO _add_doc(b, """Byte literal""") _add_doc(u, """Text literal""") if PY3: exec_ = eval("exec") def reraise(tp, value, tb=None): if value.__traceback__ is not tb: raise value.with_traceback(tb) raise value print_ = eval("print") def with_metaclass(meta, base=object): ns = dict(base=base, meta=meta) exec_("""class NewBase(base, metaclass=meta): pass""", ns) return ns["NewBase"] else: def exec_(code, globs=None, locs=None): """Execute code in a namespace.""" if globs is None: frame = sys._getframe(1) globs = frame.f_globals if locs is None: locs = frame.f_locals del frame elif locs is None: locs = globs exec("""exec code in globs, locs""") exec_("""def reraise(tp, value, tb=None): raise tp, value, tb """) def print_(*args, **kwargs): """The new-style print function.""" fp = kwargs.pop("file", sys.stdout) if fp is None: return def write(data): if not isinstance(data, basestring): data = str(data) fp.write(data) want_unicode = False sep = kwargs.pop("sep", None) if sep is not None: if isinstance(sep, unicode): want_unicode = True elif not isinstance(sep, str): raise TypeError("sep must be None or a string") end = kwargs.pop("end", None) if end is not None: if isinstance(end, unicode): want_unicode = True elif not isinstance(end, str): raise TypeError("end must be None or a string") if kwargs: raise TypeError("invalid keyword arguments to print()") if not want_unicode: for arg in args: if isinstance(arg, unicode): want_unicode = True break if want_unicode: newline = unicode("\n") space = unicode(" ") else: newline = "\n" space = " " if sep is None: sep = space if end is None: end = newline for i, arg in enumerate(args): if i: write(sep) write(arg) write(end) def with_metaclass(meta, base=object): class NewBase(base): __metaclass__ = meta return NewBase _add_doc(reraise, """Reraise an exception.""") _add_doc(with_metaclass, """Create a base class with a metaclass""")