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Diffstat (limited to 'sources/pyside2/PySide2/support/signature/inspect.py')
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diff --git a/sources/pyside2/PySide2/support/signature/inspect.py b/sources/pyside2/PySide2/support/signature/inspect.py new file mode 100644 index 000000000..23554d40a --- /dev/null +++ b/sources/pyside2/PySide2/support/signature/inspect.py @@ -0,0 +1,3115 @@ +# This Python file uses the following encoding: utf-8 +# It has been edited by fix-complaints.py . + +""" +PSF LICENSE AGREEMENT FOR PYTHON 3.6.2¶ +1. This LICENSE AGREEMENT is between the Python Software Foundation ("PSF"), and + the Individual or Organization ("Licensee") accessing and otherwise using Python + 3.6.2 software in source or binary form and its associated documentation. + +2. Subject to the terms and conditions of this License Agreement, PSF hereby + grants Licensee a nonexclusive, royalty-free, world-wide license to reproduce, + analyze, test, perform and/or display publicly, prepare derivative works, + distribute, and otherwise use Python 3.6.2 alone or in any derivative + version, provided, however, that PSF's License Agreement and PSF's notice of + copyright, i.e., "Copyright © 2001-2017 Python Software Foundation; All Rights + Reserved" are retained in Python 3.6.2 alone or in any derivative version + prepared by Licensee. + +3. In the event Licensee prepares a derivative work that is based on or + incorporates Python 3.6.2 or any part thereof, and wants to make the + derivative work available to others as provided herein, then Licensee hereby + agrees to include in any such work a brief summary of the changes made to Python + 3.6.2. + +4. PSF is making Python 3.6.2 available to Licensee on an "AS IS" basis. + PSF MAKES NO REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED. BY WAY OF + EXAMPLE, BUT NOT LIMITATION, PSF MAKES NO AND DISCLAIMS ANY REPRESENTATION OR + WARRANTY OF MERCHANTABILITY OR FITNESS FOR ANY PARTICULAR PURPOSE OR THAT THE + USE OF PYTHON 3.6.2 WILL NOT INFRINGE ANY THIRD PARTY RIGHTS. + +5. PSF SHALL NOT BE LIABLE TO LICENSEE OR ANY OTHER USERS OF PYTHON 3.6.2 + FOR ANY INCIDENTAL, SPECIAL, OR CONSEQUENTIAL DAMAGES OR LOSS AS A RESULT OF + MODIFYING, DISTRIBUTING, OR OTHERWISE USING PYTHON 3.6.2, OR ANY DERIVATIVE + THEREOF, EVEN IF ADVISED OF THE POSSIBILITY THEREOF. + +6. This License Agreement will automatically terminate upon a material breach of + its terms and conditions. + +7. Nothing in this License Agreement shall be deemed to create any relationship + of agency, partnership, or joint venture between PSF and Licensee. This License + Agreement does not grant permission to use PSF trademarks or trade name in a + trademark sense to endorse or promote products or services of Licensee, or any + third party. + +8. By copying, installing or otherwise using Python 3.6.2, Licensee agrees + to be bound by the terms and conditions of this License Agreement. +""" + +# This module is in the public domain. No warranties. + +__author__ = ('Ka-Ping Yee <ping@lfw.org>', + 'Yury Selivanov <yselivanov@sprymix.com>') + +import abc +import ast +import dis +import collections.abc +import enum +import importlib.machinery +import itertools +import linecache +import os +import re +import sys +import tokenize +import token +import types +import warnings +import functools +import builtins +from operator import attrgetter +from collections import namedtuple, OrderedDict + +# Create constants for the compiler flags in Include/code.h +# We try to get them from dis to avoid duplication +mod_dict = globals() +for k, v in dis.COMPILER_FLAG_NAMES.items(): + mod_dict["CO_" + v] = k + +# See Include/object.h +TPFLAGS_IS_ABSTRACT = 1 << 20 + +# ----------------------------------------------------------- type-checking +def ismodule(object): + """Return true if the object is a module. + + Module objects provide these attributes: + __cached__ pathname to byte compiled file + __doc__ documentation string + __file__ filename (missing for built-in modules)""" + return isinstance(object, types.ModuleType) + +def isclass(object): + """Return true if the object is a class. + + Class objects provide these attributes: + __doc__ documentation string + __module__ name of module in which this class was defined""" + return isinstance(object, type) + +def ismethod(object): + """Return true if the object is an instance method. + + Instance method objects provide these attributes: + __doc__ documentation string + __name__ name with which this method was defined + __func__ function object containing implementation of method + __self__ instance to which this method is bound""" + return isinstance(object, types.MethodType) + +def ismethoddescriptor(object): + """Return true if the object is a method descriptor. + + But not if ismethod() or isclass() or isfunction() are true. + + This is new in Python 2.2, and, for example, is true of int.__add__. + An object passing this test has a __get__ attribute but not a __set__ + attribute, but beyond that the set of attributes varies. __name__ is + usually sensible, and __doc__ often is. + + Methods implemented via descriptors that also pass one of the other + tests return false from the ismethoddescriptor() test, simply because + the other tests promise more -- you can, e.g., count on having the + __func__ attribute (etc) when an object passes ismethod().""" + if isclass(object) or ismethod(object) or isfunction(object): + # mutual exclusion + return False + tp = type(object) + return hasattr(tp, "__get__") and not hasattr(tp, "__set__") + +def isdatadescriptor(object): + """Return true if the object is a data descriptor. + + Data descriptors have both a __get__ and a __set__ attribute. Examples are + properties (defined in Python) and getsets and members (defined in C). + Typically, data descriptors will also have __name__ and __doc__ attributes + (properties, getsets, and members have both of these attributes), but this + is not guaranteed.""" + if isclass(object) or ismethod(object) or isfunction(object): + # mutual exclusion + return False + tp = type(object) + return hasattr(tp, "__set__") and hasattr(tp, "__get__") + +if hasattr(types, 'MemberDescriptorType'): + # CPython and equivalent + def ismemberdescriptor(object): + """Return true if the object is a member descriptor. + + Member descriptors are specialized descriptors defined in extension + modules.""" + return isinstance(object, types.MemberDescriptorType) +else: + # Other implementations + def ismemberdescriptor(object): + """Return true if the object is a member descriptor. + + Member descriptors are specialized descriptors defined in extension + modules.""" + return False + +if hasattr(types, 'GetSetDescriptorType'): + # CPython and equivalent + def isgetsetdescriptor(object): + """Return true if the object is a getset descriptor. + + getset descriptors are specialized descriptors defined in extension + modules.""" + return isinstance(object, types.GetSetDescriptorType) +else: + # Other implementations + def isgetsetdescriptor(object): + """Return true if the object is a getset descriptor. + + getset descriptors are specialized descriptors defined in extension + modules.""" + return False + +def isfunction(object): + """Return true if the object is a user-defined function. + + Function objects provide these attributes: + __doc__ documentation string + __name__ name with which this function was defined + __code__ code object containing compiled function bytecode + __defaults__ tuple of any default values for arguments + __globals__ global namespace in which this function was defined + __annotations__ dict of parameter annotations + __kwdefaults__ dict of keyword only parameters with defaults""" + return isinstance(object, types.FunctionType) + +def isgeneratorfunction(object): + """Return true if the object is a user-defined generator function. + + Generator function objects provide the same attributes as functions. + See help(isfunction) for a list of attributes.""" + return bool((isfunction(object) or ismethod(object)) and + object.__code__.co_flags & CO_GENERATOR) + +def iscoroutinefunction(object): + """Return true if the object is a coroutine function. + + Coroutine functions are defined with "async def" syntax. + """ + return bool((isfunction(object) or ismethod(object)) and + object.__code__.co_flags & CO_COROUTINE) + +def isasyncgenfunction(object): + """Return true if the object is an asynchronous generator function. + + Asynchronous generator functions are defined with "async def" + syntax and have "yield" expressions in their body. + """ + return bool((isfunction(object) or ismethod(object)) and + object.__code__.co_flags & CO_ASYNC_GENERATOR) + +def isasyncgen(object): + """Return true if the object is an asynchronous generator.""" + return isinstance(object, types.AsyncGeneratorType) + +def isgenerator(object): + """Return true if the object is a generator. + + Generator objects provide these attributes: + __iter__ defined to support iteration over container + close raises a new GeneratorExit exception inside the + generator to terminate the iteration + gi_code code object + gi_frame frame object or possibly None once the generator has + been exhausted + gi_running set to 1 when generator is executing, 0 otherwise + next return the next item from the container + send resumes the generator and "sends" a value that becomes + the result of the current yield-expression + throw used to raise an exception inside the generator""" + return isinstance(object, types.GeneratorType) + +def iscoroutine(object): + """Return true if the object is a coroutine.""" + return isinstance(object, types.CoroutineType) + +def isawaitable(object): + """Return true if object can be passed to an ``await`` expression.""" + return (isinstance(object, types.CoroutineType) or + isinstance(object, types.GeneratorType) and + bool(object.gi_code.co_flags & CO_ITERABLE_COROUTINE) or + isinstance(object, collections.abc.Awaitable)) + +def istraceback(object): + """Return true if the object is a traceback. + + Traceback objects provide these attributes: + tb_frame frame object at this level + tb_lasti index of last attempted instruction in bytecode + tb_lineno current line number in Python source code + tb_next next inner traceback object (called by this level)""" + return isinstance(object, types.TracebackType) + +def isframe(object): + """Return true if the object is a frame object. + + Frame objects provide these attributes: + f_back next outer frame object (this frame's caller) + f_builtins built-in namespace seen by this frame + f_code code object being executed in this frame + f_globals global namespace seen by this frame + f_lasti index of last attempted instruction in bytecode + f_lineno current line number in Python source code + f_locals local namespace seen by this frame + f_trace tracing function for this frame, or None""" + return isinstance(object, types.FrameType) + +def iscode(object): + """Return true if the object is a code object. + + Code objects provide these attributes: + co_argcount number of arguments (not including *, ** args + or keyword only arguments) + co_code string of raw compiled bytecode + co_cellvars tuple of names of cell variables + co_consts tuple of constants used in the bytecode + co_filename name of file in which this code object was created + co_firstlineno number of first line in Python source code + co_flags bitmap: 1=optimized | 2=newlocals | 4=*arg | 8=**arg + | 16=nested | 32=generator | 64=nofree | 128=coroutine + | 256=iterable_coroutine | 512=async_generator + co_freevars tuple of names of free variables + co_kwonlyargcount number of keyword only arguments (not including ** arg) + co_lnotab encoded mapping of line numbers to bytecode indices + co_name name with which this code object was defined + co_names tuple of names of local variables + co_nlocals number of local variables + co_stacksize virtual machine stack space required + co_varnames tuple of names of arguments and local variables""" + return isinstance(object, types.CodeType) + +def isbuiltin(object): + """Return true if the object is a built-in function or method. + + Built-in functions and methods provide these attributes: + __doc__ documentation string + __name__ original name of this function or method + __self__ instance to which a method is bound, or None""" + return isinstance(object, types.BuiltinFunctionType) + +def isroutine(object): + """Return true if the object is any kind of function or method.""" + return (isbuiltin(object) + or isfunction(object) + or ismethod(object) + or ismethoddescriptor(object)) + +def isabstract(object): + """Return true if the object is an abstract base class (ABC).""" + if not isinstance(object, type): + return False + if object.__flags__ & TPFLAGS_IS_ABSTRACT: + return True + if not issubclass(type(object), abc.ABCMeta): + return False + if hasattr(object, '__abstractmethods__'): + # It looks like ABCMeta.__new__ has finished running; + # TPFLAGS_IS_ABSTRACT should have been accurate. + return False + # It looks like ABCMeta.__new__ has not finished running yet; we're + # probably in __init_subclass__. We'll look for abstractmethods manually. + for name, value in object.__dict__.items(): + if getattr(value, "__isabstractmethod__", False): + return True + for base in object.__bases__: + for name in getattr(base, "__abstractmethods__", ()): + value = getattr(object, name, None) + if getattr(value, "__isabstractmethod__", False): + return True + return False + +def getmembers(object, predicate=None): + """Return all members of an object as (name, value) pairs sorted by name. + Optionally, only return members that satisfy a given predicate.""" + if isclass(object): + mro = (object,) + getmro(object) + else: + mro = () + results = [] + processed = set() + names = dir(object) + # :dd any DynamicClassAttributes to the list of names if object is a class; + # this may result in duplicate entries if, for example, a virtual + # attribute with the same name as a DynamicClassAttribute exists + try: + for base in object.__bases__: + for k, v in base.__dict__.items(): + if isinstance(v, types.DynamicClassAttribute): + names.append(k) + except AttributeError: + pass + for key in names: + # First try to get the value via getattr. Some descriptors don't + # like calling their __get__ (see bug #1785), so fall back to + # looking in the __dict__. + try: + value = getattr(object, key) + # handle the duplicate key + if key in processed: + raise AttributeError + except AttributeError: + for base in mro: + if key in base.__dict__: + value = base.__dict__[key] + break + else: + # could be a (currently) missing slot member, or a buggy + # __dir__; discard and move on + continue + if not predicate or predicate(value): + results.append((key, value)) + processed.add(key) + results.sort(key=lambda pair: pair[0]) + return results + +Attribute = namedtuple('Attribute', 'name kind defining_class object') + +def classify_class_attrs(cls): + """Return list of attribute-descriptor tuples. + + For each name in dir(cls), the return list contains a 4-tuple + with these elements: + + 0. The name (a string). + + 1. The kind of attribute this is, one of these strings: + 'class method' created via classmethod() + 'static method' created via staticmethod() + 'property' created via property() + 'method' any other flavor of method or descriptor + 'data' not a method + + 2. The class which defined this attribute (a class). + + 3. The object as obtained by calling getattr; if this fails, or if the + resulting object does not live anywhere in the class' mro (including + metaclasses) then the object is looked up in the defining class's + dict (found by walking the mro). + + If one of the items in dir(cls) is stored in the metaclass it will now + be discovered and not have None be listed as the class in which it was + defined. Any items whose home class cannot be discovered are skipped. + """ + + mro = getmro(cls) + metamro = getmro(type(cls)) # for attributes stored in the metaclass + metamro = tuple([cls for cls in metamro if cls not in (type, object)]) + class_bases = (cls,) + mro + all_bases = class_bases + metamro + names = dir(cls) + # :dd any DynamicClassAttributes to the list of names; + # this may result in duplicate entries if, for example, a virtual + # attribute with the same name as a DynamicClassAttribute exists. + for base in mro: + for k, v in base.__dict__.items(): + if isinstance(v, types.DynamicClassAttribute): + names.append(k) + result = [] + processed = set() + + for name in names: + # Get the object associated with the name, and where it was defined. + # Normal objects will be looked up with both getattr and directly in + # its class' dict (in case getattr fails [bug #1785], and also to look + # for a docstring). + # For DynamicClassAttributes on the second pass we only look in the + # class's dict. + # + # Getting an obj from the __dict__ sometimes reveals more than + # using getattr. Static and class methods are dramatic examples. + homecls = None + get_obj = None + dict_obj = None + if name not in processed: + try: + if name == '__dict__': + raise Exception("__dict__ is special, don't want the proxy") + get_obj = getattr(cls, name) + except Exception as exc: + pass + else: + homecls = getattr(get_obj, "__objclass__", homecls) + if homecls not in class_bases: + # if the resulting object does not live somewhere in the + # mro, drop it and search the mro manually + homecls = None + last_cls = None + # first look in the classes + for srch_cls in class_bases: + srch_obj = getattr(srch_cls, name, None) + if srch_obj is get_obj: + last_cls = srch_cls + # then check the metaclasses + for srch_cls in metamro: + try: + srch_obj = srch_cls.__getattr__(cls, name) + except AttributeError: + continue + if srch_obj is get_obj: + last_cls = srch_cls + if last_cls is not None: + homecls = last_cls + for base in all_bases: + if name in base.__dict__: + dict_obj = base.__dict__[name] + if homecls not in metamro: + homecls = base + break + if homecls is None: + # unable to locate the attribute anywhere, most likely due to + # buggy custom __dir__; discard and move on + continue + obj = get_obj if get_obj is not None else dict_obj + # Classify the object or its descriptor. + if isinstance(dict_obj, staticmethod): + kind = "static method" + obj = dict_obj + elif isinstance(dict_obj, classmethod): + kind = "class method" + obj = dict_obj + elif isinstance(dict_obj, property): + kind = "property" + obj = dict_obj + elif isroutine(obj): + kind = "method" + else: + kind = "data" + result.append(Attribute(name, kind, homecls, obj)) + processed.add(name) + return result + +# ----------------------------------------------------------- class helpers + +def getmro(cls): + "Return tuple of base classes (including cls) in method resolution order." + return cls.__mro__ + +# -------------------------------------------------------- function helpers + +def unwrap(func, *, stop=None): + """Get the object wrapped by *func*. + + Follows the chain of :attr:`__wrapped__` attributes returning the last + object in the chain. + + *stop* is an optional callback accepting an object in the wrapper chain + as its sole argument that allows the unwrapping to be terminated early if + the callback returns a true value. If the callback never returns a true + value, the last object in the chain is returned as usual. For example, + :func:`signature` uses this to stop unwrapping if any object in the + chain has a ``__signature__`` attribute defined. + + :exc:`ValueError` is raised if a cycle is encountered. + + """ + if stop is None: + def _is_wrapper(f): + return hasattr(f, '__wrapped__') + else: + def _is_wrapper(f): + return hasattr(f, '__wrapped__') and not stop(f) + f = func # remember the original func for error reporting + memo = {id(f)} # Memoise by id to tolerate non-hashable objects + while _is_wrapper(func): + func = func.__wrapped__ + id_func = id(func) + if id_func in memo: + raise ValueError('wrapper loop when unwrapping {!r}'.format(f)) + memo.add(id_func) + return func + +# -------------------------------------------------- source code extraction +def indentsize(line): + """Return the indent size, in spaces, at the start of a line of text.""" + expline = line.expandtabs() + return len(expline) - len(expline.lstrip()) + +def _findclass(func): + cls = sys.modules.get(func.__module__) + if cls is None: + return None + for name in func.__qualname__.split('.')[:-1]: + cls = getattr(cls, name) + if not isclass(cls): + return None + return cls + +def _finddoc(obj): + if isclass(obj): + for base in obj.__mro__: + if base is not object: + try: + doc = base.__doc__ + except AttributeError: + continue + if doc is not None: + return doc + return None + + if ismethod(obj): + name = obj.__func__.__name__ + self = obj.__self__ + if (isclass(self) and + getattr(getattr(self, name, None), '__func__') is obj.__func__): + # classmethod + cls = self + else: + cls = self.__class__ + elif isfunction(obj): + name = obj.__name__ + cls = _findclass(obj) + if cls is None or getattr(cls, name) is not obj: + return None + elif isbuiltin(obj): + name = obj.__name__ + self = obj.__self__ + if (isclass(self) and + self.__qualname__ + '.' + name == obj.__qualname__): + # classmethod + cls = self + else: + cls = self.__class__ + # Should be tested before isdatadescriptor(). + elif isinstance(obj, property): + func = obj.fget + name = func.__name__ + cls = _findclass(func) + if cls is None or getattr(cls, name) is not obj: + return None + elif ismethoddescriptor(obj) or isdatadescriptor(obj): + name = obj.__name__ + cls = obj.__objclass__ + if getattr(cls, name) is not obj: + return None + else: + return None + + for base in cls.__mro__: + try: + doc = getattr(base, name).__doc__ + except AttributeError: + continue + if doc is not None: + return doc + return None + +def getdoc(object): + """Get the documentation string for an object. + + All tabs are expanded to spaces. To clean up docstrings that are + indented to line up with blocks of code, any whitespace than can be + uniformly removed from the second line onwards is removed.""" + try: + doc = object.__doc__ + except AttributeError: + return None + if doc is None: + try: + doc = _finddoc(object) + except (AttributeError, TypeError): + return None + if not isinstance(doc, str): + return None + return cleandoc(doc) + +def cleandoc(doc): + """Clean up indentation from docstrings. + + Any whitespace that can be uniformly removed from the second line + onwards is removed.""" + try: + lines = doc.expandtabs().split('\n') + except UnicodeError: + return None + else: + # Find minimum indentation of any non-blank lines after first line. + margin = sys.maxsize + for line in lines[1:]: + content = len(line.lstrip()) + if content: + indent = len(line) - content + margin = min(margin, indent) + # Remove indentation. + if lines: + lines[0] = lines[0].lstrip() + if margin < sys.maxsize: + for i in range(1, len(lines)): lines[i] = lines[i][margin:] + # Remove any trailing or leading blank lines. + while lines and not lines[-1]: + lines.pop() + while lines and not lines[0]: + lines.pop(0) + return '\n'.join(lines) + +def getfile(object): + """Work out which source or compiled file an object was defined in.""" + if ismodule(object): + if hasattr(object, '__file__'): + return object.__file__ + raise TypeError('{!r} is a built-in module'.format(object)) + if isclass(object): + if hasattr(object, '__module__'): + object = sys.modules.get(object.__module__) + if hasattr(object, '__file__'): + return object.__file__ + raise TypeError('{!r} is a built-in class'.format(object)) + if ismethod(object): + object = object.__func__ + if isfunction(object): + object = object.__code__ + if istraceback(object): + object = object.tb_frame + if isframe(object): + object = object.f_code + if iscode(object): + return object.co_filename + raise TypeError('{!r} is not a module, class, method, ' + 'function, traceback, frame, or code object'.format(object)) + +def getmodulename(path): + """Return the module name for a given file, or None.""" + fname = os.path.basename(path) + # Check for paths that look like an actual module file + suffixes = [(-len(suffix), suffix) + for suffix in importlib.machinery.all_suffixes()] + suffixes.sort() # try longest suffixes first, in case they overlap + for neglen, suffix in suffixes: + if fname.endswith(suffix): + return fname[:neglen] + return None + +def getsourcefile(object): + """Return the filename that can be used to locate an object's source. + Return None if no way can be identified to get the source. + """ + filename = getfile(object) + all_bytecode_suffixes = importlib.machinery.DEBUG_BYTECODE_SUFFIXES[:] + all_bytecode_suffixes += importlib.machinery.OPTIMIZED_BYTECODE_SUFFIXES[:] + if any(filename.endswith(s) for s in all_bytecode_suffixes): + filename = (os.path.splitext(filename)[0] + + importlib.machinery.SOURCE_SUFFIXES[0]) + elif any(filename.endswith(s) for s in + importlib.machinery.EXTENSION_SUFFIXES): + return None + if os.path.exists(filename): + return filename + # only return a non-existent filename if the module has a PEP 302 loader + if getattr(getmodule(object, filename), '__loader__', None) is not None: + return filename + # or it is in the linecache + if filename in linecache.cache: + return filename + +def getabsfile(object, _filename=None): + """Return an absolute path to the source or compiled file for an object. + + The idea is for each object to have a unique origin, so this routine + normalizes the result as much as possible.""" + if _filename is None: + _filename = getsourcefile(object) or getfile(object) + return os.path.normcase(os.path.abspath(_filename)) + +modulesbyfile = {} +_filesbymodname = {} + +def getmodule(object, _filename=None): + """Return the module an object was defined in, or None if not found.""" + if ismodule(object): + return object + if hasattr(object, '__module__'): + return sys.modules.get(object.__module__) + # Try the filename to modulename cache + if _filename is not None and _filename in modulesbyfile: + return sys.modules.get(modulesbyfile[_filename]) + # Try the cache again with the absolute file name + try: + file = getabsfile(object, _filename) + except TypeError: + return None + if file in modulesbyfile: + return sys.modules.get(modulesbyfile[file]) + # Update the filename to module name cache and check yet again + # Copy sys.modules in order to cope with changes while iterating + for modname, module in list(sys.modules.items()): + if ismodule(module) and hasattr(module, '__file__'): + f = module.__file__ + if f == _filesbymodname.get(modname, None): + # Have already mapped this module, so skip it + continue + _filesbymodname[modname] = f + f = getabsfile(module) + # Always map to the name the module knows itself by + modulesbyfile[f] = modulesbyfile[ + os.path.realpath(f)] = module.__name__ + if file in modulesbyfile: + return sys.modules.get(modulesbyfile[file]) + # Check the main module + main = sys.modules['__main__'] + if not hasattr(object, '__name__'): + return None + if hasattr(main, object.__name__): + mainobject = getattr(main, object.__name__) + if mainobject is object: + return main + # Check builtins + builtin = sys.modules['builtins'] + if hasattr(builtin, object.__name__): + builtinobject = getattr(builtin, object.__name__) + if builtinobject is object: + return builtin + +def findsource(object): + """Return the entire source file and starting line number for an object. + + The argument may be a module, class, method, function, traceback, frame, + or code object. The source code is returned as a list of all the lines + in the file and the line number indexes a line in that list. An OSError + is raised if the source code cannot be retrieved.""" + + file = getsourcefile(object) + if file: + # Invalidate cache if needed. + linecache.checkcache(file) + else: + file = getfile(object) + # Allow filenames in form of "<something>" to pass through. + # `doctest` monkeypatches `linecache` module to enable + # inspection, so let `linecache.getlines` to be called. + if not (file.startswith('<') and file.endswith('>')): + raise OSError('source code not available') + + module = getmodule(object, file) + if module: + lines = linecache.getlines(file, module.__dict__) + else: + lines = linecache.getlines(file) + if not lines: + raise OSError('could not get source code') + + if ismodule(object): + return lines, 0 + + if isclass(object): + name = object.__name__ + pat = re.compile(r'^(\s*)class\s*' + name + r'\b') + # make some effort to find the best matching class definition: + # use the one with the least indentation, which is the one + # that's most probably not inside a function definition. + candidates = [] + for i in range(len(lines)): + match = pat.match(lines[i]) + if match: + # if it's at toplevel, it's already the best one + if lines[i][0] == 'c': + return lines, i + # else add whitespace to candidate list + candidates.append((match.group(1), i)) + if candidates: + # this will sort by whitespace, and by line number, + # less whitespace first + candidates.sort() + return lines, candidates[0][1] + else: + raise OSError('could not find class definition') + + if ismethod(object): + object = object.__func__ + if isfunction(object): + object = object.__code__ + if istraceback(object): + object = object.tb_frame + if isframe(object): + object = object.f_code + if iscode(object): + if not hasattr(object, 'co_firstlineno'): + raise OSError('could not find function definition') + lnum = object.co_firstlineno - 1 + pat = re.compile(r'^(\s*def\s)|(\s*async\s+def\s)|(.*(?<!\w)lambda(:|\s))|^(\s*@)') + while lnum > 0: + if pat.match(lines[lnum]): break + lnum = lnum - 1 + return lines, lnum + raise OSError('could not find code object') + +def getcomments(object): + """Get lines of comments immediately preceding an object's source code. + + Returns None when source can't be found. + """ + try: + lines, lnum = findsource(object) + except (OSError, TypeError): + return None + + if ismodule(object): + # Look for a comment block at the top of the file. + start = 0 + if lines and lines[0][:2] == '#!': start = 1 + while start < len(lines) and lines[start].strip() in ('', '#'): + start = start + 1 + if start < len(lines) and lines[start][:1] == '#': + comments = [] + end = start + while end < len(lines) and lines[end][:1] == '#': + comments.append(lines[end].expandtabs()) + end = end + 1 + return ''.join(comments) + + # Look for a preceding block of comments at the same indentation. + elif lnum > 0: + indent = indentsize(lines[lnum]) + end = lnum - 1 + if end >= 0 and lines[end].lstrip()[:1] == '#' and \ + indentsize(lines[end]) == indent: + comments = [lines[end].expandtabs().lstrip()] + if end > 0: + end = end - 1 + comment = lines[end].expandtabs().lstrip() + while comment[:1] == '#' and indentsize(lines[end]) == indent: + comments[:0] = [comment] + end = end - 1 + if end < 0: break + comment = lines[end].expandtabs().lstrip() + while comments and comments[0].strip() == '#': + comments[:1] = [] + while comments and comments[-1].strip() == '#': + comments[-1:] = [] + return ''.join(comments) + +class EndOfBlock(Exception): pass + +class BlockFinder: + """Provide a tokeneater() method to detect the end of a code block.""" + def __init__(self): + self.indent = 0 + self.islambda = False + self.started = False + self.passline = False + self.indecorator = False + self.decoratorhasargs = False + self.last = 1 + + def tokeneater(self, type, token, srowcol, erowcol, line): + if not self.started and not self.indecorator: + # skip any decorators + if token == "@": + self.indecorator = True + # look for the first "def", "class" or "lambda" + elif token in ("def", "class", "lambda"): + if token == "lambda": + self.islambda = True + self.started = True + self.passline = True # skip to the end of the line + elif token == "(": + if self.indecorator: + self.decoratorhasargs = True + elif token == ")": + if self.indecorator: + self.indecorator = False + self.decoratorhasargs = False + elif type == tokenize.NEWLINE: + self.passline = False # stop skipping when a NEWLINE is seen + self.last = srowcol[0] + if self.islambda: # lambdas always end at the first NEWLINE + raise EndOfBlock + # hitting a NEWLINE when in a decorator without args + # ends the decorator + if self.indecorator and not self.decoratorhasargs: + self.indecorator = False + elif self.passline: + pass + elif type == tokenize.INDENT: + self.indent = self.indent + 1 + self.passline = True + elif type == tokenize.DEDENT: + self.indent = self.indent - 1 + # the end of matching indent/dedent pairs end a block + # (note that this only works for "def"/"class" blocks, + # not e.g. for "if: else:" or "try: finally:" blocks) + if self.indent <= 0: + raise EndOfBlock + elif self.indent == 0 and type not in (tokenize.COMMENT, tokenize.NL): + # any other token on the same indentation level end the previous + # block as well, except the pseudo-tokens COMMENT and NL. + raise EndOfBlock + +def getblock(lines): + """Extract the block of code at the top of the given list of lines.""" + blockfinder = BlockFinder() + try: + tokens = tokenize.generate_tokens(iter(lines).__next__) + for _token in tokens: + blockfinder.tokeneater(*_token) + except (EndOfBlock, IndentationError): + pass + return lines[:blockfinder.last] + +def getsourcelines(object): + """Return a list of source lines and starting line number for an object. + + The argument may be a module, class, method, function, traceback, frame, + or code object. The source code is returned as a list of the lines + corresponding to the object and the line number indicates where in the + original source file the first line of code was found. An OSError is + raised if the source code cannot be retrieved.""" + object = unwrap(object) + lines, lnum = findsource(object) + + if ismodule(object): + return lines, 0 + else: + return getblock(lines[lnum:]), lnum + 1 + +def getsource(object): + """Return the text of the source code for an object. + + The argument may be a module, class, method, function, traceback, frame, + or code object. The source code is returned as a single string. An + OSError is raised if the source code cannot be retrieved.""" + lines, lnum = getsourcelines(object) + return ''.join(lines) + +# --------------------------------------------------- class tree extraction +def walktree(classes, children, parent): + """Recursive helper function for getclasstree().""" + results = [] + classes.sort(key=attrgetter('__module__', '__name__')) + for c in classes: + results.append((c, c.__bases__)) + if c in children: + results.append(walktree(children[c], children, c)) + return results + +def getclasstree(classes, unique=False): + """Arrange the given list of classes into a hierarchy of nested lists. + + Where a nested list appears, it contains classes derived from the class + whose entry immediately precedes the list. Each entry is a 2-tuple + containing a class and a tuple of its base classes. If the 'unique' + argument is true, exactly one entry appears in the returned structure + for each class in the given list. Otherwise, classes using multiple + inheritance and their descendants will appear multiple times.""" + children = {} + roots = [] + for c in classes: + if c.__bases__: + for parent in c.__bases__: + if not parent in children: + children[parent] = [] + if c not in children[parent]: + children[parent].append(c) + if unique and parent in classes: break + elif c not in roots: + roots.append(c) + for parent in children: + if parent not in classes: + roots.append(parent) + return walktree(roots, children, None) + +# ------------------------------------------------ argument list extraction +Arguments = namedtuple('Arguments', 'args, varargs, varkw') + +def getargs(co): + """Get information about the arguments accepted by a code object. + + Three things are returned: (args, varargs, varkw), where + 'args' is the list of argument names. Keyword-only arguments are + appended. 'varargs' and 'varkw' are the names of the * and ** + arguments or None.""" + args, varargs, kwonlyargs, varkw = _getfullargs(co) + return Arguments(args + kwonlyargs, varargs, varkw) + +def _getfullargs(co): + """Get information about the arguments accepted by a code object. + + Four things are returned: (args, varargs, kwonlyargs, varkw), where + 'args' and 'kwonlyargs' are lists of argument names, and 'varargs' + and 'varkw' are the names of the * and ** arguments or None.""" + + if not iscode(co): + raise TypeError('{!r} is not a code object'.format(co)) + + nargs = co.co_argcount + names = co.co_varnames + nkwargs = co.co_kwonlyargcount + args = list(names[:nargs]) + kwonlyargs = list(names[nargs:nargs+nkwargs]) + step = 0 + + nargs += nkwargs + varargs = None + if co.co_flags & CO_VARARGS: + varargs = co.co_varnames[nargs] + nargs = nargs + 1 + varkw = None + if co.co_flags & CO_VARKEYWORDS: + varkw = co.co_varnames[nargs] + return args, varargs, kwonlyargs, varkw + + +ArgSpec = namedtuple('ArgSpec', 'args varargs keywords defaults') + +def getargspec(func): + """Get the names and default values of a function's parameters. + + A tuple of four things is returned: (args, varargs, keywords, defaults). + 'args' is a list of the argument names, including keyword-only argument names. + 'varargs' and 'keywords' are the names of the * and ** parameters or None. + 'defaults' is an n-tuple of the default values of the last n parameters. + + This function is deprecated, as it does not support annotations or + keyword-only parameters and will raise ValueError if either is present + on the supplied callable. + + For a more structured introspection API, use inspect.signature() instead. + + Alternatively, use getfullargspec() for an API with a similar namedtuple + based interface, but full support for annotations and keyword-only + parameters. + """ + warnings.warn("inspect.getargspec() is deprecated, " + "use inspect.signature() or inspect.getfullargspec()", + DeprecationWarning, stacklevel=2) + args, varargs, varkw, defaults, kwonlyargs, kwonlydefaults, ann = \ + getfullargspec(func) + if kwonlyargs or ann: + raise ValueError("Function has keyword-only parameters or annotations" + ", use getfullargspec() API which can support them") + return ArgSpec(args, varargs, varkw, defaults) + +FullArgSpec = namedtuple('FullArgSpec', + 'args, varargs, varkw, defaults, kwonlyargs, kwonlydefaults, annotations') + +def getfullargspec(func): + """Get the names and default values of a callable object's parameters. + + A tuple of seven things is returned: + (args, varargs, varkw, defaults, kwonlyargs, kwonlydefaults, annotations). + 'args' is a list of the parameter names. + 'varargs' and 'varkw' are the names of the * and ** parameters or None. + 'defaults' is an n-tuple of the default values of the last n parameters. + 'kwonlyargs' is a list of keyword-only parameter names. + 'kwonlydefaults' is a dictionary mapping names from kwonlyargs to defaults. + 'annotations' is a dictionary mapping parameter names to annotations. + + Notable differences from inspect.signature(): + - the "self" parameter is always reported, even for bound methods + - wrapper chains defined by __wrapped__ *not* unwrapped automatically + """ + + try: + # Re: `skip_bound_arg=False` + # + # There is a notable difference in behavior 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 behavior, we "unbind" bound methods, to trick + # inspect.signature to always return their first parameter ("self", + # usually) + + # Re: `follow_wrapper_chains=False` + # + # getfullargspec() historically ignored __wrapped__ attributes, + # so we ensure that remains the case in 3.3+ + + sig = _signature_from_callable(func, + follow_wrapper_chains=False, + skip_bound_arg=False, + sigcls=Signature) + except Exception as ex: + # Most of the times 'signature' will raise ValueError. + # But, it can also raise AttributeError, and, maybe something + # else. So to be fully backwards compatible, we catch all + # possible exceptions here, and reraise a TypeError. + raise TypeError('unsupported callable') from ex + + args = [] + varargs = None + varkw = None + kwonlyargs = [] + defaults = () + annotations = {} + defaults = () + kwdefaults = {} + + if sig.return_annotation is not sig.empty: + annotations['return'] = sig.return_annotation + + for param in sig.parameters.values(): + kind = param.kind + name = param.name + + if kind is _POSITIONAL_ONLY: + args.append(name) + elif kind is _POSITIONAL_OR_KEYWORD: + args.append(name) + if param.default is not param.empty: + defaults += (param.default,) + elif kind is _VAR_POSITIONAL: + varargs = name + elif kind is _KEYWORD_ONLY: + kwonlyargs.append(name) + if param.default is not param.empty: + kwdefaults[name] = param.default + elif kind is _VAR_KEYWORD: + varkw = name + + if param.annotation is not param.empty: + annotations[name] = param.annotation + + if not kwdefaults: + # compatibility with 'func.__kwdefaults__' + kwdefaults = None + + if not defaults: + # compatibility with 'func.__defaults__' + defaults = None + + return FullArgSpec(args, varargs, varkw, defaults, + kwonlyargs, kwdefaults, annotations) + + +ArgInfo = namedtuple('ArgInfo', 'args varargs keywords locals') + +def getargvalues(frame): + """Get information about arguments passed into a particular frame. + + A tuple of four things is returned: (args, varargs, varkw, locals). + 'args' is a list of the argument names. + 'varargs' and 'varkw' are the names of the * and ** arguments or None. + 'locals' is the locals dictionary of the given frame.""" + args, varargs, varkw = getargs(frame.f_code) + return ArgInfo(args, varargs, varkw, frame.f_locals) + +def formatannotation(annotation, base_module=None): + if getattr(annotation, '__module__', None) == 'typing': + return repr(annotation).replace('typing.', '') + if isinstance(annotation, type): + if annotation.__module__ in ('builtins', base_module): + return annotation.__qualname__ + return annotation.__module__+'.'+annotation.__qualname__ + return repr(annotation) + +def formatannotationrelativeto(object): + module = getattr(object, '__module__', None) + def _formatannotation(annotation): + return formatannotation(annotation, module) + return _formatannotation + +def formatargspec(args, varargs=None, varkw=None, defaults=None, + kwonlyargs=(), kwonlydefaults={}, annotations={}, + formatarg=str, + formatvarargs=lambda name: '*' + name, + formatvarkw=lambda name: '**' + name, + formatvalue=lambda value: '=' + repr(value), + formatreturns=lambda text: ' -> ' + text, + formatannotation=formatannotation): + """Format an argument spec from the values returned by getfullargspec. + + The first seven arguments are (args, varargs, varkw, defaults, + kwonlyargs, kwonlydefaults, annotations). The other five arguments + are the corresponding optional formatting functions that are called to + turn names and values into strings. The last argument is an optional + function to format the sequence of arguments.""" + def formatargandannotation(arg): + result = formatarg(arg) + if arg in annotations: + result += ': ' + formatannotation(annotations[arg]) + return result + specs = [] + if defaults: + firstdefault = len(args) - len(defaults) + for i, arg in enumerate(args): + spec = formatargandannotation(arg) + if defaults and i >= firstdefault: + spec = spec + formatvalue(defaults[i - firstdefault]) + specs.append(spec) + if varargs is not None: + specs.append(formatvarargs(formatargandannotation(varargs))) + else: + if kwonlyargs: + specs.append('*') + if kwonlyargs: + for kwonlyarg in kwonlyargs: + spec = formatargandannotation(kwonlyarg) + if kwonlydefaults and kwonlyarg in kwonlydefaults: + spec += formatvalue(kwonlydefaults[kwonlyarg]) + specs.append(spec) + if varkw is not None: + specs.append(formatvarkw(formatargandannotation(varkw))) + result = '(' + ', '.join(specs) + ')' + if 'return' in annotations: + result += formatreturns(formatannotation(annotations['return'])) + return result + +def formatargvalues(args, varargs, varkw, locals, + formatarg=str, + formatvarargs=lambda name: '*' + name, + formatvarkw=lambda name: '**' + name, + formatvalue=lambda value: '=' + repr(value)): + """Format an argument spec from the 4 values returned by getargvalues. + + The first four arguments are (args, varargs, varkw, locals). The + next four arguments are the corresponding optional formatting functions + that are called to turn names and values into strings. The ninth + argument is an optional function to format the sequence of arguments.""" + def convert(name, locals=locals, + formatarg=formatarg, formatvalue=formatvalue): + return formatarg(name) + formatvalue(locals[name]) + specs = [] + for i in range(len(args)): + specs.append(convert(args[i])) + if varargs: + specs.append(formatvarargs(varargs) + formatvalue(locals[varargs])) + if varkw: + specs.append(formatvarkw(varkw) + formatvalue(locals[varkw])) + return '(' + ', '.join(specs) + ')' + +def _missing_arguments(f_name, argnames, pos, values): + names = [repr(name) for name in argnames if name not in values] + missing = len(names) + if missing == 1: + s = names[0] + elif missing == 2: + s = "{} and {}".format(*names) + else: + tail = ", {} and {}".format(*names[-2:]) + del names[-2:] + s = ", ".join(names) + tail + raise TypeError("%s() missing %i required %s argument%s: %s" % + (f_name, missing, + "positional" if pos else "keyword-only", + "" if missing == 1 else "s", s)) + +def _too_many(f_name, args, kwonly, varargs, defcount, given, values): + at_least = len(args) - defcount + kwonly_given = len([arg for arg in kwonly if arg in values]) + if varargs: + plural = at_least != 1 + sig = "at least %d" % (at_least,) + elif defcount: + plural = True + sig = "from %d to %d" % (at_least, len(args)) + else: + plural = len(args) != 1 + sig = str(len(args)) + kwonly_sig = "" + if kwonly_given: + msg = " positional argument%s (and %d keyword-only argument%s)" + kwonly_sig = (msg % ("s" if given != 1 else "", kwonly_given, + "s" if kwonly_given != 1 else "")) + raise TypeError("%s() takes %s positional argument%s but %d%s %s given" % + (f_name, sig, "s" if plural else "", given, kwonly_sig, + "was" if given == 1 and not kwonly_given else "were")) + +def getcallargs(*func_and_positional, **named): + """Get the mapping of arguments to values. + + A dict is returned, with keys the function argument names (including the + names of the * and ** arguments, if any), and values the respective bound + values from 'positional' and 'named'.""" + func = func_and_positional[0] + positional = func_and_positional[1:] + spec = getfullargspec(func) + args, varargs, varkw, defaults, kwonlyargs, kwonlydefaults, ann = spec + f_name = func.__name__ + arg2value = {} + + + if ismethod(func) and func.__self__ is not None: + # implicit 'self' (or 'cls' for classmethods) argument + positional = (func.__self__,) + positional + num_pos = len(positional) + num_args = len(args) + num_defaults = len(defaults) if defaults else 0 + + n = min(num_pos, num_args) + for i in range(n): + arg2value[args[i]] = positional[i] + if varargs: + arg2value[varargs] = tuple(positional[n:]) + possible_kwargs = set(args + kwonlyargs) + if varkw: + arg2value[varkw] = {} + for kw, value in named.items(): + if kw not in possible_kwargs: + if not varkw: + raise TypeError("%s() got an unexpected keyword argument %r" % + (f_name, kw)) + arg2value[varkw][kw] = value + continue + if kw in arg2value: + raise TypeError("%s() got multiple values for argument %r" % + (f_name, kw)) + arg2value[kw] = value + if num_pos > num_args and not varargs: + _too_many(f_name, args, kwonlyargs, varargs, num_defaults, + num_pos, arg2value) + if num_pos < num_args: + req = args[:num_args - num_defaults] + for arg in req: + if arg not in arg2value: + _missing_arguments(f_name, req, True, arg2value) + for i, arg in enumerate(args[num_args - num_defaults:]): + if arg not in arg2value: + arg2value[arg] = defaults[i] + missing = 0 + for kwarg in kwonlyargs: + if kwarg not in arg2value: + if kwonlydefaults and kwarg in kwonlydefaults: + arg2value[kwarg] = kwonlydefaults[kwarg] + else: + missing += 1 + if missing: + _missing_arguments(f_name, kwonlyargs, False, arg2value) + return arg2value + +ClosureVars = namedtuple('ClosureVars', 'nonlocals globals builtins unbound') + +def getclosurevars(func): + """ + Get the mapping of free variables to their current values. + + Returns a named tuple of dicts mapping the current nonlocal, global + and builtin references as seen by the body of the function. A final + set of unbound names that could not be resolved is also provided. + """ + + if ismethod(func): + func = func.__func__ + + if not isfunction(func): + raise TypeError("'{!r}' is not a Python function".format(func)) + + code = func.__code__ + # Nonlocal references are named in co_freevars and resolved + # by looking them up in __closure__ by positional index + if func.__closure__ is None: + nonlocal_vars = {} + else: + nonlocal_vars = { + var : cell.cell_contents + for var, cell in zip(code.co_freevars, func.__closure__) + } + + # Global and builtin references are named in co_names and resolved + # by looking them up in __globals__ or __builtins__ + global_ns = func.__globals__ + builtin_ns = global_ns.get("__builtins__", builtins.__dict__) + if ismodule(builtin_ns): + builtin_ns = builtin_ns.__dict__ + global_vars = {} + builtin_vars = {} + unbound_names = set() + for name in code.co_names: + if name in ("None", "True", "False"): + # Because these used to be builtins instead of keywords, they + # may still show up as name references. We ignore them. + continue + try: + global_vars[name] = global_ns[name] + except KeyError: + try: + builtin_vars[name] = builtin_ns[name] + except KeyError: + unbound_names.add(name) + + return ClosureVars(nonlocal_vars, global_vars, + builtin_vars, unbound_names) + +# -------------------------------------------------- stack frame extraction + +Traceback = namedtuple('Traceback', 'filename lineno function code_context index') + +def getframeinfo(frame, context=1): + """Get information about a frame or traceback object. + + A tuple of five things is returned: the filename, the line number of + the current line, the function name, a list of lines of context from + the source code, and the index of the current line within that list. + The optional second argument specifies the number of lines of context + to return, which are centered around the current line.""" + if istraceback(frame): + lineno = frame.tb_lineno + frame = frame.tb_frame + else: + lineno = frame.f_lineno + if not isframe(frame): + raise TypeError('{!r} is not a frame or traceback object'.format(frame)) + + filename = getsourcefile(frame) or getfile(frame) + if context > 0: + start = lineno - 1 - context//2 + try: + lines, lnum = findsource(frame) + except OSError: + lines = index = None + else: + start = max(0, min(start, len(lines) - context)) + lines = lines[start:start+context] + index = lineno - 1 - start + else: + lines = index = None + + return Traceback(filename, lineno, frame.f_code.co_name, lines, index) + +def getlineno(frame): + """Get the line number from a frame object, allowing for optimization.""" + # FrameType.f_lineno is now a descriptor that grovels co_lnotab + return frame.f_lineno + +FrameInfo = namedtuple('FrameInfo', ('frame',) + Traceback._fields) + +def getouterframes(frame, context=1): + """Get a list of records for a frame and all higher (calling) frames. + + Each record contains a frame object, filename, line number, function + name, a list of lines of context, and index within the context.""" + framelist = [] + while frame: + frameinfo = (frame,) + getframeinfo(frame, context) + framelist.append(FrameInfo(*frameinfo)) + frame = frame.f_back + return framelist + +def getinnerframes(tb, context=1): + """Get a list of records for a traceback's frame and all lower frames. + + Each record contains a frame object, filename, line number, function + name, a list of lines of context, and index within the context.""" + framelist = [] + while tb: + frameinfo = (tb.tb_frame,) + getframeinfo(tb, context) + framelist.append(FrameInfo(*frameinfo)) + tb = tb.tb_next + return framelist + +def currentframe(): + """Return the frame of the caller or None if this is not possible.""" + return sys._getframe(1) if hasattr(sys, "_getframe") else None + +def stack(context=1): + """Return a list of records for the stack above the caller's frame.""" + return getouterframes(sys._getframe(1), context) + +def trace(context=1): + """Return a list of records for the stack below the current exception.""" + return getinnerframes(sys.exc_info()[2], context) + + +# ------------------------------------------------ static version of getattr + +_sentinel = object() + +def _static_getmro(klass): + return type.__dict__['__mro__'].__get__(klass) + +def _check_instance(obj, attr): + instance_dict = {} + try: + instance_dict = object.__getattribute__(obj, "__dict__") + except AttributeError: + pass + return dict.get(instance_dict, attr, _sentinel) + + +def _check_class(klass, attr): + for entry in _static_getmro(klass): + if _shadowed_dict(type(entry)) is _sentinel: + try: + return entry.__dict__[attr] + except KeyError: + pass + return _sentinel + +def _is_type(obj): + try: + _static_getmro(obj) + except TypeError: + return False + return True + +def _shadowed_dict(klass): + dict_attr = type.__dict__["__dict__"] + for entry in _static_getmro(klass): + try: + class_dict = dict_attr.__get__(entry)["__dict__"] + except KeyError: + pass + else: + if not (type(class_dict) is types.GetSetDescriptorType and + class_dict.__name__ == "__dict__" and + class_dict.__objclass__ is entry): + return class_dict + return _sentinel + +def getattr_static(obj, attr, default=_sentinel): + """Retrieve attributes without triggering dynamic lookup via the + descriptor protocol, __getattr__ or __getattribute__. + + Note: this function may not be able to retrieve all attributes + that getattr can fetch (like dynamically created attributes) + and may find attributes that getattr can't (like descriptors + that raise AttributeError). It can also return descriptor objects + instead of instance members in some cases. See the + documentation for details. + """ + instance_result = _sentinel + if not _is_type(obj): + klass = type(obj) + dict_attr = _shadowed_dict(klass) + if (dict_attr is _sentinel or + type(dict_attr) is types.MemberDescriptorType): + instance_result = _check_instance(obj, attr) + else: + klass = obj + + klass_result = _check_class(klass, attr) + + if instance_result is not _sentinel and klass_result is not _sentinel: + if (_check_class(type(klass_result), '__get__') is not _sentinel and + _check_class(type(klass_result), '__set__') is not _sentinel): + return klass_result + + if instance_result is not _sentinel: + return instance_result + if klass_result is not _sentinel: + return klass_result + + if obj is klass: + # for types we check the metaclass too + for entry in _static_getmro(type(klass)): + if _shadowed_dict(type(entry)) is _sentinel: + try: + return entry.__dict__[attr] + except KeyError: + pass + if default is not _sentinel: + return default + raise AttributeError(attr) + + +# ------------------------------------------------ generator introspection + +GEN_CREATED = 'GEN_CREATED' +GEN_RUNNING = 'GEN_RUNNING' +GEN_SUSPENDED = 'GEN_SUSPENDED' +GEN_CLOSED = 'GEN_CLOSED' + +def getgeneratorstate(generator): + """Get current state of a generator-iterator. + + Possible states are: + GEN_CREATED: Waiting to start execution. + GEN_RUNNING: Currently being executed by the interpreter. + GEN_SUSPENDED: Currently suspended at a yield expression. + GEN_CLOSED: Execution has completed. + """ + if generator.gi_running: + return GEN_RUNNING + if generator.gi_frame is None: + return GEN_CLOSED + if generator.gi_frame.f_lasti == -1: + return GEN_CREATED + return GEN_SUSPENDED + + +def getgeneratorlocals(generator): + """ + Get the mapping of generator local variables to their current values. + + A dict is returned, with the keys the local variable names and values the + bound values.""" + + if not isgenerator(generator): + raise TypeError("'{!r}' is not a Python generator".format(generator)) + + frame = getattr(generator, "gi_frame", None) + if frame is not None: + return generator.gi_frame.f_locals + else: + return {} + + +# ------------------------------------------------ coroutine introspection + +CORO_CREATED = 'CORO_CREATED' +CORO_RUNNING = 'CORO_RUNNING' +CORO_SUSPENDED = 'CORO_SUSPENDED' +CORO_CLOSED = 'CORO_CLOSED' + +def getcoroutinestate(coroutine): + """Get current state of a coroutine object. + + Possible states are: + CORO_CREATED: Waiting to start execution. + CORO_RUNNING: Currently being executed by the interpreter. + CORO_SUSPENDED: Currently suspended at an await expression. + CORO_CLOSED: Execution has completed. + """ + if coroutine.cr_running: + return CORO_RUNNING + if coroutine.cr_frame is None: + return CORO_CLOSED + if coroutine.cr_frame.f_lasti == -1: + return CORO_CREATED + return CORO_SUSPENDED + + +def getcoroutinelocals(coroutine): + """ + Get the mapping of coroutine local variables to their current values. + + A dict is returned, with the keys the local variable names and values the + bound values.""" + frame = getattr(coroutine, "cr_frame", None) + if frame is not None: + return frame.f_locals + else: + return {} + + +############################################################################### +### Function Signature Object (PEP 362) +############################################################################### + + +_WrapperDescriptor = type(type.__call__) +_MethodWrapper = type(all.__call__) +_ClassMethodWrapper = type(int.__dict__['from_bytes']) + +_NonUserDefinedCallables = (_WrapperDescriptor, + _MethodWrapper, + _ClassMethodWrapper, + types.BuiltinFunctionType) + + +def _signature_get_user_defined_method(cls, method_name): + """Private helper. Checks if ``cls`` has an attribute + named ``method_name`` and returns it only if it is a + pure python function. + """ + try: + meth = getattr(cls, method_name) + except AttributeError: + return + else: + if not isinstance(meth, _NonUserDefinedCallables): + # Once '__signature__' will be added to 'C'-level + # callables, this check won't be necessary + return meth + + +def _signature_get_partial(wrapped_sig, partial, extra_args=()): + """Private helper to calculate how 'wrapped_sig' signature will + look like after applying a 'functools.partial' object (or alike) + on it. + """ + + old_params = wrapped_sig.parameters + new_params = OrderedDict(old_params.items()) + + partial_args = partial.args or () + partial_keywords = partial.keywords or {} + + if extra_args: + partial_args = extra_args + partial_args + + try: + ba = wrapped_sig.bind_partial(*partial_args, **partial_keywords) + except TypeError as ex: + msg = 'partial object {!r} has incorrect arguments'.format(partial) + raise ValueError(msg) from ex + + + transform_to_kwonly = False + for param_name, param in old_params.items(): + try: + arg_value = ba.arguments[param_name] + except KeyError: + pass + else: + if param.kind is _POSITIONAL_ONLY: + # If positional-only parameter is bound by partial, + # it effectively disappears from the signature + new_params.pop(param_name) + continue + + if param.kind is _POSITIONAL_OR_KEYWORD: + if param_name in partial_keywords: + # This means that this parameter, and all parameters + # after it should be keyword-only (and var-positional + # should be removed). Here's why. Consider the following + # function: + # foo(a, b, *args, c): + # pass + # + # "partial(foo, a='spam')" will have the following + # signature: "(*, a='spam', b, c)". Because attempting + # to call that partial with "(10, 20)" arguments will + # raise a TypeError, saying that "a" argument received + # multiple values. + transform_to_kwonly = True + # Set the new default value + new_params[param_name] = param.replace(default=arg_value) + else: + # was passed as a positional argument + new_params.pop(param.name) + continue + + if param.kind is _KEYWORD_ONLY: + # Set the new default value + new_params[param_name] = param.replace(default=arg_value) + + if transform_to_kwonly: + assert param.kind is not _POSITIONAL_ONLY + + if param.kind is _POSITIONAL_OR_KEYWORD: + new_param = new_params[param_name].replace(kind=_KEYWORD_ONLY) + new_params[param_name] = new_param + new_params.move_to_end(param_name) + elif param.kind in (_KEYWORD_ONLY, _VAR_KEYWORD): + new_params.move_to_end(param_name) + elif param.kind is _VAR_POSITIONAL: + new_params.pop(param.name) + + return wrapped_sig.replace(parameters=new_params.values()) + + +def _signature_bound_method(sig): + """Private helper to transform signatures for unbound + functions to bound methods. + """ + + params = tuple(sig.parameters.values()) + + if not params or params[0].kind in (_VAR_KEYWORD, _KEYWORD_ONLY): + raise ValueError('invalid method signature') + + kind = params[0].kind + if kind in (_POSITIONAL_OR_KEYWORD, _POSITIONAL_ONLY): + # Drop first parameter: + # '(p1, p2[, ...])' -> '(p2[, ...])' + params = params[1:] + else: + if kind is not _VAR_POSITIONAL: + # Unless we add a new parameter type we never + # get here + raise ValueError('invalid argument type') + # It's a var-positional parameter. + # Do nothing. '(*args[, ...])' -> '(*args[, ...])' + + return sig.replace(parameters=params) + + +def _signature_is_builtin(obj): + """Private helper to test if `obj` is a callable that might + support Argument Clinic's __text_signature__ protocol. + """ + return (isbuiltin(obj) or + ismethoddescriptor(obj) or + isinstance(obj, _NonUserDefinedCallables) or + # Can't test 'isinstance(type)' here, as it would + # also be True for regular python classes + obj in (type, object)) + + +def _signature_is_functionlike(obj): + """Private helper to test if `obj` is a duck type of FunctionType. + A good example of such objects are functions compiled with + Cython, which have all attributes that a pure Python function + would have, but have their code statically compiled. + """ + + if not callable(obj) or isclass(obj): + # All function-like objects are obviously callables, + # and not classes. + return False + + name = getattr(obj, '__name__', None) + code = getattr(obj, '__code__', None) + defaults = getattr(obj, '__defaults__', _void) # Important to use _void ... + kwdefaults = getattr(obj, '__kwdefaults__', _void) # ... and not None here + annotations = getattr(obj, '__annotations__', None) + + return (isinstance(code, types.CodeType) and + isinstance(name, str) and + (defaults is None or isinstance(defaults, tuple)) and + (kwdefaults is None or isinstance(kwdefaults, dict)) and + isinstance(annotations, dict)) + + +def _signature_get_bound_param(spec): + """ Private helper to get first parameter name from a + __text_signature__ of a builtin method, which should + be in the following format: '($param1, ...)'. + Assumptions are that the first argument won't have + a default value or an annotation. + """ + + assert spec.startswith('($') + + pos = spec.find(',') + if pos == -1: + pos = spec.find(')') + + cpos = spec.find(':') + assert cpos == -1 or cpos > pos + + cpos = spec.find('=') + assert cpos == -1 or cpos > pos + + return spec[2:pos] + + +def _signature_strip_non_python_syntax(signature): + """ + Private helper function. Takes a signature in Argument Clinic's + extended signature format. + + Returns a tuple of three things: + * that signature re-rendered in standard Python syntax, + * the index of the "self" parameter (generally 0), or None if + the function does not have a "self" parameter, and + * the index of the last "positional only" parameter, + or None if the signature has no positional-only parameters. + """ + + if not signature: + return signature, None, None + + self_parameter = None + last_positional_only = None + + lines = [l.encode('ascii') for l in signature.split('\n')] + generator = iter(lines).__next__ + token_stream = tokenize.tokenize(generator) + + delayed_comma = False + skip_next_comma = False + text = [] + add = text.append + + current_parameter = 0 + OP = token.OP + ERRORTOKEN = token.ERRORTOKEN + + # token stream always starts with ENCODING token, skip it + t = next(token_stream) + assert t.type == tokenize.ENCODING + + for t in token_stream: + type, string = t.type, t.string + + if type == OP: + if string == ',': + if skip_next_comma: + skip_next_comma = False + else: + assert not delayed_comma + delayed_comma = True + current_parameter += 1 + continue + + if string == '/': + assert not skip_next_comma + assert last_positional_only is None + skip_next_comma = True + last_positional_only = current_parameter - 1 + continue + + if (type == ERRORTOKEN) and (string == '$'): + assert self_parameter is None + self_parameter = current_parameter + continue + + if delayed_comma: + delayed_comma = False + if not ((type == OP) and (string == ')')): + add(', ') + add(string) + if (string == ','): + add(' ') + clean_signature = ''.join(text) + return clean_signature, self_parameter, last_positional_only + + +def _signature_fromstr(cls, obj, s, skip_bound_arg=True): + """Private helper to parse content of '__text_signature__' + and return a Signature based on it. + """ + + Parameter = cls._parameter_cls + + clean_signature, self_parameter, last_positional_only = \ + _signature_strip_non_python_syntax(s) + + program = "def foo" + clean_signature + ": pass" + + try: + module = ast.parse(program) + except SyntaxError: + module = None + + if not isinstance(module, ast.Module): + raise ValueError("{!r} builtin has invalid signature".format(obj)) + + f = module.body[0] + + parameters = [] + empty = Parameter.empty + invalid = object() + + module = None + module_dict = {} + module_name = getattr(obj, '__module__', None) + if module_name: + module = sys.modules.get(module_name, None) + if module: + module_dict = module.__dict__ + sys_module_dict = sys.modules + + def parse_name(node): + assert isinstance(node, ast.arg) + if node.annotation != None: + raise ValueError("Annotations are not currently supported") + return node.arg + + def wrap_value(s): + try: + value = eval(s, module_dict) + except NameError: + try: + value = eval(s, sys_module_dict) + except NameError: + raise RuntimeError() + + if isinstance(value, str): + return ast.Str(value) + if isinstance(value, (int, float)): + return ast.Num(value) + if isinstance(value, bytes): + return ast.Bytes(value) + if value in (True, False, None): + return ast.NameConstant(value) + raise RuntimeError() + + class RewriteSymbolics(ast.NodeTransformer): + def visit_Attribute(self, node): + a = [] + n = node + while isinstance(n, ast.Attribute): + a.append(n.attr) + n = n.value + if not isinstance(n, ast.Name): + raise RuntimeError() + a.append(n.id) + value = ".".join(reversed(a)) + return wrap_value(value) + + def visit_Name(self, node): + if not isinstance(node.ctx, ast.Load): + raise ValueError() + return wrap_value(node.id) + + def p(name_node, default_node, default=empty): + name = parse_name(name_node) + if name is invalid: + return None + if default_node and default_node is not _empty: + try: + default_node = RewriteSymbolics().visit(default_node) + o = ast.literal_eval(default_node) + except ValueError: + o = invalid + if o is invalid: + return None + default = o if o is not invalid else default + parameters.append(Parameter(name, kind, default=default, annotation=empty)) + + # non-keyword-only parameters + args = reversed(f.args.args) + defaults = reversed(f.args.defaults) + iter = itertools.zip_longest(args, defaults, fillvalue=None) + if last_positional_only is not None: + kind = Parameter.POSITIONAL_ONLY + else: + kind = Parameter.POSITIONAL_OR_KEYWORD + for i, (name, default) in enumerate(reversed(list(iter))): + p(name, default) + if i == last_positional_only: + kind = Parameter.POSITIONAL_OR_KEYWORD + + # *args + if f.args.vararg: + kind = Parameter.VAR_POSITIONAL + p(f.args.vararg, empty) + + # keyword-only arguments + kind = Parameter.KEYWORD_ONLY + for name, default in zip(f.args.kwonlyargs, f.args.kw_defaults): + p(name, default) + + # **kwargs + if f.args.kwarg: + kind = Parameter.VAR_KEYWORD + p(f.args.kwarg, empty) + + if self_parameter is not None: + # Possibly strip the bound argument: + # - We *always* strip first bound argument if + # it is a module. + # - We don't strip first bound argument if + # skip_bound_arg is False. + assert parameters + _self = getattr(obj, '__self__', None) + self_isbound = _self is not None + self_ismodule = ismodule(_self) + if self_isbound and (self_ismodule or skip_bound_arg): + parameters.pop(0) + else: + # for builtins, self parameter is always positional-only! + p = parameters[0].replace(kind=Parameter.POSITIONAL_ONLY) + parameters[0] = p + + return cls(parameters, return_annotation=cls.empty) + + +def _signature_from_builtin(cls, func, skip_bound_arg=True): + """Private helper function to get signature for + builtin callables. + """ + + if not _signature_is_builtin(func): + raise TypeError("{!r} is not a Python builtin " + "function".format(func)) + + s = getattr(func, "__text_signature__", None) + if not s: + raise ValueError("no signature found for builtin {!r}".format(func)) + + return _signature_fromstr(cls, func, s, skip_bound_arg) + + +def _signature_from_function(cls, func): + """Private helper: constructs Signature for the given python function.""" + + is_duck_function = False + if not isfunction(func): + if _signature_is_functionlike(func): + is_duck_function = True + else: + # If it's not a pure Python function, and not a duck type + # of pure function: + raise TypeError('{!r} is not a Python function'.format(func)) + + Parameter = cls._parameter_cls + + # Parameter information. + func_code = func.__code__ + pos_count = func_code.co_argcount + arg_names = func_code.co_varnames + positional = tuple(arg_names[:pos_count]) + keyword_only_count = func_code.co_kwonlyargcount + keyword_only = arg_names[pos_count:(pos_count + keyword_only_count)] + annotations = func.__annotations__ + defaults = func.__defaults__ + kwdefaults = func.__kwdefaults__ + + if defaults: + pos_default_count = len(defaults) + else: + pos_default_count = 0 + + parameters = [] + + # Non-keyword-only parameters w/o defaults. + non_default_count = pos_count - pos_default_count + for name in positional[:non_default_count]: + annotation = annotations.get(name, _empty) + parameters.append(Parameter(name, annotation=annotation, + kind=_POSITIONAL_OR_KEYWORD)) + + # ... w/ defaults. + for offset, name in enumerate(positional[non_default_count:]): + annotation = annotations.get(name, _empty) + parameters.append(Parameter(name, annotation=annotation, + kind=_POSITIONAL_OR_KEYWORD, + default=defaults[offset])) + + # *args + if func_code.co_flags & CO_VARARGS: + name = arg_names[pos_count + keyword_only_count] + annotation = annotations.get(name, _empty) + parameters.append(Parameter(name, annotation=annotation, + kind=_VAR_POSITIONAL)) + + # Keyword-only parameters. + for name in keyword_only: + default = _empty + if kwdefaults is not None: + default = kwdefaults.get(name, _empty) + + annotation = annotations.get(name, _empty) + parameters.append(Parameter(name, annotation=annotation, + kind=_KEYWORD_ONLY, + default=default)) + # **kwargs + if func_code.co_flags & CO_VARKEYWORDS: + index = pos_count + keyword_only_count + if func_code.co_flags & CO_VARARGS: + index += 1 + + name = arg_names[index] + annotation = annotations.get(name, _empty) + parameters.append(Parameter(name, annotation=annotation, + kind=_VAR_KEYWORD)) + + # Is 'func' is a pure Python function - don't validate the + # parameters list (for correct order and defaults), it should be OK. + return cls(parameters, + return_annotation=annotations.get('return', _empty), + __validate_parameters__=is_duck_function) + + +def _signature_from_callable(obj, *, + follow_wrapper_chains=True, + skip_bound_arg=True, + sigcls): + + """Private helper function to get signature for arbitrary + callable objects. + """ + + if not callable(obj): + raise TypeError('{!r} is not a callable object'.format(obj)) + + if isinstance(obj, types.MethodType): + # In this case we skip the first parameter of the underlying + # function (usually `self` or `cls`). + sig = _signature_from_callable( + obj.__func__, + follow_wrapper_chains=follow_wrapper_chains, + skip_bound_arg=skip_bound_arg, + sigcls=sigcls) + + if skip_bound_arg: + return _signature_bound_method(sig) + else: + return sig + + # Was this function wrapped by a decorator? + if follow_wrapper_chains: + obj = unwrap(obj, stop=(lambda f: hasattr(f, "__signature__"))) + if isinstance(obj, types.MethodType): + # If the unwrapped object is a *method*, we might want to + # skip its first parameter (self). + # See test_signature_wrapped_bound_method for details. + return _signature_from_callable( + obj, + follow_wrapper_chains=follow_wrapper_chains, + skip_bound_arg=skip_bound_arg, + sigcls=sigcls) + + try: + sig = obj.__signature__ + except AttributeError: + pass + else: + if sig is not None: + if not isinstance(sig, Signature): + raise TypeError( + 'unexpected object {!r} in __signature__ ' + 'attribute'.format(sig)) + return sig + + try: + partialmethod = obj._partialmethod + except AttributeError: + pass + else: + if isinstance(partialmethod, functools.partialmethod): + # Unbound partialmethod (see functools.partialmethod) + # This means, that we need to calculate the signature + # as if it's a regular partial object, but taking into + # account that the first positional argument + # (usually `self`, or `cls`) will not be passed + # automatically (as for boundmethods) + + wrapped_sig = _signature_from_callable( + partialmethod.func, + follow_wrapper_chains=follow_wrapper_chains, + skip_bound_arg=skip_bound_arg, + sigcls=sigcls) + + sig = _signature_get_partial(wrapped_sig, partialmethod, (None,)) + first_wrapped_param = tuple(wrapped_sig.parameters.values())[0] + if first_wrapped_param.kind is Parameter.VAR_POSITIONAL: + # First argument of the wrapped callable is `*args`, as in + # `partialmethod(lambda *args)`. + return sig + else: + sig_params = tuple(sig.parameters.values()) + assert first_wrapped_param is not sig_params[0] + new_params = (first_wrapped_param,) + sig_params + return sig.replace(parameters=new_params) + + if isfunction(obj) or _signature_is_functionlike(obj): + # If it's a pure Python function, or an object that is duck type + # of a Python function (Cython functions, for instance), then: + return _signature_from_function(sigcls, obj) + + if _signature_is_builtin(obj): + return _signature_from_builtin(sigcls, obj, + skip_bound_arg=skip_bound_arg) + + if isinstance(obj, functools.partial): + wrapped_sig = _signature_from_callable( + obj.func, + follow_wrapper_chains=follow_wrapper_chains, + skip_bound_arg=skip_bound_arg, + sigcls=sigcls) + return _signature_get_partial(wrapped_sig, obj) + + sig = None + if isinstance(obj, type): + # obj is a class or a metaclass + + # First, let's see if it has an overloaded __call__ defined + # in its metaclass + call = _signature_get_user_defined_method(type(obj), '__call__') + if call is not None: + sig = _signature_from_callable( + call, + follow_wrapper_chains=follow_wrapper_chains, + skip_bound_arg=skip_bound_arg, + sigcls=sigcls) + else: + # Now we check if the 'obj' class has a '__new__' method + new = _signature_get_user_defined_method(obj, '__new__') + if new is not None: + sig = _signature_from_callable( + new, + follow_wrapper_chains=follow_wrapper_chains, + skip_bound_arg=skip_bound_arg, + sigcls=sigcls) + else: + # Finally, we should have at least __init__ implemented + init = _signature_get_user_defined_method(obj, '__init__') + if init is not None: + sig = _signature_from_callable( + init, + follow_wrapper_chains=follow_wrapper_chains, + skip_bound_arg=skip_bound_arg, + sigcls=sigcls) + + if sig is None: + # At this point we know, that `obj` is a class, with no user- + # defined '__init__', '__new__', or class-level '__call__' + + for base in obj.__mro__[:-1]: + # Since '__text_signature__' is implemented as a + # descriptor that extracts text signature from the + # class docstring, if 'obj' is derived from a builtin + # class, its own '__text_signature__' may be 'None'. + # Therefore, we go through the MRO (except the last + # class in there, which is 'object') to find the first + # class with non-empty text signature. + try: + text_sig = base.__text_signature__ + except AttributeError: + pass + else: + if text_sig: + # If 'obj' class has a __text_signature__ attribute: + # return a signature based on it + return _signature_fromstr(sigcls, obj, text_sig) + + # No '__text_signature__' was found for the 'obj' class. + # Last option is to check if its '__init__' is + # object.__init__ or type.__init__. + if type not in obj.__mro__: + # We have a class (not metaclass), but no user-defined + # __init__ or __new__ for it + if (obj.__init__ is object.__init__ and + obj.__new__ is object.__new__): + # Return a signature of 'object' builtin. + return signature(object) + else: + raise ValueError( + 'no signature found for builtin type {!r}'.format(obj)) + + elif not isinstance(obj, _NonUserDefinedCallables): + # An object with __call__ + # We also check that the 'obj' is not an instance of + # _WrapperDescriptor or _MethodWrapper to avoid + # infinite recursion (and even potential segfault) + call = _signature_get_user_defined_method(type(obj), '__call__') + if call is not None: + try: + sig = _signature_from_callable( + call, + follow_wrapper_chains=follow_wrapper_chains, + skip_bound_arg=skip_bound_arg, + sigcls=sigcls) + except ValueError as ex: + msg = 'no signature found for {!r}'.format(obj) + raise ValueError(msg) from ex + + if sig is not None: + # For classes and objects we skip the first parameter of their + # __call__, __new__, or __init__ methods + if skip_bound_arg: + return _signature_bound_method(sig) + else: + return sig + + if isinstance(obj, types.BuiltinFunctionType): + # Raise a nicer error message for builtins + msg = 'no signature found for builtin function {!r}'.format(obj) + raise ValueError(msg) + + raise ValueError('callable {!r} is not supported by signature'.format(obj)) + + +class _void: + """A private marker - used in Parameter & Signature.""" + + +class _empty: + """Marker object for Signature.empty and Parameter.empty.""" + + +class _ParameterKind(enum.IntEnum): + POSITIONAL_ONLY = 0 + POSITIONAL_OR_KEYWORD = 1 + VAR_POSITIONAL = 2 + KEYWORD_ONLY = 3 + VAR_KEYWORD = 4 + + def __str__(self): + return self._name_ + + +_POSITIONAL_ONLY = _ParameterKind.POSITIONAL_ONLY +_POSITIONAL_OR_KEYWORD = _ParameterKind.POSITIONAL_OR_KEYWORD +_VAR_POSITIONAL = _ParameterKind.VAR_POSITIONAL +_KEYWORD_ONLY = _ParameterKind.KEYWORD_ONLY +_VAR_KEYWORD = _ParameterKind.VAR_KEYWORD + + +class Parameter: + """Represents a parameter in a function signature. + + Has the following public attributes: + + * name : str + The name of the parameter as a string. + * default : object + The default value for the parameter if specified. If the + parameter has no default value, this attribute is set to + `Parameter.empty`. + * annotation + The annotation for the parameter if specified. If the + parameter has no annotation, this attribute is set to + `Parameter.empty`. + * kind : str + Describes how argument values are bound to the parameter. + Possible values: `Parameter.POSITIONAL_ONLY`, + `Parameter.POSITIONAL_OR_KEYWORD`, `Parameter.VAR_POSITIONAL`, + `Parameter.KEYWORD_ONLY`, `Parameter.VAR_KEYWORD`. + """ + + __slots__ = ('_name', '_kind', '_default', '_annotation') + + POSITIONAL_ONLY = _POSITIONAL_ONLY + POSITIONAL_OR_KEYWORD = _POSITIONAL_OR_KEYWORD + VAR_POSITIONAL = _VAR_POSITIONAL + KEYWORD_ONLY = _KEYWORD_ONLY + VAR_KEYWORD = _VAR_KEYWORD + + empty = _empty + + def __init__(self, name, kind, *, default=_empty, annotation=_empty): + + if kind not in (_POSITIONAL_ONLY, _POSITIONAL_OR_KEYWORD, + _VAR_POSITIONAL, _KEYWORD_ONLY, _VAR_KEYWORD): + raise ValueError("invalid value for 'Parameter.kind' attribute") + self._kind = kind + + if default is not _empty: + if kind in (_VAR_POSITIONAL, _VAR_KEYWORD): + msg = '{} parameters cannot have default values'.format(kind) + raise ValueError(msg) + self._default = default + self._annotation = annotation + + if name is _empty: + raise ValueError('name is a required attribute for Parameter') + + if not isinstance(name, str): + raise TypeError("name must be a str, not a {!r}".format(name)) + + if name[0] == '.' and name[1:].isdigit(): + # These are implicit arguments generated by comprehensions. In + # order to provide a friendlier interface to users, we recast + # their name as "implicitN" and treat them as positional-only. + # See issue 19611. + if kind != _POSITIONAL_OR_KEYWORD: + raise ValueError( + 'implicit arguments must be passed in as {}'.format( + _POSITIONAL_OR_KEYWORD + ) + ) + self._kind = _POSITIONAL_ONLY + name = 'implicit{}'.format(name[1:]) + + if not name.isidentifier(): + raise ValueError('{!r} is not a valid parameter name'.format(name)) + + self._name = name + + def __reduce__(self): + return (type(self), + (self._name, self._kind), + {'_default': self._default, + '_annotation': self._annotation}) + + def __setstate__(self, state): + self._default = state['_default'] + self._annotation = state['_annotation'] + + @property + def name(self): + return self._name + + @property + def default(self): + return self._default + + @property + def annotation(self): + return self._annotation + + @property + def kind(self): + return self._kind + + def replace(self, *, name=_void, kind=_void, + annotation=_void, default=_void): + """Creates a customized copy of the Parameter.""" + + if name is _void: + name = self._name + + if kind is _void: + kind = self._kind + + if annotation is _void: + annotation = self._annotation + + if default is _void: + default = self._default + + return type(self)(name, kind, default=default, annotation=annotation) + + def __str__(self): + kind = self.kind + formatted = self._name + + # Add annotation and default value + if self._annotation is not _empty: + formatted = '{}:{}'.format(formatted, + formatannotation(self._annotation)) + + if self._default is not _empty: + formatted = '{}={}'.format(formatted, repr(self._default)) + + if kind == _VAR_POSITIONAL: + formatted = '*' + formatted + elif kind == _VAR_KEYWORD: + formatted = '**' + formatted + + return formatted + + def __repr__(self): + return '<{} "{}">'.format(self.__class__.__name__, self) + + def __hash__(self): + return hash((self.name, self.kind, self.annotation, self.default)) + + def __eq__(self, other): + if self is other: + return True + if not isinstance(other, Parameter): + return NotImplemented + return (self._name == other._name and + self._kind == other._kind and + self._default == other._default and + self._annotation == other._annotation) + + +class BoundArguments: + """Result of `Signature.bind` call. Holds the mapping of arguments + to the function's parameters. + + Has the following public attributes: + + * arguments : OrderedDict + An ordered mutable mapping of parameters' names to arguments' values. + Does not contain arguments' default values. + * signature : Signature + The Signature object that created this instance. + * args : tuple + Tuple of positional arguments values. + * kwargs : dict + Dict of keyword arguments values. + """ + + __slots__ = ('arguments', '_signature', '__weakref__') + + def __init__(self, signature, arguments): + self.arguments = arguments + self._signature = signature + + @property + def signature(self): + return self._signature + + @property + def args(self): + args = [] + for param_name, param in self._signature.parameters.items(): + if param.kind in (_VAR_KEYWORD, _KEYWORD_ONLY): + break + + try: + arg = self.arguments[param_name] + except KeyError: + # We're done here. Other arguments + # will be mapped in 'BoundArguments.kwargs' + break + else: + if param.kind == _VAR_POSITIONAL: + # *args + args.extend(arg) + else: + # plain argument + args.append(arg) + + return tuple(args) + + @property + def kwargs(self): + kwargs = {} + kwargs_started = False + for param_name, param in self._signature.parameters.items(): + if not kwargs_started: + if param.kind in (_VAR_KEYWORD, _KEYWORD_ONLY): + kwargs_started = True + else: + if param_name not in self.arguments: + kwargs_started = True + continue + + if not kwargs_started: + continue + + try: + arg = self.arguments[param_name] + except KeyError: + pass + else: + if param.kind == _VAR_KEYWORD: + # **kwargs + kwargs.update(arg) + else: + # plain keyword argument + kwargs[param_name] = arg + + return kwargs + + def apply_defaults(self): + """Set default values for missing arguments. + + For variable-positional arguments (*args) the default is an + empty tuple. + + For variable-keyword arguments (**kwargs) the default is an + empty dict. + """ + arguments = self.arguments + new_arguments = [] + for name, param in self._signature.parameters.items(): + try: + new_arguments.append((name, arguments[name])) + except KeyError: + if param.default is not _empty: + val = param.default + elif param.kind is _VAR_POSITIONAL: + val = () + elif param.kind is _VAR_KEYWORD: + val = {} + else: + # This BoundArguments was likely produced by + # Signature.bind_partial(). + continue + new_arguments.append((name, val)) + self.arguments = OrderedDict(new_arguments) + + def __eq__(self, other): + if self is other: + return True + if not isinstance(other, BoundArguments): + return NotImplemented + return (self.signature == other.signature and + self.arguments == other.arguments) + + def __setstate__(self, state): + self._signature = state['_signature'] + self.arguments = state['arguments'] + + def __getstate__(self): + return {'_signature': self._signature, 'arguments': self.arguments} + + def __repr__(self): + args = [] + for arg, value in self.arguments.items(): + args.append('{}={!r}'.format(arg, value)) + return '<{} ({})>'.format(self.__class__.__name__, ', '.join(args)) + + +class Signature: + """A Signature object represents the overall signature of a function. + It stores a Parameter object for each parameter accepted by the + function, as well as information specific to the function itself. + + A Signature object has the following public attributes and methods: + + * parameters : OrderedDict + An ordered mapping of parameters' names to the corresponding + Parameter objects (keyword-only arguments are in the same order + as listed in `code.co_varnames`). + * return_annotation : object + The annotation for the return type of the function if specified. + If the function has no annotation for its return type, this + attribute is set to `Signature.empty`. + * bind(*args, **kwargs) -> BoundArguments + Creates a mapping from positional and keyword arguments to + parameters. + * bind_partial(*args, **kwargs) -> BoundArguments + Creates a partial mapping from positional and keyword arguments + to parameters (simulating 'functools.partial' behavior.) + """ + + __slots__ = ('_return_annotation', '_parameters') + + _parameter_cls = Parameter + _bound_arguments_cls = BoundArguments + + empty = _empty + + def __init__(self, parameters=None, *, return_annotation=_empty, + __validate_parameters__=True): + """Constructs Signature from the given list of Parameter + objects and 'return_annotation'. All arguments are optional. + """ + + if parameters is None: + params = OrderedDict() + else: + if __validate_parameters__: + params = OrderedDict() + top_kind = _POSITIONAL_ONLY + kind_defaults = False + + for idx, param in enumerate(parameters): + kind = param.kind + name = param.name + + if kind < top_kind: + msg = 'wrong parameter order: {!r} before {!r}' + msg = msg.format(top_kind, kind) + raise ValueError(msg) + elif kind > top_kind: + kind_defaults = False + top_kind = kind + + if kind in (_POSITIONAL_ONLY, _POSITIONAL_OR_KEYWORD): + if param.default is _empty: + if kind_defaults: + # No default for this parameter, but the + # previous parameter of the same kind had + # a default + msg = 'non-default argument follows default ' \ + 'argument' + raise ValueError(msg) + else: + # There is a default for this parameter. + kind_defaults = True + + if name in params: + msg = 'duplicate parameter name: {!r}'.format(name) + raise ValueError(msg) + + params[name] = param + else: + params = OrderedDict(((param.name, param) + for param in parameters)) + + self._parameters = types.MappingProxyType(params) + self._return_annotation = return_annotation + + @classmethod + def from_function(cls, func): + """Constructs Signature for the given python function.""" + + warnings.warn("inspect.Signature.from_function() is deprecated, " + "use Signature.from_callable()", + DeprecationWarning, stacklevel=2) + return _signature_from_function(cls, func) + + @classmethod + def from_builtin(cls, func): + """Constructs Signature for the given builtin function.""" + + warnings.warn("inspect.Signature.from_builtin() is deprecated, " + "use Signature.from_callable()", + DeprecationWarning, stacklevel=2) + return _signature_from_builtin(cls, func) + + @classmethod + def from_callable(cls, obj, *, follow_wrapped=True): + """Constructs Signature for the given callable object.""" + return _signature_from_callable(obj, sigcls=cls, + follow_wrapper_chains=follow_wrapped) + + @property + def parameters(self): + return self._parameters + + @property + def return_annotation(self): + return self._return_annotation + + def replace(self, *, parameters=_void, return_annotation=_void): + """Creates a customized copy of the Signature. + Pass 'parameters' and/or 'return_annotation' arguments + to override them in the new copy. + """ + + if parameters is _void: + parameters = self.parameters.values() + + if return_annotation is _void: + return_annotation = self._return_annotation + + return type(self)(parameters, + return_annotation=return_annotation) + + def _hash_basis(self): + params = tuple(param for param in self.parameters.values() + if param.kind != _KEYWORD_ONLY) + + kwo_params = {param.name: param for param in self.parameters.values() + if param.kind == _KEYWORD_ONLY} + + return params, kwo_params, self.return_annotation + + def __hash__(self): + params, kwo_params, return_annotation = self._hash_basis() + kwo_params = frozenset(kwo_params.values()) + return hash((params, kwo_params, return_annotation)) + + def __eq__(self, other): + if self is other: + return True + if not isinstance(other, Signature): + return NotImplemented + return self._hash_basis() == other._hash_basis() + + def _bind(self, args, kwargs, *, partial=False): + """Private method. Don't use directly.""" + + arguments = OrderedDict() + + parameters = iter(self.parameters.values()) + parameters_ex = () + arg_vals = iter(args) + + while True: + # Let's iterate through the positional arguments and corresponding + # parameters + try: + arg_val = next(arg_vals) + except StopIteration: + # No more positional arguments + try: + param = next(parameters) + except StopIteration: + # No more parameters. That's it. Just need to check that + # we have no `kwargs` after this while loop + break + else: + if param.kind == _VAR_POSITIONAL: + # That's OK, just empty *args. Let's start parsing + # kwargs + break + elif param.name in kwargs: + if param.kind == _POSITIONAL_ONLY: + msg = '{arg!r} parameter is positional only, ' \ + 'but was passed as a keyword' + msg = msg.format(arg=param.name) + raise TypeError(msg) from None + parameters_ex = (param,) + break + elif (param.kind == _VAR_KEYWORD or + param.default is not _empty): + # That's fine too - we have a default value for this + # parameter. So, lets start parsing `kwargs`, starting + # with the current parameter + parameters_ex = (param,) + break + else: + # No default, not VAR_KEYWORD, not VAR_POSITIONAL, + # not in `kwargs` + if partial: + parameters_ex = (param,) + break + else: + msg = 'missing a required argument: {arg!r}' + msg = msg.format(arg=param.name) + raise TypeError(msg) from None + else: + # We have a positional argument to process + try: + param = next(parameters) + except StopIteration: + raise TypeError('too many positional arguments') from None + else: + if param.kind in (_VAR_KEYWORD, _KEYWORD_ONLY): + # Looks like we have no parameter for this positional + # argument + raise TypeError( + 'too many positional arguments') from None + + if param.kind == _VAR_POSITIONAL: + # We have an '*args'-like argument, let's fill it with + # all positional arguments we have left and move on to + # the next phase + values = [arg_val] + values.extend(arg_vals) + arguments[param.name] = tuple(values) + break + + if param.name in kwargs: + raise TypeError( + 'multiple values for argument {arg!r}'.format( + arg=param.name)) from None + + arguments[param.name] = arg_val + + # Now, we iterate through the remaining parameters to process + # keyword arguments + kwargs_param = None + for param in itertools.chain(parameters_ex, parameters): + if param.kind == _VAR_KEYWORD: + # Memorize that we have a '**kwargs'-like parameter + kwargs_param = param + continue + + if param.kind == _VAR_POSITIONAL: + # Named arguments don't refer to '*args'-like parameters. + # We only arrive here if the positional arguments ended + # before reaching the last parameter before *args. + continue + + param_name = param.name + try: + arg_val = kwargs.pop(param_name) + except KeyError: + # We have no value for this parameter. It's fine though, + # if it has a default value, or it is an '*args'-like + # parameter, left alone by the processing of positional + # arguments. + if (not partial and param.kind != _VAR_POSITIONAL and + param.default is _empty): + raise TypeError('missing a required argument: {arg!r}'. \ + format(arg=param_name)) from None + + else: + if param.kind == _POSITIONAL_ONLY: + # This should never happen in case of a properly built + # Signature object (but let's have this check here + # to ensure correct behavior 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() |