From 23a848c3141ad2ba1e7bb62708f5ed72ef81c98a Mon Sep 17 00:00:00 2001 From: dirkf Date: Sat, 1 Nov 2025 20:24:43 +0000 Subject: [utils] Add `partial_application` decorator function Thx: yt-dlp/yt-dlp#10653 --- youtube_dl/utils.py | 33 +++++++++++++++++++++++++++++++++ 1 file changed, 33 insertions(+) (limited to 'youtube_dl/utils.py') diff --git a/youtube_dl/utils.py b/youtube_dl/utils.py index 437257f5b..f2c02829b 100644 --- a/youtube_dl/utils.py +++ b/youtube_dl/utils.py @@ -1861,6 +1861,39 @@ def write_json_file(obj, fn): raise +class partial_application(object): + """Allow a function to use pre-set argument values""" + + # see _try_bind_args() + try: + inspect.signature + + @staticmethod + def required_args(fn): + return [ + param.name for param in inspect.signature(fn).parameters.values() + if (param.kind in (inspect.Parameter.POSITIONAL_ONLY, inspect.Parameter.POSITIONAL_OR_KEYWORD) + and param.default is inspect.Parameter.empty)] + + except AttributeError: + + # Py < 3.3 + @staticmethod + def required_args(fn): + fn_args = inspect.getargspec(fn) + n_defaults = len(fn_args.defaults or []) + return (fn_args.args or [])[:-n_defaults if n_defaults > 0 else None] + + def __new__(cls, func): + @functools.wraps(func) + def wrapped(*args, **kwargs): + if set(cls.required_args(func)[len(args):]).difference(kwargs): + return functools.partial(func, *args, **kwargs) + return func(*args, **kwargs) + + return wrapped + + if sys.version_info >= (2, 7): def find_xpath_attr(node, xpath, key, val=None): """ Find the xpath xpath[@key=val] """ -- cgit v1.2.3