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Diffstat (limited to 'venv/Lib/site-packages/astroid/interpreter/objectmodel.py')
| -rw-r--r-- | venv/Lib/site-packages/astroid/interpreter/objectmodel.py | 738 |
1 files changed, 738 insertions, 0 deletions
diff --git a/venv/Lib/site-packages/astroid/interpreter/objectmodel.py b/venv/Lib/site-packages/astroid/interpreter/objectmodel.py new file mode 100644 index 0000000..5e488d9 --- /dev/null +++ b/venv/Lib/site-packages/astroid/interpreter/objectmodel.py @@ -0,0 +1,738 @@ +# Copyright (c) 2016-2018 Claudiu Popa <pcmanticore@gmail.com> +# Copyright (c) 2016 Derek Gustafson <degustaf@gmail.com> +# Copyright (c) 2017-2018 Bryce Guinta <bryce.paul.guinta@gmail.com> +# Copyright (c) 2017 Ceridwen <ceridwenv@gmail.com> +# Copyright (c) 2017 Calen Pennington <cale@edx.org> +# Copyright (c) 2018 Nick Drozd <nicholasdrozd@gmail.com> +# Licensed under the LGPL: https://www.gnu.org/licenses/old-licenses/lgpl-2.1.en.html +# For details: https://github.com/PyCQA/astroid/blob/master/COPYING.LESSER +""" +Data object model, as per https://docs.python.org/3/reference/datamodel.html. + +This module describes, at least partially, a data object model for some +of astroid's nodes. The model contains special attributes that nodes such +as functions, classes, modules etc have, such as __doc__, __class__, +__module__ etc, being used when doing attribute lookups over nodes. + +For instance, inferring `obj.__class__` will first trigger an inference +of the `obj` variable. If it was successfully inferred, then an attribute +`__class__ will be looked for in the inferred object. This is the part +where the data model occurs. The model is attached to those nodes +and the lookup mechanism will try to see if attributes such as +`__class__` are defined by the model or not. If they are defined, +the model will be requested to return the corresponding value of that +attribute. Thus the model can be viewed as a special part of the lookup +mechanism. +""" + +import itertools +import pprint +import os +import types +from functools import lru_cache + +import astroid +from astroid import context as contextmod +from astroid import exceptions +from astroid import node_classes + + +IMPL_PREFIX = "attr_" + + +def _dunder_dict(instance, attributes): + obj = node_classes.Dict(parent=instance) + + # Convert the keys to node strings + keys = [ + node_classes.Const(value=value, parent=obj) for value in list(attributes.keys()) + ] + + # The original attribute has a list of elements for each key, + # but that is not useful for retrieving the special attribute's value. + # In this case, we're picking the last value from each list. + values = [elem[-1] for elem in attributes.values()] + + obj.postinit(list(zip(keys, values))) + return obj + + +class ObjectModel: + def __init__(self): + self._instance = None + + def __repr__(self): + result = [] + cname = type(self).__name__ + string = "%(cname)s(%(fields)s)" + alignment = len(cname) + 1 + for field in sorted(self.attributes()): + width = 80 - len(field) - alignment + lines = pprint.pformat(field, indent=2, width=width).splitlines(True) + + inner = [lines[0]] + for line in lines[1:]: + inner.append(" " * alignment + line) + result.append(field) + + return string % { + "cname": cname, + "fields": (",\n" + " " * alignment).join(result), + } + + def __call__(self, instance): + self._instance = instance + return self + + def __get__(self, instance, cls=None): + # ObjectModel needs to be a descriptor so that just doing + # `special_attributes = SomeObjectModel` should be enough in the body of a node. + # But at the same time, node.special_attributes should return an object + # which can be used for manipulating the special attributes. That's the reason + # we pass the instance through which it got accessed to ObjectModel.__call__, + # returning itself afterwards, so we can still have access to the + # underlying data model and to the instance for which it got accessed. + return self(instance) + + def __contains__(self, name): + return name in self.attributes() + + @lru_cache(maxsize=None) + def attributes(self): + """Get the attributes which are exported by this object model.""" + return [ + obj[len(IMPL_PREFIX) :] for obj in dir(self) if obj.startswith(IMPL_PREFIX) + ] + + def lookup(self, name): + """Look up the given *name* in the current model + + It should return an AST or an interpreter object, + but if the name is not found, then an AttributeInferenceError will be raised. + """ + + if name in self.attributes(): + return getattr(self, IMPL_PREFIX + name) + raise exceptions.AttributeInferenceError(target=self._instance, attribute=name) + + +class ModuleModel(ObjectModel): + def _builtins(self): + builtins_ast_module = astroid.MANAGER.builtins_module + return builtins_ast_module.special_attributes.lookup("__dict__") + + @property + def attr_builtins(self): + return self._builtins() + + @property + def attr___path__(self): + if not self._instance.package: + raise exceptions.AttributeInferenceError( + target=self._instance, attribute="__path__" + ) + + path_objs = [ + node_classes.Const( + value=path + if not path.endswith("__init__.py") + else os.path.dirname(path), + parent=self._instance, + ) + for path in self._instance.path + ] + + container = node_classes.List(parent=self._instance) + container.postinit(path_objs) + + return container + + @property + def attr___name__(self): + return node_classes.Const(value=self._instance.name, parent=self._instance) + + @property + def attr___doc__(self): + return node_classes.Const(value=self._instance.doc, parent=self._instance) + + @property + def attr___file__(self): + return node_classes.Const(value=self._instance.file, parent=self._instance) + + @property + def attr___dict__(self): + return _dunder_dict(self._instance, self._instance.globals) + + @property + def attr___package__(self): + if not self._instance.package: + value = "" + else: + value = self._instance.name + + return node_classes.Const(value=value, parent=self._instance) + + # These are related to the Python 3 implementation of the + # import system, + # https://docs.python.org/3/reference/import.html#import-related-module-attributes + + @property + def attr___spec__(self): + # No handling for now. + return node_classes.Unknown() + + @property + def attr___loader__(self): + # No handling for now. + return node_classes.Unknown() + + @property + def attr___cached__(self): + # No handling for now. + return node_classes.Unknown() + + +class FunctionModel(ObjectModel): + @property + def attr___name__(self): + return node_classes.Const(value=self._instance.name, parent=self._instance) + + @property + def attr___doc__(self): + return node_classes.Const(value=self._instance.doc, parent=self._instance) + + @property + def attr___qualname__(self): + return node_classes.Const(value=self._instance.qname(), parent=self._instance) + + @property + def attr___defaults__(self): + func = self._instance + if not func.args.defaults: + return node_classes.Const(value=None, parent=func) + + defaults_obj = node_classes.Tuple(parent=func) + defaults_obj.postinit(func.args.defaults) + return defaults_obj + + @property + def attr___annotations__(self): + obj = node_classes.Dict(parent=self._instance) + + if not self._instance.returns: + returns = None + else: + returns = self._instance.returns + + args = self._instance.args + pair_annotations = itertools.chain( + zip(args.args or [], args.annotations), + zip(args.kwonlyargs, args.kwonlyargs_annotations), + zip(args.posonlyargs or [], args.posonlyargs_annotations), + ) + + annotations = { + arg.name: annotation for (arg, annotation) in pair_annotations if annotation + } + if args.varargannotation: + annotations[args.vararg] = args.varargannotation + if args.kwargannotation: + annotations[args.kwarg] = args.kwargannotation + if returns: + annotations["return"] = returns + + items = [ + (node_classes.Const(key, parent=obj), value) + for (key, value) in annotations.items() + ] + + obj.postinit(items) + return obj + + @property + def attr___dict__(self): + return node_classes.Dict(parent=self._instance) + + attr___globals__ = attr___dict__ + + @property + def attr___kwdefaults__(self): + def _default_args(args, parent): + for arg in args.kwonlyargs: + try: + default = args.default_value(arg.name) + except exceptions.NoDefault: + continue + + name = node_classes.Const(arg.name, parent=parent) + yield name, default + + args = self._instance.args + obj = node_classes.Dict(parent=self._instance) + defaults = dict(_default_args(args, obj)) + + obj.postinit(list(defaults.items())) + return obj + + @property + def attr___module__(self): + return node_classes.Const(self._instance.root().qname()) + + @property + def attr___get__(self): + # pylint: disable=import-outside-toplevel; circular import + from astroid import bases + + func = self._instance + + class DescriptorBoundMethod(bases.BoundMethod): + """Bound method which knows how to understand calling descriptor binding.""" + + def implicit_parameters(self): + # Different than BoundMethod since the signature + # is different. + return 0 + + def infer_call_result(self, caller, context=None): + if len(caller.args) > 2 or len(caller.args) < 1: + raise exceptions.InferenceError( + "Invalid arguments for descriptor binding", + target=self, + context=context, + ) + + context = contextmod.copy_context(context) + cls = next(caller.args[0].infer(context=context)) + + if cls is astroid.Uninferable: + raise exceptions.InferenceError( + "Invalid class inferred", target=self, context=context + ) + + # For some reason func is a Node that the below + # code is not expecting + if isinstance(func, bases.BoundMethod): + yield func + return + + # Rebuild the original value, but with the parent set as the + # class where it will be bound. + new_func = func.__class__( + name=func.name, + doc=func.doc, + lineno=func.lineno, + col_offset=func.col_offset, + parent=cls, + ) + # pylint: disable=no-member + new_func.postinit(func.args, func.body, func.decorators, func.returns) + + # Build a proper bound method that points to our newly built function. + proxy = bases.UnboundMethod(new_func) + yield bases.BoundMethod(proxy=proxy, bound=cls) + + @property + def args(self): + """Overwrite the underlying args to match those of the underlying func + + Usually the underlying *func* is a function/method, as in: + + def test(self): + pass + + This has only the *self* parameter but when we access test.__get__ + we get a new object which has two parameters, *self* and *type*. + """ + nonlocal func + positional_or_keyword_params = func.args.args.copy() + positional_or_keyword_params.append(astroid.AssignName(name="type")) + + positional_only_params = func.args.posonlyargs.copy() + + arguments = astroid.Arguments(parent=func.args.parent) + arguments.postinit( + args=positional_or_keyword_params, + posonlyargs=positional_only_params, + defaults=[], + kwonlyargs=[], + kw_defaults=[], + annotations=[], + ) + return arguments + + return DescriptorBoundMethod(proxy=self._instance, bound=self._instance) + + # These are here just for completion. + @property + def attr___ne__(self): + return node_classes.Unknown() + + attr___subclasshook__ = attr___ne__ + attr___str__ = attr___ne__ + attr___sizeof__ = attr___ne__ + attr___setattr___ = attr___ne__ + attr___repr__ = attr___ne__ + attr___reduce__ = attr___ne__ + attr___reduce_ex__ = attr___ne__ + attr___new__ = attr___ne__ + attr___lt__ = attr___ne__ + attr___eq__ = attr___ne__ + attr___gt__ = attr___ne__ + attr___format__ = attr___ne__ + attr___delattr___ = attr___ne__ + attr___getattribute__ = attr___ne__ + attr___hash__ = attr___ne__ + attr___init__ = attr___ne__ + attr___dir__ = attr___ne__ + attr___call__ = attr___ne__ + attr___class__ = attr___ne__ + attr___closure__ = attr___ne__ + attr___code__ = attr___ne__ + + +class ClassModel(ObjectModel): + @property + def attr___module__(self): + return node_classes.Const(self._instance.root().qname()) + + @property + def attr___name__(self): + return node_classes.Const(self._instance.name) + + @property + def attr___qualname__(self): + return node_classes.Const(self._instance.qname()) + + @property + def attr___doc__(self): + return node_classes.Const(self._instance.doc) + + @property + def attr___mro__(self): + if not self._instance.newstyle: + raise exceptions.AttributeInferenceError( + target=self._instance, attribute="__mro__" + ) + + mro = self._instance.mro() + obj = node_classes.Tuple(parent=self._instance) + obj.postinit(mro) + return obj + + @property + def attr_mro(self): + if not self._instance.newstyle: + raise exceptions.AttributeInferenceError( + target=self._instance, attribute="mro" + ) + + # pylint: disable=import-outside-toplevel; circular import + from astroid import bases + + other_self = self + + # Cls.mro is a method and we need to return one in order to have a proper inference. + # The method we're returning is capable of inferring the underlying MRO though. + class MroBoundMethod(bases.BoundMethod): + def infer_call_result(self, caller, context=None): + yield other_self.attr___mro__ + + implicit_metaclass = self._instance.implicit_metaclass() + mro_method = implicit_metaclass.locals["mro"][0] + return MroBoundMethod(proxy=mro_method, bound=implicit_metaclass) + + @property + def attr___bases__(self): + obj = node_classes.Tuple() + context = contextmod.InferenceContext() + elts = list(self._instance._inferred_bases(context)) + obj.postinit(elts=elts) + return obj + + @property + def attr___class__(self): + # pylint: disable=import-outside-toplevel; circular import + from astroid import helpers + + return helpers.object_type(self._instance) + + @property + def attr___subclasses__(self): + """Get the subclasses of the underlying class + + This looks only in the current module for retrieving the subclasses, + thus it might miss a couple of them. + """ + # pylint: disable=import-outside-toplevel; circular import + from astroid import bases + from astroid import scoped_nodes + + if not self._instance.newstyle: + raise exceptions.AttributeInferenceError( + target=self._instance, attribute="__subclasses__" + ) + + qname = self._instance.qname() + root = self._instance.root() + classes = [ + cls + for cls in root.nodes_of_class(scoped_nodes.ClassDef) + if cls != self._instance and cls.is_subtype_of(qname) + ] + + obj = node_classes.List(parent=self._instance) + obj.postinit(classes) + + class SubclassesBoundMethod(bases.BoundMethod): + def infer_call_result(self, caller, context=None): + yield obj + + implicit_metaclass = self._instance.implicit_metaclass() + subclasses_method = implicit_metaclass.locals["__subclasses__"][0] + return SubclassesBoundMethod(proxy=subclasses_method, bound=implicit_metaclass) + + @property + def attr___dict__(self): + return node_classes.Dict(parent=self._instance) + + +class SuperModel(ObjectModel): + @property + def attr___thisclass__(self): + return self._instance.mro_pointer + + @property + def attr___self_class__(self): + return self._instance._self_class + + @property + def attr___self__(self): + return self._instance.type + + @property + def attr___class__(self): + return self._instance._proxied + + +class UnboundMethodModel(ObjectModel): + @property + def attr___class__(self): + # pylint: disable=import-outside-toplevel; circular import + from astroid import helpers + + return helpers.object_type(self._instance) + + @property + def attr___func__(self): + return self._instance._proxied + + @property + def attr___self__(self): + return node_classes.Const(value=None, parent=self._instance) + + attr_im_func = attr___func__ + attr_im_class = attr___class__ + attr_im_self = attr___self__ + + +class BoundMethodModel(FunctionModel): + @property + def attr___func__(self): + return self._instance._proxied._proxied + + @property + def attr___self__(self): + return self._instance.bound + + +class GeneratorModel(FunctionModel): + def __new__(cls, *args, **kwargs): + # Append the values from the GeneratorType unto this object. + ret = super(GeneratorModel, cls).__new__(cls, *args, **kwargs) + generator = astroid.MANAGER.builtins_module["generator"] + for name, values in generator.locals.items(): + method = values[0] + patched = lambda cls, meth=method: meth + + setattr(type(ret), IMPL_PREFIX + name, property(patched)) + + return ret + + @property + def attr___name__(self): + return node_classes.Const( + value=self._instance.parent.name, parent=self._instance + ) + + @property + def attr___doc__(self): + return node_classes.Const( + value=self._instance.parent.doc, parent=self._instance + ) + + +class AsyncGeneratorModel(GeneratorModel): + def __new__(cls, *args, **kwargs): + # Append the values from the AGeneratorType unto this object. + ret = super().__new__(cls, *args, **kwargs) + astroid_builtins = astroid.MANAGER.builtins_module + generator = astroid_builtins.get("async_generator") + if generator is None: + # Make it backward compatible. + generator = astroid_builtins.get("generator") + + for name, values in generator.locals.items(): + method = values[0] + patched = lambda cls, meth=method: meth + + setattr(type(ret), IMPL_PREFIX + name, property(patched)) + + return ret + + +class InstanceModel(ObjectModel): + @property + def attr___class__(self): + return self._instance._proxied + + @property + def attr___module__(self): + return node_classes.Const(self._instance.root().qname()) + + @property + def attr___doc__(self): + return node_classes.Const(self._instance.doc) + + @property + def attr___dict__(self): + return _dunder_dict(self._instance, self._instance.instance_attrs) + + +# Exception instances + + +class ExceptionInstanceModel(InstanceModel): + @property + def attr_args(self): + message = node_classes.Const("") + args = node_classes.Tuple(parent=self._instance) + args.postinit((message,)) + return args + + @property + def attr___traceback__(self): + builtins_ast_module = astroid.MANAGER.builtins_module + traceback_type = builtins_ast_module[types.TracebackType.__name__] + return traceback_type.instantiate_class() + + +class SyntaxErrorInstanceModel(ExceptionInstanceModel): + @property + def attr_text(self): + return node_classes.Const("") + + +class OSErrorInstanceModel(ExceptionInstanceModel): + @property + def attr_filename(self): + return node_classes.Const("") + + @property + def attr_errno(self): + return node_classes.Const(0) + + @property + def attr_strerror(self): + return node_classes.Const("") + + attr_filename2 = attr_filename + + +class ImportErrorInstanceModel(ExceptionInstanceModel): + @property + def attr_name(self): + return node_classes.Const("") + + @property + def attr_path(self): + return node_classes.Const("") + + +BUILTIN_EXCEPTIONS = { + "builtins.SyntaxError": SyntaxErrorInstanceModel, + "builtins.ImportError": ImportErrorInstanceModel, + # These are all similar to OSError in terms of attributes + "builtins.OSError": OSErrorInstanceModel, + "builtins.BlockingIOError": OSErrorInstanceModel, + "builtins.BrokenPipeError": OSErrorInstanceModel, + "builtins.ChildProcessError": OSErrorInstanceModel, + "builtins.ConnectionAbortedError": OSErrorInstanceModel, + "builtins.ConnectionError": OSErrorInstanceModel, + "builtins.ConnectionRefusedError": OSErrorInstanceModel, + "builtins.ConnectionResetError": OSErrorInstanceModel, + "builtins.FileExistsError": OSErrorInstanceModel, + "builtins.FileNotFoundError": OSErrorInstanceModel, + "builtins.InterruptedError": OSErrorInstanceModel, + "builtins.IsADirectoryError": OSErrorInstanceModel, + "builtins.NotADirectoryError": OSErrorInstanceModel, + "builtins.PermissionError": OSErrorInstanceModel, + "builtins.ProcessLookupError": OSErrorInstanceModel, + "builtins.TimeoutError": OSErrorInstanceModel, +} + + +class DictModel(ObjectModel): + @property + def attr___class__(self): + return self._instance._proxied + + def _generic_dict_attribute(self, obj, name): + """Generate a bound method that can infer the given *obj*.""" + + class DictMethodBoundMethod(astroid.BoundMethod): + def infer_call_result(self, caller, context=None): + yield obj + + meth = next(self._instance._proxied.igetattr(name)) + return DictMethodBoundMethod(proxy=meth, bound=self._instance) + + @property + def attr_items(self): + elems = [] + obj = node_classes.List(parent=self._instance) + for key, value in self._instance.items: + elem = node_classes.Tuple(parent=obj) + elem.postinit((key, value)) + elems.append(elem) + obj.postinit(elts=elems) + + # pylint: disable=import-outside-toplevel; circular import + from astroid import objects + + obj = objects.DictItems(obj) + return self._generic_dict_attribute(obj, "items") + + @property + def attr_keys(self): + keys = [key for (key, _) in self._instance.items] + obj = node_classes.List(parent=self._instance) + obj.postinit(elts=keys) + + # pylint: disable=import-outside-toplevel; circular import + from astroid import objects + + obj = objects.DictKeys(obj) + return self._generic_dict_attribute(obj, "keys") + + @property + def attr_values(self): + + values = [value for (_, value) in self._instance.items] + obj = node_classes.List(parent=self._instance) + obj.postinit(values) + + # pylint: disable=import-outside-toplevel; circular import + from astroid import objects + + obj = objects.DictValues(obj) + return self._generic_dict_attribute(obj, "values") |