| """Core implementation of path-based 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 regen-importlib` followed by `make` in order to get the frozen version |
| # of the module updated. 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_STR_KEY = 'win', |
| _CASE_INSENSITIVE_PLATFORMS_BYTES_KEY = 'cygwin', 'darwin' |
| _CASE_INSENSITIVE_PLATFORMS = (_CASE_INSENSITIVE_PLATFORMS_BYTES_KEY |
| + _CASE_INSENSITIVE_PLATFORMS_STR_KEY) |
| |
| |
| def _make_relax_case(): |
| if sys.platform.startswith(_CASE_INSENSITIVE_PLATFORMS): |
| if sys.platform.startswith(_CASE_INSENSITIVE_PLATFORMS_STR_KEY): |
| key = 'PYTHONCASEOK' |
| else: |
| key = b'PYTHONCASEOK' |
| |
| def _relax_case(): |
| """True if filenames must be checked case-insensitively and ignore environment flags are not set.""" |
| return not sys.flags.ignore_environment and key in _os.environ |
| else: |
| def _relax_case(): |
| """True if filenames must be checked case-insensitively.""" |
| return False |
| return _relax_case |
| |
| |
| def _pack_uint32(x): |
| """Convert a 32-bit integer to little-endian.""" |
| return (int(x) & 0xFFFFFFFF).to_bytes(4, 'little') |
| |
| |
| def _unpack_uint32(data): |
| """Convert 4 bytes in little-endian to an integer.""" |
| assert len(data) == 4 |
| return int.from_bytes(data, 'little') |
| |
| def _unpack_uint16(data): |
| """Convert 2 bytes in little-endian to an integer.""" |
| assert len(data) == 2 |
| return int.from_bytes(data, '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 _path_isabs(path): |
| """Replacement for os.path.isabs. |
| |
| Considers a Windows drive-relative path (no drive, but starts with slash) to |
| still be "absolute". |
| """ |
| return path.startswith(path_separators) or path[1:3] in _pathseps_with_colon |
| |
| |
| 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 |
| |
| |
| _code_type = type(_write_atomic.__code__) |
| |
| |
| # 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. |
| # |
| # 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 3.0b1: 3131 (lexical exception stacking, including POP_EXCEPT |
| #3021) |
| # Python 3.1a1: 3141 (optimize list, set and dict comprehensions: |
| # change LIST_APPEND and SET_ADD, add MAP_ADD #2183) |
| # Python 3.1a1: 3151 (optimize conditional branches: |
| # introduce POP_JUMP_IF_FALSE and POP_JUMP_IF_TRUE |
| #4715) |
| # Python 3.2a1: 3160 (add SETUP_WITH #6101) |
| # tag: cpython-32 |
| # Python 3.2a2: 3170 (add DUP_TOP_TWO, remove DUP_TOPX and ROT_FOUR #9225) |
| # tag: cpython-32 |
| # Python 3.2a3 3180 (add DELETE_DEREF #4617) |
| # Python 3.3a1 3190 (__class__ super closure changed) |
| # Python 3.3a1 3200 (PEP 3155 __qualname__ added #13448) |
| # Python 3.3a1 3210 (added size modulo 2**32 to the pyc header #13645) |
| # Python 3.3a2 3220 (changed PEP 380 implementation #14230) |
| # Python 3.3a4 3230 (revert changes to implicit __class__ closure #14857) |
| # Python 3.4a1 3250 (evaluate positional default arguments before |
| # keyword-only defaults #16967) |
| # Python 3.4a1 3260 (add LOAD_CLASSDEREF; allow locals of class to override |
| # free vars #17853) |
| # Python 3.4a1 3270 (various tweaks to the __class__ closure #12370) |
| # Python 3.4a1 3280 (remove implicit class argument) |
| # Python 3.4a4 3290 (changes to __qualname__ computation #19301) |
| # Python 3.4a4 3300 (more changes to __qualname__ computation #19301) |
| # Python 3.4rc2 3310 (alter __qualname__ computation #20625) |
| # Python 3.5a1 3320 (PEP 465: Matrix multiplication operator #21176) |
| # Python 3.5b1 3330 (PEP 448: Additional Unpacking Generalizations #2292) |
| # Python 3.5b2 3340 (fix dictionary display evaluation order #11205) |
| # Python 3.5b3 3350 (add GET_YIELD_FROM_ITER opcode #24400) |
| # Python 3.5.2 3351 (fix BUILD_MAP_UNPACK_WITH_CALL opcode #27286) |
| # Python 3.6a0 3360 (add FORMAT_VALUE opcode #25483) |
| # Python 3.6a1 3361 (lineno delta of code.co_lnotab becomes signed #26107) |
| # Python 3.6a2 3370 (16 bit wordcode #26647) |
| # Python 3.6a2 3371 (add BUILD_CONST_KEY_MAP opcode #27140) |
| # Python 3.6a2 3372 (MAKE_FUNCTION simplification, remove MAKE_CLOSURE |
| # #27095) |
| # Python 3.6b1 3373 (add BUILD_STRING opcode #27078) |
| # Python 3.6b1 3375 (add SETUP_ANNOTATIONS and STORE_ANNOTATION opcodes |
| # #27985) |
| # Python 3.6b1 3376 (simplify CALL_FUNCTIONs & BUILD_MAP_UNPACK_WITH_CALL |
| #27213) |
| # Python 3.6b1 3377 (set __class__ cell from type.__new__ #23722) |
| # Python 3.6b2 3378 (add BUILD_TUPLE_UNPACK_WITH_CALL #28257) |
| # Python 3.6rc1 3379 (more thorough __class__ validation #23722) |
| # Python 3.7a1 3390 (add LOAD_METHOD and CALL_METHOD opcodes #26110) |
| # Python 3.7a2 3391 (update GET_AITER #31709) |
| # Python 3.7a4 3392 (PEP 552: Deterministic pycs #31650) |
| # Python 3.7b1 3393 (remove STORE_ANNOTATION opcode #32550) |
| # Python 3.7b5 3394 (restored docstring as the first stmt in the body; |
| # this might affected the first line number #32911) |
| # Python 3.8a1 3400 (move frame block handling to compiler #17611) |
| # Python 3.8a1 3401 (add END_ASYNC_FOR #33041) |
| # Python 3.8a1 3410 (PEP570 Python Positional-Only Parameters #36540) |
| # Python 3.8b2 3411 (Reverse evaluation order of key: value in dict |
| # comprehensions #35224) |
| # Python 3.8b2 3412 (Swap the position of positional args and positional |
| # only args in ast.arguments #37593) |
| # Python 3.8b4 3413 (Fix "break" and "continue" in "finally" #37830) |
| # Python 3.9a0 3420 (add LOAD_ASSERTION_ERROR #34880) |
| # Python 3.9a0 3421 (simplified bytecode for with blocks #32949) |
| # Python 3.9a0 3422 (remove BEGIN_FINALLY, END_FINALLY, CALL_FINALLY, POP_FINALLY bytecodes #33387) |
| # Python 3.9a2 3423 (add IS_OP, CONTAINS_OP and JUMP_IF_NOT_EXC_MATCH bytecodes #39156) |
| # Python 3.9a2 3424 (simplify bytecodes for *value unpacking) |
| # Python 3.9a2 3425 (simplify bytecodes for **value unpacking) |
| |
| # |
| # 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). |
| # |
| # Whenever MAGIC_NUMBER is changed, the ranges in the magic_values array |
| # in PC/launcher.c must also be updated. |
| |
| MAGIC_NUMBER = (3425).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 |
| path = _os.fspath(path) |
| 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) |
| filename = almost_filename + BYTECODE_SUFFIXES[0] |
| if sys.pycache_prefix is not None: |
| # We need an absolute path to the py file to avoid the possibility of |
| # collisions within sys.pycache_prefix, if someone has two different |
| # `foo/bar.py` on their system and they import both of them using the |
| # same sys.pycache_prefix. Let's say sys.pycache_prefix is |
| # `C:\Bytecode`; the idea here is that if we get `Foo\Bar`, we first |
| # make it absolute (`C:\Somewhere\Foo\Bar`), then make it root-relative |
| # (`Somewhere\Foo\Bar`), so we end up placing the bytecode file in an |
| # unambiguous `C:\Bytecode\Somewhere\Foo\Bar\`. |
| if not _path_isabs(head): |
| head = _path_join(_os.getcwd(), head) |
| |
| # Strip initial drive from a Windows path. We know we have an absolute |
| # path here, so the second part of the check rules out a POSIX path that |
| # happens to contain a colon at the second character. |
| if head[1] == ':' and head[0] not in path_separators: |
| head = head[2:] |
| |
| # Strip initial path separator from `head` to complete the conversion |
| # back to a root-relative path before joining. |
| return _path_join( |
| sys.pycache_prefix, |
| head.lstrip(path_separators), |
| filename, |
| ) |
| return _path_join(head, _PYCACHE, filename) |
| |
| |
| 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') |
| path = _os.fspath(path) |
| head, pycache_filename = _path_split(path) |
| found_in_pycache_prefix = False |
| if sys.pycache_prefix is not None: |
| stripped_path = sys.pycache_prefix.rstrip(path_separators) |
| if head.startswith(stripped_path + path_sep): |
| head = head[len(stripped_path):] |
| found_in_pycache_prefix = True |
| if not found_in_pycache_prefix: |
| head, pycache = _path_split(head) |
| if pycache != _PYCACHE: |
| raise ValueError(f'{_PYCACHE} not bottom-level directory in ' |
| f'{path!r}') |
| dot_count = pycache_filename.count('.') |
| if dot_count not in {2, 3}: |
| raise ValueError(f'expected only 2 or 3 dots in {pycache_filename!r}') |
| elif dot_count == 3: |
| optimization = pycache_filename.rsplit('.', 2)[-2] |
| if not optimization.startswith(_OPT): |
| raise ValueError("optimization portion of filename does not start " |
| f"with {_OPT!r}") |
| opt_level = optimization[len(_OPT):] |
| if not opt_level.isalnum(): |
| raise ValueError(f"optimization level {optimization!r} is not an " |
| "alphanumeric value") |
| 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 _get_cached(filename): |
| if filename.endswith(tuple(SOURCE_SUFFIXES)): |
| try: |
| return cache_from_source(filename) |
| except NotImplementedError: |
| pass |
| elif filename.endswith(tuple(BYTECODE_SUFFIXES)): |
| return filename |
| else: |
| return None |
| |
| |
| 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 _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 for %s cannot handle %s' % |
| (self.name, name), name=name) |
| return method(self, name, *args, **kwargs) |
| try: |
| _wrap = _bootstrap._wrap |
| except NameError: |
| # XXX yuck |
| def _wrap(new, old): |
| for replace in ['__module__', '__name__', '__qualname__', '__doc__']: |
| if hasattr(old, replace): |
| setattr(new, replace, getattr(old, replace)) |
| new.__dict__.update(old.__dict__) |
| _wrap(_check_name_wrapper, method) |
| return _check_name_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 _classify_pyc(data, name, exc_details): |
| """Perform basic validity checking of a pyc header and return the flags field, |
| which determines how the pyc should be further validated against the source. |
| |
| *data* is the contents of the pyc file. (Only the first 16 bytes are |
| required, though.) |
| |
| *name* is the name of the module being imported. It is used for logging. |
| |
| *exc_details* is a dictionary passed to ImportError if it raised for |
| improved debugging. |
| |
| ImportError is raised when the magic number is incorrect or when the flags |
| field is invalid. EOFError is raised when the data is found to be truncated. |
| |
| """ |
| magic = data[:4] |
| if magic != MAGIC_NUMBER: |
| message = f'bad magic number in {name!r}: {magic!r}' |
| _bootstrap._verbose_message('{}', message) |
| raise ImportError(message, **exc_details) |
| if len(data) < 16: |
| message = f'reached EOF while reading pyc header of {name!r}' |
| _bootstrap._verbose_message('{}', message) |
| raise EOFError(message) |
| flags = _unpack_uint32(data[4:8]) |
| # Only the first two flags are defined. |
| if flags & ~0b11: |
| message = f'invalid flags {flags!r} in {name!r}' |
| raise ImportError(message, **exc_details) |
| return flags |
| |
| |
| def _validate_timestamp_pyc(data, source_mtime, source_size, name, |
| exc_details): |
| """Validate a pyc against the source last-modified time. |
| |
| *data* is the contents of the pyc file. (Only the first 16 bytes are |
| required.) |
| |
| *source_mtime* is the last modified timestamp of the source file. |
| |
| *source_size* is None or the size of the source file in bytes. |
| |
| *name* is the name of the module being imported. It is used for logging. |
| |
| *exc_details* is a dictionary passed to ImportError if it raised for |
| improved debugging. |
| |
| An ImportError is raised if the bytecode is stale. |
| |
| """ |
| if _unpack_uint32(data[8:12]) != (source_mtime & 0xFFFFFFFF): |
| message = f'bytecode is stale for {name!r}' |
| _bootstrap._verbose_message('{}', message) |
| raise ImportError(message, **exc_details) |
| if (source_size is not None and |
| _unpack_uint32(data[12:16]) != (source_size & 0xFFFFFFFF)): |
| raise ImportError(f'bytecode is stale for {name!r}', **exc_details) |
| |
| |
| def _validate_hash_pyc(data, source_hash, name, exc_details): |
| """Validate a hash-based pyc by checking the real source hash against the one in |
| the pyc header. |
| |
| *data* is the contents of the pyc file. (Only the first 16 bytes are |
| required.) |
| |
| *source_hash* is the importlib.util.source_hash() of the source file. |
| |
| *name* is the name of the module being imported. It is used for logging. |
| |
| *exc_details* is a dictionary passed to ImportError if it raised for |
| improved debugging. |
| |
| An ImportError is raised if the bytecode is stale. |
| |
| """ |
| if data[8:16] != source_hash: |
| raise ImportError( |
| f'hash in bytecode doesn\'t match hash of source {name!r}', |
| **exc_details, |
| ) |
| |
| |
| def _compile_bytecode(data, name=None, bytecode_path=None, source_path=None): |
| """Compile bytecode as found in a pyc.""" |
| code = marshal.loads(data) |
| if isinstance(code, _code_type): |
| _bootstrap._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_timestamp_pyc(code, mtime=0, source_size=0): |
| "Produce the data for a timestamp-based pyc." |
| data = bytearray(MAGIC_NUMBER) |
| data.extend(_pack_uint32(0)) |
| data.extend(_pack_uint32(mtime)) |
| data.extend(_pack_uint32(source_size)) |
| data.extend(marshal.dumps(code)) |
| return data |
| |
| |
| def _code_to_hash_pyc(code, source_hash, checked=True): |
| "Produce the data for a hash-based pyc." |
| data = bytearray(MAGIC_NUMBER) |
| flags = 0b1 | checked << 1 |
| data.extend(_pack_uint32(flags)) |
| assert len(source_hash) == 8 |
| data.extend(source_hash) |
| 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 ####################################################### |
| |
| _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 |
| else: |
| location = _os.fspath(location) |
| |
| # 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 = _bootstrap.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 |
| |
| |
| # Loaders ##################################################################### |
| |
| 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='%d.%d' % sys.version_info[:2]) |
| 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 = _bootstrap.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__)) |
| _bootstrap._call_with_frames_removed(exec, code, module.__dict__) |
| |
| def load_module(self, fullname): |
| """This module is deprecated.""" |
| return _bootstrap._load_module_shim(self, fullname) |
| |
| |
| class SourceLoader(_LoaderBasics): |
| |
| def path_mtime(self, path): |
| """Optional method that returns the modification time (an int) for the |
| specified path (a str). |
| |
| Raises OSError when the path cannot be handled. |
| """ |
| raise OSError |
| |
| def path_stats(self, path): |
| """Optional method returning a metadata dict for the specified |
| path (a 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 OSError 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 _bootstrap._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 |
| source_bytes = None |
| source_hash = None |
| hash_based = False |
| check_source = True |
| try: |
| bytecode_path = cache_from_source(source_path) |
| except NotImplementedError: |
| bytecode_path = None |
| else: |
| try: |
| st = self.path_stats(source_path) |
| except OSError: |
| pass |
| else: |
| source_mtime = int(st['mtime']) |
| try: |
| data = self.get_data(bytecode_path) |
| except OSError: |
| pass |
| else: |
| exc_details = { |
| 'name': fullname, |
| 'path': bytecode_path, |
| } |
| try: |
| flags = _classify_pyc(data, fullname, exc_details) |
| bytes_data = memoryview(data)[16:] |
| hash_based = flags & 0b1 != 0 |
| if hash_based: |
| check_source = flags & 0b10 != 0 |
| if (_imp.check_hash_based_pycs != 'never' and |
| (check_source or |
| _imp.check_hash_based_pycs == 'always')): |
| source_bytes = self.get_data(source_path) |
| source_hash = _imp.source_hash( |
| _RAW_MAGIC_NUMBER, |
| source_bytes, |
| ) |
| _validate_hash_pyc(data, source_hash, fullname, |
| exc_details) |
| else: |
| _validate_timestamp_pyc( |
| data, |
| source_mtime, |
| st['size'], |
| fullname, |
| exc_details, |
| ) |
| except (ImportError, EOFError): |
| pass |
| else: |
| _bootstrap._verbose_message('{} matches {}', bytecode_path, |
| source_path) |
| return _compile_bytecode(bytes_data, name=fullname, |
| bytecode_path=bytecode_path, |
| source_path=source_path) |
| if source_bytes is None: |
| source_bytes = self.get_data(source_path) |
| code_object = self.source_to_code(source_bytes, source_path) |
| _bootstrap._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): |
| if hash_based: |
| if source_hash is None: |
| source_hash = _imp.source_hash(source_bytes) |
| data = _code_to_hash_pyc(code_object, source_hash, check_source) |
| else: |
| data = _code_to_timestamp_pyc(code_object, source_mtime, |
| len(source_bytes)) |
| try: |
| self._cache_bytecode(source_path, bytecode_path, data) |
| 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.""" |
| if isinstance(self, (SourceLoader, ExtensionFileLoader)): |
| with _io.open_code(str(path)) as file: |
| return file.read() |
| else: |
| with _io.FileIO(path, 'r') as file: |
| return file.read() |
| |
| # ResourceReader ABC API. |
| |
| @_check_name |
| def get_resource_reader(self, module): |
| if self.is_package(module): |
| return self |
| return None |
| |
| def open_resource(self, resource): |
| path = _path_join(_path_split(self.path)[0], resource) |
| return _io.FileIO(path, 'r') |
| |
| def resource_path(self, resource): |
| if not self.is_resource(resource): |
| raise FileNotFoundError |
| path = _path_join(_path_split(self.path)[0], resource) |
| return path |
| |
| def is_resource(self, name): |
| if path_sep in name: |
| return False |
| path = _path_join(_path_split(self.path)[0], name) |
| return _path_isfile(path) |
| |
| def contents(self): |
| return iter(_os.listdir(_path_split(self.path)[0])) |
| |
| |
| 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. |
| _bootstrap._verbose_message('could not create {!r}: {!r}', |
| parent, exc) |
| return |
| try: |
| _write_atomic(path, data, _mode) |
| _bootstrap._verbose_message('created {!r}', path) |
| except OSError as exc: |
| # Same as above: just don't write the bytecode. |
| _bootstrap._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) |
| # Call _classify_pyc to do basic validation of the pyc but ignore the |
| # result. There's no source to check against. |
| exc_details = { |
| 'name': fullname, |
| 'path': path, |
| } |
| _classify_pyc(data, fullname, exc_details) |
| return _compile_bytecode( |
| memoryview(data)[16:], |
| 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(FileLoader, _LoaderBasics): |
| |
| """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) |
| |
| def create_module(self, spec): |
| """Create an unitialized extension module""" |
| module = _bootstrap._call_with_frames_removed( |
| _imp.create_dynamic, spec) |
| _bootstrap._verbose_message('extension module {!r} loaded from {!r}', |
| spec.name, self.path) |
| return module |
| |
| def exec_module(self, module): |
| """Initialize an extension module""" |
| _bootstrap._call_with_frames_removed(_imp.exec_dynamic, module) |
| _bootstrap._verbose_message('extension module {!r} executed from {!r}', |
| self.name, self.path) |
| |
| 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 __getitem__(self, index): |
| return self._recalculate()[index] |
| |
| def __setitem__(self, index, path): |
| self._path[index] = path |
| |
| 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. |
| _bootstrap._verbose_message('namespace module loaded with path {!r}', |
| self._path) |
| return _bootstrap._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 name, finder in list(sys.path_importer_cache.items()): |
| if finder is None: |
| del sys.path_importer_cache[name] |
| elif hasattr(finder, 'invalidate_caches'): |
| finder.invalidate_caches() |
| |
| @classmethod |
| def _path_hooks(cls, path): |
| """Search sys.path_hooks for a finder for 'path'.""" |
| 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 _bootstrap.spec_from_loader(fullname, loader) |
| spec = _bootstrap.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 = _bootstrap.ModuleSpec(fullname, None) |
| spec.submodule_search_locations = namespace_path |
| return spec |
| |
| @classmethod |
| def find_spec(cls, fullname, path=None, target=None): |
| """Try to find a spec for 'fullname' on sys.path or 'path'. |
| |
| The search is 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 = None |
| 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 |
| |
| @classmethod |
| def find_distributions(cls, *args, **kwargs): |
| """ |
| Find distributions. |
| |
| Return an iterable of all Distribution instances capable of |
| loading the metadata for packages matching ``context.name`` |
| (or all names if ``None`` indicated) along the paths in the list |
| of directories ``context.path``. |
| """ |
| from importlib.metadata import MetadataPathFinder |
| return MetadataPathFinder.find_distributions(*args, **kwargs) |
| |
| |
| 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 spec for the specified module. |
| |
| Returns the matching spec, or None if not found. |
| """ |
| 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) |
| _bootstrap._verbose_message('trying {}', 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: |
| _bootstrap._verbose_message('possible namespace for {}', base_path) |
| spec = _bootstrap.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 setup ############################################################### |
| |
| 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 |
| |
| |
| 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 _setup(_bootstrap_module): |
| """Setup the path-based importers for importlib by importing needed |
| built-in modules and injecting them into the global namespace. |
| |
| Other components are extracted from the core bootstrap module. |
| |
| """ |
| global sys, _imp, _bootstrap |
| _bootstrap = _bootstrap_module |
| sys = _bootstrap.sys |
| _imp = _bootstrap._imp |
| |
| self_module = sys.modules[__name__] |
| |
| # 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 = _bootstrap._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)) |
| setattr(self_module, '_pathseps_with_colon', {f':{s}' for s in path_separators}) |
| |
| # Directly load built-in modules needed during bootstrap. |
| builtin_names = ['_io', '_warnings', 'marshal'] |
| if builtin_os == 'nt': |
| builtin_names.append('winreg') |
| for builtin_name in builtin_names: |
| if builtin_name not in sys.modules: |
| builtin_module = _bootstrap._builtin_from_name(builtin_name) |
| else: |
| builtin_module = sys.modules[builtin_name] |
| setattr(self_module, builtin_name, builtin_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(_bootstrap_module): |
| """Install the path-based import components.""" |
| _setup(_bootstrap_module) |
| supported_loaders = _get_supported_file_loaders() |
| sys.path_hooks.extend([FileFinder.path_hook(*supported_loaders)]) |
| sys.meta_path.append(PathFinder) |
