diff options
Diffstat (limited to 'distutils2/_backport/functools.py')
| -rw-r--r-- | distutils2/_backport/functools.py | 56 |
1 files changed, 56 insertions, 0 deletions
diff --git a/distutils2/_backport/functools.py b/distutils2/_backport/functools.py new file mode 100644 index 0000000..6d83cbd --- /dev/null +++ b/distutils2/_backport/functools.py @@ -0,0 +1,56 @@ +"""functools.py - Tools for working with functions and callable objects +Copied from: +https://github.com/dln/pycassa/commit/90736f8146c1cac8287f66e8c8b64cb80e011513#diff-1 + +""" + +try: + from _functools import partial +except: + class partial(object): + "A simple replacement of functools.partial" + def __init__(self, func, *args, **kw): + self.func = func + self.args = args + self.keywords = kw + def __call__(self, *otherargs, **otherkw): + kw = self.keywords.copy() + kw.update(otherkw) + return self.func(*(self.args + otherargs), **kw) + +# update_wrapper() and wraps() are tools to help write +# wrapper functions that can handle naive introspection + +WRAPPER_ASSIGNMENTS = ('__module__', '__name__', '__doc__') +WRAPPER_UPDATES = ('__dict__',) +def update_wrapper(wrapper, wrapped, assigned=WRAPPER_ASSIGNMENTS, + updated=WRAPPER_UPDATES): + """Update a wrapper function to look like the wrapped function + + wrapper is the function to be updated + wrapped is the original function + assigned is a tuple naming the attributes assigned directly + from the wrapped function to the wrapper function (defaults to + functools.WRAPPER_ASSIGNMENTS) + updated is a tuple naming the attributes of the wrapper that + are updated with the corresponding attribute from the wrapped + function (defaults to functools.WRAPPER_UPDATES) + """ + for attr in assigned: + setattr(wrapper, attr, getattr(wrapped, attr)) + for attr in updated: + getattr(wrapper, attr).update(getattr(wrapped, attr, {})) + # Return the wrapper so this can be used as a decorator via partial() + return wrapper + +def wraps(wrapped, assigned=WRAPPER_ASSIGNMENTS, updated=WRAPPER_UPDATES): + """Decorator factory to apply update_wrapper() to a wrapper function + + Returns a decorator that invokes update_wrapper() with the decorated + function as the wrapper argument and the arguments to wraps() as the + remaining arguments. Default arguments are as for update_wrapper(). + This is a convenience function to simplify applying partial() to + update_wrapper(). + """ + return partial(update_wrapper, wrapped=wrapped, + assigned=assigned, updated=updated) |
