django1/django/utils/inspect.py

70 lines
1.8 KiB
Python

import functools
import inspect
@functools.lru_cache(maxsize=512)
def _get_signature(func):
return inspect.signature(func)
def get_func_args(func):
sig = _get_signature(func)
return [
arg_name for arg_name, param in sig.parameters.items()
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.
"""
sig = _get_signature(func)
args = []
for arg_name, param in sig.parameters.items():
name = arg_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 any(
p for p in _get_signature(func).parameters.values()
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_signature(func).parameters.values()
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_signature(meth).parameters.values()
if p.kind == p.POSITIONAL_OR_KEYWORD
])
return count == 0 if inspect.ismethod(meth) else count == 1
def func_supports_parameter(func, parameter):
return parameter in _get_signature(func).parameters