3134 lines
114 KiB
Python
3134 lines
114 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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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 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 a __set__ or a __delete__ 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__") or hasattr(tp, "__delete__")
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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, types.BuiltinMethodType)):
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kind = "static method"
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obj = dict_obj
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elif isinstance(dict_obj, (classmethod, types.ClassMethodDescriptorType)):
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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
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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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if stop is None:
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def _is_wrapper(f):
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return hasattr(f, '__wrapped__')
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else:
|
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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
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# ensure they aren't destroyed, which would allow their IDs to be reused.
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memo = {id(f): f}
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recursion_limit = sys.getrecursionlimit()
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while _is_wrapper(func):
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func = func.__wrapped__
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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 getattr(object, '__file__', None):
|
|
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 getattr(object, '__file__', None):
|
|
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('module, class, method, function, traceback, frame, or '
|
|
'code object was expected, got {}'.format(
|
|
type(object).__name__))
|
|
|
|
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 parent not 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.
|
|
|
|
Deprecated since Python 3.5: use the `signature` function and `Signature`
|
|
objects.
|
|
"""
|
|
|
|
from warnings import warn
|
|
|
|
warn("`formatargspec` is deprecated since Python 3.5. Use `signature` and "
|
|
"the `Signature` object directly",
|
|
DeprecationWarning,
|
|
stacklevel=2)
|
|
|
|
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 (isinstance(class_dict, 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
|
|
isinstance(dict_attr, 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.
|
|
"""
|
|
# Lazy import ast because it's relatively heavy and
|
|
# it's not used for other than this function.
|
|
import ast
|
|
|
|
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 is not 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 (not sig_params or
|
|
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_
|
|
|
|
@property
|
|
def description(self):
|
|
return _PARAM_NAME_MAPPING[self]
|
|
|
|
_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
|
|
|
|
_PARAM_NAME_MAPPING = {
|
|
_POSITIONAL_ONLY: 'positional-only',
|
|
_POSITIONAL_OR_KEYWORD: 'positional or keyword',
|
|
_VAR_POSITIONAL: 'variadic positional',
|
|
_KEYWORD_ONLY: 'keyword-only',
|
|
_VAR_KEYWORD: 'variadic 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):
|
|
try:
|
|
self._kind = _ParameterKind(kind)
|
|
except ValueError:
|
|
raise ValueError(f'value {kind!r} is not a valid Parameter.kind')
|
|
if default is not _empty:
|
|
if self._kind in (_VAR_POSITIONAL, _VAR_KEYWORD):
|
|
msg = '{} parameters cannot have default values'
|
|
msg = msg.format(self._kind.description)
|
|
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):
|
|
msg = 'name must be a str, not a {}'.format(type(name).__name__)
|
|
raise TypeError(msg)
|
|
|
|
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 self._kind != _POSITIONAL_OR_KEYWORD:
|
|
msg = (
|
|
'implicit arguments must be passed as '
|
|
'positional or keyword arguments, not {}'
|
|
)
|
|
msg = msg.format(self._kind.description)
|
|
raise ValueError(msg)
|
|
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:
|
|
if self._annotation is not _empty:
|
|
formatted = '{} = {}'.format(formatted, repr(self._default))
|
|
else:
|
|
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: {} parameter before {} '
|
|
'parameter'
|
|
)
|
|
msg = msg.format(top_kind.description,
|
|
kind.description)
|
|
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()
|