Mercurial > repos > guerler > springsuite
diff planemo/lib/python3.7/site-packages/future/builtins/newsuper.py @ 0:d30785e31577 draft
"planemo upload commit 6eee67778febed82ddd413c3ca40b3183a3898f1"
author | guerler |
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date | Fri, 31 Jul 2020 00:18:57 -0400 |
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--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/planemo/lib/python3.7/site-packages/future/builtins/newsuper.py Fri Jul 31 00:18:57 2020 -0400 @@ -0,0 +1,114 @@ +''' +This module provides a newsuper() function in Python 2 that mimics the +behaviour of super() in Python 3. It is designed to be used as follows: + + from __future__ import division, absolute_import, print_function + from future.builtins import super + +And then, for example: + + class VerboseList(list): + def append(self, item): + print('Adding an item') + super().append(item) # new simpler super() function + +Importing this module on Python 3 has no effect. + +This is based on (i.e. almost identical to) Ryan Kelly's magicsuper +module here: + + https://github.com/rfk/magicsuper.git + +Excerpts from Ryan's docstring: + + "Of course, you can still explicitly pass in the arguments if you want + to do something strange. Sometimes you really do want that, e.g. to + skip over some classes in the method resolution order. + + "How does it work? By inspecting the calling frame to determine the + function object being executed and the object on which it's being + called, and then walking the object's __mro__ chain to find out where + that function was defined. Yuck, but it seems to work..." +''' + +from __future__ import absolute_import +import sys +from types import FunctionType + +from future.utils import PY3, PY26 + + +_builtin_super = super + +_SENTINEL = object() + +def newsuper(typ=_SENTINEL, type_or_obj=_SENTINEL, framedepth=1): + '''Like builtin super(), but capable of magic. + + This acts just like the builtin super() function, but if called + without any arguments it attempts to infer them at runtime. + ''' + # Infer the correct call if used without arguments. + if typ is _SENTINEL: + # We'll need to do some frame hacking. + f = sys._getframe(framedepth) + + try: + # Get the function's first positional argument. + type_or_obj = f.f_locals[f.f_code.co_varnames[0]] + except (IndexError, KeyError,): + raise RuntimeError('super() used in a function with no args') + + try: + # Get the MRO so we can crawl it. + mro = type_or_obj.__mro__ + except (AttributeError, RuntimeError): # see issue #160 + try: + mro = type_or_obj.__class__.__mro__ + except AttributeError: + raise RuntimeError('super() used with a non-newstyle class') + + # A ``for...else`` block? Yes! It's odd, but useful. + # If unfamiliar with for...else, see: + # + # http://psung.blogspot.com/2007/12/for-else-in-python.html + for typ in mro: + # Find the class that owns the currently-executing method. + for meth in typ.__dict__.values(): + # Drill down through any wrappers to the underlying func. + # This handles e.g. classmethod() and staticmethod(). + try: + while not isinstance(meth,FunctionType): + if isinstance(meth, property): + # Calling __get__ on the property will invoke + # user code which might throw exceptions or have + # side effects + meth = meth.fget + else: + try: + meth = meth.__func__ + except AttributeError: + meth = meth.__get__(type_or_obj, typ) + except (AttributeError, TypeError): + continue + if meth.func_code is f.f_code: + break # Aha! Found you. + else: + continue # Not found! Move onto the next class in MRO. + break # Found! Break out of the search loop. + else: + raise RuntimeError('super() called outside a method') + + # Dispatch to builtin super(). + if type_or_obj is not _SENTINEL: + return _builtin_super(typ, type_or_obj) + return _builtin_super(typ) + + +def superm(*args, **kwds): + f = sys._getframe(1) + nm = f.f_code.co_name + return getattr(newsuper(framedepth=2),nm)(*args, **kwds) + + +__all__ = ['newsuper']