django1/django/utils/inspect.py

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import functools
import inspect
@functools.lru_cache(maxsize=512)
def _get_func_parameters(func, remove_first):
parameters = tuple(inspect.signature(func).parameters.values())
if remove_first:
parameters = parameters[1:]
return parameters
def _get_callable_parameters(meth_or_func):
is_method = inspect.ismethod(meth_or_func)
func = meth_or_func.__func__ if is_method else meth_or_func
return _get_func_parameters(func, remove_first=is_method)
def get_func_args(func):
params = _get_callable_parameters(func)
return [
param.name for param in params
if param.kind == inspect.Parameter.POSITIONAL_OR_KEYWORD
]
def get_func_full_args(func):
"""
Return a list of (argument name, default value) tuples. If the argument
does not have a default value, omit it in the tuple. Arguments such as
*args and **kwargs are also included.
"""
params = _get_callable_parameters(func)
args = []
for param in params:
name = param.name
# Ignore 'self'
if name == 'self':
continue
if param.kind == inspect.Parameter.VAR_POSITIONAL:
name = '*' + name
elif param.kind == inspect.Parameter.VAR_KEYWORD:
name = '**' + name
if param.default != inspect.Parameter.empty:
args.append((name, param.default))
else:
args.append((name,))
return args
def func_accepts_kwargs(func):
"""Return True if function 'func' accepts keyword arguments **kwargs."""
return any(
p for p in _get_callable_parameters(func)
if p.kind == p.VAR_KEYWORD
)
def func_accepts_var_args(func):
"""
Return True if function 'func' accepts positional arguments *args.
"""
return any(
p for p in _get_callable_parameters(func)
if p.kind == p.VAR_POSITIONAL
)
def method_has_no_args(meth):
"""Return True if a method only accepts 'self'."""
count = len([
p for p in _get_callable_parameters(meth)
if p.kind == p.POSITIONAL_OR_KEYWORD
])
return count == 0 if inspect.ismethod(meth) else count == 1
def func_supports_parameter(func, name):
return any(param.name == name for param in _get_callable_parameters(func))