| """Core implementation of import. |
| |
| This module is NOT meant to be directly imported! It has been designed such |
| that it can be bootstrapped into Python as the implementation of import. As |
| such it requires the injection of specific modules and attributes in order to |
| work. One should use importlib as the public-facing version of this module. |
| |
| """ |
| # |
| # IMPORTANT: Whenever making changes to this module, be sure to run |
| # a top-level make in order to get the frozen version of the module |
| # update. Not doing so will result in the Makefile to fail for |
| # all others who don't have a ./python around to freeze the module |
| # in the early stages of compilation. |
| # |
| |
| # See importlib._setup() for what is injected into the global namespace. |
| |
| # When editing this code be aware that code executed at import time CANNOT |
| # reference any injected objects! This includes not only global code but also |
| # anything specified at the class level. |
| |
| # 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__']: |
| if hasattr(old, replace): |
| setattr(new, replace, getattr(old, replace)) |
| new.__dict__.update(old.__dict__) |
| |
| |
| 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().""" |
| |
| def __init__(self, name): |
| self._name = name |
| |
| def __enter__(self): |
| self._is_reload = self._name in sys.modules |
| |
| def __exit__(self, *args): |
| if any(arg is not None for arg in args) and not self._is_reload: |
| try: |
| del sys.modules[self._name] |
| except KeyError: |
| pass |
| |
| # Module-level locking ######################################################## |
| |
| # A dict mapping module names to weakrefs of _ModuleLock instances |
| _module_locks = {} |
| # A dict mapping thread ids to _ModuleLock instances |
| _blocking_on = {} |
| |
| |
| class _DeadlockError(RuntimeError): |
| pass |
| |
| |
| class _ModuleLock: |
| """A recursive lock implementation which is able to detect deadlocks |
| (e.g. thread 1 trying to take locks A then B, and thread 2 trying to |
| take locks B then A). |
| """ |
| |
| def __init__(self, name): |
| self.lock = _thread.allocate_lock() |
| self.wakeup = _thread.allocate_lock() |
| self.name = name |
| self.owner = None |
| self.count = 0 |
| self.waiters = 0 |
| |
| def has_deadlock(self): |
| # Deadlock avoidance for concurrent circular imports. |
| me = _thread.get_ident() |
| tid = self.owner |
| while True: |
| lock = _blocking_on.get(tid) |
| if lock is None: |
| return False |
| tid = lock.owner |
| if tid == me: |
| return True |
| |
| def acquire(self): |
| """ |
| Acquire the module lock. If a potential deadlock is detected, |
| a _DeadlockError is raised. |
| Otherwise, the lock is always acquired and True is returned. |
| """ |
| tid = _thread.get_ident() |
| _blocking_on[tid] = self |
| try: |
| while True: |
| with self.lock: |
| if self.count == 0 or self.owner == tid: |
| self.owner = tid |
| self.count += 1 |
| return True |
| if self.has_deadlock(): |
| raise _DeadlockError('deadlock detected by %r' % self) |
| if self.wakeup.acquire(False): |
| self.waiters += 1 |
| # Wait for a release() call |
| self.wakeup.acquire() |
| self.wakeup.release() |
| finally: |
| del _blocking_on[tid] |
| |
| def release(self): |
| tid = _thread.get_ident() |
| with self.lock: |
| if self.owner != tid: |
| raise RuntimeError('cannot release un-acquired lock') |
| assert self.count > 0 |
| self.count -= 1 |
| if self.count == 0: |
| self.owner = None |
| if self.waiters: |
| self.waiters -= 1 |
| self.wakeup.release() |
| |
| def __repr__(self): |
| return '_ModuleLock({!r}) at {}'.format(self.name, id(self)) |
| |
| |
| class _DummyModuleLock: |
| """A simple _ModuleLock equivalent for Python builds without |
| multi-threading support.""" |
| |
| def __init__(self, name): |
| self.name = name |
| self.count = 0 |
| |
| def acquire(self): |
| self.count += 1 |
| return True |
| |
| def release(self): |
| if self.count == 0: |
| raise RuntimeError('cannot release un-acquired lock') |
| self.count -= 1 |
| |
| def __repr__(self): |
| return '_DummyModuleLock({!r}) at {}'.format(self.name, id(self)) |
| |
| |
| class _ModuleLockManager: |
| |
| def __init__(self, name): |
| self._name = name |
| self._lock = None |
| |
| def __enter__(self): |
| try: |
| self._lock = _get_module_lock(self._name) |
| finally: |
| _imp.release_lock() |
| self._lock.acquire() |
| |
| def __exit__(self, *args, **kwargs): |
| self._lock.release() |
| |
| |
| # The following two functions are for consumption by Python/import.c. |
| |
| def _get_module_lock(name): |
| """Get or create the module lock for a given module name. |
| |
| Should only be called with the import lock taken.""" |
| lock = None |
| try: |
| lock = _module_locks[name]() |
| except KeyError: |
| pass |
| if lock is None: |
| if _thread is None: |
| lock = _DummyModuleLock(name) |
| else: |
| lock = _ModuleLock(name) |
| def cb(_): |
| del _module_locks[name] |
| _module_locks[name] = _weakref.ref(lock, cb) |
| return lock |
| |
| def _lock_unlock_module(name): |
| """Release the global import lock, and acquires then release the |
| module lock for a given module name. |
| This is used to ensure a module is completely initialized, in the |
| event it is being imported by another thread. |
| |
| Should only be called with the import lock taken.""" |
| lock = _get_module_lock(name) |
| _imp.release_lock() |
| try: |
| lock.acquire() |
| except _DeadlockError: |
| # Concurrent circular import, we'll accept a partially initialized |
| # module object. |
| pass |
| else: |
| 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 |
| |
| Use it instead of a normal call in places where including the importlib |
| frames introduces unwanted noise into the traceback (e.g. when executing |
| module code) |
| """ |
| 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) |
| # |
| # 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 = (3310).to_bytes(2, 'little') + b'\r\n' |
| _RAW_MAGIC_NUMBER = int.from_bytes(MAGIC_NUMBER, 'little') # For import.c |
| |
| _PYCACHE = '__pycache__' |
| |
| SOURCE_SUFFIXES = ['.py'] # _setup() adds .pyw as needed. |
| |
| DEBUG_BYTECODE_SUFFIXES = ['.pyc'] |
| OPTIMIZED_BYTECODE_SUFFIXES = ['.pyo'] |
| |
| def cache_from_source(path, debug_override=None): |
| """Given the path to a .py file, return the path to its .pyc/.pyo file. |
| |
| The .py file does not need to exist; this simply returns the path to the |
| .pyc/.pyo file calculated as if the .py file were imported. The extension |
| will be .pyc unless sys.flags.optimize is non-zero, then it will be .pyo. |
| |
| If debug_override is not None, then it must be a boolean and is used in |
| place of sys.flags.optimize. |
| |
| If sys.implementation.cache_tag is None then NotImplementedError is raised. |
| |
| """ |
| debug = not sys.flags.optimize if debug_override is None else debug_override |
| if debug: |
| suffixes = DEBUG_BYTECODE_SUFFIXES |
| else: |
| suffixes = OPTIMIZED_BYTECODE_SUFFIXES |
| 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') |
| filename = ''.join([(base if base else rest), sep, tag, suffixes[0]]) |
| return _path_join(head, _PYCACHE, filename) |
| |
| |
| def source_from_cache(path): |
| """Given the path to a .pyc./.pyo file, return the path to its .py file. |
| |
| The .pyc/.pyo file does not need to exist; this simply returns the path to |
| the .py file calculated to correspond to the .pyc/.pyo file. If path does |
| not conform to PEP 3147 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)) |
| if pycache_filename.count('.') != 2: |
| raise ValueError('expected only 2 dots in ' |
| '{!r}'.format(pycache_filename)) |
| 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: |
| if not message.startswith(('#', 'import ')): |
| message = '# ' + message |
| 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): |
| if fullname not in sys.builtin_module_names: |
| raise ImportError('{!r} is not a built-in module'.format(fullname), |
| name=fullname) |
| return fxn(self, fullname) |
| _wrap(_requires_builtin_wrapper, fxn) |
| return _requires_builtin_wrapper |
| |
| |
| def _requires_frozen(fxn): |
| """Decorator to verify the named module is frozen.""" |
| def _requires_frozen_wrapper(self, fullname): |
| if not _imp.is_frozen(fullname): |
| raise ImportError('{!r} is not a frozen module'.format(fullname), |
| name=fullname) |
| return fxn(self, fullname) |
| _wrap(_requires_frozen_wrapper, 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 |
| |
| |
| def _load_module_shim(self, fullname): |
| """Load the specified module into sys.modules and return it. |
| |
| This method is deprecated. Use loader.exec_module instead. |
| |
| """ |
| spec = spec_from_loader(fullname, self) |
| methods = _SpecMethods(spec) |
| if fullname in sys.modules: |
| module = sys.modules[fullname] |
| methods.exec(module) |
| return sys.modules[fullname] |
| else: |
| return methods.load() |
| |
| |
| 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): |
| # The implementation of ModuleType__repr__(). |
| loader = getattr(module, '__loader__', None) |
| if hasattr(loader, 'module_repr'): |
| # As soon as BuiltinImporter, FrozenImporter, and NamespaceLoader |
| # drop their implementations for module_repr. we can add a |
| # deprecation warning here. |
| try: |
| return loader.module_repr(module) |
| except Exception: |
| pass |
| try: |
| spec = module.__spec__ |
| except AttributeError: |
| pass |
| else: |
| if spec is not None: |
| return _SpecMethods(spec).module_repr() |
| |
| # We could use module.__class__.__name__ instead of 'module' in the |
| # various repr permutations. |
| try: |
| name = module.__name__ |
| except AttributeError: |
| name = '?' |
| try: |
| filename = module.__file__ |
| except AttributeError: |
| if loader is None: |
| return '<module {!r}>'.format(name) |
| else: |
| return '<module {!r} ({!r})>'.format(name, loader) |
| else: |
| return '<module {!r} from {!r}>'.format(name, filename) |
| |
| |
| class _installed_safely: |
| |
| def __init__(self, module): |
| self._module = module |
| self._spec = module.__spec__ |
| |
| def __enter__(self): |
| # This must be done before putting the module in sys.modules |
| # (otherwise an optimization shortcut in import.c becomes |
| # wrong) |
| self._spec._initializing = True |
| sys.modules[self._spec.name] = self._module |
| |
| def __exit__(self, *args): |
| try: |
| spec = self._spec |
| if any(arg is not None for arg in args): |
| try: |
| del sys.modules[spec.name] |
| except KeyError: |
| pass |
| else: |
| _verbose_message('import {!r} # {!r}', spec.name, spec.loader) |
| finally: |
| self._spec._initializing = False |
| |
| |
| class ModuleSpec: |
| """The specification for a module, used for loading. |
| |
| A module's spec is the source for information about the module. For |
| data associated with the module, including source, use the spec's |
| loader. |
| |
| `name` is the absolute name of the module. `loader` is the loader |
| to use when loading the module. `parent` is the name of the |
| package the module is in. The parent is derived from the name. |
| |
| `is_package` determines if the module is considered a package or |
| not. On modules this is reflected by the `__path__` attribute. |
| |
| `origin` is the specific location used by the loader from which to |
| load the module, if that information is available. When filename is |
| set, origin will match. |
| |
| `has_location` indicates that a spec's "origin" reflects a location. |
| When this is True, `__file__` attribute of the module is set. |
| |
| `cached` is the location of the cached bytecode file, if any. It |
| corresponds to the `__cached__` attribute. |
| |
| `submodule_search_locations` is the sequence of path entries to |
| search when importing submodules. If set, is_package should be |
| True--and False otherwise. |
| |
| Packages are simply modules that (may) have submodules. If a spec |
| has a non-None value in `submodule_search_locations`, the import |
| system will consider modules loaded from the spec as packages. |
| |
| Only finders (see importlib.abc.MetaPathFinder and |
| importlib.abc.PathEntryFinder) should modify ModuleSpec instances. |
| |
| """ |
| |
| def __init__(self, name, loader, *, origin=None, loader_state=None, |
| is_package=None): |
| self.name = name |
| self.loader = loader |
| self.origin = origin |
| self.loader_state = loader_state |
| self.submodule_search_locations = [] if is_package else None |
| |
| # file-location attributes |
| self._set_fileattr = False |
| self._cached = None |
| |
| def __repr__(self): |
| args = ['name={!r}'.format(self.name), |
| 'loader={!r}'.format(self.loader)] |
| if self.origin is not None: |
| args.append('origin={!r}'.format(self.origin)) |
| if self.submodule_search_locations is not None: |
| args.append('submodule_search_locations={}' |
| .format(self.submodule_search_locations)) |
| return '{}({})'.format(self.__class__.__name__, ', '.join(args)) |
| |
| def __eq__(self, other): |
| smsl = self.submodule_search_locations |
| try: |
| return (self.name == other.name and |
| self.loader == other.loader and |
| self.origin == other.origin and |
| smsl == other.submodule_search_locations and |
| self.cached == other.cached and |
| self.has_location == other.has_location) |
| except AttributeError: |
| return False |
| |
| @property |
| 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 |
| return self._cached |
| |
| @cached.setter |
| def cached(self, cached): |
| self._cached = cached |
| |
| @property |
| def parent(self): |
| """The name of the module's parent.""" |
| if self.submodule_search_locations is None: |
| return self.name.rpartition('.')[0] |
| else: |
| return self.name |
| |
| @property |
| def has_location(self): |
| return self._set_fileattr |
| |
| @has_location.setter |
| def has_location(self, value): |
| self._set_fileattr = bool(value) |
| |
| |
| 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'): |
| if is_package is None: |
| return spec_from_file_location(name, loader=loader) |
| search = [] if is_package else None |
| return spec_from_file_location(name, loader=loader, |
| submodule_search_locations=search) |
| |
| if is_package is None: |
| if hasattr(loader, 'is_package'): |
| try: |
| is_package = loader.is_package(name) |
| except ImportError: |
| is_package = None # aka, undefined |
| else: |
| # the default |
| is_package = False |
| |
| return ModuleSpec(name, loader, origin=origin, is_package=is_package) |
| |
| |
| _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: |
| spec = module.__spec__ |
| except AttributeError: |
| pass |
| else: |
| if spec is not None: |
| return spec |
| |
| name = module.__name__ |
| if loader is None: |
| try: |
| loader = module.__loader__ |
| except AttributeError: |
| # loader will stay None. |
| pass |
| try: |
| location = module.__file__ |
| except AttributeError: |
| location = None |
| if origin is None: |
| if location is None: |
| try: |
| origin = loader._ORIGIN |
| except AttributeError: |
| origin = None |
| else: |
| origin = location |
| try: |
| cached = module.__cached__ |
| except AttributeError: |
| cached = None |
| try: |
| submodule_search_locations = list(module.__path__) |
| except AttributeError: |
| submodule_search_locations = None |
| |
| spec = ModuleSpec(name, loader, origin=origin) |
| spec._set_fileattr = False if location is None else True |
| spec.cached = cached |
| spec.submodule_search_locations = submodule_search_locations |
| return spec |
| |
| |
| class _SpecMethods: |
| |
| """Convenience wrapper around spec objects to provide spec-specific |
| methods.""" |
| |
| # The various spec_from_* functions could be made factory methods here. |
| |
| def __init__(self, spec): |
| self.spec = spec |
| |
| def module_repr(self): |
| """Return the repr to use for the module.""" |
| # We mostly replicate _module_repr() using the spec attributes. |
| spec = self.spec |
| name = '?' if spec.name is None else spec.name |
| if spec.origin is None: |
| if spec.loader is None: |
| return '<module {!r}>'.format(name) |
| else: |
| return '<module {!r} ({!r})>'.format(name, spec.loader) |
| else: |
| if spec.has_location: |
| return '<module {!r} from {!r}>'.format(name, spec.origin) |
| else: |
| return '<module {!r} ({})>'.format(spec.name, spec.origin) |
| |
| def init_module_attrs(self, module, *, _override=False, _force_name=True): |
| """Set the module's attributes. |
| |
| All missing import-related module attributes will be set. Here |
| is how the spec attributes map onto the module: |
| |
| spec.name -> module.__name__ |
| spec.loader -> module.__loader__ |
| spec.parent -> module.__package__ |
| spec -> module.__spec__ |
| |
| Optional: |
| spec.origin -> module.__file__ (if spec.set_fileattr is true) |
| spec.cached -> module.__cached__ (if __file__ also set) |
| spec.submodule_search_locations -> module.__path__ (if set) |
| |
| """ |
| spec = self.spec |
| |
| # The passed in module may be not support attribute assignment, |
| # in which case we simply don't set the attributes. |
| |
| # __name__ |
| if (_override or _force_name or |
| getattr(module, '__name__', None) is None): |
| try: |
| module.__name__ = spec.name |
| except AttributeError: |
| pass |
| |
| # __loader__ |
| if _override or getattr(module, '__loader__', None) is None: |
| loader = spec.loader |
| if loader is None: |
| # A backward compatibility hack. |
| if spec.submodule_search_locations is not None: |
| loader = _NamespaceLoader.__new__(_NamespaceLoader) |
| loader._path = spec.submodule_search_locations |
| try: |
| module.__loader__ = loader |
| except AttributeError: |
| pass |
| |
| # __package__ |
| if _override or getattr(module, '__package__', None) is None: |
| try: |
| module.__package__ = spec.parent |
| except AttributeError: |
| pass |
| |
| # __spec__ |
| try: |
| module.__spec__ = spec |
| except AttributeError: |
| pass |
| |
| # __path__ |
| if _override or getattr(module, '__path__', None) is None: |
| if spec.submodule_search_locations is not None: |
| try: |
| module.__path__ = spec.submodule_search_locations |
| except AttributeError: |
| pass |
| |
| if spec.has_location: |
| # __file__ |
| if _override or getattr(module, '__file__', None) is None: |
| try: |
| module.__file__ = spec.origin |
| except AttributeError: |
| pass |
| |
| # __cached__ |
| if _override or getattr(module, '__cached__', None) is None: |
| if spec.cached is not None: |
| try: |
| module.__cached__ = spec.cached |
| except AttributeError: |
| pass |
| |
| def create(self): |
| """Return a new module to be loaded. |
| |
| The import-related module attributes are also set with the |
| appropriate values from the spec. |
| |
| """ |
| spec = self.spec |
| # Typically loaders will not implement create_module(). |
| if hasattr(spec.loader, 'create_module'): |
| # If create_module() returns `None` it means the default |
| # module creation should be used. |
| module = spec.loader.create_module(spec) |
| else: |
| module = None |
| if module is None: |
| # This must be done before open() is ever called as the 'io' |
| # module implicitly imports 'locale' and would otherwise |
| # trigger an infinite loop. |
| module = _new_module(spec.name) |
| self.init_module_attrs(module) |
| return module |
| |
| def _exec(self, module): |
| """Do everything necessary to execute the module. |
| |
| The namespace of `module` is used as the target of execution. |
| This method uses the loader's `exec_module()` method. |
| |
| """ |
| self.spec.loader.exec_module(module) |
| |
| # Used by importlib.reload() and _load_module_shim(). |
| def exec(self, module): |
| """Execute the spec in an existing module's namespace.""" |
| name = self.spec.name |
| _imp.acquire_lock() |
| with _ModuleLockManager(name): |
| if sys.modules.get(name) is not module: |
| msg = 'module {!r} not in sys.modules'.format(name) |
| raise ImportError(msg, name=name) |
| if self.spec.loader is None: |
| if self.spec.submodule_search_locations is None: |
| raise ImportError('missing loader', name=self.spec.name) |
| # namespace package |
| self.init_module_attrs(module, _override=True) |
| return module |
| self.init_module_attrs(module, _override=True) |
| if not hasattr(self.spec.loader, 'exec_module'): |
| # (issue19713) Once BuiltinImporter and ExtensionFileLoader |
| # have exec_module() implemented, we can add a deprecation |
| # warning here. |
| self.spec.loader.load_module(name) |
| else: |
| self._exec(module) |
| return sys.modules[name] |
| |
| def _load_backward_compatible(self): |
| # (issue19713) Once BuiltinImporter and ExtensionFileLoader |
| # have exec_module() implemented, we can add a deprecation |
| # warning here. |
| spec = self.spec |
| spec.loader.load_module(spec.name) |
| # The module must be in sys.modules at this point! |
| module = sys.modules[spec.name] |
| if getattr(module, '__loader__', None) is None: |
| try: |
| module.__loader__ = spec.loader |
| except AttributeError: |
| pass |
| if getattr(module, '__package__', None) is None: |
| try: |
| # Since module.__path__ may not line up with |
| # spec.submodule_search_paths, we can't necessarily rely |
| # on spec.parent here. |
| module.__package__ = module.__name__ |
| if not hasattr(module, '__path__'): |
| module.__package__ = spec.name.rpartition('.')[0] |
| except AttributeError: |
| pass |
| if getattr(module, '__spec__', None) is None: |
| try: |
| module.__spec__ = spec |
| except AttributeError: |
| pass |
| return module |
| |
| def _load_unlocked(self): |
| # A helper for direct use by the import system. |
| if self.spec.loader is not None: |
| # not a namespace package |
| if not hasattr(self.spec.loader, 'exec_module'): |
| return self._load_backward_compatible() |
| |
| module = self.create() |
| with _installed_safely(module): |
| if self.spec.loader is None: |
| if self.spec.submodule_search_locations is None: |
| raise ImportError('missing loader', name=self.spec.name) |
| # A namespace package so do nothing. |
| else: |
| self._exec(module) |
| |
| # We don't ensure that the import-related module attributes get |
| # set in the sys.modules replacement case. Such modules are on |
| # their own. |
| return sys.modules[self.spec.name] |
| |
| # A method used during testing of _load_unlocked() and by |
| # _load_module_shim(). |
| def load(self): |
| """Return a new module object, loaded by the spec's loader. |
| |
| The module is not added to its parent. |
| |
| If a module is already in sys.modules, that existing module gets |
| clobbered. |
| |
| """ |
| _imp.acquire_lock() |
| with _ModuleLockManager(self.spec.name): |
| return self._load_unlocked() |
| |
| |
| 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: |
| |
| """Meta path import for built-in modules. |
| |
| All methods are either class or static methods to avoid the need to |
| instantiate the class. |
| |
| """ |
| |
| @staticmethod |
| def module_repr(module): |
| """Return repr for the module. |
| |
| The method is deprecated. The import machinery does the job itself. |
| |
| """ |
| return '<module {!r} (built-in)>'.format(module.__name__) |
| |
| @classmethod |
| def find_spec(cls, fullname, path=None, target=None): |
| if path is not None: |
| return None |
| if _imp.is_builtin(fullname): |
| return spec_from_loader(fullname, cls, origin='built-in') |
| else: |
| return None |
| |
| @classmethod |
| def find_module(cls, fullname, path=None): |
| """Find the built-in module. |
| |
| If 'path' is ever specified then the search is considered a failure. |
| |
| This method is deprecated. Use find_spec() instead. |
| |
| """ |
| spec = cls.find_spec(fullname, path) |
| return spec.loader if spec is not None else None |
| |
| @classmethod |
| @_requires_builtin |
| def load_module(cls, fullname): |
| """Load a built-in 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.init_builtin, fullname) |
| module.__loader__ = cls |
| module.__package__ = '' |
| return module |
| |
| @classmethod |
| @_requires_builtin |
| def get_code(cls, fullname): |
| """Return None as built-in modules do not have code objects.""" |
| return None |
| |
| @classmethod |
| @_requires_builtin |
| def get_source(cls, fullname): |
| """Return None as built-in modules do not have source code.""" |
| return None |
| |
| @classmethod |
| @_requires_builtin |
| def is_package(cls, fullname): |
| """Return False as built-in modules are never packages.""" |
| return False |
| |
| |
| class FrozenImporter: |
| |
| """Meta path import for frozen modules. |
| |
| All methods are either class or static methods to avoid the need to |
| instantiate the class. |
| |
| """ |
| |
| @staticmethod |
| def module_repr(m): |
| """Return repr for the module. |
| |
| The method is deprecated. The import machinery does the job itself. |
| |
| """ |
| return '<module {!r} (frozen)>'.format(m.__name__) |
| |
| @classmethod |
| def find_spec(cls, fullname, path=None, target=None): |
| if _imp.is_frozen(fullname): |
| return spec_from_loader(fullname, cls, origin='frozen') |
| else: |
| return None |
| |
| @classmethod |
| def find_module(cls, fullname, path=None): |
| """Find a frozen module. |
| |
| This method is deprecated. Use find_spec() instead. |
| |
| """ |
| return cls if _imp.is_frozen(fullname) else None |
| |
| @staticmethod |
| def exec_module(module): |
| name = module.__spec__.name |
| if not _imp.is_frozen(name): |
| raise ImportError('{!r} is not a frozen module'.format(name), |
| name=name) |
| code = _call_with_frames_removed(_imp.get_frozen_object, name) |
| exec(code, module.__dict__) |
| |
| @classmethod |
| def load_module(cls, fullname): |
| """Load a frozen module. |
| |
| This method is deprecated. Use exec_module() instead. |
| |
| """ |
| return _load_module_shim(cls, fullname) |
| |
| @classmethod |
| @_requires_frozen |
| def get_code(cls, fullname): |
| """Return the code object for the frozen module.""" |
| return _imp.get_frozen_object(fullname) |
| |
| @classmethod |
| @_requires_frozen |
| def get_source(cls, fullname): |
| """Return None as frozen modules do not have source code.""" |
| return None |
| |
| @classmethod |
| @_requires_frozen |
| def is_package(cls, fullname): |
| """Return True if the frozen module is a package.""" |
| 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 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 init_module_attrs() 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 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 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 == '': |
| path = _os.getcwd() |
| 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: |
| |
| """Context manager for the import lock.""" |
| |
| def __enter__(self): |
| """Acquire the import lock.""" |
| _imp.acquire_lock() |
| |
| def __exit__(self, exc_type, exc_value, exc_traceback): |
| """Release the import lock regardless of any raised exceptions.""" |
| _imp.release_lock() |
| |
| |
| def _resolve_name(name, package, level): |
| """Resolve a relative module name to an absolute one.""" |
| bits = package.rsplit('.', level - 1) |
| if len(bits) < level: |
| raise ValueError('attempted relative import beyond top-level package') |
| base = bits[0] |
| return '{}.{}'.format(base, name) if name else base |
| |
| |
| def _find_spec_legacy(finder, name, path): |
| # This would be a good place for a DeprecationWarning if |
| # we ended up going that route. |
| loader = finder.find_module(name, path) |
| if loader is None: |
| return None |
| return spec_from_loader(name, loader) |
| |
| |
| def _find_spec(name, path, target=None): |
| """Find a module's loader.""" |
| if not sys.meta_path: |
| _warnings.warn('sys.meta_path is empty', ImportWarning) |
| # We check sys.modules here for the reload case. While a passed-in |
| # target will usually indicate a reload there is no guarantee, whereas |
| # sys.modules provides one. |
| is_reload = name in sys.modules |
| for finder in sys.meta_path: |
| with _ImportLockContext(): |
| try: |
| find_spec = finder.find_spec |
| except AttributeError: |
| spec = _find_spec_legacy(finder, name, path) |
| if spec is None: |
| continue |
| else: |
| spec = find_spec(name, path, target) |
| if spec is not None: |
| # The parent import may have already imported this module. |
| if not is_reload and name in sys.modules: |
| module = sys.modules[name] |
| try: |
| __spec__ = module.__spec__ |
| except AttributeError: |
| # We use the found spec since that is the one that |
| # we would have used if the parent module hadn't |
| # beaten us to the punch. |
| return spec |
| else: |
| if __spec__ is None: |
| return spec |
| else: |
| return __spec__ |
| else: |
| return spec |
| else: |
| return None |
| |
| |
| def _sanity_check(name, package, level): |
| """Verify arguments are "sane".""" |
| if not isinstance(name, str): |
| raise TypeError('module name must be str, not {}'.format(type(name))) |
| if level < 0: |
| raise ValueError('level must be >= 0') |
| if package: |
| if not isinstance(package, str): |
| raise TypeError('__package__ not set to a string') |
| elif package not in sys.modules: |
| msg = ('Parent module {!r} not loaded, cannot perform relative ' |
| 'import') |
| raise SystemError(msg.format(package)) |
| if not name and level == 0: |
| raise ValueError('Empty module name') |
| |
| |
| _ERR_MSG_PREFIX = 'No module named ' |
| _ERR_MSG = _ERR_MSG_PREFIX + '{!r}' |
| |
| def _find_and_load_unlocked(name, import_): |
| path = None |
| parent = name.rpartition('.')[0] |
| if parent: |
| if parent not in sys.modules: |
| _call_with_frames_removed(import_, parent) |
| # Crazy side-effects! |
| if name in sys.modules: |
| return sys.modules[name] |
| parent_module = sys.modules[parent] |
| try: |
| path = parent_module.__path__ |
| except AttributeError: |
| msg = (_ERR_MSG + '; {!r} is not a package').format(name, parent) |
| raise ImportError(msg, name=name) |
| spec = _find_spec(name, path) |
| if spec is None: |
| raise ImportError(_ERR_MSG.format(name), name=name) |
| else: |
| module = _SpecMethods(spec)._load_unlocked() |
| if parent: |
| # Set the module as an attribute on its parent. |
| parent_module = sys.modules[parent] |
| setattr(parent_module, name.rpartition('.')[2], module) |
| return module |
| |
| |
| def _find_and_load(name, import_): |
| """Find and load the module, and release the import lock.""" |
| with _ModuleLockManager(name): |
| return _find_and_load_unlocked(name, import_) |
| |
| |
| def _gcd_import(name, package=None, level=0): |
| """Import and return the module based on its name, the package the call is |
| being made from, and the level adjustment. |
| |
| This function represents the greatest common denominator of functionality |
| between import_module and __import__. This includes setting __package__ if |
| the loader did not. |
| |
| """ |
| _sanity_check(name, package, level) |
| if level > 0: |
| name = _resolve_name(name, package, level) |
| _imp.acquire_lock() |
| if name not in sys.modules: |
| return _find_and_load(name, _gcd_import) |
| module = sys.modules[name] |
| if module is None: |
| _imp.release_lock() |
| message = ('import of {} halted; ' |
| 'None in sys.modules'.format(name)) |
| raise ImportError(message, name=name) |
| _lock_unlock_module(name) |
| return module |
| |
| def _handle_fromlist(module, fromlist, import_): |
| """Figure out what __import__ should return. |
| |
| The import_ parameter is a callable which takes the name of module to |
| import. It is required to decouple the function from assuming importlib's |
| import implementation is desired. |
| |
| """ |
| # The hell that is fromlist ... |
| # If a package was imported, try to import stuff from fromlist. |
| if hasattr(module, '__path__'): |
| if '*' in fromlist: |
| fromlist = list(fromlist) |
| fromlist.remove('*') |
| if hasattr(module, '__all__'): |
| fromlist.extend(module.__all__) |
| for x in fromlist: |
| if not hasattr(module, x): |
| from_name = '{}.{}'.format(module.__name__, x) |
| try: |
| _call_with_frames_removed(import_, from_name) |
| except ImportError as exc: |
| # Backwards-compatibility dictates we ignore failed |
| # imports triggered by fromlist for modules that don't |
| # exist. |
| if str(exc).startswith(_ERR_MSG_PREFIX): |
| if exc.name == from_name: |
| continue |
| raise |
| return module |
| |
| |
| def _calc___package__(globals): |
| """Calculate what __package__ should be. |
| |
| __package__ is not guaranteed to be defined or could be set to None |
| to represent that its proper value is unknown. |
| |
| """ |
| package = globals.get('__package__') |
| if package is None: |
| package = globals['__name__'] |
| if '__path__' not in globals: |
| package = package.rpartition('.')[0] |
| 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. |
| |
| The 'globals' argument is used to infer where the import is occuring from |
| to handle relative imports. The 'locals' argument is ignored. The |
| 'fromlist' argument specifies what should exist as attributes on the module |
| being imported (e.g. ``from module import <fromlist>``). The 'level' |
| argument represents the package location to import from in a relative |
| import (e.g. ``from ..pkg import mod`` would have a 'level' of 2). |
| |
| """ |
| if level == 0: |
| module = _gcd_import(name) |
| else: |
| globals_ = globals if globals is not None else {} |
| package = _calc___package__(globals_) |
| module = _gcd_import(name, package, level) |
| if not fromlist: |
| # Return up to the first dot in 'name'. This is complicated by the fact |
| # that 'name' may be relative. |
| if level == 0: |
| return _gcd_import(name.partition('.')[0]) |
| elif not name: |
| return module |
| else: |
| # Figure out where to slice the module's name up to the first dot |
| # in 'name'. |
| cut_off = len(name) - len(name.partition('.')[0]) |
| # Slice end needs to be positive to alleviate need to special-case |
| # when ``'.' not in name``. |
| return sys.modules[module.__name__[:len(module.__name__)-cut_off]] |
| else: |
| return _handle_fromlist(module, fromlist, _gcd_import) |
| |
| |
| def _builtin_from_name(name): |
| spec = BuiltinImporter.find_spec(name) |
| if spec is None: |
| raise ImportError('no built-in module named ' + name) |
| methods = _SpecMethods(spec) |
| return methods._load_unlocked() |
| |
| |
| def _setup(sys_module, _imp_module): |
| """Setup importlib by importing needed built-in modules and injecting them |
| into the global namespace. |
| |
| As sys is needed for sys.modules access and _imp is needed to load built-in |
| modules, those two modules must be explicitly passed in. |
| |
| """ |
| global _imp, sys, BYTECODE_SUFFIXES |
| _imp = _imp_module |
| sys = sys_module |
| |
| if sys.flags.optimize: |
| BYTECODE_SUFFIXES = OPTIMIZED_BYTECODE_SUFFIXES |
| else: |
| BYTECODE_SUFFIXES = DEBUG_BYTECODE_SUFFIXES |
| |
| # Set up the spec for existing builtin/frozen modules. |
| module_type = type(sys) |
| for name, module in sys.modules.items(): |
| if isinstance(module, module_type): |
| if name in sys.builtin_module_names: |
| loader = BuiltinImporter |
| elif _imp.is_frozen(name): |
| loader = FrozenImporter |
| else: |
| continue |
| spec = _spec_from_module(module, loader) |
| methods = _SpecMethods(spec) |
| methods.init_module_attrs(module) |
| |
| # Directly load built-in modules needed during bootstrap. |
| self_module = sys.modules[__name__] |
| for builtin_name in ('_io', '_warnings', 'builtins', 'marshal'): |
| 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') |
| except ImportError: |
| # Python was built without threads |
| thread_module = None |
| setattr(self_module, '_thread', thread_module) |
| |
| # Directly load the _weakref module (needed during bootstrap). |
| 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) |