# Copyright (c) 2006-2011, 2013-2014 LOGILAB S.A. (Paris, FRANCE) # Copyright (c) 2014-2019 Claudiu Popa # Copyright (c) 2014 BioGeek # Copyright (c) 2014 Google, Inc. # Copyright (c) 2014 Eevee (Alex Munroe) # Copyright (c) 2015-2016 Ceridwen # Copyright (c) 2016 Derek Gustafson # Copyright (c) 2017 Iva Miholic # Copyright (c) 2018 Bryce Guinta # Copyright (c) 2018 Nick Drozd # Copyright (c) 2019 Raphael Gaschignard # Copyright (c) 2020 Anubhav <35621759+anubh-v@users.noreply.github.com> # Copyright (c) 2020 Ashley Whetter # 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 """astroid manager: avoid multiple astroid build of a same module when possible by providing a class responsible to get astroid representation from various source and using a cache of built modules) """ import os import zipimport from astroid import exceptions from astroid.interpreter._import import spec from astroid import modutils from astroid import transforms ZIP_IMPORT_EXTS = (".zip", ".egg", ".whl") def safe_repr(obj): try: return repr(obj) except Exception: # pylint: disable=broad-except return "???" class AstroidManager: """the astroid manager, responsible to build astroid from files or modules. Use the Borg pattern. """ name = "astroid loader" brain = {} def __init__(self): self.__dict__ = AstroidManager.brain if not self.__dict__: # NOTE: cache entries are added by the [re]builder self.astroid_cache = {} self._mod_file_cache = {} self._failed_import_hooks = [] self.always_load_extensions = False self.optimize_ast = False self.extension_package_whitelist = set() self._transform = transforms.TransformVisitor() # Export these APIs for convenience self.register_transform = self._transform.register_transform self.unregister_transform = self._transform.unregister_transform self.max_inferable_values = 100 @property def builtins_module(self): return self.astroid_cache["builtins"] def visit_transforms(self, node): """Visit the transforms and apply them to the given *node*.""" return self._transform.visit(node) def ast_from_file(self, filepath, modname=None, fallback=True, source=False): """given a module name, return the astroid object""" try: filepath = modutils.get_source_file(filepath, include_no_ext=True) source = True except modutils.NoSourceFile: pass if modname is None: try: modname = ".".join(modutils.modpath_from_file(filepath)) except ImportError: modname = filepath if ( modname in self.astroid_cache and self.astroid_cache[modname].file == filepath ): return self.astroid_cache[modname] if source: # pylint: disable=import-outside-toplevel; circular import from astroid.builder import AstroidBuilder return AstroidBuilder(self).file_build(filepath, modname) if fallback and modname: return self.ast_from_module_name(modname) raise exceptions.AstroidBuildingError( "Unable to build an AST for {path}.", path=filepath ) def ast_from_string(self, data, modname="", filepath=None): """ Given some source code as a string, return its corresponding astroid object""" # pylint: disable=import-outside-toplevel; circular import from astroid.builder import AstroidBuilder return AstroidBuilder(self).string_build(data, modname, filepath) def _build_stub_module(self, modname): # pylint: disable=import-outside-toplevel; circular import from astroid.builder import AstroidBuilder return AstroidBuilder(self).string_build("", modname) def _build_namespace_module(self, modname, path): # pylint: disable=import-outside-toplevel; circular import from astroid.builder import build_namespace_package_module return build_namespace_package_module(modname, path) def _can_load_extension(self, modname): if self.always_load_extensions: return True if modutils.is_standard_module(modname): return True parts = modname.split(".") return any( ".".join(parts[:x]) in self.extension_package_whitelist for x in range(1, len(parts) + 1) ) def ast_from_module_name(self, modname, context_file=None): """given a module name, return the astroid object""" if modname in self.astroid_cache: return self.astroid_cache[modname] if modname == "__main__": return self._build_stub_module(modname) if context_file: old_cwd = os.getcwd() os.chdir(os.path.dirname(context_file)) try: found_spec = self.file_from_module_name(modname, context_file) if found_spec.type == spec.ModuleType.PY_ZIPMODULE: module = self.zip_import_data(found_spec.location) if module is not None: return module elif found_spec.type in ( spec.ModuleType.C_BUILTIN, spec.ModuleType.C_EXTENSION, ): if ( found_spec.type == spec.ModuleType.C_EXTENSION and not self._can_load_extension(modname) ): return self._build_stub_module(modname) try: module = modutils.load_module_from_name(modname) except Exception as ex: raise exceptions.AstroidImportError( "Loading {modname} failed with:\n{error}", modname=modname, path=found_spec.location, ) from ex return self.ast_from_module(module, modname) elif found_spec.type == spec.ModuleType.PY_COMPILED: raise exceptions.AstroidImportError( "Unable to load compiled module {modname}.", modname=modname, path=found_spec.location, ) elif found_spec.type == spec.ModuleType.PY_NAMESPACE: return self._build_namespace_module( modname, found_spec.submodule_search_locations ) elif found_spec.type == spec.ModuleType.PY_FROZEN: return self._build_stub_module(modname) if found_spec.location is None: raise exceptions.AstroidImportError( "Can't find a file for module {modname}.", modname=modname ) return self.ast_from_file(found_spec.location, modname, fallback=False) except exceptions.AstroidBuildingError as e: for hook in self._failed_import_hooks: try: return hook(modname) except exceptions.AstroidBuildingError: pass raise e finally: if context_file: os.chdir(old_cwd) def zip_import_data(self, filepath): if zipimport is None: return None # pylint: disable=import-outside-toplevel; circular import from astroid.builder import AstroidBuilder builder = AstroidBuilder(self) for ext in ZIP_IMPORT_EXTS: try: eggpath, resource = filepath.rsplit(ext + os.path.sep, 1) except ValueError: continue try: importer = zipimport.zipimporter(eggpath + ext) zmodname = resource.replace(os.path.sep, ".") if importer.is_package(resource): zmodname = zmodname + ".__init__" module = builder.string_build( importer.get_source(resource), zmodname, filepath ) return module except Exception: # pylint: disable=broad-except continue return None def file_from_module_name(self, modname, contextfile): try: value = self._mod_file_cache[(modname, contextfile)] except KeyError: try: value = modutils.file_info_from_modpath( modname.split("."), context_file=contextfile ) except ImportError as ex: value = exceptions.AstroidImportError( "Failed to import module {modname} with error:\n{error}.", modname=modname, error=ex, ) self._mod_file_cache[(modname, contextfile)] = value if isinstance(value, exceptions.AstroidBuildingError): raise value return value def ast_from_module(self, module, modname=None): """given an imported module, return the astroid object""" modname = modname or module.__name__ if modname in self.astroid_cache: return self.astroid_cache[modname] try: # some builtin modules don't have __file__ attribute filepath = module.__file__ if modutils.is_python_source(filepath): return self.ast_from_file(filepath, modname) except AttributeError: pass # pylint: disable=import-outside-toplevel; circular import from astroid.builder import AstroidBuilder return AstroidBuilder(self).module_build(module, modname) def ast_from_class(self, klass, modname=None): """get astroid for the given class""" if modname is None: try: modname = klass.__module__ except AttributeError as exc: raise exceptions.AstroidBuildingError( "Unable to get module for class {class_name}.", cls=klass, class_repr=safe_repr(klass), modname=modname, ) from exc modastroid = self.ast_from_module_name(modname) return modastroid.getattr(klass.__name__)[0] # XXX def infer_ast_from_something(self, obj, context=None): """infer astroid for the given class""" if hasattr(obj, "__class__") and not isinstance(obj, type): klass = obj.__class__ else: klass = obj try: modname = klass.__module__ except AttributeError as exc: raise exceptions.AstroidBuildingError( "Unable to get module for {class_repr}.", cls=klass, class_repr=safe_repr(klass), ) from exc except Exception as exc: raise exceptions.AstroidImportError( "Unexpected error while retrieving module for {class_repr}:\n" "{error}", cls=klass, class_repr=safe_repr(klass), ) from exc try: name = klass.__name__ except AttributeError as exc: raise exceptions.AstroidBuildingError( "Unable to get name for {class_repr}:\n", cls=klass, class_repr=safe_repr(klass), ) from exc except Exception as exc: raise exceptions.AstroidImportError( "Unexpected error while retrieving name for {class_repr}:\n" "{error}", cls=klass, class_repr=safe_repr(klass), ) from exc # take care, on living object __module__ is regularly wrong :( modastroid = self.ast_from_module_name(modname) if klass is obj: for inferred in modastroid.igetattr(name, context): yield inferred else: for inferred in modastroid.igetattr(name, context): yield inferred.instantiate_class() def register_failed_import_hook(self, hook): """Registers a hook to resolve imports that cannot be found otherwise. `hook` must be a function that accepts a single argument `modname` which contains the name of the module or package that could not be imported. If `hook` can resolve the import, must return a node of type `astroid.Module`, otherwise, it must raise `AstroidBuildingError`. """ self._failed_import_hooks.append(hook) def cache_module(self, module): """Cache a module if no module with the same name is known yet.""" self.astroid_cache.setdefault(module.name, module) def bootstrap(self): """Bootstrap the required AST modules needed for the manager to work The bootstrap usually involves building the AST for the builtins module, which is required by the rest of astroid to work correctly. """ from astroid import raw_building # pylint: disable=import-outside-toplevel raw_building._astroid_bootstrapping() def clear_cache(self): """Clear the underlying cache. Also bootstraps the builtins module.""" self.astroid_cache.clear() self.bootstrap()