diff options
Diffstat (limited to 'Lib/importlib/_bootstrap.py')
| -rw-r--r-- | Lib/importlib/_bootstrap.py | 1343 |
1 files changed, 11 insertions, 1332 deletions
diff --git a/Lib/importlib/_bootstrap.py b/Lib/importlib/_bootstrap.py index c6019ad..cfe6ff9 100644 --- a/Lib/importlib/_bootstrap.py +++ b/Lib/importlib/_bootstrap.py @@ -22,102 +22,6 @@ work. One should use importlib as the public-facing version of this module. # Bootstrap-related code ###################################################### -_CASE_INSENSITIVE_PLATFORMS = 'win', 'cygwin', 'darwin' - - -def _make_relax_case(): - if sys.platform.startswith(_CASE_INSENSITIVE_PLATFORMS): - def _relax_case(): - """True if filenames must be checked case-insensitively.""" - return b'PYTHONCASEOK' in _os.environ - else: - def _relax_case(): - """True if filenames must be checked case-insensitively.""" - return False - return _relax_case - - -def _w_long(x): - """Convert a 32-bit integer to little-endian.""" - return (int(x) & 0xFFFFFFFF).to_bytes(4, 'little') - - -def _r_long(int_bytes): - """Convert 4 bytes in little-endian to an integer.""" - return int.from_bytes(int_bytes, 'little') - - -def _path_join(*path_parts): - """Replacement for os.path.join().""" - return path_sep.join([part.rstrip(path_separators) - for part in path_parts if part]) - - -def _path_split(path): - """Replacement for os.path.split().""" - if len(path_separators) == 1: - front, _, tail = path.rpartition(path_sep) - return front, tail - for x in reversed(path): - if x in path_separators: - front, tail = path.rsplit(x, maxsplit=1) - return front, tail - return '', path - - -def _path_stat(path): - """Stat the path. - - Made a separate function to make it easier to override in experiments - (e.g. cache stat results). - - """ - return _os.stat(path) - - -def _path_is_mode_type(path, mode): - """Test whether the path is the specified mode type.""" - try: - stat_info = _path_stat(path) - except OSError: - return False - return (stat_info.st_mode & 0o170000) == mode - - -def _path_isfile(path): - """Replacement for os.path.isfile.""" - return _path_is_mode_type(path, 0o100000) - - -def _path_isdir(path): - """Replacement for os.path.isdir.""" - if not path: - path = _os.getcwd() - return _path_is_mode_type(path, 0o040000) - - -def _write_atomic(path, data, mode=0o666): - """Best-effort function to write data to a path atomically. - Be prepared to handle a FileExistsError if concurrent writing of the - temporary file is attempted.""" - # id() is used to generate a pseudo-random filename. - path_tmp = '{}.{}'.format(path, id(path)) - fd = _os.open(path_tmp, - _os.O_EXCL | _os.O_CREAT | _os.O_WRONLY, mode & 0o666) - try: - # We first write data to a temporary file, and then use os.replace() to - # perform an atomic rename. - with _io.FileIO(fd, 'wb') as file: - file.write(data) - _os.replace(path_tmp, path) - except OSError: - try: - _os.unlink(path_tmp) - except OSError: - pass - raise - - def _wrap(new, old): """Simple substitute for functools.update_wrapper.""" for replace in ['__module__', '__name__', '__qualname__', '__doc__']: @@ -130,10 +34,6 @@ def _new_module(name): return type(sys)(name) -_code_type = type(_wrap.__code__) - - - class _ManageReload: """Manages the possible clean-up of sys.modules for load_module().""" @@ -309,7 +209,6 @@ def _lock_unlock_module(name): lock.release() # Frame stripping magic ############################################### - def _call_with_frames_removed(f, *args, **kwds): """remove_importlib_frames in import.c will always remove sequences of importlib frames that end with a call to this function @@ -321,230 +220,6 @@ def _call_with_frames_removed(f, *args, **kwds): return f(*args, **kwds) -# Finder/loader utility code ############################################### - -# Magic word to reject .pyc files generated by other Python versions. -# It should change for each incompatible change to the bytecode. -# -# The value of CR and LF is incorporated so if you ever read or write -# a .pyc file in text mode the magic number will be wrong; also, the -# Apple MPW compiler swaps their values, botching string constants. -# -# The magic numbers must be spaced apart at least 2 values, as the -# -U interpeter flag will cause MAGIC+1 being used. They have been -# odd numbers for some time now. -# -# There were a variety of old schemes for setting the magic number. -# The current working scheme is to increment the previous value by -# 10. -# -# Starting with the adoption of PEP 3147 in Python 3.2, every bump in magic -# number also includes a new "magic tag", i.e. a human readable string used -# to represent the magic number in __pycache__ directories. When you change -# the magic number, you must also set a new unique magic tag. Generally this -# can be named after the Python major version of the magic number bump, but -# it can really be anything, as long as it's different than anything else -# that's come before. The tags are included in the following table, starting -# with Python 3.2a0. -# -# Known values: -# Python 1.5: 20121 -# Python 1.5.1: 20121 -# Python 1.5.2: 20121 -# Python 1.6: 50428 -# Python 2.0: 50823 -# Python 2.0.1: 50823 -# Python 2.1: 60202 -# Python 2.1.1: 60202 -# Python 2.1.2: 60202 -# Python 2.2: 60717 -# Python 2.3a0: 62011 -# Python 2.3a0: 62021 -# Python 2.3a0: 62011 (!) -# Python 2.4a0: 62041 -# Python 2.4a3: 62051 -# Python 2.4b1: 62061 -# Python 2.5a0: 62071 -# Python 2.5a0: 62081 (ast-branch) -# Python 2.5a0: 62091 (with) -# Python 2.5a0: 62092 (changed WITH_CLEANUP opcode) -# Python 2.5b3: 62101 (fix wrong code: for x, in ...) -# Python 2.5b3: 62111 (fix wrong code: x += yield) -# Python 2.5c1: 62121 (fix wrong lnotab with for loops and -# storing constants that should have been removed) -# Python 2.5c2: 62131 (fix wrong code: for x, in ... in listcomp/genexp) -# Python 2.6a0: 62151 (peephole optimizations and STORE_MAP opcode) -# Python 2.6a1: 62161 (WITH_CLEANUP optimization) -# Python 2.7a0: 62171 (optimize list comprehensions/change LIST_APPEND) -# Python 2.7a0: 62181 (optimize conditional branches: -# introduce POP_JUMP_IF_FALSE and POP_JUMP_IF_TRUE) -# Python 2.7a0 62191 (introduce SETUP_WITH) -# Python 2.7a0 62201 (introduce BUILD_SET) -# Python 2.7a0 62211 (introduce MAP_ADD and SET_ADD) -# Python 3000: 3000 -# 3010 (removed UNARY_CONVERT) -# 3020 (added BUILD_SET) -# 3030 (added keyword-only parameters) -# 3040 (added signature annotations) -# 3050 (print becomes a function) -# 3060 (PEP 3115 metaclass syntax) -# 3061 (string literals become unicode) -# 3071 (PEP 3109 raise changes) -# 3081 (PEP 3137 make __file__ and __name__ unicode) -# 3091 (kill str8 interning) -# 3101 (merge from 2.6a0, see 62151) -# 3103 (__file__ points to source file) -# Python 3.0a4: 3111 (WITH_CLEANUP optimization). -# Python 3.0a5: 3131 (lexical exception stacking, including POP_EXCEPT) -# Python 3.1a0: 3141 (optimize list, set and dict comprehensions: -# change LIST_APPEND and SET_ADD, add MAP_ADD) -# Python 3.1a0: 3151 (optimize conditional branches: -# introduce POP_JUMP_IF_FALSE and POP_JUMP_IF_TRUE) -# Python 3.2a0: 3160 (add SETUP_WITH) -# tag: cpython-32 -# Python 3.2a1: 3170 (add DUP_TOP_TWO, remove DUP_TOPX and ROT_FOUR) -# tag: cpython-32 -# Python 3.2a2 3180 (add DELETE_DEREF) -# Python 3.3a0 3190 __class__ super closure changed -# Python 3.3a0 3200 (__qualname__ added) -# 3210 (added size modulo 2**32 to the pyc header) -# Python 3.3a1 3220 (changed PEP 380 implementation) -# Python 3.3a4 3230 (revert changes to implicit __class__ closure) -# Python 3.4a1 3250 (evaluate positional default arguments before -# keyword-only defaults) -# Python 3.4a1 3260 (add LOAD_CLASSDEREF; allow locals of class to override -# free vars) -# Python 3.4a1 3270 (various tweaks to the __class__ closure) -# Python 3.4a1 3280 (remove implicit class argument) -# Python 3.4a4 3290 (changes to __qualname__ computation) -# Python 3.4a4 3300 (more changes to __qualname__ computation) -# Python 3.4rc2 3310 (alter __qualname__ computation) -# Python 3.5a0 3320 (matrix multiplication operator) -# -# MAGIC must change whenever the bytecode emitted by the compiler may no -# longer be understood by older implementations of the eval loop (usually -# due to the addition of new opcodes). - -MAGIC_NUMBER = (3320).to_bytes(2, 'little') + b'\r\n' -_RAW_MAGIC_NUMBER = int.from_bytes(MAGIC_NUMBER, 'little') # For import.c - -_PYCACHE = '__pycache__' -_OPT = 'opt-' - -SOURCE_SUFFIXES = ['.py'] # _setup() adds .pyw as needed. - -BYTECODE_SUFFIXES = ['.pyc'] -# Deprecated. -DEBUG_BYTECODE_SUFFIXES = OPTIMIZED_BYTECODE_SUFFIXES = BYTECODE_SUFFIXES - -def cache_from_source(path, debug_override=None, *, optimization=None): - """Given the path to a .py file, return the path to its .pyc file. - - The .py file does not need to exist; this simply returns the path to the - .pyc file calculated as if the .py file were imported. - - The 'optimization' parameter controls the presumed optimization level of - the bytecode file. If 'optimization' is not None, the string representation - of the argument is taken and verified to be alphanumeric (else ValueError - is raised). - - The debug_override parameter is deprecated. If debug_override is not None, - a True value is the same as setting 'optimization' to the empty string - while a False value is equivalent to setting 'optimization' to '1'. - - If sys.implementation.cache_tag is None then NotImplementedError is raised. - - """ - if debug_override is not None: - _warnings.warn('the debug_override parameter is deprecated; use ' - "'optimization' instead", DeprecationWarning) - if optimization is not None: - message = 'debug_override or optimization must be set to None' - raise TypeError(message) - optimization = '' if debug_override else 1 - head, tail = _path_split(path) - base, sep, rest = tail.rpartition('.') - tag = sys.implementation.cache_tag - if tag is None: - raise NotImplementedError('sys.implementation.cache_tag is None') - almost_filename = ''.join([(base if base else rest), sep, tag]) - if optimization is None: - if sys.flags.optimize == 0: - optimization = '' - else: - optimization = sys.flags.optimize - optimization = str(optimization) - if optimization != '': - if not optimization.isalnum(): - raise ValueError('{!r} is not alphanumeric'.format(optimization)) - almost_filename = '{}.{}{}'.format(almost_filename, _OPT, optimization) - return _path_join(head, _PYCACHE, almost_filename + BYTECODE_SUFFIXES[0]) - - -def source_from_cache(path): - """Given the path to a .pyc. file, return the path to its .py file. - - The .pyc file does not need to exist; this simply returns the path to - the .py file calculated to correspond to the .pyc file. If path does - not conform to PEP 3147/488 format, ValueError will be raised. If - sys.implementation.cache_tag is None then NotImplementedError is raised. - - """ - if sys.implementation.cache_tag is None: - raise NotImplementedError('sys.implementation.cache_tag is None') - head, pycache_filename = _path_split(path) - head, pycache = _path_split(head) - if pycache != _PYCACHE: - raise ValueError('{} not bottom-level directory in ' - '{!r}'.format(_PYCACHE, path)) - dot_count = pycache_filename.count('.') - if dot_count not in {2, 3}: - raise ValueError('expected only 2 or 3 dots in ' - '{!r}'.format(pycache_filename)) - elif dot_count == 3: - optimization = pycache_filename.rsplit('.', 2)[-2] - if not optimization.startswith(_OPT): - raise ValueError("optimization portion of filename does not start " - "with {!r}".format(_OPT)) - opt_level = optimization[len(_OPT):] - if not opt_level.isalnum(): - raise ValueError("optimization level {!r} is not an alphanumeric " - "value".format(optimization)) - base_filename = pycache_filename.partition('.')[0] - return _path_join(head, base_filename + SOURCE_SUFFIXES[0]) - - -def _get_sourcefile(bytecode_path): - """Convert a bytecode file path to a source path (if possible). - - This function exists purely for backwards-compatibility for - PyImport_ExecCodeModuleWithFilenames() in the C API. - - """ - if len(bytecode_path) == 0: - return None - rest, _, extension = bytecode_path.rpartition('.') - if not rest or extension.lower()[-3:-1] != 'py': - return bytecode_path - try: - source_path = source_from_cache(bytecode_path) - except (NotImplementedError, ValueError): - source_path = bytecode_path[:-1] - return source_path if _path_isfile(source_path) else bytecode_path - - -def _calc_mode(path): - """Calculate the mode permissions for a bytecode file.""" - try: - mode = _path_stat(path).st_mode - except OSError: - mode = 0o666 - # We always ensure write access so we can update cached files - # later even when the source files are read-only on Windows (#6074) - mode |= 0o200 - return mode - - def _verbose_message(message, *args, verbosity=1): """Print the message to stderr if -v/PYTHONVERBOSE is turned on.""" if sys.flags.verbose >= verbosity: @@ -553,24 +228,6 @@ def _verbose_message(message, *args, verbosity=1): print(message.format(*args), file=sys.stderr) -def _check_name(method): - """Decorator to verify that the module being requested matches the one the - loader can handle. - - The first argument (self) must define _name which the second argument is - compared against. If the comparison fails then ImportError is raised. - - """ - def _check_name_wrapper(self, name=None, *args, **kwargs): - if name is None: - name = self.name - elif self.name != name: - raise ImportError('loader cannot handle %s' % name, name=name) - return method(self, name, *args, **kwargs) - _wrap(_check_name_wrapper, method) - return _check_name_wrapper - - def _requires_builtin(fxn): """Decorator to verify the named module is built-in.""" def _requires_builtin_wrapper(self, fullname): @@ -593,23 +250,6 @@ def _requires_frozen(fxn): return _requires_frozen_wrapper -def _find_module_shim(self, fullname): - """Try to find a loader for the specified module by delegating to - self.find_loader(). - - This method is deprecated in favor of finder.find_spec(). - - """ - # Call find_loader(). If it returns a string (indicating this - # is a namespace package portion), generate a warning and - # return None. - loader, portions = self.find_loader(fullname) - if loader is None and len(portions): - msg = 'Not importing directory {}: missing __init__' - _warnings.warn(msg.format(portions[0]), ImportWarning) - return loader - - # Typically used by loader classes as a method replacement. def _load_module_shim(self, fullname): """Load the specified module into sys.modules and return it. @@ -625,96 +265,6 @@ def _load_module_shim(self, fullname): else: return _load(spec) - -def _validate_bytecode_header(data, source_stats=None, name=None, path=None): - """Validate the header of the passed-in bytecode against source_stats (if - given) and returning the bytecode that can be compiled by compile(). - - All other arguments are used to enhance error reporting. - - ImportError is raised when the magic number is incorrect or the bytecode is - found to be stale. EOFError is raised when the data is found to be - truncated. - - """ - exc_details = {} - if name is not None: - exc_details['name'] = name - else: - # To prevent having to make all messages have a conditional name. - name = '<bytecode>' - if path is not None: - exc_details['path'] = path - magic = data[:4] - raw_timestamp = data[4:8] - raw_size = data[8:12] - if magic != MAGIC_NUMBER: - message = 'bad magic number in {!r}: {!r}'.format(name, magic) - _verbose_message(message) - raise ImportError(message, **exc_details) - elif len(raw_timestamp) != 4: - message = 'reached EOF while reading timestamp in {!r}'.format(name) - _verbose_message(message) - raise EOFError(message) - elif len(raw_size) != 4: - message = 'reached EOF while reading size of source in {!r}'.format(name) - _verbose_message(message) - raise EOFError(message) - if source_stats is not None: - try: - source_mtime = int(source_stats['mtime']) - except KeyError: - pass - else: - if _r_long(raw_timestamp) != source_mtime: - message = 'bytecode is stale for {!r}'.format(name) - _verbose_message(message) - raise ImportError(message, **exc_details) - try: - source_size = source_stats['size'] & 0xFFFFFFFF - except KeyError: - pass - else: - if _r_long(raw_size) != source_size: - raise ImportError('bytecode is stale for {!r}'.format(name), - **exc_details) - return data[12:] - - -def _compile_bytecode(data, name=None, bytecode_path=None, source_path=None): - """Compile bytecode as returned by _validate_bytecode_header().""" - code = marshal.loads(data) - if isinstance(code, _code_type): - _verbose_message('code object from {!r}', bytecode_path) - if source_path is not None: - _imp._fix_co_filename(code, source_path) - return code - else: - raise ImportError('Non-code object in {!r}'.format(bytecode_path), - name=name, path=bytecode_path) - -def _code_to_bytecode(code, mtime=0, source_size=0): - """Compile a code object into bytecode for writing out to a byte-compiled - file.""" - data = bytearray(MAGIC_NUMBER) - data.extend(_w_long(mtime)) - data.extend(_w_long(source_size)) - data.extend(marshal.dumps(code)) - return data - - -def decode_source(source_bytes): - """Decode bytes representing source code and return the string. - - Universal newline support is used in the decoding. - """ - import tokenize # To avoid bootstrap issues. - source_bytes_readline = _io.BytesIO(source_bytes).readline - encoding = tokenize.detect_encoding(source_bytes_readline) - newline_decoder = _io.IncrementalNewlineDecoder(None, True) - return newline_decoder.decode(source_bytes.decode(encoding[0])) - - # Module specifications ####################################################### def _module_repr(module): @@ -855,14 +405,8 @@ class ModuleSpec: def cached(self): if self._cached is None: if self.origin is not None and self._set_fileattr: - filename = self.origin - if filename.endswith(tuple(SOURCE_SUFFIXES)): - try: - self._cached = cache_from_source(filename) - except NotImplementedError: - pass - elif filename.endswith(tuple(BYTECODE_SUFFIXES)): - self._cached = filename + import _frozen_importlib_external as _bootstrap_external # XXX yuck + self._cached = _bootstrap_external._get_cached(self.origin) return self._cached @cached.setter @@ -889,6 +433,7 @@ class ModuleSpec: def spec_from_loader(name, loader, *, origin=None, is_package=None): """Return a module spec based on various loader methods.""" if hasattr(loader, 'get_filename'): + from ._bootstrap_external import spec_from_file_location # XXX yuck if is_package is None: return spec_from_file_location(name, loader=loader) search = [] if is_package else None @@ -911,70 +456,6 @@ def spec_from_loader(name, loader, *, origin=None, is_package=None): _POPULATE = object() -def spec_from_file_location(name, location=None, *, loader=None, - submodule_search_locations=_POPULATE): - """Return a module spec based on a file location. - - To indicate that the module is a package, set - submodule_search_locations to a list of directory paths. An - empty list is sufficient, though its not otherwise useful to the - import system. - - The loader must take a spec as its only __init__() arg. - - """ - if location is None: - # The caller may simply want a partially populated location- - # oriented spec. So we set the location to a bogus value and - # fill in as much as we can. - location = '<unknown>' - if hasattr(loader, 'get_filename'): - # ExecutionLoader - try: - location = loader.get_filename(name) - except ImportError: - pass - - # If the location is on the filesystem, but doesn't actually exist, - # we could return None here, indicating that the location is not - # valid. However, we don't have a good way of testing since an - # indirect location (e.g. a zip file or URL) will look like a - # non-existent file relative to the filesystem. - - spec = ModuleSpec(name, loader, origin=location) - spec._set_fileattr = True - - # Pick a loader if one wasn't provided. - if loader is None: - for loader_class, suffixes in _get_supported_file_loaders(): - if location.endswith(tuple(suffixes)): - loader = loader_class(name, location) - spec.loader = loader - break - else: - return None - - # Set submodule_search_paths appropriately. - if submodule_search_locations is _POPULATE: - # Check the loader. - if hasattr(loader, 'is_package'): - try: - is_package = loader.is_package(name) - except ImportError: - pass - else: - if is_package: - spec.submodule_search_locations = [] - else: - spec.submodule_search_locations = submodule_search_locations - if spec.submodule_search_locations == []: - if location: - dirname = _path_split(location)[0] - spec.submodule_search_locations.append(dirname) - - return spec - - def _spec_from_module(module, loader=None, origin=None): # This function is meant for use in _setup(). try: @@ -1035,6 +516,7 @@ def _init_module_attrs(spec, module, *, override=False): if loader is None: # A backward compatibility hack. if spec.submodule_search_locations is not None: + from ._bootstrap_external import _NamespaceLoader # XXX yuck loader = _NamespaceLoader.__new__(_NamespaceLoader) loader._path = spec.submodule_search_locations try: @@ -1202,29 +684,6 @@ def _load(spec): return _load_unlocked(spec) -def _fix_up_module(ns, name, pathname, cpathname=None): - # This function is used by PyImport_ExecCodeModuleObject(). - loader = ns.get('__loader__') - spec = ns.get('__spec__') - if not loader: - if spec: - loader = spec.loader - elif pathname == cpathname: - loader = SourcelessFileLoader(name, pathname) - else: - loader = SourceFileLoader(name, pathname) - if not spec: - spec = spec_from_file_location(name, pathname, loader=loader) - try: - ns['__spec__'] = spec - ns['__loader__'] = loader - ns['__file__'] = pathname - ns['__cached__'] = cpathname - except Exception: - # Not important enough to report. - pass - - # Loaders ##################################################################### class BuiltinImporter: @@ -1351,6 +810,7 @@ class FrozenImporter: This method is deprecated. Use exec_module() instead. """ + from ._bootstrap_external import _load_module_shim # XXX yuck return _load_module_shim(cls, fullname) @classmethod @@ -1372,742 +832,6 @@ class FrozenImporter: return _imp.is_frozen_package(fullname) -class WindowsRegistryFinder: - - """Meta path finder for modules declared in the Windows registry.""" - - REGISTRY_KEY = ( - 'Software\\Python\\PythonCore\\{sys_version}' - '\\Modules\\{fullname}') - REGISTRY_KEY_DEBUG = ( - 'Software\\Python\\PythonCore\\{sys_version}' - '\\Modules\\{fullname}\\Debug') - DEBUG_BUILD = False # Changed in _setup() - - @classmethod - def _open_registry(cls, key): - try: - return _winreg.OpenKey(_winreg.HKEY_CURRENT_USER, key) - except OSError: - return _winreg.OpenKey(_winreg.HKEY_LOCAL_MACHINE, key) - - @classmethod - def _search_registry(cls, fullname): - if cls.DEBUG_BUILD: - registry_key = cls.REGISTRY_KEY_DEBUG - else: - registry_key = cls.REGISTRY_KEY - key = registry_key.format(fullname=fullname, - sys_version=sys.version[:3]) - try: - with cls._open_registry(key) as hkey: - filepath = _winreg.QueryValue(hkey, '') - except OSError: - return None - return filepath - - @classmethod - def find_spec(cls, fullname, path=None, target=None): - filepath = cls._search_registry(fullname) - if filepath is None: - return None - try: - _path_stat(filepath) - except OSError: - return None - for loader, suffixes in _get_supported_file_loaders(): - if filepath.endswith(tuple(suffixes)): - spec = spec_from_loader(fullname, loader(fullname, filepath), - origin=filepath) - return spec - - @classmethod - def find_module(cls, fullname, path=None): - """Find module named in the registry. - - This method is deprecated. Use exec_module() instead. - - """ - spec = cls.find_spec(fullname, path) - if spec is not None: - return spec.loader - else: - return None - - -class _LoaderBasics: - - """Base class of common code needed by both SourceLoader and - SourcelessFileLoader.""" - - def is_package(self, fullname): - """Concrete implementation of InspectLoader.is_package by checking if - the path returned by get_filename has a filename of '__init__.py'.""" - filename = _path_split(self.get_filename(fullname))[1] - filename_base = filename.rsplit('.', 1)[0] - tail_name = fullname.rpartition('.')[2] - return filename_base == '__init__' and tail_name != '__init__' - - def create_module(self, spec): - """Use default semantics for module creation.""" - - def exec_module(self, module): - """Execute the module.""" - code = self.get_code(module.__name__) - if code is None: - raise ImportError('cannot load module {!r} when get_code() ' - 'returns None'.format(module.__name__)) - _call_with_frames_removed(exec, code, module.__dict__) - - load_module = _load_module_shim - - -class SourceLoader(_LoaderBasics): - - def path_mtime(self, path): - """Optional method that returns the modification time (an int) for the - specified path, where path is a str. - - Raises IOError when the path cannot be handled. - """ - raise IOError - - def path_stats(self, path): - """Optional method returning a metadata dict for the specified path - to by the path (str). - Possible keys: - - 'mtime' (mandatory) is the numeric timestamp of last source - code modification; - - 'size' (optional) is the size in bytes of the source code. - - Implementing this method allows the loader to read bytecode files. - Raises IOError when the path cannot be handled. - """ - return {'mtime': self.path_mtime(path)} - - def _cache_bytecode(self, source_path, cache_path, data): - """Optional method which writes data (bytes) to a file path (a str). - - Implementing this method allows for the writing of bytecode files. - - The source path is needed in order to correctly transfer permissions - """ - # For backwards compatibility, we delegate to set_data() - return self.set_data(cache_path, data) - - def set_data(self, path, data): - """Optional method which writes data (bytes) to a file path (a str). - - Implementing this method allows for the writing of bytecode files. - """ - - - def get_source(self, fullname): - """Concrete implementation of InspectLoader.get_source.""" - path = self.get_filename(fullname) - try: - source_bytes = self.get_data(path) - except OSError as exc: - raise ImportError('source not available through get_data()', - name=fullname) from exc - return decode_source(source_bytes) - - def source_to_code(self, data, path, *, _optimize=-1): - """Return the code object compiled from source. - - The 'data' argument can be any object type that compile() supports. - """ - return _call_with_frames_removed(compile, data, path, 'exec', - dont_inherit=True, optimize=_optimize) - - def get_code(self, fullname): - """Concrete implementation of InspectLoader.get_code. - - Reading of bytecode requires path_stats to be implemented. To write - bytecode, set_data must also be implemented. - - """ - source_path = self.get_filename(fullname) - source_mtime = None - try: - bytecode_path = cache_from_source(source_path) - except NotImplementedError: - bytecode_path = None - else: - try: - st = self.path_stats(source_path) - except IOError: - pass - else: - source_mtime = int(st['mtime']) - try: - data = self.get_data(bytecode_path) - except OSError: - pass - else: - try: - bytes_data = _validate_bytecode_header(data, - source_stats=st, name=fullname, - path=bytecode_path) - except (ImportError, EOFError): - pass - else: - _verbose_message('{} matches {}', bytecode_path, - source_path) - return _compile_bytecode(bytes_data, name=fullname, - bytecode_path=bytecode_path, - source_path=source_path) - source_bytes = self.get_data(source_path) - code_object = self.source_to_code(source_bytes, source_path) - _verbose_message('code object from {}', source_path) - if (not sys.dont_write_bytecode and bytecode_path is not None and - source_mtime is not None): - data = _code_to_bytecode(code_object, source_mtime, - len(source_bytes)) - try: - self._cache_bytecode(source_path, bytecode_path, data) - _verbose_message('wrote {!r}', bytecode_path) - except NotImplementedError: - pass - return code_object - - -class FileLoader: - - """Base file loader class which implements the loader protocol methods that - require file system usage.""" - - def __init__(self, fullname, path): - """Cache the module name and the path to the file found by the - finder.""" - self.name = fullname - self.path = path - - def __eq__(self, other): - return (self.__class__ == other.__class__ and - self.__dict__ == other.__dict__) - - def __hash__(self): - return hash(self.name) ^ hash(self.path) - - @_check_name - def load_module(self, fullname): - """Load a module from a file. - - This method is deprecated. Use exec_module() instead. - - """ - # The only reason for this method is for the name check. - # Issue #14857: Avoid the zero-argument form of super so the implementation - # of that form can be updated without breaking the frozen module - return super(FileLoader, self).load_module(fullname) - - @_check_name - def get_filename(self, fullname): - """Return the path to the source file as found by the finder.""" - return self.path - - def get_data(self, path): - """Return the data from path as raw bytes.""" - with _io.FileIO(path, 'r') as file: - return file.read() - - -class SourceFileLoader(FileLoader, SourceLoader): - - """Concrete implementation of SourceLoader using the file system.""" - - def path_stats(self, path): - """Return the metadata for the path.""" - st = _path_stat(path) - return {'mtime': st.st_mtime, 'size': st.st_size} - - def _cache_bytecode(self, source_path, bytecode_path, data): - # Adapt between the two APIs - mode = _calc_mode(source_path) - return self.set_data(bytecode_path, data, _mode=mode) - - def set_data(self, path, data, *, _mode=0o666): - """Write bytes data to a file.""" - parent, filename = _path_split(path) - path_parts = [] - # Figure out what directories are missing. - while parent and not _path_isdir(parent): - parent, part = _path_split(parent) - path_parts.append(part) - # Create needed directories. - for part in reversed(path_parts): - parent = _path_join(parent, part) - try: - _os.mkdir(parent) - except FileExistsError: - # Probably another Python process already created the dir. - continue - except OSError as exc: - # Could be a permission error, read-only filesystem: just forget - # about writing the data. - _verbose_message('could not create {!r}: {!r}', parent, exc) - return - try: - _write_atomic(path, data, _mode) - _verbose_message('created {!r}', path) - except OSError as exc: - # Same as above: just don't write the bytecode. - _verbose_message('could not create {!r}: {!r}', path, exc) - - -class SourcelessFileLoader(FileLoader, _LoaderBasics): - - """Loader which handles sourceless file imports.""" - - def get_code(self, fullname): - path = self.get_filename(fullname) - data = self.get_data(path) - bytes_data = _validate_bytecode_header(data, name=fullname, path=path) - return _compile_bytecode(bytes_data, name=fullname, bytecode_path=path) - - def get_source(self, fullname): - """Return None as there is no source code.""" - return None - - -# Filled in by _setup(). -EXTENSION_SUFFIXES = [] - - -class ExtensionFileLoader: - - """Loader for extension modules. - - The constructor is designed to work with FileFinder. - - """ - - def __init__(self, name, path): - self.name = name - self.path = path - - def __eq__(self, other): - return (self.__class__ == other.__class__ and - self.__dict__ == other.__dict__) - - def __hash__(self): - return hash(self.name) ^ hash(self.path) - - @_check_name - def load_module(self, fullname): - """Load an extension module.""" - # Once an exec_module() implementation is added we can also - # add a deprecation warning here. - with _ManageReload(fullname): - module = _call_with_frames_removed(_imp.load_dynamic, - fullname, self.path) - _verbose_message('extension module loaded from {!r}', self.path) - is_package = self.is_package(fullname) - if is_package and not hasattr(module, '__path__'): - module.__path__ = [_path_split(self.path)[0]] - module.__loader__ = self - module.__package__ = module.__name__ - if not is_package: - module.__package__ = module.__package__.rpartition('.')[0] - return module - - def is_package(self, fullname): - """Return True if the extension module is a package.""" - file_name = _path_split(self.path)[1] - return any(file_name == '__init__' + suffix - for suffix in EXTENSION_SUFFIXES) - - def get_code(self, fullname): - """Return None as an extension module cannot create a code object.""" - return None - - def get_source(self, fullname): - """Return None as extension modules have no source code.""" - return None - - @_check_name - def get_filename(self, fullname): - """Return the path to the source file as found by the finder.""" - return self.path - - -class _NamespacePath: - """Represents a namespace package's path. It uses the module name - to find its parent module, and from there it looks up the parent's - __path__. When this changes, the module's own path is recomputed, - using path_finder. For top-level modules, the parent module's path - is sys.path.""" - - def __init__(self, name, path, path_finder): - self._name = name - self._path = path - self._last_parent_path = tuple(self._get_parent_path()) - self._path_finder = path_finder - - def _find_parent_path_names(self): - """Returns a tuple of (parent-module-name, parent-path-attr-name)""" - parent, dot, me = self._name.rpartition('.') - if dot == '': - # This is a top-level module. sys.path contains the parent path. - return 'sys', 'path' - # Not a top-level module. parent-module.__path__ contains the - # parent path. - return parent, '__path__' - - def _get_parent_path(self): - parent_module_name, path_attr_name = self._find_parent_path_names() - return getattr(sys.modules[parent_module_name], path_attr_name) - - def _recalculate(self): - # If the parent's path has changed, recalculate _path - parent_path = tuple(self._get_parent_path()) # Make a copy - if parent_path != self._last_parent_path: - spec = self._path_finder(self._name, parent_path) - # Note that no changes are made if a loader is returned, but we - # do remember the new parent path - if spec is not None and spec.loader is None: - if spec.submodule_search_locations: - self._path = spec.submodule_search_locations - self._last_parent_path = parent_path # Save the copy - return self._path - - def __iter__(self): - return iter(self._recalculate()) - - def __len__(self): - return len(self._recalculate()) - - def __repr__(self): - return '_NamespacePath({!r})'.format(self._path) - - def __contains__(self, item): - return item in self._recalculate() - - def append(self, item): - self._path.append(item) - - -# We use this exclusively in module_from_spec() for backward-compatibility. -class _NamespaceLoader: - def __init__(self, name, path, path_finder): - self._path = _NamespacePath(name, path, path_finder) - - @classmethod - def module_repr(cls, module): - """Return repr for the module. - - The method is deprecated. The import machinery does the job itself. - - """ - return '<module {!r} (namespace)>'.format(module.__name__) - - def is_package(self, fullname): - return True - - def get_source(self, fullname): - return '' - - def get_code(self, fullname): - return compile('', '<string>', 'exec', dont_inherit=True) - - def create_module(self, spec): - """Use default semantics for module creation.""" - - def exec_module(self, module): - pass - - def load_module(self, fullname): - """Load a namespace module. - - This method is deprecated. Use exec_module() instead. - - """ - # The import system never calls this method. - _verbose_message('namespace module loaded with path {!r}', self._path) - return _load_module_shim(self, fullname) - - -# Finders ##################################################################### - -class PathFinder: - - """Meta path finder for sys.path and package __path__ attributes.""" - - @classmethod - def invalidate_caches(cls): - """Call the invalidate_caches() method on all path entry finders - stored in sys.path_importer_caches (where implemented).""" - for finder in sys.path_importer_cache.values(): - if hasattr(finder, 'invalidate_caches'): - finder.invalidate_caches() - - @classmethod - def _path_hooks(cls, path): - """Search sequence of hooks for a finder for 'path'. - - If 'hooks' is false then use sys.path_hooks. - - """ - if sys.path_hooks is not None and not sys.path_hooks: - _warnings.warn('sys.path_hooks is empty', ImportWarning) - for hook in sys.path_hooks: - try: - return hook(path) - except ImportError: - continue - else: - return None - - @classmethod - def _path_importer_cache(cls, path): - """Get the finder for the path entry from sys.path_importer_cache. - - If the path entry is not in the cache, find the appropriate finder - and cache it. If no finder is available, store None. - - """ - if path == '': - try: - path = _os.getcwd() - except FileNotFoundError: - # Don't cache the failure as the cwd can easily change to - # a valid directory later on. - return None - try: - finder = sys.path_importer_cache[path] - except KeyError: - finder = cls._path_hooks(path) - sys.path_importer_cache[path] = finder - return finder - - @classmethod - def _legacy_get_spec(cls, fullname, finder): - # This would be a good place for a DeprecationWarning if - # we ended up going that route. - if hasattr(finder, 'find_loader'): - loader, portions = finder.find_loader(fullname) - else: - loader = finder.find_module(fullname) - portions = [] - if loader is not None: - return spec_from_loader(fullname, loader) - spec = ModuleSpec(fullname, None) - spec.submodule_search_locations = portions - return spec - - @classmethod - def _get_spec(cls, fullname, path, target=None): - """Find the loader or namespace_path for this module/package name.""" - # If this ends up being a namespace package, namespace_path is - # the list of paths that will become its __path__ - namespace_path = [] - for entry in path: - if not isinstance(entry, (str, bytes)): - continue - finder = cls._path_importer_cache(entry) - if finder is not None: - if hasattr(finder, 'find_spec'): - spec = finder.find_spec(fullname, target) - else: - spec = cls._legacy_get_spec(fullname, finder) - if spec is None: - continue - if spec.loader is not None: - return spec - portions = spec.submodule_search_locations - if portions is None: - raise ImportError('spec missing loader') - # This is possibly part of a namespace package. - # Remember these path entries (if any) for when we - # create a namespace package, and continue iterating - # on path. - namespace_path.extend(portions) - else: - spec = ModuleSpec(fullname, None) - spec.submodule_search_locations = namespace_path - return spec - - @classmethod - def find_spec(cls, fullname, path=None, target=None): - """find the module on sys.path or 'path' based on sys.path_hooks and - sys.path_importer_cache.""" - if path is None: - path = sys.path - spec = cls._get_spec(fullname, path, target) - if spec is None: - return None - elif spec.loader is None: - namespace_path = spec.submodule_search_locations - if namespace_path: - # We found at least one namespace path. Return a - # spec which can create the namespace package. - spec.origin = 'namespace' - spec.submodule_search_locations = _NamespacePath(fullname, namespace_path, cls._get_spec) - return spec - else: - return None - else: - return spec - - @classmethod - def find_module(cls, fullname, path=None): - """find the module on sys.path or 'path' based on sys.path_hooks and - sys.path_importer_cache. - - This method is deprecated. Use find_spec() instead. - - """ - spec = cls.find_spec(fullname, path) - if spec is None: - return None - return spec.loader - - -class FileFinder: - - """File-based finder. - - Interactions with the file system are cached for performance, being - refreshed when the directory the finder is handling has been modified. - - """ - - def __init__(self, path, *loader_details): - """Initialize with the path to search on and a variable number of - 2-tuples containing the loader and the file suffixes the loader - recognizes.""" - loaders = [] - for loader, suffixes in loader_details: - loaders.extend((suffix, loader) for suffix in suffixes) - self._loaders = loaders - # Base (directory) path - self.path = path or '.' - self._path_mtime = -1 - self._path_cache = set() - self._relaxed_path_cache = set() - - def invalidate_caches(self): - """Invalidate the directory mtime.""" - self._path_mtime = -1 - - find_module = _find_module_shim - - def find_loader(self, fullname): - """Try to find a loader for the specified module, or the namespace - package portions. Returns (loader, list-of-portions). - - This method is deprecated. Use find_spec() instead. - - """ - spec = self.find_spec(fullname) - if spec is None: - return None, [] - return spec.loader, spec.submodule_search_locations or [] - - def _get_spec(self, loader_class, fullname, path, smsl, target): - loader = loader_class(fullname, path) - return spec_from_file_location(fullname, path, loader=loader, - submodule_search_locations=smsl) - - def find_spec(self, fullname, target=None): - """Try to find a loader for the specified module, or the namespace - package portions. Returns (loader, list-of-portions).""" - is_namespace = False - tail_module = fullname.rpartition('.')[2] - try: - mtime = _path_stat(self.path or _os.getcwd()).st_mtime - except OSError: - mtime = -1 - if mtime != self._path_mtime: - self._fill_cache() - self._path_mtime = mtime - # tail_module keeps the original casing, for __file__ and friends - if _relax_case(): - cache = self._relaxed_path_cache - cache_module = tail_module.lower() - else: - cache = self._path_cache - cache_module = tail_module - # Check if the module is the name of a directory (and thus a package). - if cache_module in cache: - base_path = _path_join(self.path, tail_module) - for suffix, loader_class in self._loaders: - init_filename = '__init__' + suffix - full_path = _path_join(base_path, init_filename) - if _path_isfile(full_path): - return self._get_spec(loader_class, fullname, full_path, [base_path], target) - else: - # If a namespace package, return the path if we don't - # find a module in the next section. - is_namespace = _path_isdir(base_path) - # Check for a file w/ a proper suffix exists. - for suffix, loader_class in self._loaders: - full_path = _path_join(self.path, tail_module + suffix) - _verbose_message('trying {}'.format(full_path), verbosity=2) - if cache_module + suffix in cache: - if _path_isfile(full_path): - return self._get_spec(loader_class, fullname, full_path, None, target) - if is_namespace: - _verbose_message('possible namespace for {}'.format(base_path)) - spec = ModuleSpec(fullname, None) - spec.submodule_search_locations = [base_path] - return spec - return None - - def _fill_cache(self): - """Fill the cache of potential modules and packages for this directory.""" - path = self.path - try: - contents = _os.listdir(path or _os.getcwd()) - except (FileNotFoundError, PermissionError, NotADirectoryError): - # Directory has either been removed, turned into a file, or made - # unreadable. - contents = [] - # We store two cached versions, to handle runtime changes of the - # PYTHONCASEOK environment variable. - if not sys.platform.startswith('win'): - self._path_cache = set(contents) - else: - # Windows users can import modules with case-insensitive file - # suffixes (for legacy reasons). Make the suffix lowercase here - # so it's done once instead of for every import. This is safe as - # the specified suffixes to check against are always specified in a - # case-sensitive manner. - lower_suffix_contents = set() - for item in contents: - name, dot, suffix = item.partition('.') - if dot: - new_name = '{}.{}'.format(name, suffix.lower()) - else: - new_name = name - lower_suffix_contents.add(new_name) - self._path_cache = lower_suffix_contents - if sys.platform.startswith(_CASE_INSENSITIVE_PLATFORMS): - self._relaxed_path_cache = {fn.lower() for fn in contents} - - @classmethod - def path_hook(cls, *loader_details): - """A class method which returns a closure to use on sys.path_hook - which will return an instance using the specified loaders and the path - called on the closure. - - If the path called on the closure is not a directory, ImportError is - raised. - - """ - def path_hook_for_FileFinder(path): - """Path hook for importlib.machinery.FileFinder.""" - if not _path_isdir(path): - raise ImportError('only directories are supported', path=path) - return cls(path, *loader_details) - - return path_hook_for_FileFinder - - def __repr__(self): - return 'FileFinder({!r})'.format(self.path) - - # Import itself ############################################################### class _ImportLockContext: @@ -2305,17 +1029,6 @@ def _calc___package__(globals): return package -def _get_supported_file_loaders(): - """Returns a list of file-based module loaders. - - Each item is a tuple (loader, suffixes). - """ - extensions = ExtensionFileLoader, _imp.extension_suffixes() - source = SourceFileLoader, SOURCE_SUFFIXES - bytecode = SourcelessFileLoader, BYTECODE_SUFFIXES - return [extensions, source, bytecode] - - def __import__(name, globals=None, locals=None, fromlist=(), level=0): """Import a module. @@ -2385,34 +1098,13 @@ def _setup(sys_module, _imp_module): # Directly load built-in modules needed during bootstrap. self_module = sys.modules[__name__] - for builtin_name in ('_io', '_warnings', 'builtins', 'marshal'): + for builtin_name in ('_warnings',): if builtin_name not in sys.modules: builtin_module = _builtin_from_name(builtin_name) else: builtin_module = sys.modules[builtin_name] setattr(self_module, builtin_name, builtin_module) - # Directly load the os module (needed during bootstrap). - os_details = ('posix', ['/']), ('nt', ['\\', '/']) - for builtin_os, path_separators in os_details: - # Assumption made in _path_join() - assert all(len(sep) == 1 for sep in path_separators) - path_sep = path_separators[0] - if builtin_os in sys.modules: - os_module = sys.modules[builtin_os] - break - else: - try: - os_module = _builtin_from_name(builtin_os) - break - except ImportError: - continue - else: - raise ImportError('importlib requires posix or nt') - setattr(self_module, '_os', os_module) - setattr(self_module, 'path_sep', path_sep) - setattr(self_module, 'path_separators', ''.join(path_separators)) - # Directly load the _thread module (needed during bootstrap). try: thread_module = _builtin_from_name('_thread') @@ -2425,27 +1117,14 @@ def _setup(sys_module, _imp_module): weakref_module = _builtin_from_name('_weakref') setattr(self_module, '_weakref', weakref_module) - # Directly load the winreg module (needed during bootstrap). - if builtin_os == 'nt': - winreg_module = _builtin_from_name('winreg') - setattr(self_module, '_winreg', winreg_module) - - # Constants - setattr(self_module, '_relax_case', _make_relax_case()) - EXTENSION_SUFFIXES.extend(_imp.extension_suffixes()) - if builtin_os == 'nt': - SOURCE_SUFFIXES.append('.pyw') - if '_d.pyd' in EXTENSION_SUFFIXES: - WindowsRegistryFinder.DEBUG_BUILD = True - def _install(sys_module, _imp_module): """Install importlib as the implementation of import.""" _setup(sys_module, _imp_module) - supported_loaders = _get_supported_file_loaders() - sys.path_hooks.extend([FileFinder.path_hook(*supported_loaders)]) + sys.meta_path.append(BuiltinImporter) sys.meta_path.append(FrozenImporter) - if _os.__name__ == 'nt': - sys.meta_path.append(WindowsRegistryFinder) - sys.meta_path.append(PathFinder) + + import _frozen_importlib_external + _frozen_importlib_external._install(sys.modules[__name__]) + sys.modules[__name__]._bootstrap_external = _frozen_importlib_external |