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f9169ce6b4
Some objects (like test mocks) auto-generate new objects on attribute access, which can lead to an infinite loop in inspect.unwrap(). Ensuring references are retained to otherwise temporary objects and capping the size of the memo dict turns this case into a conventional exception instead.
3099 lines
113 KiB
Python
3099 lines
113 KiB
Python
"""Get useful information from live Python objects.
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This module encapsulates the interface provided by the internal special
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attributes (co_*, im_*, tb_*, etc.) in a friendlier fashion.
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It also provides some help for examining source code and class layout.
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Here are some of the useful functions provided by this module:
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ismodule(), isclass(), ismethod(), isfunction(), isgeneratorfunction(),
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isgenerator(), istraceback(), isframe(), iscode(), isbuiltin(),
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isroutine() - check object types
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getmembers() - get members of an object that satisfy a given condition
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getfile(), getsourcefile(), getsource() - find an object's source code
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getdoc(), getcomments() - get documentation on an object
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getmodule() - determine the module that an object came from
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getclasstree() - arrange classes so as to represent their hierarchy
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getargvalues(), getcallargs() - get info about function arguments
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getfullargspec() - same, with support for Python 3 features
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formatargspec(), formatargvalues() - format an argument spec
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getouterframes(), getinnerframes() - get info about frames
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currentframe() - get the current stack frame
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stack(), trace() - get info about frames on the stack or in a traceback
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signature() - get a Signature object for the callable
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"""
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# This module is in the public domain. No warranties.
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__author__ = ('Ka-Ping Yee <ping@lfw.org>',
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'Yury Selivanov <yselivanov@sprymix.com>')
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import abc
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import ast
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import dis
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import collections.abc
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import enum
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import importlib.machinery
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import itertools
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import linecache
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import os
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import re
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import sys
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import tokenize
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import token
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import types
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import warnings
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import functools
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import builtins
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from operator import attrgetter
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from collections import namedtuple, OrderedDict
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# Create constants for the compiler flags in Include/code.h
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# We try to get them from dis to avoid duplication
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mod_dict = globals()
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for k, v in dis.COMPILER_FLAG_NAMES.items():
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mod_dict["CO_" + v] = k
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# See Include/object.h
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TPFLAGS_IS_ABSTRACT = 1 << 20
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# ----------------------------------------------------------- type-checking
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def ismodule(object):
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"""Return true if the object is a module.
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Module objects provide these attributes:
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__cached__ pathname to byte compiled file
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__doc__ documentation string
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__file__ filename (missing for built-in modules)"""
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return isinstance(object, types.ModuleType)
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def isclass(object):
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"""Return true if the object is a class.
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Class objects provide these attributes:
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__doc__ documentation string
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__module__ name of module in which this class was defined"""
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return isinstance(object, type)
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def ismethod(object):
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"""Return true if the object is an instance method.
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Instance method objects provide these attributes:
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__doc__ documentation string
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__name__ name with which this method was defined
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__func__ function object containing implementation of method
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__self__ instance to which this method is bound"""
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return isinstance(object, types.MethodType)
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def ismethoddescriptor(object):
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"""Return true if the object is a method descriptor.
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But not if ismethod() or isclass() or isfunction() are true.
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This is new in Python 2.2, and, for example, is true of int.__add__.
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An object passing this test has a __get__ attribute but not a __set__
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attribute, but beyond that the set of attributes varies. __name__ is
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usually sensible, and __doc__ often is.
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Methods implemented via descriptors that also pass one of the other
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tests return false from the ismethoddescriptor() test, simply because
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the other tests promise more -- you can, e.g., count on having the
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__func__ attribute (etc) when an object passes ismethod()."""
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if isclass(object) or ismethod(object) or isfunction(object):
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# mutual exclusion
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return False
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tp = type(object)
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return hasattr(tp, "__get__") and not hasattr(tp, "__set__")
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def isdatadescriptor(object):
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"""Return true if the object is a data descriptor.
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Data descriptors have both a __get__ and a __set__ attribute. Examples are
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properties (defined in Python) and getsets and members (defined in C).
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Typically, data descriptors will also have __name__ and __doc__ attributes
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(properties, getsets, and members have both of these attributes), but this
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is not guaranteed."""
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if isclass(object) or ismethod(object) or isfunction(object):
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# mutual exclusion
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return False
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tp = type(object)
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return hasattr(tp, "__set__") and hasattr(tp, "__get__")
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if hasattr(types, 'MemberDescriptorType'):
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# CPython and equivalent
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def ismemberdescriptor(object):
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"""Return true if the object is a member descriptor.
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Member descriptors are specialized descriptors defined in extension
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modules."""
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return isinstance(object, types.MemberDescriptorType)
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else:
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# Other implementations
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def ismemberdescriptor(object):
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"""Return true if the object is a member descriptor.
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Member descriptors are specialized descriptors defined in extension
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modules."""
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return False
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if hasattr(types, 'GetSetDescriptorType'):
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# CPython and equivalent
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def isgetsetdescriptor(object):
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"""Return true if the object is a getset descriptor.
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getset descriptors are specialized descriptors defined in extension
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modules."""
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return isinstance(object, types.GetSetDescriptorType)
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else:
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# Other implementations
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def isgetsetdescriptor(object):
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"""Return true if the object is a getset descriptor.
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getset descriptors are specialized descriptors defined in extension
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modules."""
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return False
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def isfunction(object):
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"""Return true if the object is a user-defined function.
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Function objects provide these attributes:
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__doc__ documentation string
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__name__ name with which this function was defined
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__code__ code object containing compiled function bytecode
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__defaults__ tuple of any default values for arguments
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__globals__ global namespace in which this function was defined
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__annotations__ dict of parameter annotations
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__kwdefaults__ dict of keyword only parameters with defaults"""
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return isinstance(object, types.FunctionType)
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def isgeneratorfunction(object):
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"""Return true if the object is a user-defined generator function.
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Generator function objects provide the same attributes as functions.
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See help(isfunction) for a list of attributes."""
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return bool((isfunction(object) or ismethod(object)) and
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object.__code__.co_flags & CO_GENERATOR)
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def iscoroutinefunction(object):
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"""Return true if the object is a coroutine function.
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Coroutine functions are defined with "async def" syntax.
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"""
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return bool((isfunction(object) or ismethod(object)) and
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object.__code__.co_flags & CO_COROUTINE)
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def isasyncgenfunction(object):
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"""Return true if the object is an asynchronous generator function.
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Asynchronous generator functions are defined with "async def"
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syntax and have "yield" expressions in their body.
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"""
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return bool((isfunction(object) or ismethod(object)) and
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object.__code__.co_flags & CO_ASYNC_GENERATOR)
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def isasyncgen(object):
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"""Return true if the object is an asynchronous generator."""
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return isinstance(object, types.AsyncGeneratorType)
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def isgenerator(object):
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"""Return true if the object is a generator.
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Generator objects provide these attributes:
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__iter__ defined to support iteration over container
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close raises a new GeneratorExit exception inside the
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generator to terminate the iteration
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gi_code code object
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gi_frame frame object or possibly None once the generator has
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been exhausted
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gi_running set to 1 when generator is executing, 0 otherwise
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next return the next item from the container
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send resumes the generator and "sends" a value that becomes
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the result of the current yield-expression
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throw used to raise an exception inside the generator"""
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return isinstance(object, types.GeneratorType)
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def iscoroutine(object):
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"""Return true if the object is a coroutine."""
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return isinstance(object, types.CoroutineType)
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def isawaitable(object):
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"""Return true if object can be passed to an ``await`` expression."""
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return (isinstance(object, types.CoroutineType) or
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isinstance(object, types.GeneratorType) and
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bool(object.gi_code.co_flags & CO_ITERABLE_COROUTINE) or
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isinstance(object, collections.abc.Awaitable))
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def istraceback(object):
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"""Return true if the object is a traceback.
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Traceback objects provide these attributes:
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tb_frame frame object at this level
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tb_lasti index of last attempted instruction in bytecode
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tb_lineno current line number in Python source code
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tb_next next inner traceback object (called by this level)"""
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return isinstance(object, types.TracebackType)
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def isframe(object):
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"""Return true if the object is a frame object.
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Frame objects provide these attributes:
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f_back next outer frame object (this frame's caller)
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f_builtins built-in namespace seen by this frame
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f_code code object being executed in this frame
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f_globals global namespace seen by this frame
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f_lasti index of last attempted instruction in bytecode
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f_lineno current line number in Python source code
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f_locals local namespace seen by this frame
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f_trace tracing function for this frame, or None"""
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return isinstance(object, types.FrameType)
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def iscode(object):
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"""Return true if the object is a code object.
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Code objects provide these attributes:
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co_argcount number of arguments (not including *, ** args
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or keyword only arguments)
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co_code string of raw compiled bytecode
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co_cellvars tuple of names of cell variables
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co_consts tuple of constants used in the bytecode
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co_filename name of file in which this code object was created
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co_firstlineno number of first line in Python source code
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co_flags bitmap: 1=optimized | 2=newlocals | 4=*arg | 8=**arg
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| 16=nested | 32=generator | 64=nofree | 128=coroutine
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| 256=iterable_coroutine | 512=async_generator
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co_freevars tuple of names of free variables
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co_kwonlyargcount number of keyword only arguments (not including ** arg)
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co_lnotab encoded mapping of line numbers to bytecode indices
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co_name name with which this code object was defined
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co_names tuple of names of local variables
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co_nlocals number of local variables
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co_stacksize virtual machine stack space required
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co_varnames tuple of names of arguments and local variables"""
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return isinstance(object, types.CodeType)
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def isbuiltin(object):
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"""Return true if the object is a built-in function or method.
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Built-in functions and methods provide these attributes:
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__doc__ documentation string
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__name__ original name of this function or method
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__self__ instance to which a method is bound, or None"""
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return isinstance(object, types.BuiltinFunctionType)
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def isroutine(object):
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"""Return true if the object is any kind of function or method."""
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return (isbuiltin(object)
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or isfunction(object)
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or ismethod(object)
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or ismethoddescriptor(object))
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def isabstract(object):
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"""Return true if the object is an abstract base class (ABC)."""
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if not isinstance(object, type):
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return False
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if object.__flags__ & TPFLAGS_IS_ABSTRACT:
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return True
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if not issubclass(type(object), abc.ABCMeta):
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return False
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if hasattr(object, '__abstractmethods__'):
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# It looks like ABCMeta.__new__ has finished running;
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# TPFLAGS_IS_ABSTRACT should have been accurate.
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return False
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# It looks like ABCMeta.__new__ has not finished running yet; we're
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# probably in __init_subclass__. We'll look for abstractmethods manually.
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for name, value in object.__dict__.items():
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if getattr(value, "__isabstractmethod__", False):
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return True
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for base in object.__bases__:
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for name in getattr(base, "__abstractmethods__", ()):
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value = getattr(object, name, None)
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if getattr(value, "__isabstractmethod__", False):
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return True
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return False
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def getmembers(object, predicate=None):
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"""Return all members of an object as (name, value) pairs sorted by name.
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Optionally, only return members that satisfy a given predicate."""
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if isclass(object):
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mro = (object,) + getmro(object)
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else:
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mro = ()
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results = []
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processed = set()
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names = dir(object)
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# :dd any DynamicClassAttributes to the list of names if object is a class;
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# this may result in duplicate entries if, for example, a virtual
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# attribute with the same name as a DynamicClassAttribute exists
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try:
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for base in object.__bases__:
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for k, v in base.__dict__.items():
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if isinstance(v, types.DynamicClassAttribute):
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names.append(k)
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except AttributeError:
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pass
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for key in names:
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# First try to get the value via getattr. Some descriptors don't
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# like calling their __get__ (see bug #1785), so fall back to
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# looking in the __dict__.
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try:
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value = getattr(object, key)
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# handle the duplicate key
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if key in processed:
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raise AttributeError
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except AttributeError:
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for base in mro:
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if key in base.__dict__:
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value = base.__dict__[key]
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break
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else:
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# could be a (currently) missing slot member, or a buggy
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# __dir__; discard and move on
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continue
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if not predicate or predicate(value):
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results.append((key, value))
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processed.add(key)
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results.sort(key=lambda pair: pair[0])
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return results
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Attribute = namedtuple('Attribute', 'name kind defining_class object')
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def classify_class_attrs(cls):
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"""Return list of attribute-descriptor tuples.
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For each name in dir(cls), the return list contains a 4-tuple
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with these elements:
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0. The name (a string).
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1. The kind of attribute this is, one of these strings:
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'class method' created via classmethod()
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'static method' created via staticmethod()
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'property' created via property()
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'method' any other flavor of method or descriptor
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'data' not a method
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2. The class which defined this attribute (a class).
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3. The object as obtained by calling getattr; if this fails, or if the
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resulting object does not live anywhere in the class' mro (including
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metaclasses) then the object is looked up in the defining class's
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dict (found by walking the mro).
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If one of the items in dir(cls) is stored in the metaclass it will now
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be discovered and not have None be listed as the class in which it was
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defined. Any items whose home class cannot be discovered are skipped.
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"""
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mro = getmro(cls)
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metamro = getmro(type(cls)) # for attributes stored in the metaclass
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metamro = tuple(cls for cls in metamro if cls not in (type, object))
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class_bases = (cls,) + mro
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all_bases = class_bases + metamro
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names = dir(cls)
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# :dd any DynamicClassAttributes to the list of names;
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# this may result in duplicate entries if, for example, a virtual
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# attribute with the same name as a DynamicClassAttribute exists.
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for base in mro:
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for k, v in base.__dict__.items():
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if isinstance(v, types.DynamicClassAttribute):
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names.append(k)
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result = []
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processed = set()
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for name in names:
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# Get the object associated with the name, and where it was defined.
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# Normal objects will be looked up with both getattr and directly in
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# its class' dict (in case getattr fails [bug #1785], and also to look
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# for a docstring).
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# For DynamicClassAttributes on the second pass we only look in the
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# class's dict.
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#
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# Getting an obj from the __dict__ sometimes reveals more than
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# using getattr. Static and class methods are dramatic examples.
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homecls = None
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get_obj = None
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dict_obj = None
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if name not in processed:
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try:
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if name == '__dict__':
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raise Exception("__dict__ is special, don't want the proxy")
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get_obj = getattr(cls, name)
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except Exception as exc:
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pass
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else:
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homecls = getattr(get_obj, "__objclass__", homecls)
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if homecls not in class_bases:
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# if the resulting object does not live somewhere in the
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# mro, drop it and search the mro manually
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homecls = None
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last_cls = None
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# first look in the classes
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for srch_cls in class_bases:
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srch_obj = getattr(srch_cls, name, None)
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if srch_obj is get_obj:
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last_cls = srch_cls
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# then check the metaclasses
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for srch_cls in metamro:
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try:
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srch_obj = srch_cls.__getattr__(cls, name)
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except AttributeError:
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continue
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if srch_obj is get_obj:
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last_cls = srch_cls
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if last_cls is not None:
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homecls = last_cls
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for base in all_bases:
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if name in base.__dict__:
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dict_obj = base.__dict__[name]
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if homecls not in metamro:
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homecls = base
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break
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if homecls is None:
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# unable to locate the attribute anywhere, most likely due to
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# buggy custom __dir__; discard and move on
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continue
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obj = get_obj if get_obj is not None else dict_obj
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# Classify the object or its descriptor.
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if isinstance(dict_obj, staticmethod):
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kind = "static method"
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obj = dict_obj
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elif isinstance(dict_obj, classmethod):
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kind = "class method"
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obj = dict_obj
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elif isinstance(dict_obj, property):
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kind = "property"
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obj = dict_obj
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elif isroutine(obj):
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kind = "method"
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else:
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kind = "data"
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result.append(Attribute(name, kind, homecls, obj))
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processed.add(name)
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return result
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|
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# ----------------------------------------------------------- class helpers
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def getmro(cls):
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"Return tuple of base classes (including cls) in method resolution order."
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return cls.__mro__
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|
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# -------------------------------------------------------- function helpers
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def unwrap(func, *, stop=None):
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"""Get the object wrapped by *func*.
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Follows the chain of :attr:`__wrapped__` attributes returning the last
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object in the chain.
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*stop* is an optional callback accepting an object in the wrapper chain
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as its sole argument that allows the unwrapping to be terminated early if
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the callback returns a true value. If the callback never returns a true
|
|
value, the last object in the chain is returned as usual. For example,
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:func:`signature` uses this to stop unwrapping if any object in the
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chain has a ``__signature__`` attribute defined.
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:exc:`ValueError` is raised if a cycle is encountered.
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|
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"""
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if stop is None:
|
|
def _is_wrapper(f):
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return hasattr(f, '__wrapped__')
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else:
|
|
def _is_wrapper(f):
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return hasattr(f, '__wrapped__') and not stop(f)
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|
f = func # remember the original func for error reporting
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|
# Memoise by id to tolerate non-hashable objects, but store objects to
|
|
# ensure they aren't destroyed, which would allow their IDs to be reused.
|
|
memo = {id(f): f}
|
|
recursion_limit = sys.getrecursionlimit()
|
|
while _is_wrapper(func):
|
|
func = func.__wrapped__
|
|
id_func = id(func)
|
|
if (id_func in memo) or (len(memo) >= recursion_limit):
|
|
raise ValueError('wrapper loop when unwrapping {!r}'.format(f))
|
|
memo[id_func] = func
|
|
return func
|
|
|
|
# -------------------------------------------------- source code extraction
|
|
def indentsize(line):
|
|
"""Return the indent size, in spaces, at the start of a line of text."""
|
|
expline = line.expandtabs()
|
|
return len(expline) - len(expline.lstrip())
|
|
|
|
def _findclass(func):
|
|
cls = sys.modules.get(func.__module__)
|
|
if cls is None:
|
|
return None
|
|
for name in func.__qualname__.split('.')[:-1]:
|
|
cls = getattr(cls, name)
|
|
if not isclass(cls):
|
|
return None
|
|
return cls
|
|
|
|
def _finddoc(obj):
|
|
if isclass(obj):
|
|
for base in obj.__mro__:
|
|
if base is not object:
|
|
try:
|
|
doc = base.__doc__
|
|
except AttributeError:
|
|
continue
|
|
if doc is not None:
|
|
return doc
|
|
return None
|
|
|
|
if ismethod(obj):
|
|
name = obj.__func__.__name__
|
|
self = obj.__self__
|
|
if (isclass(self) and
|
|
getattr(getattr(self, name, None), '__func__') is obj.__func__):
|
|
# classmethod
|
|
cls = self
|
|
else:
|
|
cls = self.__class__
|
|
elif isfunction(obj):
|
|
name = obj.__name__
|
|
cls = _findclass(obj)
|
|
if cls is None or getattr(cls, name) is not obj:
|
|
return None
|
|
elif isbuiltin(obj):
|
|
name = obj.__name__
|
|
self = obj.__self__
|
|
if (isclass(self) and
|
|
self.__qualname__ + '.' + name == obj.__qualname__):
|
|
# classmethod
|
|
cls = self
|
|
else:
|
|
cls = self.__class__
|
|
# Should be tested before isdatadescriptor().
|
|
elif isinstance(obj, property):
|
|
func = obj.fget
|
|
name = func.__name__
|
|
cls = _findclass(func)
|
|
if cls is None or getattr(cls, name) is not obj:
|
|
return None
|
|
elif ismethoddescriptor(obj) or isdatadescriptor(obj):
|
|
name = obj.__name__
|
|
cls = obj.__objclass__
|
|
if getattr(cls, name) is not obj:
|
|
return None
|
|
else:
|
|
return None
|
|
|
|
for base in cls.__mro__:
|
|
try:
|
|
doc = getattr(base, name).__doc__
|
|
except AttributeError:
|
|
continue
|
|
if doc is not None:
|
|
return doc
|
|
return None
|
|
|
|
def getdoc(object):
|
|
"""Get the documentation string for an object.
|
|
|
|
All tabs are expanded to spaces. To clean up docstrings that are
|
|
indented to line up with blocks of code, any whitespace than can be
|
|
uniformly removed from the second line onwards is removed."""
|
|
try:
|
|
doc = object.__doc__
|
|
except AttributeError:
|
|
return None
|
|
if doc is None:
|
|
try:
|
|
doc = _finddoc(object)
|
|
except (AttributeError, TypeError):
|
|
return None
|
|
if not isinstance(doc, str):
|
|
return None
|
|
return cleandoc(doc)
|
|
|
|
def cleandoc(doc):
|
|
"""Clean up indentation from docstrings.
|
|
|
|
Any whitespace that can be uniformly removed from the second line
|
|
onwards is removed."""
|
|
try:
|
|
lines = doc.expandtabs().split('\n')
|
|
except UnicodeError:
|
|
return None
|
|
else:
|
|
# Find minimum indentation of any non-blank lines after first line.
|
|
margin = sys.maxsize
|
|
for line in lines[1:]:
|
|
content = len(line.lstrip())
|
|
if content:
|
|
indent = len(line) - content
|
|
margin = min(margin, indent)
|
|
# Remove indentation.
|
|
if lines:
|
|
lines[0] = lines[0].lstrip()
|
|
if margin < sys.maxsize:
|
|
for i in range(1, len(lines)): lines[i] = lines[i][margin:]
|
|
# Remove any trailing or leading blank lines.
|
|
while lines and not lines[-1]:
|
|
lines.pop()
|
|
while lines and not lines[0]:
|
|
lines.pop(0)
|
|
return '\n'.join(lines)
|
|
|
|
def getfile(object):
|
|
"""Work out which source or compiled file an object was defined in."""
|
|
if ismodule(object):
|
|
if hasattr(object, '__file__'):
|
|
return object.__file__
|
|
raise TypeError('{!r} is a built-in module'.format(object))
|
|
if isclass(object):
|
|
if hasattr(object, '__module__'):
|
|
object = sys.modules.get(object.__module__)
|
|
if hasattr(object, '__file__'):
|
|
return object.__file__
|
|
raise TypeError('{!r} is a built-in class'.format(object))
|
|
if ismethod(object):
|
|
object = object.__func__
|
|
if isfunction(object):
|
|
object = object.__code__
|
|
if istraceback(object):
|
|
object = object.tb_frame
|
|
if isframe(object):
|
|
object = object.f_code
|
|
if iscode(object):
|
|
return object.co_filename
|
|
raise TypeError('{!r} is not a module, class, method, '
|
|
'function, traceback, frame, or code object'.format(object))
|
|
|
|
def getmodulename(path):
|
|
"""Return the module name for a given file, or None."""
|
|
fname = os.path.basename(path)
|
|
# Check for paths that look like an actual module file
|
|
suffixes = [(-len(suffix), suffix)
|
|
for suffix in importlib.machinery.all_suffixes()]
|
|
suffixes.sort() # try longest suffixes first, in case they overlap
|
|
for neglen, suffix in suffixes:
|
|
if fname.endswith(suffix):
|
|
return fname[:neglen]
|
|
return None
|
|
|
|
def getsourcefile(object):
|
|
"""Return the filename that can be used to locate an object's source.
|
|
Return None if no way can be identified to get the source.
|
|
"""
|
|
filename = getfile(object)
|
|
all_bytecode_suffixes = importlib.machinery.DEBUG_BYTECODE_SUFFIXES[:]
|
|
all_bytecode_suffixes += importlib.machinery.OPTIMIZED_BYTECODE_SUFFIXES[:]
|
|
if any(filename.endswith(s) for s in all_bytecode_suffixes):
|
|
filename = (os.path.splitext(filename)[0] +
|
|
importlib.machinery.SOURCE_SUFFIXES[0])
|
|
elif any(filename.endswith(s) for s in
|
|
importlib.machinery.EXTENSION_SUFFIXES):
|
|
return None
|
|
if os.path.exists(filename):
|
|
return filename
|
|
# only return a non-existent filename if the module has a PEP 302 loader
|
|
if getattr(getmodule(object, filename), '__loader__', None) is not None:
|
|
return filename
|
|
# or it is in the linecache
|
|
if filename in linecache.cache:
|
|
return filename
|
|
|
|
def getabsfile(object, _filename=None):
|
|
"""Return an absolute path to the source or compiled file for an object.
|
|
|
|
The idea is for each object to have a unique origin, so this routine
|
|
normalizes the result as much as possible."""
|
|
if _filename is None:
|
|
_filename = getsourcefile(object) or getfile(object)
|
|
return os.path.normcase(os.path.abspath(_filename))
|
|
|
|
modulesbyfile = {}
|
|
_filesbymodname = {}
|
|
|
|
def getmodule(object, _filename=None):
|
|
"""Return the module an object was defined in, or None if not found."""
|
|
if ismodule(object):
|
|
return object
|
|
if hasattr(object, '__module__'):
|
|
return sys.modules.get(object.__module__)
|
|
# Try the filename to modulename cache
|
|
if _filename is not None and _filename in modulesbyfile:
|
|
return sys.modules.get(modulesbyfile[_filename])
|
|
# Try the cache again with the absolute file name
|
|
try:
|
|
file = getabsfile(object, _filename)
|
|
except TypeError:
|
|
return None
|
|
if file in modulesbyfile:
|
|
return sys.modules.get(modulesbyfile[file])
|
|
# Update the filename to module name cache and check yet again
|
|
# Copy sys.modules in order to cope with changes while iterating
|
|
for modname, module in list(sys.modules.items()):
|
|
if ismodule(module) and hasattr(module, '__file__'):
|
|
f = module.__file__
|
|
if f == _filesbymodname.get(modname, None):
|
|
# Have already mapped this module, so skip it
|
|
continue
|
|
_filesbymodname[modname] = f
|
|
f = getabsfile(module)
|
|
# Always map to the name the module knows itself by
|
|
modulesbyfile[f] = modulesbyfile[
|
|
os.path.realpath(f)] = module.__name__
|
|
if file in modulesbyfile:
|
|
return sys.modules.get(modulesbyfile[file])
|
|
# Check the main module
|
|
main = sys.modules['__main__']
|
|
if not hasattr(object, '__name__'):
|
|
return None
|
|
if hasattr(main, object.__name__):
|
|
mainobject = getattr(main, object.__name__)
|
|
if mainobject is object:
|
|
return main
|
|
# Check builtins
|
|
builtin = sys.modules['builtins']
|
|
if hasattr(builtin, object.__name__):
|
|
builtinobject = getattr(builtin, object.__name__)
|
|
if builtinobject is object:
|
|
return builtin
|
|
|
|
def findsource(object):
|
|
"""Return the entire source file and starting line number for an object.
|
|
|
|
The argument may be a module, class, method, function, traceback, frame,
|
|
or code object. The source code is returned as a list of all the lines
|
|
in the file and the line number indexes a line in that list. An OSError
|
|
is raised if the source code cannot be retrieved."""
|
|
|
|
file = getsourcefile(object)
|
|
if file:
|
|
# Invalidate cache if needed.
|
|
linecache.checkcache(file)
|
|
else:
|
|
file = getfile(object)
|
|
# Allow filenames in form of "<something>" to pass through.
|
|
# `doctest` monkeypatches `linecache` module to enable
|
|
# inspection, so let `linecache.getlines` to be called.
|
|
if not (file.startswith('<') and file.endswith('>')):
|
|
raise OSError('source code not available')
|
|
|
|
module = getmodule(object, file)
|
|
if module:
|
|
lines = linecache.getlines(file, module.__dict__)
|
|
else:
|
|
lines = linecache.getlines(file)
|
|
if not lines:
|
|
raise OSError('could not get source code')
|
|
|
|
if ismodule(object):
|
|
return lines, 0
|
|
|
|
if isclass(object):
|
|
name = object.__name__
|
|
pat = re.compile(r'^(\s*)class\s*' + name + r'\b')
|
|
# make some effort to find the best matching class definition:
|
|
# use the one with the least indentation, which is the one
|
|
# that's most probably not inside a function definition.
|
|
candidates = []
|
|
for i in range(len(lines)):
|
|
match = pat.match(lines[i])
|
|
if match:
|
|
# if it's at toplevel, it's already the best one
|
|
if lines[i][0] == 'c':
|
|
return lines, i
|
|
# else add whitespace to candidate list
|
|
candidates.append((match.group(1), i))
|
|
if candidates:
|
|
# this will sort by whitespace, and by line number,
|
|
# less whitespace first
|
|
candidates.sort()
|
|
return lines, candidates[0][1]
|
|
else:
|
|
raise OSError('could not find class definition')
|
|
|
|
if ismethod(object):
|
|
object = object.__func__
|
|
if isfunction(object):
|
|
object = object.__code__
|
|
if istraceback(object):
|
|
object = object.tb_frame
|
|
if isframe(object):
|
|
object = object.f_code
|
|
if iscode(object):
|
|
if not hasattr(object, 'co_firstlineno'):
|
|
raise OSError('could not find function definition')
|
|
lnum = object.co_firstlineno - 1
|
|
pat = re.compile(r'^(\s*def\s)|(\s*async\s+def\s)|(.*(?<!\w)lambda(:|\s))|^(\s*@)')
|
|
while lnum > 0:
|
|
if pat.match(lines[lnum]): break
|
|
lnum = lnum - 1
|
|
return lines, lnum
|
|
raise OSError('could not find code object')
|
|
|
|
def getcomments(object):
|
|
"""Get lines of comments immediately preceding an object's source code.
|
|
|
|
Returns None when source can't be found.
|
|
"""
|
|
try:
|
|
lines, lnum = findsource(object)
|
|
except (OSError, TypeError):
|
|
return None
|
|
|
|
if ismodule(object):
|
|
# Look for a comment block at the top of the file.
|
|
start = 0
|
|
if lines and lines[0][:2] == '#!': start = 1
|
|
while start < len(lines) and lines[start].strip() in ('', '#'):
|
|
start = start + 1
|
|
if start < len(lines) and lines[start][:1] == '#':
|
|
comments = []
|
|
end = start
|
|
while end < len(lines) and lines[end][:1] == '#':
|
|
comments.append(lines[end].expandtabs())
|
|
end = end + 1
|
|
return ''.join(comments)
|
|
|
|
# Look for a preceding block of comments at the same indentation.
|
|
elif lnum > 0:
|
|
indent = indentsize(lines[lnum])
|
|
end = lnum - 1
|
|
if end >= 0 and lines[end].lstrip()[:1] == '#' and \
|
|
indentsize(lines[end]) == indent:
|
|
comments = [lines[end].expandtabs().lstrip()]
|
|
if end > 0:
|
|
end = end - 1
|
|
comment = lines[end].expandtabs().lstrip()
|
|
while comment[:1] == '#' and indentsize(lines[end]) == indent:
|
|
comments[:0] = [comment]
|
|
end = end - 1
|
|
if end < 0: break
|
|
comment = lines[end].expandtabs().lstrip()
|
|
while comments and comments[0].strip() == '#':
|
|
comments[:1] = []
|
|
while comments and comments[-1].strip() == '#':
|
|
comments[-1:] = []
|
|
return ''.join(comments)
|
|
|
|
class EndOfBlock(Exception): pass
|
|
|
|
class BlockFinder:
|
|
"""Provide a tokeneater() method to detect the end of a code block."""
|
|
def __init__(self):
|
|
self.indent = 0
|
|
self.islambda = False
|
|
self.started = False
|
|
self.passline = False
|
|
self.indecorator = False
|
|
self.decoratorhasargs = False
|
|
self.last = 1
|
|
|
|
def tokeneater(self, type, token, srowcol, erowcol, line):
|
|
if not self.started and not self.indecorator:
|
|
# skip any decorators
|
|
if token == "@":
|
|
self.indecorator = True
|
|
# look for the first "def", "class" or "lambda"
|
|
elif token in ("def", "class", "lambda"):
|
|
if token == "lambda":
|
|
self.islambda = True
|
|
self.started = True
|
|
self.passline = True # skip to the end of the line
|
|
elif token == "(":
|
|
if self.indecorator:
|
|
self.decoratorhasargs = True
|
|
elif token == ")":
|
|
if self.indecorator:
|
|
self.indecorator = False
|
|
self.decoratorhasargs = False
|
|
elif type == tokenize.NEWLINE:
|
|
self.passline = False # stop skipping when a NEWLINE is seen
|
|
self.last = srowcol[0]
|
|
if self.islambda: # lambdas always end at the first NEWLINE
|
|
raise EndOfBlock
|
|
# hitting a NEWLINE when in a decorator without args
|
|
# ends the decorator
|
|
if self.indecorator and not self.decoratorhasargs:
|
|
self.indecorator = False
|
|
elif self.passline:
|
|
pass
|
|
elif type == tokenize.INDENT:
|
|
self.indent = self.indent + 1
|
|
self.passline = True
|
|
elif type == tokenize.DEDENT:
|
|
self.indent = self.indent - 1
|
|
# the end of matching indent/dedent pairs end a block
|
|
# (note that this only works for "def"/"class" blocks,
|
|
# not e.g. for "if: else:" or "try: finally:" blocks)
|
|
if self.indent <= 0:
|
|
raise EndOfBlock
|
|
elif self.indent == 0 and type not in (tokenize.COMMENT, tokenize.NL):
|
|
# any other token on the same indentation level end the previous
|
|
# block as well, except the pseudo-tokens COMMENT and NL.
|
|
raise EndOfBlock
|
|
|
|
def getblock(lines):
|
|
"""Extract the block of code at the top of the given list of lines."""
|
|
blockfinder = BlockFinder()
|
|
try:
|
|
tokens = tokenize.generate_tokens(iter(lines).__next__)
|
|
for _token in tokens:
|
|
blockfinder.tokeneater(*_token)
|
|
except (EndOfBlock, IndentationError):
|
|
pass
|
|
return lines[:blockfinder.last]
|
|
|
|
def getsourcelines(object):
|
|
"""Return a list of source lines and starting line number for an object.
|
|
|
|
The argument may be a module, class, method, function, traceback, frame,
|
|
or code object. The source code is returned as a list of the lines
|
|
corresponding to the object and the line number indicates where in the
|
|
original source file the first line of code was found. An OSError is
|
|
raised if the source code cannot be retrieved."""
|
|
object = unwrap(object)
|
|
lines, lnum = findsource(object)
|
|
|
|
if ismodule(object):
|
|
return lines, 0
|
|
else:
|
|
return getblock(lines[lnum:]), lnum + 1
|
|
|
|
def getsource(object):
|
|
"""Return the text of the source code for an object.
|
|
|
|
The argument may be a module, class, method, function, traceback, frame,
|
|
or code object. The source code is returned as a single string. An
|
|
OSError is raised if the source code cannot be retrieved."""
|
|
lines, lnum = getsourcelines(object)
|
|
return ''.join(lines)
|
|
|
|
# --------------------------------------------------- class tree extraction
|
|
def walktree(classes, children, parent):
|
|
"""Recursive helper function for getclasstree()."""
|
|
results = []
|
|
classes.sort(key=attrgetter('__module__', '__name__'))
|
|
for c in classes:
|
|
results.append((c, c.__bases__))
|
|
if c in children:
|
|
results.append(walktree(children[c], children, c))
|
|
return results
|
|
|
|
def getclasstree(classes, unique=False):
|
|
"""Arrange the given list of classes into a hierarchy of nested lists.
|
|
|
|
Where a nested list appears, it contains classes derived from the class
|
|
whose entry immediately precedes the list. Each entry is a 2-tuple
|
|
containing a class and a tuple of its base classes. If the 'unique'
|
|
argument is true, exactly one entry appears in the returned structure
|
|
for each class in the given list. Otherwise, classes using multiple
|
|
inheritance and their descendants will appear multiple times."""
|
|
children = {}
|
|
roots = []
|
|
for c in classes:
|
|
if c.__bases__:
|
|
for parent in c.__bases__:
|
|
if not parent in children:
|
|
children[parent] = []
|
|
if c not in children[parent]:
|
|
children[parent].append(c)
|
|
if unique and parent in classes: break
|
|
elif c not in roots:
|
|
roots.append(c)
|
|
for parent in children:
|
|
if parent not in classes:
|
|
roots.append(parent)
|
|
return walktree(roots, children, None)
|
|
|
|
# ------------------------------------------------ argument list extraction
|
|
Arguments = namedtuple('Arguments', 'args, varargs, varkw')
|
|
|
|
def getargs(co):
|
|
"""Get information about the arguments accepted by a code object.
|
|
|
|
Three things are returned: (args, varargs, varkw), where
|
|
'args' is the list of argument names. Keyword-only arguments are
|
|
appended. 'varargs' and 'varkw' are the names of the * and **
|
|
arguments or None."""
|
|
args, varargs, kwonlyargs, varkw = _getfullargs(co)
|
|
return Arguments(args + kwonlyargs, varargs, varkw)
|
|
|
|
def _getfullargs(co):
|
|
"""Get information about the arguments accepted by a code object.
|
|
|
|
Four things are returned: (args, varargs, kwonlyargs, varkw), where
|
|
'args' and 'kwonlyargs' are lists of argument names, and 'varargs'
|
|
and 'varkw' are the names of the * and ** arguments or None."""
|
|
|
|
if not iscode(co):
|
|
raise TypeError('{!r} is not a code object'.format(co))
|
|
|
|
nargs = co.co_argcount
|
|
names = co.co_varnames
|
|
nkwargs = co.co_kwonlyargcount
|
|
args = list(names[:nargs])
|
|
kwonlyargs = list(names[nargs:nargs+nkwargs])
|
|
step = 0
|
|
|
|
nargs += nkwargs
|
|
varargs = None
|
|
if co.co_flags & CO_VARARGS:
|
|
varargs = co.co_varnames[nargs]
|
|
nargs = nargs + 1
|
|
varkw = None
|
|
if co.co_flags & CO_VARKEYWORDS:
|
|
varkw = co.co_varnames[nargs]
|
|
return args, varargs, kwonlyargs, varkw
|
|
|
|
|
|
ArgSpec = namedtuple('ArgSpec', 'args varargs keywords defaults')
|
|
|
|
def getargspec(func):
|
|
"""Get the names and default values of a function's parameters.
|
|
|
|
A tuple of four things is returned: (args, varargs, keywords, defaults).
|
|
'args' is a list of the argument names, including keyword-only argument names.
|
|
'varargs' and 'keywords' are the names of the * and ** parameters or None.
|
|
'defaults' is an n-tuple of the default values of the last n parameters.
|
|
|
|
This function is deprecated, as it does not support annotations or
|
|
keyword-only parameters and will raise ValueError if either is present
|
|
on the supplied callable.
|
|
|
|
For a more structured introspection API, use inspect.signature() instead.
|
|
|
|
Alternatively, use getfullargspec() for an API with a similar namedtuple
|
|
based interface, but full support for annotations and keyword-only
|
|
parameters.
|
|
"""
|
|
warnings.warn("inspect.getargspec() is deprecated, "
|
|
"use inspect.signature() or inspect.getfullargspec()",
|
|
DeprecationWarning, stacklevel=2)
|
|
args, varargs, varkw, defaults, kwonlyargs, kwonlydefaults, ann = \
|
|
getfullargspec(func)
|
|
if kwonlyargs or ann:
|
|
raise ValueError("Function has keyword-only parameters or annotations"
|
|
", use getfullargspec() API which can support them")
|
|
return ArgSpec(args, varargs, varkw, defaults)
|
|
|
|
FullArgSpec = namedtuple('FullArgSpec',
|
|
'args, varargs, varkw, defaults, kwonlyargs, kwonlydefaults, annotations')
|
|
|
|
def getfullargspec(func):
|
|
"""Get the names and default values of a callable object's parameters.
|
|
|
|
A tuple of seven things is returned:
|
|
(args, varargs, varkw, defaults, kwonlyargs, kwonlydefaults, annotations).
|
|
'args' is a list of the parameter names.
|
|
'varargs' and 'varkw' are the names of the * and ** parameters or None.
|
|
'defaults' is an n-tuple of the default values of the last n parameters.
|
|
'kwonlyargs' is a list of keyword-only parameter names.
|
|
'kwonlydefaults' is a dictionary mapping names from kwonlyargs to defaults.
|
|
'annotations' is a dictionary mapping parameter names to annotations.
|
|
|
|
Notable differences from inspect.signature():
|
|
- the "self" parameter is always reported, even for bound methods
|
|
- wrapper chains defined by __wrapped__ *not* unwrapped automatically
|
|
"""
|
|
|
|
try:
|
|
# Re: `skip_bound_arg=False`
|
|
#
|
|
# There is a notable difference in behaviour between getfullargspec
|
|
# and Signature: the former always returns 'self' parameter for bound
|
|
# methods, whereas the Signature always shows the actual calling
|
|
# signature of the passed object.
|
|
#
|
|
# To simulate this behaviour, we "unbind" bound methods, to trick
|
|
# inspect.signature to always return their first parameter ("self",
|
|
# usually)
|
|
|
|
# Re: `follow_wrapper_chains=False`
|
|
#
|
|
# getfullargspec() historically ignored __wrapped__ attributes,
|
|
# so we ensure that remains the case in 3.3+
|
|
|
|
sig = _signature_from_callable(func,
|
|
follow_wrapper_chains=False,
|
|
skip_bound_arg=False,
|
|
sigcls=Signature)
|
|
except Exception as ex:
|
|
# Most of the times 'signature' will raise ValueError.
|
|
# But, it can also raise AttributeError, and, maybe something
|
|
# else. So to be fully backwards compatible, we catch all
|
|
# possible exceptions here, and reraise a TypeError.
|
|
raise TypeError('unsupported callable') from ex
|
|
|
|
args = []
|
|
varargs = None
|
|
varkw = None
|
|
kwonlyargs = []
|
|
defaults = ()
|
|
annotations = {}
|
|
defaults = ()
|
|
kwdefaults = {}
|
|
|
|
if sig.return_annotation is not sig.empty:
|
|
annotations['return'] = sig.return_annotation
|
|
|
|
for param in sig.parameters.values():
|
|
kind = param.kind
|
|
name = param.name
|
|
|
|
if kind is _POSITIONAL_ONLY:
|
|
args.append(name)
|
|
elif kind is _POSITIONAL_OR_KEYWORD:
|
|
args.append(name)
|
|
if param.default is not param.empty:
|
|
defaults += (param.default,)
|
|
elif kind is _VAR_POSITIONAL:
|
|
varargs = name
|
|
elif kind is _KEYWORD_ONLY:
|
|
kwonlyargs.append(name)
|
|
if param.default is not param.empty:
|
|
kwdefaults[name] = param.default
|
|
elif kind is _VAR_KEYWORD:
|
|
varkw = name
|
|
|
|
if param.annotation is not param.empty:
|
|
annotations[name] = param.annotation
|
|
|
|
if not kwdefaults:
|
|
# compatibility with 'func.__kwdefaults__'
|
|
kwdefaults = None
|
|
|
|
if not defaults:
|
|
# compatibility with 'func.__defaults__'
|
|
defaults = None
|
|
|
|
return FullArgSpec(args, varargs, varkw, defaults,
|
|
kwonlyargs, kwdefaults, annotations)
|
|
|
|
|
|
ArgInfo = namedtuple('ArgInfo', 'args varargs keywords locals')
|
|
|
|
def getargvalues(frame):
|
|
"""Get information about arguments passed into a particular frame.
|
|
|
|
A tuple of four things is returned: (args, varargs, varkw, locals).
|
|
'args' is a list of the argument names.
|
|
'varargs' and 'varkw' are the names of the * and ** arguments or None.
|
|
'locals' is the locals dictionary of the given frame."""
|
|
args, varargs, varkw = getargs(frame.f_code)
|
|
return ArgInfo(args, varargs, varkw, frame.f_locals)
|
|
|
|
def formatannotation(annotation, base_module=None):
|
|
if getattr(annotation, '__module__', None) == 'typing':
|
|
return repr(annotation).replace('typing.', '')
|
|
if isinstance(annotation, type):
|
|
if annotation.__module__ in ('builtins', base_module):
|
|
return annotation.__qualname__
|
|
return annotation.__module__+'.'+annotation.__qualname__
|
|
return repr(annotation)
|
|
|
|
def formatannotationrelativeto(object):
|
|
module = getattr(object, '__module__', None)
|
|
def _formatannotation(annotation):
|
|
return formatannotation(annotation, module)
|
|
return _formatannotation
|
|
|
|
def formatargspec(args, varargs=None, varkw=None, defaults=None,
|
|
kwonlyargs=(), kwonlydefaults={}, annotations={},
|
|
formatarg=str,
|
|
formatvarargs=lambda name: '*' + name,
|
|
formatvarkw=lambda name: '**' + name,
|
|
formatvalue=lambda value: '=' + repr(value),
|
|
formatreturns=lambda text: ' -> ' + text,
|
|
formatannotation=formatannotation):
|
|
"""Format an argument spec from the values returned by getfullargspec.
|
|
|
|
The first seven arguments are (args, varargs, varkw, defaults,
|
|
kwonlyargs, kwonlydefaults, annotations). The other five arguments
|
|
are the corresponding optional formatting functions that are called to
|
|
turn names and values into strings. The last argument is an optional
|
|
function to format the sequence of arguments."""
|
|
def formatargandannotation(arg):
|
|
result = formatarg(arg)
|
|
if arg in annotations:
|
|
result += ': ' + formatannotation(annotations[arg])
|
|
return result
|
|
specs = []
|
|
if defaults:
|
|
firstdefault = len(args) - len(defaults)
|
|
for i, arg in enumerate(args):
|
|
spec = formatargandannotation(arg)
|
|
if defaults and i >= firstdefault:
|
|
spec = spec + formatvalue(defaults[i - firstdefault])
|
|
specs.append(spec)
|
|
if varargs is not None:
|
|
specs.append(formatvarargs(formatargandannotation(varargs)))
|
|
else:
|
|
if kwonlyargs:
|
|
specs.append('*')
|
|
if kwonlyargs:
|
|
for kwonlyarg in kwonlyargs:
|
|
spec = formatargandannotation(kwonlyarg)
|
|
if kwonlydefaults and kwonlyarg in kwonlydefaults:
|
|
spec += formatvalue(kwonlydefaults[kwonlyarg])
|
|
specs.append(spec)
|
|
if varkw is not None:
|
|
specs.append(formatvarkw(formatargandannotation(varkw)))
|
|
result = '(' + ', '.join(specs) + ')'
|
|
if 'return' in annotations:
|
|
result += formatreturns(formatannotation(annotations['return']))
|
|
return result
|
|
|
|
def formatargvalues(args, varargs, varkw, locals,
|
|
formatarg=str,
|
|
formatvarargs=lambda name: '*' + name,
|
|
formatvarkw=lambda name: '**' + name,
|
|
formatvalue=lambda value: '=' + repr(value)):
|
|
"""Format an argument spec from the 4 values returned by getargvalues.
|
|
|
|
The first four arguments are (args, varargs, varkw, locals). The
|
|
next four arguments are the corresponding optional formatting functions
|
|
that are called to turn names and values into strings. The ninth
|
|
argument is an optional function to format the sequence of arguments."""
|
|
def convert(name, locals=locals,
|
|
formatarg=formatarg, formatvalue=formatvalue):
|
|
return formatarg(name) + formatvalue(locals[name])
|
|
specs = []
|
|
for i in range(len(args)):
|
|
specs.append(convert(args[i]))
|
|
if varargs:
|
|
specs.append(formatvarargs(varargs) + formatvalue(locals[varargs]))
|
|
if varkw:
|
|
specs.append(formatvarkw(varkw) + formatvalue(locals[varkw]))
|
|
return '(' + ', '.join(specs) + ')'
|
|
|
|
def _missing_arguments(f_name, argnames, pos, values):
|
|
names = [repr(name) for name in argnames if name not in values]
|
|
missing = len(names)
|
|
if missing == 1:
|
|
s = names[0]
|
|
elif missing == 2:
|
|
s = "{} and {}".format(*names)
|
|
else:
|
|
tail = ", {} and {}".format(*names[-2:])
|
|
del names[-2:]
|
|
s = ", ".join(names) + tail
|
|
raise TypeError("%s() missing %i required %s argument%s: %s" %
|
|
(f_name, missing,
|
|
"positional" if pos else "keyword-only",
|
|
"" if missing == 1 else "s", s))
|
|
|
|
def _too_many(f_name, args, kwonly, varargs, defcount, given, values):
|
|
atleast = len(args) - defcount
|
|
kwonly_given = len([arg for arg in kwonly if arg in values])
|
|
if varargs:
|
|
plural = atleast != 1
|
|
sig = "at least %d" % (atleast,)
|
|
elif defcount:
|
|
plural = True
|
|
sig = "from %d to %d" % (atleast, len(args))
|
|
else:
|
|
plural = len(args) != 1
|
|
sig = str(len(args))
|
|
kwonly_sig = ""
|
|
if kwonly_given:
|
|
msg = " positional argument%s (and %d keyword-only argument%s)"
|
|
kwonly_sig = (msg % ("s" if given != 1 else "", kwonly_given,
|
|
"s" if kwonly_given != 1 else ""))
|
|
raise TypeError("%s() takes %s positional argument%s but %d%s %s given" %
|
|
(f_name, sig, "s" if plural else "", given, kwonly_sig,
|
|
"was" if given == 1 and not kwonly_given else "were"))
|
|
|
|
def getcallargs(*func_and_positional, **named):
|
|
"""Get the mapping of arguments to values.
|
|
|
|
A dict is returned, with keys the function argument names (including the
|
|
names of the * and ** arguments, if any), and values the respective bound
|
|
values from 'positional' and 'named'."""
|
|
func = func_and_positional[0]
|
|
positional = func_and_positional[1:]
|
|
spec = getfullargspec(func)
|
|
args, varargs, varkw, defaults, kwonlyargs, kwonlydefaults, ann = spec
|
|
f_name = func.__name__
|
|
arg2value = {}
|
|
|
|
|
|
if ismethod(func) and func.__self__ is not None:
|
|
# implicit 'self' (or 'cls' for classmethods) argument
|
|
positional = (func.__self__,) + positional
|
|
num_pos = len(positional)
|
|
num_args = len(args)
|
|
num_defaults = len(defaults) if defaults else 0
|
|
|
|
n = min(num_pos, num_args)
|
|
for i in range(n):
|
|
arg2value[args[i]] = positional[i]
|
|
if varargs:
|
|
arg2value[varargs] = tuple(positional[n:])
|
|
possible_kwargs = set(args + kwonlyargs)
|
|
if varkw:
|
|
arg2value[varkw] = {}
|
|
for kw, value in named.items():
|
|
if kw not in possible_kwargs:
|
|
if not varkw:
|
|
raise TypeError("%s() got an unexpected keyword argument %r" %
|
|
(f_name, kw))
|
|
arg2value[varkw][kw] = value
|
|
continue
|
|
if kw in arg2value:
|
|
raise TypeError("%s() got multiple values for argument %r" %
|
|
(f_name, kw))
|
|
arg2value[kw] = value
|
|
if num_pos > num_args and not varargs:
|
|
_too_many(f_name, args, kwonlyargs, varargs, num_defaults,
|
|
num_pos, arg2value)
|
|
if num_pos < num_args:
|
|
req = args[:num_args - num_defaults]
|
|
for arg in req:
|
|
if arg not in arg2value:
|
|
_missing_arguments(f_name, req, True, arg2value)
|
|
for i, arg in enumerate(args[num_args - num_defaults:]):
|
|
if arg not in arg2value:
|
|
arg2value[arg] = defaults[i]
|
|
missing = 0
|
|
for kwarg in kwonlyargs:
|
|
if kwarg not in arg2value:
|
|
if kwonlydefaults and kwarg in kwonlydefaults:
|
|
arg2value[kwarg] = kwonlydefaults[kwarg]
|
|
else:
|
|
missing += 1
|
|
if missing:
|
|
_missing_arguments(f_name, kwonlyargs, False, arg2value)
|
|
return arg2value
|
|
|
|
ClosureVars = namedtuple('ClosureVars', 'nonlocals globals builtins unbound')
|
|
|
|
def getclosurevars(func):
|
|
"""
|
|
Get the mapping of free variables to their current values.
|
|
|
|
Returns a named tuple of dicts mapping the current nonlocal, global
|
|
and builtin references as seen by the body of the function. A final
|
|
set of unbound names that could not be resolved is also provided.
|
|
"""
|
|
|
|
if ismethod(func):
|
|
func = func.__func__
|
|
|
|
if not isfunction(func):
|
|
raise TypeError("'{!r}' is not a Python function".format(func))
|
|
|
|
code = func.__code__
|
|
# Nonlocal references are named in co_freevars and resolved
|
|
# by looking them up in __closure__ by positional index
|
|
if func.__closure__ is None:
|
|
nonlocal_vars = {}
|
|
else:
|
|
nonlocal_vars = {
|
|
var : cell.cell_contents
|
|
for var, cell in zip(code.co_freevars, func.__closure__)
|
|
}
|
|
|
|
# Global and builtin references are named in co_names and resolved
|
|
# by looking them up in __globals__ or __builtins__
|
|
global_ns = func.__globals__
|
|
builtin_ns = global_ns.get("__builtins__", builtins.__dict__)
|
|
if ismodule(builtin_ns):
|
|
builtin_ns = builtin_ns.__dict__
|
|
global_vars = {}
|
|
builtin_vars = {}
|
|
unbound_names = set()
|
|
for name in code.co_names:
|
|
if name in ("None", "True", "False"):
|
|
# Because these used to be builtins instead of keywords, they
|
|
# may still show up as name references. We ignore them.
|
|
continue
|
|
try:
|
|
global_vars[name] = global_ns[name]
|
|
except KeyError:
|
|
try:
|
|
builtin_vars[name] = builtin_ns[name]
|
|
except KeyError:
|
|
unbound_names.add(name)
|
|
|
|
return ClosureVars(nonlocal_vars, global_vars,
|
|
builtin_vars, unbound_names)
|
|
|
|
# -------------------------------------------------- stack frame extraction
|
|
|
|
Traceback = namedtuple('Traceback', 'filename lineno function code_context index')
|
|
|
|
def getframeinfo(frame, context=1):
|
|
"""Get information about a frame or traceback object.
|
|
|
|
A tuple of five things is returned: the filename, the line number of
|
|
the current line, the function name, a list of lines of context from
|
|
the source code, and the index of the current line within that list.
|
|
The optional second argument specifies the number of lines of context
|
|
to return, which are centered around the current line."""
|
|
if istraceback(frame):
|
|
lineno = frame.tb_lineno
|
|
frame = frame.tb_frame
|
|
else:
|
|
lineno = frame.f_lineno
|
|
if not isframe(frame):
|
|
raise TypeError('{!r} is not a frame or traceback object'.format(frame))
|
|
|
|
filename = getsourcefile(frame) or getfile(frame)
|
|
if context > 0:
|
|
start = lineno - 1 - context//2
|
|
try:
|
|
lines, lnum = findsource(frame)
|
|
except OSError:
|
|
lines = index = None
|
|
else:
|
|
start = max(0, min(start, len(lines) - context))
|
|
lines = lines[start:start+context]
|
|
index = lineno - 1 - start
|
|
else:
|
|
lines = index = None
|
|
|
|
return Traceback(filename, lineno, frame.f_code.co_name, lines, index)
|
|
|
|
def getlineno(frame):
|
|
"""Get the line number from a frame object, allowing for optimization."""
|
|
# FrameType.f_lineno is now a descriptor that grovels co_lnotab
|
|
return frame.f_lineno
|
|
|
|
FrameInfo = namedtuple('FrameInfo', ('frame',) + Traceback._fields)
|
|
|
|
def getouterframes(frame, context=1):
|
|
"""Get a list of records for a frame and all higher (calling) frames.
|
|
|
|
Each record contains a frame object, filename, line number, function
|
|
name, a list of lines of context, and index within the context."""
|
|
framelist = []
|
|
while frame:
|
|
frameinfo = (frame,) + getframeinfo(frame, context)
|
|
framelist.append(FrameInfo(*frameinfo))
|
|
frame = frame.f_back
|
|
return framelist
|
|
|
|
def getinnerframes(tb, context=1):
|
|
"""Get a list of records for a traceback's frame and all lower frames.
|
|
|
|
Each record contains a frame object, filename, line number, function
|
|
name, a list of lines of context, and index within the context."""
|
|
framelist = []
|
|
while tb:
|
|
frameinfo = (tb.tb_frame,) + getframeinfo(tb, context)
|
|
framelist.append(FrameInfo(*frameinfo))
|
|
tb = tb.tb_next
|
|
return framelist
|
|
|
|
def currentframe():
|
|
"""Return the frame of the caller or None if this is not possible."""
|
|
return sys._getframe(1) if hasattr(sys, "_getframe") else None
|
|
|
|
def stack(context=1):
|
|
"""Return a list of records for the stack above the caller's frame."""
|
|
return getouterframes(sys._getframe(1), context)
|
|
|
|
def trace(context=1):
|
|
"""Return a list of records for the stack below the current exception."""
|
|
return getinnerframes(sys.exc_info()[2], context)
|
|
|
|
|
|
# ------------------------------------------------ static version of getattr
|
|
|
|
_sentinel = object()
|
|
|
|
def _static_getmro(klass):
|
|
return type.__dict__['__mro__'].__get__(klass)
|
|
|
|
def _check_instance(obj, attr):
|
|
instance_dict = {}
|
|
try:
|
|
instance_dict = object.__getattribute__(obj, "__dict__")
|
|
except AttributeError:
|
|
pass
|
|
return dict.get(instance_dict, attr, _sentinel)
|
|
|
|
|
|
def _check_class(klass, attr):
|
|
for entry in _static_getmro(klass):
|
|
if _shadowed_dict(type(entry)) is _sentinel:
|
|
try:
|
|
return entry.__dict__[attr]
|
|
except KeyError:
|
|
pass
|
|
return _sentinel
|
|
|
|
def _is_type(obj):
|
|
try:
|
|
_static_getmro(obj)
|
|
except TypeError:
|
|
return False
|
|
return True
|
|
|
|
def _shadowed_dict(klass):
|
|
dict_attr = type.__dict__["__dict__"]
|
|
for entry in _static_getmro(klass):
|
|
try:
|
|
class_dict = dict_attr.__get__(entry)["__dict__"]
|
|
except KeyError:
|
|
pass
|
|
else:
|
|
if not (type(class_dict) is types.GetSetDescriptorType and
|
|
class_dict.__name__ == "__dict__" and
|
|
class_dict.__objclass__ is entry):
|
|
return class_dict
|
|
return _sentinel
|
|
|
|
def getattr_static(obj, attr, default=_sentinel):
|
|
"""Retrieve attributes without triggering dynamic lookup via the
|
|
descriptor protocol, __getattr__ or __getattribute__.
|
|
|
|
Note: this function may not be able to retrieve all attributes
|
|
that getattr can fetch (like dynamically created attributes)
|
|
and may find attributes that getattr can't (like descriptors
|
|
that raise AttributeError). It can also return descriptor objects
|
|
instead of instance members in some cases. See the
|
|
documentation for details.
|
|
"""
|
|
instance_result = _sentinel
|
|
if not _is_type(obj):
|
|
klass = type(obj)
|
|
dict_attr = _shadowed_dict(klass)
|
|
if (dict_attr is _sentinel or
|
|
type(dict_attr) is types.MemberDescriptorType):
|
|
instance_result = _check_instance(obj, attr)
|
|
else:
|
|
klass = obj
|
|
|
|
klass_result = _check_class(klass, attr)
|
|
|
|
if instance_result is not _sentinel and klass_result is not _sentinel:
|
|
if (_check_class(type(klass_result), '__get__') is not _sentinel and
|
|
_check_class(type(klass_result), '__set__') is not _sentinel):
|
|
return klass_result
|
|
|
|
if instance_result is not _sentinel:
|
|
return instance_result
|
|
if klass_result is not _sentinel:
|
|
return klass_result
|
|
|
|
if obj is klass:
|
|
# for types we check the metaclass too
|
|
for entry in _static_getmro(type(klass)):
|
|
if _shadowed_dict(type(entry)) is _sentinel:
|
|
try:
|
|
return entry.__dict__[attr]
|
|
except KeyError:
|
|
pass
|
|
if default is not _sentinel:
|
|
return default
|
|
raise AttributeError(attr)
|
|
|
|
|
|
# ------------------------------------------------ generator introspection
|
|
|
|
GEN_CREATED = 'GEN_CREATED'
|
|
GEN_RUNNING = 'GEN_RUNNING'
|
|
GEN_SUSPENDED = 'GEN_SUSPENDED'
|
|
GEN_CLOSED = 'GEN_CLOSED'
|
|
|
|
def getgeneratorstate(generator):
|
|
"""Get current state of a generator-iterator.
|
|
|
|
Possible states are:
|
|
GEN_CREATED: Waiting to start execution.
|
|
GEN_RUNNING: Currently being executed by the interpreter.
|
|
GEN_SUSPENDED: Currently suspended at a yield expression.
|
|
GEN_CLOSED: Execution has completed.
|
|
"""
|
|
if generator.gi_running:
|
|
return GEN_RUNNING
|
|
if generator.gi_frame is None:
|
|
return GEN_CLOSED
|
|
if generator.gi_frame.f_lasti == -1:
|
|
return GEN_CREATED
|
|
return GEN_SUSPENDED
|
|
|
|
|
|
def getgeneratorlocals(generator):
|
|
"""
|
|
Get the mapping of generator local variables to their current values.
|
|
|
|
A dict is returned, with the keys the local variable names and values the
|
|
bound values."""
|
|
|
|
if not isgenerator(generator):
|
|
raise TypeError("'{!r}' is not a Python generator".format(generator))
|
|
|
|
frame = getattr(generator, "gi_frame", None)
|
|
if frame is not None:
|
|
return generator.gi_frame.f_locals
|
|
else:
|
|
return {}
|
|
|
|
|
|
# ------------------------------------------------ coroutine introspection
|
|
|
|
CORO_CREATED = 'CORO_CREATED'
|
|
CORO_RUNNING = 'CORO_RUNNING'
|
|
CORO_SUSPENDED = 'CORO_SUSPENDED'
|
|
CORO_CLOSED = 'CORO_CLOSED'
|
|
|
|
def getcoroutinestate(coroutine):
|
|
"""Get current state of a coroutine object.
|
|
|
|
Possible states are:
|
|
CORO_CREATED: Waiting to start execution.
|
|
CORO_RUNNING: Currently being executed by the interpreter.
|
|
CORO_SUSPENDED: Currently suspended at an await expression.
|
|
CORO_CLOSED: Execution has completed.
|
|
"""
|
|
if coroutine.cr_running:
|
|
return CORO_RUNNING
|
|
if coroutine.cr_frame is None:
|
|
return CORO_CLOSED
|
|
if coroutine.cr_frame.f_lasti == -1:
|
|
return CORO_CREATED
|
|
return CORO_SUSPENDED
|
|
|
|
|
|
def getcoroutinelocals(coroutine):
|
|
"""
|
|
Get the mapping of coroutine local variables to their current values.
|
|
|
|
A dict is returned, with the keys the local variable names and values the
|
|
bound values."""
|
|
frame = getattr(coroutine, "cr_frame", None)
|
|
if frame is not None:
|
|
return frame.f_locals
|
|
else:
|
|
return {}
|
|
|
|
|
|
###############################################################################
|
|
### Function Signature Object (PEP 362)
|
|
###############################################################################
|
|
|
|
|
|
_WrapperDescriptor = type(type.__call__)
|
|
_MethodWrapper = type(all.__call__)
|
|
_ClassMethodWrapper = type(int.__dict__['from_bytes'])
|
|
|
|
_NonUserDefinedCallables = (_WrapperDescriptor,
|
|
_MethodWrapper,
|
|
_ClassMethodWrapper,
|
|
types.BuiltinFunctionType)
|
|
|
|
|
|
def _signature_get_user_defined_method(cls, method_name):
|
|
"""Private helper. Checks if ``cls`` has an attribute
|
|
named ``method_name`` and returns it only if it is a
|
|
pure python function.
|
|
"""
|
|
try:
|
|
meth = getattr(cls, method_name)
|
|
except AttributeError:
|
|
return
|
|
else:
|
|
if not isinstance(meth, _NonUserDefinedCallables):
|
|
# Once '__signature__' will be added to 'C'-level
|
|
# callables, this check won't be necessary
|
|
return meth
|
|
|
|
|
|
def _signature_get_partial(wrapped_sig, partial, extra_args=()):
|
|
"""Private helper to calculate how 'wrapped_sig' signature will
|
|
look like after applying a 'functools.partial' object (or alike)
|
|
on it.
|
|
"""
|
|
|
|
old_params = wrapped_sig.parameters
|
|
new_params = OrderedDict(old_params.items())
|
|
|
|
partial_args = partial.args or ()
|
|
partial_keywords = partial.keywords or {}
|
|
|
|
if extra_args:
|
|
partial_args = extra_args + partial_args
|
|
|
|
try:
|
|
ba = wrapped_sig.bind_partial(*partial_args, **partial_keywords)
|
|
except TypeError as ex:
|
|
msg = 'partial object {!r} has incorrect arguments'.format(partial)
|
|
raise ValueError(msg) from ex
|
|
|
|
|
|
transform_to_kwonly = False
|
|
for param_name, param in old_params.items():
|
|
try:
|
|
arg_value = ba.arguments[param_name]
|
|
except KeyError:
|
|
pass
|
|
else:
|
|
if param.kind is _POSITIONAL_ONLY:
|
|
# If positional-only parameter is bound by partial,
|
|
# it effectively disappears from the signature
|
|
new_params.pop(param_name)
|
|
continue
|
|
|
|
if param.kind is _POSITIONAL_OR_KEYWORD:
|
|
if param_name in partial_keywords:
|
|
# This means that this parameter, and all parameters
|
|
# after it should be keyword-only (and var-positional
|
|
# should be removed). Here's why. Consider the following
|
|
# function:
|
|
# foo(a, b, *args, c):
|
|
# pass
|
|
#
|
|
# "partial(foo, a='spam')" will have the following
|
|
# signature: "(*, a='spam', b, c)". Because attempting
|
|
# to call that partial with "(10, 20)" arguments will
|
|
# raise a TypeError, saying that "a" argument received
|
|
# multiple values.
|
|
transform_to_kwonly = True
|
|
# Set the new default value
|
|
new_params[param_name] = param.replace(default=arg_value)
|
|
else:
|
|
# was passed as a positional argument
|
|
new_params.pop(param.name)
|
|
continue
|
|
|
|
if param.kind is _KEYWORD_ONLY:
|
|
# Set the new default value
|
|
new_params[param_name] = param.replace(default=arg_value)
|
|
|
|
if transform_to_kwonly:
|
|
assert param.kind is not _POSITIONAL_ONLY
|
|
|
|
if param.kind is _POSITIONAL_OR_KEYWORD:
|
|
new_param = new_params[param_name].replace(kind=_KEYWORD_ONLY)
|
|
new_params[param_name] = new_param
|
|
new_params.move_to_end(param_name)
|
|
elif param.kind in (_KEYWORD_ONLY, _VAR_KEYWORD):
|
|
new_params.move_to_end(param_name)
|
|
elif param.kind is _VAR_POSITIONAL:
|
|
new_params.pop(param.name)
|
|
|
|
return wrapped_sig.replace(parameters=new_params.values())
|
|
|
|
|
|
def _signature_bound_method(sig):
|
|
"""Private helper to transform signatures for unbound
|
|
functions to bound methods.
|
|
"""
|
|
|
|
params = tuple(sig.parameters.values())
|
|
|
|
if not params or params[0].kind in (_VAR_KEYWORD, _KEYWORD_ONLY):
|
|
raise ValueError('invalid method signature')
|
|
|
|
kind = params[0].kind
|
|
if kind in (_POSITIONAL_OR_KEYWORD, _POSITIONAL_ONLY):
|
|
# Drop first parameter:
|
|
# '(p1, p2[, ...])' -> '(p2[, ...])'
|
|
params = params[1:]
|
|
else:
|
|
if kind is not _VAR_POSITIONAL:
|
|
# Unless we add a new parameter type we never
|
|
# get here
|
|
raise ValueError('invalid argument type')
|
|
# It's a var-positional parameter.
|
|
# Do nothing. '(*args[, ...])' -> '(*args[, ...])'
|
|
|
|
return sig.replace(parameters=params)
|
|
|
|
|
|
def _signature_is_builtin(obj):
|
|
"""Private helper to test if `obj` is a callable that might
|
|
support Argument Clinic's __text_signature__ protocol.
|
|
"""
|
|
return (isbuiltin(obj) or
|
|
ismethoddescriptor(obj) or
|
|
isinstance(obj, _NonUserDefinedCallables) or
|
|
# Can't test 'isinstance(type)' here, as it would
|
|
# also be True for regular python classes
|
|
obj in (type, object))
|
|
|
|
|
|
def _signature_is_functionlike(obj):
|
|
"""Private helper to test if `obj` is a duck type of FunctionType.
|
|
A good example of such objects are functions compiled with
|
|
Cython, which have all attributes that a pure Python function
|
|
would have, but have their code statically compiled.
|
|
"""
|
|
|
|
if not callable(obj) or isclass(obj):
|
|
# All function-like objects are obviously callables,
|
|
# and not classes.
|
|
return False
|
|
|
|
name = getattr(obj, '__name__', None)
|
|
code = getattr(obj, '__code__', None)
|
|
defaults = getattr(obj, '__defaults__', _void) # Important to use _void ...
|
|
kwdefaults = getattr(obj, '__kwdefaults__', _void) # ... and not None here
|
|
annotations = getattr(obj, '__annotations__', None)
|
|
|
|
return (isinstance(code, types.CodeType) and
|
|
isinstance(name, str) and
|
|
(defaults is None or isinstance(defaults, tuple)) and
|
|
(kwdefaults is None or isinstance(kwdefaults, dict)) and
|
|
isinstance(annotations, dict))
|
|
|
|
|
|
def _signature_get_bound_param(spec):
|
|
""" Private helper to get first parameter name from a
|
|
__text_signature__ of a builtin method, which should
|
|
be in the following format: '($param1, ...)'.
|
|
Assumptions are that the first argument won't have
|
|
a default value or an annotation.
|
|
"""
|
|
|
|
assert spec.startswith('($')
|
|
|
|
pos = spec.find(',')
|
|
if pos == -1:
|
|
pos = spec.find(')')
|
|
|
|
cpos = spec.find(':')
|
|
assert cpos == -1 or cpos > pos
|
|
|
|
cpos = spec.find('=')
|
|
assert cpos == -1 or cpos > pos
|
|
|
|
return spec[2:pos]
|
|
|
|
|
|
def _signature_strip_non_python_syntax(signature):
|
|
"""
|
|
Private helper function. Takes a signature in Argument Clinic's
|
|
extended signature format.
|
|
|
|
Returns a tuple of three things:
|
|
* that signature re-rendered in standard Python syntax,
|
|
* the index of the "self" parameter (generally 0), or None if
|
|
the function does not have a "self" parameter, and
|
|
* the index of the last "positional only" parameter,
|
|
or None if the signature has no positional-only parameters.
|
|
"""
|
|
|
|
if not signature:
|
|
return signature, None, None
|
|
|
|
self_parameter = None
|
|
last_positional_only = None
|
|
|
|
lines = [l.encode('ascii') for l in signature.split('\n')]
|
|
generator = iter(lines).__next__
|
|
token_stream = tokenize.tokenize(generator)
|
|
|
|
delayed_comma = False
|
|
skip_next_comma = False
|
|
text = []
|
|
add = text.append
|
|
|
|
current_parameter = 0
|
|
OP = token.OP
|
|
ERRORTOKEN = token.ERRORTOKEN
|
|
|
|
# token stream always starts with ENCODING token, skip it
|
|
t = next(token_stream)
|
|
assert t.type == tokenize.ENCODING
|
|
|
|
for t in token_stream:
|
|
type, string = t.type, t.string
|
|
|
|
if type == OP:
|
|
if string == ',':
|
|
if skip_next_comma:
|
|
skip_next_comma = False
|
|
else:
|
|
assert not delayed_comma
|
|
delayed_comma = True
|
|
current_parameter += 1
|
|
continue
|
|
|
|
if string == '/':
|
|
assert not skip_next_comma
|
|
assert last_positional_only is None
|
|
skip_next_comma = True
|
|
last_positional_only = current_parameter - 1
|
|
continue
|
|
|
|
if (type == ERRORTOKEN) and (string == '$'):
|
|
assert self_parameter is None
|
|
self_parameter = current_parameter
|
|
continue
|
|
|
|
if delayed_comma:
|
|
delayed_comma = False
|
|
if not ((type == OP) and (string == ')')):
|
|
add(', ')
|
|
add(string)
|
|
if (string == ','):
|
|
add(' ')
|
|
clean_signature = ''.join(text)
|
|
return clean_signature, self_parameter, last_positional_only
|
|
|
|
|
|
def _signature_fromstr(cls, obj, s, skip_bound_arg=True):
|
|
"""Private helper to parse content of '__text_signature__'
|
|
and return a Signature based on it.
|
|
"""
|
|
|
|
Parameter = cls._parameter_cls
|
|
|
|
clean_signature, self_parameter, last_positional_only = \
|
|
_signature_strip_non_python_syntax(s)
|
|
|
|
program = "def foo" + clean_signature + ": pass"
|
|
|
|
try:
|
|
module = ast.parse(program)
|
|
except SyntaxError:
|
|
module = None
|
|
|
|
if not isinstance(module, ast.Module):
|
|
raise ValueError("{!r} builtin has invalid signature".format(obj))
|
|
|
|
f = module.body[0]
|
|
|
|
parameters = []
|
|
empty = Parameter.empty
|
|
invalid = object()
|
|
|
|
module = None
|
|
module_dict = {}
|
|
module_name = getattr(obj, '__module__', None)
|
|
if module_name:
|
|
module = sys.modules.get(module_name, None)
|
|
if module:
|
|
module_dict = module.__dict__
|
|
sys_module_dict = sys.modules
|
|
|
|
def parse_name(node):
|
|
assert isinstance(node, ast.arg)
|
|
if node.annotation != None:
|
|
raise ValueError("Annotations are not currently supported")
|
|
return node.arg
|
|
|
|
def wrap_value(s):
|
|
try:
|
|
value = eval(s, module_dict)
|
|
except NameError:
|
|
try:
|
|
value = eval(s, sys_module_dict)
|
|
except NameError:
|
|
raise RuntimeError()
|
|
|
|
if isinstance(value, str):
|
|
return ast.Str(value)
|
|
if isinstance(value, (int, float)):
|
|
return ast.Num(value)
|
|
if isinstance(value, bytes):
|
|
return ast.Bytes(value)
|
|
if value in (True, False, None):
|
|
return ast.NameConstant(value)
|
|
raise RuntimeError()
|
|
|
|
class RewriteSymbolics(ast.NodeTransformer):
|
|
def visit_Attribute(self, node):
|
|
a = []
|
|
n = node
|
|
while isinstance(n, ast.Attribute):
|
|
a.append(n.attr)
|
|
n = n.value
|
|
if not isinstance(n, ast.Name):
|
|
raise RuntimeError()
|
|
a.append(n.id)
|
|
value = ".".join(reversed(a))
|
|
return wrap_value(value)
|
|
|
|
def visit_Name(self, node):
|
|
if not isinstance(node.ctx, ast.Load):
|
|
raise ValueError()
|
|
return wrap_value(node.id)
|
|
|
|
def p(name_node, default_node, default=empty):
|
|
name = parse_name(name_node)
|
|
if name is invalid:
|
|
return None
|
|
if default_node and default_node is not _empty:
|
|
try:
|
|
default_node = RewriteSymbolics().visit(default_node)
|
|
o = ast.literal_eval(default_node)
|
|
except ValueError:
|
|
o = invalid
|
|
if o is invalid:
|
|
return None
|
|
default = o if o is not invalid else default
|
|
parameters.append(Parameter(name, kind, default=default, annotation=empty))
|
|
|
|
# non-keyword-only parameters
|
|
args = reversed(f.args.args)
|
|
defaults = reversed(f.args.defaults)
|
|
iter = itertools.zip_longest(args, defaults, fillvalue=None)
|
|
if last_positional_only is not None:
|
|
kind = Parameter.POSITIONAL_ONLY
|
|
else:
|
|
kind = Parameter.POSITIONAL_OR_KEYWORD
|
|
for i, (name, default) in enumerate(reversed(list(iter))):
|
|
p(name, default)
|
|
if i == last_positional_only:
|
|
kind = Parameter.POSITIONAL_OR_KEYWORD
|
|
|
|
# *args
|
|
if f.args.vararg:
|
|
kind = Parameter.VAR_POSITIONAL
|
|
p(f.args.vararg, empty)
|
|
|
|
# keyword-only arguments
|
|
kind = Parameter.KEYWORD_ONLY
|
|
for name, default in zip(f.args.kwonlyargs, f.args.kw_defaults):
|
|
p(name, default)
|
|
|
|
# **kwargs
|
|
if f.args.kwarg:
|
|
kind = Parameter.VAR_KEYWORD
|
|
p(f.args.kwarg, empty)
|
|
|
|
if self_parameter is not None:
|
|
# Possibly strip the bound argument:
|
|
# - We *always* strip first bound argument if
|
|
# it is a module.
|
|
# - We don't strip first bound argument if
|
|
# skip_bound_arg is False.
|
|
assert parameters
|
|
_self = getattr(obj, '__self__', None)
|
|
self_isbound = _self is not None
|
|
self_ismodule = ismodule(_self)
|
|
if self_isbound and (self_ismodule or skip_bound_arg):
|
|
parameters.pop(0)
|
|
else:
|
|
# for builtins, self parameter is always positional-only!
|
|
p = parameters[0].replace(kind=Parameter.POSITIONAL_ONLY)
|
|
parameters[0] = p
|
|
|
|
return cls(parameters, return_annotation=cls.empty)
|
|
|
|
|
|
def _signature_from_builtin(cls, func, skip_bound_arg=True):
|
|
"""Private helper function to get signature for
|
|
builtin callables.
|
|
"""
|
|
|
|
if not _signature_is_builtin(func):
|
|
raise TypeError("{!r} is not a Python builtin "
|
|
"function".format(func))
|
|
|
|
s = getattr(func, "__text_signature__", None)
|
|
if not s:
|
|
raise ValueError("no signature found for builtin {!r}".format(func))
|
|
|
|
return _signature_fromstr(cls, func, s, skip_bound_arg)
|
|
|
|
|
|
def _signature_from_function(cls, func):
|
|
"""Private helper: constructs Signature for the given python function."""
|
|
|
|
is_duck_function = False
|
|
if not isfunction(func):
|
|
if _signature_is_functionlike(func):
|
|
is_duck_function = True
|
|
else:
|
|
# If it's not a pure Python function, and not a duck type
|
|
# of pure function:
|
|
raise TypeError('{!r} is not a Python function'.format(func))
|
|
|
|
Parameter = cls._parameter_cls
|
|
|
|
# Parameter information.
|
|
func_code = func.__code__
|
|
pos_count = func_code.co_argcount
|
|
arg_names = func_code.co_varnames
|
|
positional = tuple(arg_names[:pos_count])
|
|
keyword_only_count = func_code.co_kwonlyargcount
|
|
keyword_only = arg_names[pos_count:(pos_count + keyword_only_count)]
|
|
annotations = func.__annotations__
|
|
defaults = func.__defaults__
|
|
kwdefaults = func.__kwdefaults__
|
|
|
|
if defaults:
|
|
pos_default_count = len(defaults)
|
|
else:
|
|
pos_default_count = 0
|
|
|
|
parameters = []
|
|
|
|
# Non-keyword-only parameters w/o defaults.
|
|
non_default_count = pos_count - pos_default_count
|
|
for name in positional[:non_default_count]:
|
|
annotation = annotations.get(name, _empty)
|
|
parameters.append(Parameter(name, annotation=annotation,
|
|
kind=_POSITIONAL_OR_KEYWORD))
|
|
|
|
# ... w/ defaults.
|
|
for offset, name in enumerate(positional[non_default_count:]):
|
|
annotation = annotations.get(name, _empty)
|
|
parameters.append(Parameter(name, annotation=annotation,
|
|
kind=_POSITIONAL_OR_KEYWORD,
|
|
default=defaults[offset]))
|
|
|
|
# *args
|
|
if func_code.co_flags & CO_VARARGS:
|
|
name = arg_names[pos_count + keyword_only_count]
|
|
annotation = annotations.get(name, _empty)
|
|
parameters.append(Parameter(name, annotation=annotation,
|
|
kind=_VAR_POSITIONAL))
|
|
|
|
# Keyword-only parameters.
|
|
for name in keyword_only:
|
|
default = _empty
|
|
if kwdefaults is not None:
|
|
default = kwdefaults.get(name, _empty)
|
|
|
|
annotation = annotations.get(name, _empty)
|
|
parameters.append(Parameter(name, annotation=annotation,
|
|
kind=_KEYWORD_ONLY,
|
|
default=default))
|
|
# **kwargs
|
|
if func_code.co_flags & CO_VARKEYWORDS:
|
|
index = pos_count + keyword_only_count
|
|
if func_code.co_flags & CO_VARARGS:
|
|
index += 1
|
|
|
|
name = arg_names[index]
|
|
annotation = annotations.get(name, _empty)
|
|
parameters.append(Parameter(name, annotation=annotation,
|
|
kind=_VAR_KEYWORD))
|
|
|
|
# Is 'func' is a pure Python function - don't validate the
|
|
# parameters list (for correct order and defaults), it should be OK.
|
|
return cls(parameters,
|
|
return_annotation=annotations.get('return', _empty),
|
|
__validate_parameters__=is_duck_function)
|
|
|
|
|
|
def _signature_from_callable(obj, *,
|
|
follow_wrapper_chains=True,
|
|
skip_bound_arg=True,
|
|
sigcls):
|
|
|
|
"""Private helper function to get signature for arbitrary
|
|
callable objects.
|
|
"""
|
|
|
|
if not callable(obj):
|
|
raise TypeError('{!r} is not a callable object'.format(obj))
|
|
|
|
if isinstance(obj, types.MethodType):
|
|
# In this case we skip the first parameter of the underlying
|
|
# function (usually `self` or `cls`).
|
|
sig = _signature_from_callable(
|
|
obj.__func__,
|
|
follow_wrapper_chains=follow_wrapper_chains,
|
|
skip_bound_arg=skip_bound_arg,
|
|
sigcls=sigcls)
|
|
|
|
if skip_bound_arg:
|
|
return _signature_bound_method(sig)
|
|
else:
|
|
return sig
|
|
|
|
# Was this function wrapped by a decorator?
|
|
if follow_wrapper_chains:
|
|
obj = unwrap(obj, stop=(lambda f: hasattr(f, "__signature__")))
|
|
if isinstance(obj, types.MethodType):
|
|
# If the unwrapped object is a *method*, we might want to
|
|
# skip its first parameter (self).
|
|
# See test_signature_wrapped_bound_method for details.
|
|
return _signature_from_callable(
|
|
obj,
|
|
follow_wrapper_chains=follow_wrapper_chains,
|
|
skip_bound_arg=skip_bound_arg,
|
|
sigcls=sigcls)
|
|
|
|
try:
|
|
sig = obj.__signature__
|
|
except AttributeError:
|
|
pass
|
|
else:
|
|
if sig is not None:
|
|
if not isinstance(sig, Signature):
|
|
raise TypeError(
|
|
'unexpected object {!r} in __signature__ '
|
|
'attribute'.format(sig))
|
|
return sig
|
|
|
|
try:
|
|
partialmethod = obj._partialmethod
|
|
except AttributeError:
|
|
pass
|
|
else:
|
|
if isinstance(partialmethod, functools.partialmethod):
|
|
# Unbound partialmethod (see functools.partialmethod)
|
|
# This means, that we need to calculate the signature
|
|
# as if it's a regular partial object, but taking into
|
|
# account that the first positional argument
|
|
# (usually `self`, or `cls`) will not be passed
|
|
# automatically (as for boundmethods)
|
|
|
|
wrapped_sig = _signature_from_callable(
|
|
partialmethod.func,
|
|
follow_wrapper_chains=follow_wrapper_chains,
|
|
skip_bound_arg=skip_bound_arg,
|
|
sigcls=sigcls)
|
|
|
|
sig = _signature_get_partial(wrapped_sig, partialmethod, (None,))
|
|
first_wrapped_param = tuple(wrapped_sig.parameters.values())[0]
|
|
if first_wrapped_param.kind is Parameter.VAR_POSITIONAL:
|
|
# First argument of the wrapped callable is `*args`, as in
|
|
# `partialmethod(lambda *args)`.
|
|
return sig
|
|
else:
|
|
sig_params = tuple(sig.parameters.values())
|
|
assert first_wrapped_param is not sig_params[0]
|
|
new_params = (first_wrapped_param,) + sig_params
|
|
return sig.replace(parameters=new_params)
|
|
|
|
if isfunction(obj) or _signature_is_functionlike(obj):
|
|
# If it's a pure Python function, or an object that is duck type
|
|
# of a Python function (Cython functions, for instance), then:
|
|
return _signature_from_function(sigcls, obj)
|
|
|
|
if _signature_is_builtin(obj):
|
|
return _signature_from_builtin(sigcls, obj,
|
|
skip_bound_arg=skip_bound_arg)
|
|
|
|
if isinstance(obj, functools.partial):
|
|
wrapped_sig = _signature_from_callable(
|
|
obj.func,
|
|
follow_wrapper_chains=follow_wrapper_chains,
|
|
skip_bound_arg=skip_bound_arg,
|
|
sigcls=sigcls)
|
|
return _signature_get_partial(wrapped_sig, obj)
|
|
|
|
sig = None
|
|
if isinstance(obj, type):
|
|
# obj is a class or a metaclass
|
|
|
|
# First, let's see if it has an overloaded __call__ defined
|
|
# in its metaclass
|
|
call = _signature_get_user_defined_method(type(obj), '__call__')
|
|
if call is not None:
|
|
sig = _signature_from_callable(
|
|
call,
|
|
follow_wrapper_chains=follow_wrapper_chains,
|
|
skip_bound_arg=skip_bound_arg,
|
|
sigcls=sigcls)
|
|
else:
|
|
# Now we check if the 'obj' class has a '__new__' method
|
|
new = _signature_get_user_defined_method(obj, '__new__')
|
|
if new is not None:
|
|
sig = _signature_from_callable(
|
|
new,
|
|
follow_wrapper_chains=follow_wrapper_chains,
|
|
skip_bound_arg=skip_bound_arg,
|
|
sigcls=sigcls)
|
|
else:
|
|
# Finally, we should have at least __init__ implemented
|
|
init = _signature_get_user_defined_method(obj, '__init__')
|
|
if init is not None:
|
|
sig = _signature_from_callable(
|
|
init,
|
|
follow_wrapper_chains=follow_wrapper_chains,
|
|
skip_bound_arg=skip_bound_arg,
|
|
sigcls=sigcls)
|
|
|
|
if sig is None:
|
|
# At this point we know, that `obj` is a class, with no user-
|
|
# defined '__init__', '__new__', or class-level '__call__'
|
|
|
|
for base in obj.__mro__[:-1]:
|
|
# Since '__text_signature__' is implemented as a
|
|
# descriptor that extracts text signature from the
|
|
# class docstring, if 'obj' is derived from a builtin
|
|
# class, its own '__text_signature__' may be 'None'.
|
|
# Therefore, we go through the MRO (except the last
|
|
# class in there, which is 'object') to find the first
|
|
# class with non-empty text signature.
|
|
try:
|
|
text_sig = base.__text_signature__
|
|
except AttributeError:
|
|
pass
|
|
else:
|
|
if text_sig:
|
|
# If 'obj' class has a __text_signature__ attribute:
|
|
# return a signature based on it
|
|
return _signature_fromstr(sigcls, obj, text_sig)
|
|
|
|
# No '__text_signature__' was found for the 'obj' class.
|
|
# Last option is to check if its '__init__' is
|
|
# object.__init__ or type.__init__.
|
|
if type not in obj.__mro__:
|
|
# We have a class (not metaclass), but no user-defined
|
|
# __init__ or __new__ for it
|
|
if (obj.__init__ is object.__init__ and
|
|
obj.__new__ is object.__new__):
|
|
# Return a signature of 'object' builtin.
|
|
return signature(object)
|
|
else:
|
|
raise ValueError(
|
|
'no signature found for builtin type {!r}'.format(obj))
|
|
|
|
elif not isinstance(obj, _NonUserDefinedCallables):
|
|
# An object with __call__
|
|
# We also check that the 'obj' is not an instance of
|
|
# _WrapperDescriptor or _MethodWrapper to avoid
|
|
# infinite recursion (and even potential segfault)
|
|
call = _signature_get_user_defined_method(type(obj), '__call__')
|
|
if call is not None:
|
|
try:
|
|
sig = _signature_from_callable(
|
|
call,
|
|
follow_wrapper_chains=follow_wrapper_chains,
|
|
skip_bound_arg=skip_bound_arg,
|
|
sigcls=sigcls)
|
|
except ValueError as ex:
|
|
msg = 'no signature found for {!r}'.format(obj)
|
|
raise ValueError(msg) from ex
|
|
|
|
if sig is not None:
|
|
# For classes and objects we skip the first parameter of their
|
|
# __call__, __new__, or __init__ methods
|
|
if skip_bound_arg:
|
|
return _signature_bound_method(sig)
|
|
else:
|
|
return sig
|
|
|
|
if isinstance(obj, types.BuiltinFunctionType):
|
|
# Raise a nicer error message for builtins
|
|
msg = 'no signature found for builtin function {!r}'.format(obj)
|
|
raise ValueError(msg)
|
|
|
|
raise ValueError('callable {!r} is not supported by signature'.format(obj))
|
|
|
|
|
|
class _void:
|
|
"""A private marker - used in Parameter & Signature."""
|
|
|
|
|
|
class _empty:
|
|
"""Marker object for Signature.empty and Parameter.empty."""
|
|
|
|
|
|
class _ParameterKind(enum.IntEnum):
|
|
POSITIONAL_ONLY = 0
|
|
POSITIONAL_OR_KEYWORD = 1
|
|
VAR_POSITIONAL = 2
|
|
KEYWORD_ONLY = 3
|
|
VAR_KEYWORD = 4
|
|
|
|
def __str__(self):
|
|
return self._name_
|
|
|
|
|
|
_POSITIONAL_ONLY = _ParameterKind.POSITIONAL_ONLY
|
|
_POSITIONAL_OR_KEYWORD = _ParameterKind.POSITIONAL_OR_KEYWORD
|
|
_VAR_POSITIONAL = _ParameterKind.VAR_POSITIONAL
|
|
_KEYWORD_ONLY = _ParameterKind.KEYWORD_ONLY
|
|
_VAR_KEYWORD = _ParameterKind.VAR_KEYWORD
|
|
|
|
|
|
class Parameter:
|
|
"""Represents a parameter in a function signature.
|
|
|
|
Has the following public attributes:
|
|
|
|
* name : str
|
|
The name of the parameter as a string.
|
|
* default : object
|
|
The default value for the parameter if specified. If the
|
|
parameter has no default value, this attribute is set to
|
|
`Parameter.empty`.
|
|
* annotation
|
|
The annotation for the parameter if specified. If the
|
|
parameter has no annotation, this attribute is set to
|
|
`Parameter.empty`.
|
|
* kind : str
|
|
Describes how argument values are bound to the parameter.
|
|
Possible values: `Parameter.POSITIONAL_ONLY`,
|
|
`Parameter.POSITIONAL_OR_KEYWORD`, `Parameter.VAR_POSITIONAL`,
|
|
`Parameter.KEYWORD_ONLY`, `Parameter.VAR_KEYWORD`.
|
|
"""
|
|
|
|
__slots__ = ('_name', '_kind', '_default', '_annotation')
|
|
|
|
POSITIONAL_ONLY = _POSITIONAL_ONLY
|
|
POSITIONAL_OR_KEYWORD = _POSITIONAL_OR_KEYWORD
|
|
VAR_POSITIONAL = _VAR_POSITIONAL
|
|
KEYWORD_ONLY = _KEYWORD_ONLY
|
|
VAR_KEYWORD = _VAR_KEYWORD
|
|
|
|
empty = _empty
|
|
|
|
def __init__(self, name, kind, *, default=_empty, annotation=_empty):
|
|
|
|
if kind not in (_POSITIONAL_ONLY, _POSITIONAL_OR_KEYWORD,
|
|
_VAR_POSITIONAL, _KEYWORD_ONLY, _VAR_KEYWORD):
|
|
raise ValueError("invalid value for 'Parameter.kind' attribute")
|
|
self._kind = kind
|
|
|
|
if default is not _empty:
|
|
if kind in (_VAR_POSITIONAL, _VAR_KEYWORD):
|
|
msg = '{} parameters cannot have default values'.format(kind)
|
|
raise ValueError(msg)
|
|
self._default = default
|
|
self._annotation = annotation
|
|
|
|
if name is _empty:
|
|
raise ValueError('name is a required attribute for Parameter')
|
|
|
|
if not isinstance(name, str):
|
|
raise TypeError("name must be a str, not a {!r}".format(name))
|
|
|
|
if name[0] == '.' and name[1:].isdigit():
|
|
# These are implicit arguments generated by comprehensions. In
|
|
# order to provide a friendlier interface to users, we recast
|
|
# their name as "implicitN" and treat them as positional-only.
|
|
# See issue 19611.
|
|
if kind != _POSITIONAL_OR_KEYWORD:
|
|
raise ValueError(
|
|
'implicit arguments must be passed in as {}'.format(
|
|
_POSITIONAL_OR_KEYWORD
|
|
)
|
|
)
|
|
self._kind = _POSITIONAL_ONLY
|
|
name = 'implicit{}'.format(name[1:])
|
|
|
|
if not name.isidentifier():
|
|
raise ValueError('{!r} is not a valid parameter name'.format(name))
|
|
|
|
self._name = name
|
|
|
|
def __reduce__(self):
|
|
return (type(self),
|
|
(self._name, self._kind),
|
|
{'_default': self._default,
|
|
'_annotation': self._annotation})
|
|
|
|
def __setstate__(self, state):
|
|
self._default = state['_default']
|
|
self._annotation = state['_annotation']
|
|
|
|
@property
|
|
def name(self):
|
|
return self._name
|
|
|
|
@property
|
|
def default(self):
|
|
return self._default
|
|
|
|
@property
|
|
def annotation(self):
|
|
return self._annotation
|
|
|
|
@property
|
|
def kind(self):
|
|
return self._kind
|
|
|
|
def replace(self, *, name=_void, kind=_void,
|
|
annotation=_void, default=_void):
|
|
"""Creates a customized copy of the Parameter."""
|
|
|
|
if name is _void:
|
|
name = self._name
|
|
|
|
if kind is _void:
|
|
kind = self._kind
|
|
|
|
if annotation is _void:
|
|
annotation = self._annotation
|
|
|
|
if default is _void:
|
|
default = self._default
|
|
|
|
return type(self)(name, kind, default=default, annotation=annotation)
|
|
|
|
def __str__(self):
|
|
kind = self.kind
|
|
formatted = self._name
|
|
|
|
# Add annotation and default value
|
|
if self._annotation is not _empty:
|
|
formatted = '{}:{}'.format(formatted,
|
|
formatannotation(self._annotation))
|
|
|
|
if self._default is not _empty:
|
|
formatted = '{}={}'.format(formatted, repr(self._default))
|
|
|
|
if kind == _VAR_POSITIONAL:
|
|
formatted = '*' + formatted
|
|
elif kind == _VAR_KEYWORD:
|
|
formatted = '**' + formatted
|
|
|
|
return formatted
|
|
|
|
def __repr__(self):
|
|
return '<{} "{}">'.format(self.__class__.__name__, self)
|
|
|
|
def __hash__(self):
|
|
return hash((self.name, self.kind, self.annotation, self.default))
|
|
|
|
def __eq__(self, other):
|
|
if self is other:
|
|
return True
|
|
if not isinstance(other, Parameter):
|
|
return NotImplemented
|
|
return (self._name == other._name and
|
|
self._kind == other._kind and
|
|
self._default == other._default and
|
|
self._annotation == other._annotation)
|
|
|
|
|
|
class BoundArguments:
|
|
"""Result of `Signature.bind` call. Holds the mapping of arguments
|
|
to the function's parameters.
|
|
|
|
Has the following public attributes:
|
|
|
|
* arguments : OrderedDict
|
|
An ordered mutable mapping of parameters' names to arguments' values.
|
|
Does not contain arguments' default values.
|
|
* signature : Signature
|
|
The Signature object that created this instance.
|
|
* args : tuple
|
|
Tuple of positional arguments values.
|
|
* kwargs : dict
|
|
Dict of keyword arguments values.
|
|
"""
|
|
|
|
__slots__ = ('arguments', '_signature', '__weakref__')
|
|
|
|
def __init__(self, signature, arguments):
|
|
self.arguments = arguments
|
|
self._signature = signature
|
|
|
|
@property
|
|
def signature(self):
|
|
return self._signature
|
|
|
|
@property
|
|
def args(self):
|
|
args = []
|
|
for param_name, param in self._signature.parameters.items():
|
|
if param.kind in (_VAR_KEYWORD, _KEYWORD_ONLY):
|
|
break
|
|
|
|
try:
|
|
arg = self.arguments[param_name]
|
|
except KeyError:
|
|
# We're done here. Other arguments
|
|
# will be mapped in 'BoundArguments.kwargs'
|
|
break
|
|
else:
|
|
if param.kind == _VAR_POSITIONAL:
|
|
# *args
|
|
args.extend(arg)
|
|
else:
|
|
# plain argument
|
|
args.append(arg)
|
|
|
|
return tuple(args)
|
|
|
|
@property
|
|
def kwargs(self):
|
|
kwargs = {}
|
|
kwargs_started = False
|
|
for param_name, param in self._signature.parameters.items():
|
|
if not kwargs_started:
|
|
if param.kind in (_VAR_KEYWORD, _KEYWORD_ONLY):
|
|
kwargs_started = True
|
|
else:
|
|
if param_name not in self.arguments:
|
|
kwargs_started = True
|
|
continue
|
|
|
|
if not kwargs_started:
|
|
continue
|
|
|
|
try:
|
|
arg = self.arguments[param_name]
|
|
except KeyError:
|
|
pass
|
|
else:
|
|
if param.kind == _VAR_KEYWORD:
|
|
# **kwargs
|
|
kwargs.update(arg)
|
|
else:
|
|
# plain keyword argument
|
|
kwargs[param_name] = arg
|
|
|
|
return kwargs
|
|
|
|
def apply_defaults(self):
|
|
"""Set default values for missing arguments.
|
|
|
|
For variable-positional arguments (*args) the default is an
|
|
empty tuple.
|
|
|
|
For variable-keyword arguments (**kwargs) the default is an
|
|
empty dict.
|
|
"""
|
|
arguments = self.arguments
|
|
new_arguments = []
|
|
for name, param in self._signature.parameters.items():
|
|
try:
|
|
new_arguments.append((name, arguments[name]))
|
|
except KeyError:
|
|
if param.default is not _empty:
|
|
val = param.default
|
|
elif param.kind is _VAR_POSITIONAL:
|
|
val = ()
|
|
elif param.kind is _VAR_KEYWORD:
|
|
val = {}
|
|
else:
|
|
# This BoundArguments was likely produced by
|
|
# Signature.bind_partial().
|
|
continue
|
|
new_arguments.append((name, val))
|
|
self.arguments = OrderedDict(new_arguments)
|
|
|
|
def __eq__(self, other):
|
|
if self is other:
|
|
return True
|
|
if not isinstance(other, BoundArguments):
|
|
return NotImplemented
|
|
return (self.signature == other.signature and
|
|
self.arguments == other.arguments)
|
|
|
|
def __setstate__(self, state):
|
|
self._signature = state['_signature']
|
|
self.arguments = state['arguments']
|
|
|
|
def __getstate__(self):
|
|
return {'_signature': self._signature, 'arguments': self.arguments}
|
|
|
|
def __repr__(self):
|
|
args = []
|
|
for arg, value in self.arguments.items():
|
|
args.append('{}={!r}'.format(arg, value))
|
|
return '<{} ({})>'.format(self.__class__.__name__, ', '.join(args))
|
|
|
|
|
|
class Signature:
|
|
"""A Signature object represents the overall signature of a function.
|
|
It stores a Parameter object for each parameter accepted by the
|
|
function, as well as information specific to the function itself.
|
|
|
|
A Signature object has the following public attributes and methods:
|
|
|
|
* parameters : OrderedDict
|
|
An ordered mapping of parameters' names to the corresponding
|
|
Parameter objects (keyword-only arguments are in the same order
|
|
as listed in `code.co_varnames`).
|
|
* return_annotation : object
|
|
The annotation for the return type of the function if specified.
|
|
If the function has no annotation for its return type, this
|
|
attribute is set to `Signature.empty`.
|
|
* bind(*args, **kwargs) -> BoundArguments
|
|
Creates a mapping from positional and keyword arguments to
|
|
parameters.
|
|
* bind_partial(*args, **kwargs) -> BoundArguments
|
|
Creates a partial mapping from positional and keyword arguments
|
|
to parameters (simulating 'functools.partial' behavior.)
|
|
"""
|
|
|
|
__slots__ = ('_return_annotation', '_parameters')
|
|
|
|
_parameter_cls = Parameter
|
|
_bound_arguments_cls = BoundArguments
|
|
|
|
empty = _empty
|
|
|
|
def __init__(self, parameters=None, *, return_annotation=_empty,
|
|
__validate_parameters__=True):
|
|
"""Constructs Signature from the given list of Parameter
|
|
objects and 'return_annotation'. All arguments are optional.
|
|
"""
|
|
|
|
if parameters is None:
|
|
params = OrderedDict()
|
|
else:
|
|
if __validate_parameters__:
|
|
params = OrderedDict()
|
|
top_kind = _POSITIONAL_ONLY
|
|
kind_defaults = False
|
|
|
|
for idx, param in enumerate(parameters):
|
|
kind = param.kind
|
|
name = param.name
|
|
|
|
if kind < top_kind:
|
|
msg = 'wrong parameter order: {!r} before {!r}'
|
|
msg = msg.format(top_kind, kind)
|
|
raise ValueError(msg)
|
|
elif kind > top_kind:
|
|
kind_defaults = False
|
|
top_kind = kind
|
|
|
|
if kind in (_POSITIONAL_ONLY, _POSITIONAL_OR_KEYWORD):
|
|
if param.default is _empty:
|
|
if kind_defaults:
|
|
# No default for this parameter, but the
|
|
# previous parameter of the same kind had
|
|
# a default
|
|
msg = 'non-default argument follows default ' \
|
|
'argument'
|
|
raise ValueError(msg)
|
|
else:
|
|
# There is a default for this parameter.
|
|
kind_defaults = True
|
|
|
|
if name in params:
|
|
msg = 'duplicate parameter name: {!r}'.format(name)
|
|
raise ValueError(msg)
|
|
|
|
params[name] = param
|
|
else:
|
|
params = OrderedDict(((param.name, param)
|
|
for param in parameters))
|
|
|
|
self._parameters = types.MappingProxyType(params)
|
|
self._return_annotation = return_annotation
|
|
|
|
@classmethod
|
|
def from_function(cls, func):
|
|
"""Constructs Signature for the given python function."""
|
|
|
|
warnings.warn("inspect.Signature.from_function() is deprecated, "
|
|
"use Signature.from_callable()",
|
|
DeprecationWarning, stacklevel=2)
|
|
return _signature_from_function(cls, func)
|
|
|
|
@classmethod
|
|
def from_builtin(cls, func):
|
|
"""Constructs Signature for the given builtin function."""
|
|
|
|
warnings.warn("inspect.Signature.from_builtin() is deprecated, "
|
|
"use Signature.from_callable()",
|
|
DeprecationWarning, stacklevel=2)
|
|
return _signature_from_builtin(cls, func)
|
|
|
|
@classmethod
|
|
def from_callable(cls, obj, *, follow_wrapped=True):
|
|
"""Constructs Signature for the given callable object."""
|
|
return _signature_from_callable(obj, sigcls=cls,
|
|
follow_wrapper_chains=follow_wrapped)
|
|
|
|
@property
|
|
def parameters(self):
|
|
return self._parameters
|
|
|
|
@property
|
|
def return_annotation(self):
|
|
return self._return_annotation
|
|
|
|
def replace(self, *, parameters=_void, return_annotation=_void):
|
|
"""Creates a customized copy of the Signature.
|
|
Pass 'parameters' and/or 'return_annotation' arguments
|
|
to override them in the new copy.
|
|
"""
|
|
|
|
if parameters is _void:
|
|
parameters = self.parameters.values()
|
|
|
|
if return_annotation is _void:
|
|
return_annotation = self._return_annotation
|
|
|
|
return type(self)(parameters,
|
|
return_annotation=return_annotation)
|
|
|
|
def _hash_basis(self):
|
|
params = tuple(param for param in self.parameters.values()
|
|
if param.kind != _KEYWORD_ONLY)
|
|
|
|
kwo_params = {param.name: param for param in self.parameters.values()
|
|
if param.kind == _KEYWORD_ONLY}
|
|
|
|
return params, kwo_params, self.return_annotation
|
|
|
|
def __hash__(self):
|
|
params, kwo_params, return_annotation = self._hash_basis()
|
|
kwo_params = frozenset(kwo_params.values())
|
|
return hash((params, kwo_params, return_annotation))
|
|
|
|
def __eq__(self, other):
|
|
if self is other:
|
|
return True
|
|
if not isinstance(other, Signature):
|
|
return NotImplemented
|
|
return self._hash_basis() == other._hash_basis()
|
|
|
|
def _bind(self, args, kwargs, *, partial=False):
|
|
"""Private method. Don't use directly."""
|
|
|
|
arguments = OrderedDict()
|
|
|
|
parameters = iter(self.parameters.values())
|
|
parameters_ex = ()
|
|
arg_vals = iter(args)
|
|
|
|
while True:
|
|
# Let's iterate through the positional arguments and corresponding
|
|
# parameters
|
|
try:
|
|
arg_val = next(arg_vals)
|
|
except StopIteration:
|
|
# No more positional arguments
|
|
try:
|
|
param = next(parameters)
|
|
except StopIteration:
|
|
# No more parameters. That's it. Just need to check that
|
|
# we have no `kwargs` after this while loop
|
|
break
|
|
else:
|
|
if param.kind == _VAR_POSITIONAL:
|
|
# That's OK, just empty *args. Let's start parsing
|
|
# kwargs
|
|
break
|
|
elif param.name in kwargs:
|
|
if param.kind == _POSITIONAL_ONLY:
|
|
msg = '{arg!r} parameter is positional only, ' \
|
|
'but was passed as a keyword'
|
|
msg = msg.format(arg=param.name)
|
|
raise TypeError(msg) from None
|
|
parameters_ex = (param,)
|
|
break
|
|
elif (param.kind == _VAR_KEYWORD or
|
|
param.default is not _empty):
|
|
# That's fine too - we have a default value for this
|
|
# parameter. So, lets start parsing `kwargs`, starting
|
|
# with the current parameter
|
|
parameters_ex = (param,)
|
|
break
|
|
else:
|
|
# No default, not VAR_KEYWORD, not VAR_POSITIONAL,
|
|
# not in `kwargs`
|
|
if partial:
|
|
parameters_ex = (param,)
|
|
break
|
|
else:
|
|
msg = 'missing a required argument: {arg!r}'
|
|
msg = msg.format(arg=param.name)
|
|
raise TypeError(msg) from None
|
|
else:
|
|
# We have a positional argument to process
|
|
try:
|
|
param = next(parameters)
|
|
except StopIteration:
|
|
raise TypeError('too many positional arguments') from None
|
|
else:
|
|
if param.kind in (_VAR_KEYWORD, _KEYWORD_ONLY):
|
|
# Looks like we have no parameter for this positional
|
|
# argument
|
|
raise TypeError(
|
|
'too many positional arguments') from None
|
|
|
|
if param.kind == _VAR_POSITIONAL:
|
|
# We have an '*args'-like argument, let's fill it with
|
|
# all positional arguments we have left and move on to
|
|
# the next phase
|
|
values = [arg_val]
|
|
values.extend(arg_vals)
|
|
arguments[param.name] = tuple(values)
|
|
break
|
|
|
|
if param.name in kwargs:
|
|
raise TypeError(
|
|
'multiple values for argument {arg!r}'.format(
|
|
arg=param.name)) from None
|
|
|
|
arguments[param.name] = arg_val
|
|
|
|
# Now, we iterate through the remaining parameters to process
|
|
# keyword arguments
|
|
kwargs_param = None
|
|
for param in itertools.chain(parameters_ex, parameters):
|
|
if param.kind == _VAR_KEYWORD:
|
|
# Memorize that we have a '**kwargs'-like parameter
|
|
kwargs_param = param
|
|
continue
|
|
|
|
if param.kind == _VAR_POSITIONAL:
|
|
# Named arguments don't refer to '*args'-like parameters.
|
|
# We only arrive here if the positional arguments ended
|
|
# before reaching the last parameter before *args.
|
|
continue
|
|
|
|
param_name = param.name
|
|
try:
|
|
arg_val = kwargs.pop(param_name)
|
|
except KeyError:
|
|
# We have no value for this parameter. It's fine though,
|
|
# if it has a default value, or it is an '*args'-like
|
|
# parameter, left alone by the processing of positional
|
|
# arguments.
|
|
if (not partial and param.kind != _VAR_POSITIONAL and
|
|
param.default is _empty):
|
|
raise TypeError('missing a required argument: {arg!r}'. \
|
|
format(arg=param_name)) from None
|
|
|
|
else:
|
|
if param.kind == _POSITIONAL_ONLY:
|
|
# This should never happen in case of a properly built
|
|
# Signature object (but let's have this check here
|
|
# to ensure correct behaviour just in case)
|
|
raise TypeError('{arg!r} parameter is positional only, '
|
|
'but was passed as a keyword'. \
|
|
format(arg=param.name))
|
|
|
|
arguments[param_name] = arg_val
|
|
|
|
if kwargs:
|
|
if kwargs_param is not None:
|
|
# Process our '**kwargs'-like parameter
|
|
arguments[kwargs_param.name] = kwargs
|
|
else:
|
|
raise TypeError(
|
|
'got an unexpected keyword argument {arg!r}'.format(
|
|
arg=next(iter(kwargs))))
|
|
|
|
return self._bound_arguments_cls(self, arguments)
|
|
|
|
def bind(*args, **kwargs):
|
|
"""Get a BoundArguments object, that maps the passed `args`
|
|
and `kwargs` to the function's signature. Raises `TypeError`
|
|
if the passed arguments can not be bound.
|
|
"""
|
|
return args[0]._bind(args[1:], kwargs)
|
|
|
|
def bind_partial(*args, **kwargs):
|
|
"""Get a BoundArguments object, that partially maps the
|
|
passed `args` and `kwargs` to the function's signature.
|
|
Raises `TypeError` if the passed arguments can not be bound.
|
|
"""
|
|
return args[0]._bind(args[1:], kwargs, partial=True)
|
|
|
|
def __reduce__(self):
|
|
return (type(self),
|
|
(tuple(self._parameters.values()),),
|
|
{'_return_annotation': self._return_annotation})
|
|
|
|
def __setstate__(self, state):
|
|
self._return_annotation = state['_return_annotation']
|
|
|
|
def __repr__(self):
|
|
return '<{} {}>'.format(self.__class__.__name__, self)
|
|
|
|
def __str__(self):
|
|
result = []
|
|
render_pos_only_separator = False
|
|
render_kw_only_separator = True
|
|
for param in self.parameters.values():
|
|
formatted = str(param)
|
|
|
|
kind = param.kind
|
|
|
|
if kind == _POSITIONAL_ONLY:
|
|
render_pos_only_separator = True
|
|
elif render_pos_only_separator:
|
|
# It's not a positional-only parameter, and the flag
|
|
# is set to 'True' (there were pos-only params before.)
|
|
result.append('/')
|
|
render_pos_only_separator = False
|
|
|
|
if kind == _VAR_POSITIONAL:
|
|
# OK, we have an '*args'-like parameter, so we won't need
|
|
# a '*' to separate keyword-only arguments
|
|
render_kw_only_separator = False
|
|
elif kind == _KEYWORD_ONLY and render_kw_only_separator:
|
|
# We have a keyword-only parameter to render and we haven't
|
|
# rendered an '*args'-like parameter before, so add a '*'
|
|
# separator to the parameters list ("foo(arg1, *, arg2)" case)
|
|
result.append('*')
|
|
# This condition should be only triggered once, so
|
|
# reset the flag
|
|
render_kw_only_separator = False
|
|
|
|
result.append(formatted)
|
|
|
|
if render_pos_only_separator:
|
|
# There were only positional-only parameters, hence the
|
|
# flag was not reset to 'False'
|
|
result.append('/')
|
|
|
|
rendered = '({})'.format(', '.join(result))
|
|
|
|
if self.return_annotation is not _empty:
|
|
anno = formatannotation(self.return_annotation)
|
|
rendered += ' -> {}'.format(anno)
|
|
|
|
return rendered
|
|
|
|
|
|
def signature(obj, *, follow_wrapped=True):
|
|
"""Get a signature object for the passed callable."""
|
|
return Signature.from_callable(obj, follow_wrapped=follow_wrapped)
|
|
|
|
|
|
def _main():
|
|
""" Logic for inspecting an object given at command line """
|
|
import argparse
|
|
import importlib
|
|
|
|
parser = argparse.ArgumentParser()
|
|
parser.add_argument(
|
|
'object',
|
|
help="The object to be analysed. "
|
|
"It supports the 'module:qualname' syntax")
|
|
parser.add_argument(
|
|
'-d', '--details', action='store_true',
|
|
help='Display info about the module rather than its source code')
|
|
|
|
args = parser.parse_args()
|
|
|
|
target = args.object
|
|
mod_name, has_attrs, attrs = target.partition(":")
|
|
try:
|
|
obj = module = importlib.import_module(mod_name)
|
|
except Exception as exc:
|
|
msg = "Failed to import {} ({}: {})".format(mod_name,
|
|
type(exc).__name__,
|
|
exc)
|
|
print(msg, file=sys.stderr)
|
|
exit(2)
|
|
|
|
if has_attrs:
|
|
parts = attrs.split(".")
|
|
obj = module
|
|
for part in parts:
|
|
obj = getattr(obj, part)
|
|
|
|
if module.__name__ in sys.builtin_module_names:
|
|
print("Can't get info for builtin modules.", file=sys.stderr)
|
|
exit(1)
|
|
|
|
if args.details:
|
|
print('Target: {}'.format(target))
|
|
print('Origin: {}'.format(getsourcefile(module)))
|
|
print('Cached: {}'.format(module.__cached__))
|
|
if obj is module:
|
|
print('Loader: {}'.format(repr(module.__loader__)))
|
|
if hasattr(module, '__path__'):
|
|
print('Submodule search path: {}'.format(module.__path__))
|
|
else:
|
|
try:
|
|
__, lineno = findsource(obj)
|
|
except Exception:
|
|
pass
|
|
else:
|
|
print('Line: {}'.format(lineno))
|
|
|
|
print('\n')
|
|
else:
|
|
print(getsource(obj))
|
|
|
|
|
|
if __name__ == "__main__":
|
|
_main()
|