mirror of https://github.com/python/cpython
1616 lines
60 KiB
Python
1616 lines
60 KiB
Python
"""Core implementation of path-based import.
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This module is NOT meant to be directly imported! It has been designed such
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that it can be bootstrapped into Python as the implementation of import. As
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such it requires the injection of specific modules and attributes in order to
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work. One should use importlib as the public-facing version of this module.
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"""
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# IMPORTANT: Whenever making changes to this module, be sure to run a top-level
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# `make regen-importlib` followed by `make` in order to get the frozen version
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# of the module updated. Not doing so will result in the Makefile to fail for
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# all others who don't have a ./python around to freeze the module in the early
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# stages of compilation.
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#
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# See importlib._setup() for what is injected into the global namespace.
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# When editing this code be aware that code executed at import time CANNOT
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# reference any injected objects! This includes not only global code but also
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# anything specified at the class level.
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# Bootstrap-related code ######################################################
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_CASE_INSENSITIVE_PLATFORMS_STR_KEY = 'win',
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_CASE_INSENSITIVE_PLATFORMS_BYTES_KEY = 'cygwin', 'darwin'
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_CASE_INSENSITIVE_PLATFORMS = (_CASE_INSENSITIVE_PLATFORMS_BYTES_KEY
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+ _CASE_INSENSITIVE_PLATFORMS_STR_KEY)
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def _make_relax_case():
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if sys.platform.startswith(_CASE_INSENSITIVE_PLATFORMS):
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if sys.platform.startswith(_CASE_INSENSITIVE_PLATFORMS_STR_KEY):
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key = 'PYTHONCASEOK'
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else:
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key = b'PYTHONCASEOK'
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def _relax_case():
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"""True if filenames must be checked case-insensitively and ignore environment flags are not set."""
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return not sys.flags.ignore_environment and key in _os.environ
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else:
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def _relax_case():
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"""True if filenames must be checked case-insensitively."""
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return False
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return _relax_case
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def _pack_uint32(x):
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"""Convert a 32-bit integer to little-endian."""
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return (int(x) & 0xFFFFFFFF).to_bytes(4, 'little')
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def _unpack_uint32(data):
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"""Convert 4 bytes in little-endian to an integer."""
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assert len(data) == 4
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return int.from_bytes(data, 'little')
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def _unpack_uint16(data):
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"""Convert 2 bytes in little-endian to an integer."""
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assert len(data) == 2
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return int.from_bytes(data, 'little')
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def _path_join(*path_parts):
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"""Replacement for os.path.join()."""
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return path_sep.join([part.rstrip(path_separators)
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for part in path_parts if part])
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def _path_split(path):
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"""Replacement for os.path.split()."""
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if len(path_separators) == 1:
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front, _, tail = path.rpartition(path_sep)
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return front, tail
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for x in reversed(path):
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if x in path_separators:
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front, tail = path.rsplit(x, maxsplit=1)
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return front, tail
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return '', path
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def _path_stat(path):
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"""Stat the path.
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Made a separate function to make it easier to override in experiments
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(e.g. cache stat results).
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"""
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return _os.stat(path)
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def _path_is_mode_type(path, mode):
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"""Test whether the path is the specified mode type."""
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try:
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stat_info = _path_stat(path)
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except OSError:
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return False
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return (stat_info.st_mode & 0o170000) == mode
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def _path_isfile(path):
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"""Replacement for os.path.isfile."""
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return _path_is_mode_type(path, 0o100000)
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def _path_isdir(path):
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"""Replacement for os.path.isdir."""
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if not path:
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path = _os.getcwd()
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return _path_is_mode_type(path, 0o040000)
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def _path_isabs(path):
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"""Replacement for os.path.isabs.
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Considers a Windows drive-relative path (no drive, but starts with slash) to
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still be "absolute".
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"""
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return path.startswith(path_separators) or path[1:3] in _pathseps_with_colon
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def _write_atomic(path, data, mode=0o666):
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"""Best-effort function to write data to a path atomically.
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Be prepared to handle a FileExistsError if concurrent writing of the
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temporary file is attempted."""
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# id() is used to generate a pseudo-random filename.
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path_tmp = '{}.{}'.format(path, id(path))
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fd = _os.open(path_tmp,
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_os.O_EXCL | _os.O_CREAT | _os.O_WRONLY, mode & 0o666)
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try:
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# We first write data to a temporary file, and then use os.replace() to
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# perform an atomic rename.
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with _io.FileIO(fd, 'wb') as file:
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file.write(data)
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_os.replace(path_tmp, path)
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except OSError:
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try:
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_os.unlink(path_tmp)
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except OSError:
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pass
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raise
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_code_type = type(_write_atomic.__code__)
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# Finder/loader utility code ###############################################
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# Magic word to reject .pyc files generated by other Python versions.
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# It should change for each incompatible change to the bytecode.
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#
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# The value of CR and LF is incorporated so if you ever read or write
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# a .pyc file in text mode the magic number will be wrong; also, the
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# Apple MPW compiler swaps their values, botching string constants.
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#
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# There were a variety of old schemes for setting the magic number.
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# The current working scheme is to increment the previous value by
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# 10.
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#
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# Starting with the adoption of PEP 3147 in Python 3.2, every bump in magic
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# number also includes a new "magic tag", i.e. a human readable string used
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# to represent the magic number in __pycache__ directories. When you change
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# the magic number, you must also set a new unique magic tag. Generally this
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# can be named after the Python major version of the magic number bump, but
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# it can really be anything, as long as it's different than anything else
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# that's come before. The tags are included in the following table, starting
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# with Python 3.2a0.
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#
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# Known values:
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# Python 1.5: 20121
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# Python 1.5.1: 20121
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# Python 1.5.2: 20121
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# Python 1.6: 50428
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# Python 2.0: 50823
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# Python 2.0.1: 50823
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# Python 2.1: 60202
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# Python 2.1.1: 60202
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# Python 2.1.2: 60202
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# Python 2.2: 60717
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# Python 2.3a0: 62011
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# Python 2.3a0: 62021
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# Python 2.3a0: 62011 (!)
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# Python 2.4a0: 62041
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# Python 2.4a3: 62051
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# Python 2.4b1: 62061
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# Python 2.5a0: 62071
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# Python 2.5a0: 62081 (ast-branch)
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# Python 2.5a0: 62091 (with)
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# Python 2.5a0: 62092 (changed WITH_CLEANUP opcode)
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# Python 2.5b3: 62101 (fix wrong code: for x, in ...)
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# Python 2.5b3: 62111 (fix wrong code: x += yield)
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# Python 2.5c1: 62121 (fix wrong lnotab with for loops and
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# storing constants that should have been removed)
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# Python 2.5c2: 62131 (fix wrong code: for x, in ... in listcomp/genexp)
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# Python 2.6a0: 62151 (peephole optimizations and STORE_MAP opcode)
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# Python 2.6a1: 62161 (WITH_CLEANUP optimization)
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# Python 2.7a0: 62171 (optimize list comprehensions/change LIST_APPEND)
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# Python 2.7a0: 62181 (optimize conditional branches:
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# introduce POP_JUMP_IF_FALSE and POP_JUMP_IF_TRUE)
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# Python 2.7a0 62191 (introduce SETUP_WITH)
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# Python 2.7a0 62201 (introduce BUILD_SET)
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# Python 2.7a0 62211 (introduce MAP_ADD and SET_ADD)
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# Python 3000: 3000
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# 3010 (removed UNARY_CONVERT)
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# 3020 (added BUILD_SET)
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# 3030 (added keyword-only parameters)
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# 3040 (added signature annotations)
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# 3050 (print becomes a function)
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# 3060 (PEP 3115 metaclass syntax)
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# 3061 (string literals become unicode)
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# 3071 (PEP 3109 raise changes)
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# 3081 (PEP 3137 make __file__ and __name__ unicode)
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# 3091 (kill str8 interning)
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# 3101 (merge from 2.6a0, see 62151)
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# 3103 (__file__ points to source file)
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# Python 3.0a4: 3111 (WITH_CLEANUP optimization).
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# Python 3.0b1: 3131 (lexical exception stacking, including POP_EXCEPT
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#3021)
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# Python 3.1a1: 3141 (optimize list, set and dict comprehensions:
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# change LIST_APPEND and SET_ADD, add MAP_ADD #2183)
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# Python 3.1a1: 3151 (optimize conditional branches:
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# introduce POP_JUMP_IF_FALSE and POP_JUMP_IF_TRUE
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#4715)
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# Python 3.2a1: 3160 (add SETUP_WITH #6101)
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# tag: cpython-32
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# Python 3.2a2: 3170 (add DUP_TOP_TWO, remove DUP_TOPX and ROT_FOUR #9225)
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# tag: cpython-32
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# Python 3.2a3 3180 (add DELETE_DEREF #4617)
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# Python 3.3a1 3190 (__class__ super closure changed)
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# Python 3.3a1 3200 (PEP 3155 __qualname__ added #13448)
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# Python 3.3a1 3210 (added size modulo 2**32 to the pyc header #13645)
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# Python 3.3a2 3220 (changed PEP 380 implementation #14230)
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# Python 3.3a4 3230 (revert changes to implicit __class__ closure #14857)
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# Python 3.4a1 3250 (evaluate positional default arguments before
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# keyword-only defaults #16967)
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# Python 3.4a1 3260 (add LOAD_CLASSDEREF; allow locals of class to override
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# free vars #17853)
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# Python 3.4a1 3270 (various tweaks to the __class__ closure #12370)
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# Python 3.4a1 3280 (remove implicit class argument)
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# Python 3.4a4 3290 (changes to __qualname__ computation #19301)
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# Python 3.4a4 3300 (more changes to __qualname__ computation #19301)
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# Python 3.4rc2 3310 (alter __qualname__ computation #20625)
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# Python 3.5a1 3320 (PEP 465: Matrix multiplication operator #21176)
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# Python 3.5b1 3330 (PEP 448: Additional Unpacking Generalizations #2292)
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# Python 3.5b2 3340 (fix dictionary display evaluation order #11205)
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# Python 3.5b3 3350 (add GET_YIELD_FROM_ITER opcode #24400)
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# Python 3.5.2 3351 (fix BUILD_MAP_UNPACK_WITH_CALL opcode #27286)
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# Python 3.6a0 3360 (add FORMAT_VALUE opcode #25483)
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# Python 3.6a1 3361 (lineno delta of code.co_lnotab becomes signed #26107)
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# Python 3.6a2 3370 (16 bit wordcode #26647)
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# Python 3.6a2 3371 (add BUILD_CONST_KEY_MAP opcode #27140)
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# Python 3.6a2 3372 (MAKE_FUNCTION simplification, remove MAKE_CLOSURE
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# #27095)
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# Python 3.6b1 3373 (add BUILD_STRING opcode #27078)
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# Python 3.6b1 3375 (add SETUP_ANNOTATIONS and STORE_ANNOTATION opcodes
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# #27985)
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# Python 3.6b1 3376 (simplify CALL_FUNCTIONs & BUILD_MAP_UNPACK_WITH_CALL
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#27213)
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# Python 3.6b1 3377 (set __class__ cell from type.__new__ #23722)
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# Python 3.6b2 3378 (add BUILD_TUPLE_UNPACK_WITH_CALL #28257)
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# Python 3.6rc1 3379 (more thorough __class__ validation #23722)
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# Python 3.7a1 3390 (add LOAD_METHOD and CALL_METHOD opcodes #26110)
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# Python 3.7a2 3391 (update GET_AITER #31709)
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# Python 3.7a4 3392 (PEP 552: Deterministic pycs #31650)
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# Python 3.7b1 3393 (remove STORE_ANNOTATION opcode #32550)
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# Python 3.7b5 3394 (restored docstring as the first stmt in the body;
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# this might affected the first line number #32911)
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# Python 3.8a1 3400 (move frame block handling to compiler #17611)
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# Python 3.8a1 3401 (add END_ASYNC_FOR #33041)
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# Python 3.8a1 3410 (PEP570 Python Positional-Only Parameters #36540)
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# Python 3.8b2 3411 (Reverse evaluation order of key: value in dict
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# comprehensions #35224)
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# Python 3.8b2 3412 (Swap the position of positional args and positional
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# only args in ast.arguments #37593)
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# Python 3.8b4 3413 (Fix "break" and "continue" in "finally" #37830)
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# Python 3.9a0 3420 (add LOAD_ASSERTION_ERROR #34880)
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# Python 3.9a0 3421 (simplified bytecode for with blocks #32949)
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# Python 3.9a0 3422 (remove BEGIN_FINALLY, END_FINALLY, CALL_FINALLY, POP_FINALLY bytecodes #33387)
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# Python 3.9a2 3423 (add IS_OP, CONTAINS_OP and JUMP_IF_NOT_EXC_MATCH bytecodes #39156)
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# Python 3.9a2 3424 (simplify bytecodes for *value unpacking)
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# Python 3.9a2 3425 (simplify bytecodes for **value unpacking)
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#
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# MAGIC must change whenever the bytecode emitted by the compiler may no
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# longer be understood by older implementations of the eval loop (usually
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# due to the addition of new opcodes).
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#
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# Whenever MAGIC_NUMBER is changed, the ranges in the magic_values array
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# in PC/launcher.c must also be updated.
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MAGIC_NUMBER = (3425).to_bytes(2, 'little') + b'\r\n'
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_RAW_MAGIC_NUMBER = int.from_bytes(MAGIC_NUMBER, 'little') # For import.c
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_PYCACHE = '__pycache__'
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_OPT = 'opt-'
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SOURCE_SUFFIXES = ['.py'] # _setup() adds .pyw as needed.
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BYTECODE_SUFFIXES = ['.pyc']
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# Deprecated.
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DEBUG_BYTECODE_SUFFIXES = OPTIMIZED_BYTECODE_SUFFIXES = BYTECODE_SUFFIXES
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def cache_from_source(path, debug_override=None, *, optimization=None):
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"""Given the path to a .py file, return the path to its .pyc file.
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The .py file does not need to exist; this simply returns the path to the
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.pyc file calculated as if the .py file were imported.
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The 'optimization' parameter controls the presumed optimization level of
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the bytecode file. If 'optimization' is not None, the string representation
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of the argument is taken and verified to be alphanumeric (else ValueError
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is raised).
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The debug_override parameter is deprecated. If debug_override is not None,
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a True value is the same as setting 'optimization' to the empty string
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while a False value is equivalent to setting 'optimization' to '1'.
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If sys.implementation.cache_tag is None then NotImplementedError is raised.
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"""
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if debug_override is not None:
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_warnings.warn('the debug_override parameter is deprecated; use '
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"'optimization' instead", DeprecationWarning)
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if optimization is not None:
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message = 'debug_override or optimization must be set to None'
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raise TypeError(message)
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optimization = '' if debug_override else 1
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path = _os.fspath(path)
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head, tail = _path_split(path)
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base, sep, rest = tail.rpartition('.')
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tag = sys.implementation.cache_tag
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if tag is None:
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raise NotImplementedError('sys.implementation.cache_tag is None')
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almost_filename = ''.join([(base if base else rest), sep, tag])
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if optimization is None:
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if sys.flags.optimize == 0:
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optimization = ''
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else:
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optimization = sys.flags.optimize
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optimization = str(optimization)
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if optimization != '':
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if not optimization.isalnum():
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raise ValueError('{!r} is not alphanumeric'.format(optimization))
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almost_filename = '{}.{}{}'.format(almost_filename, _OPT, optimization)
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filename = almost_filename + BYTECODE_SUFFIXES[0]
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if sys.pycache_prefix is not None:
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# We need an absolute path to the py file to avoid the possibility of
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# collisions within sys.pycache_prefix, if someone has two different
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# `foo/bar.py` on their system and they import both of them using the
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# same sys.pycache_prefix. Let's say sys.pycache_prefix is
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# `C:\Bytecode`; the idea here is that if we get `Foo\Bar`, we first
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# make it absolute (`C:\Somewhere\Foo\Bar`), then make it root-relative
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# (`Somewhere\Foo\Bar`), so we end up placing the bytecode file in an
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# unambiguous `C:\Bytecode\Somewhere\Foo\Bar\`.
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if not _path_isabs(head):
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head = _path_join(_os.getcwd(), head)
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# Strip initial drive from a Windows path. We know we have an absolute
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# path here, so the second part of the check rules out a POSIX path that
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# happens to contain a colon at the second character.
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if head[1] == ':' and head[0] not in path_separators:
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head = head[2:]
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# Strip initial path separator from `head` to complete the conversion
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# back to a root-relative path before joining.
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return _path_join(
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sys.pycache_prefix,
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head.lstrip(path_separators),
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filename,
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)
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return _path_join(head, _PYCACHE, filename)
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def source_from_cache(path):
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"""Given the path to a .pyc. file, return the path to its .py file.
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The .pyc file does not need to exist; this simply returns the path to
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the .py file calculated to correspond to the .pyc file. If path does
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not conform to PEP 3147/488 format, ValueError will be raised. If
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sys.implementation.cache_tag is None then NotImplementedError is raised.
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"""
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if sys.implementation.cache_tag is None:
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raise NotImplementedError('sys.implementation.cache_tag is None')
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path = _os.fspath(path)
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head, pycache_filename = _path_split(path)
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found_in_pycache_prefix = False
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if sys.pycache_prefix is not None:
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stripped_path = sys.pycache_prefix.rstrip(path_separators)
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if head.startswith(stripped_path + path_sep):
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head = head[len(stripped_path):]
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found_in_pycache_prefix = True
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if not found_in_pycache_prefix:
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head, pycache = _path_split(head)
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if pycache != _PYCACHE:
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raise ValueError(f'{_PYCACHE} not bottom-level directory in '
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f'{path!r}')
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dot_count = pycache_filename.count('.')
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if dot_count not in {2, 3}:
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raise ValueError(f'expected only 2 or 3 dots in {pycache_filename!r}')
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elif dot_count == 3:
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optimization = pycache_filename.rsplit('.', 2)[-2]
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if not optimization.startswith(_OPT):
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raise ValueError("optimization portion of filename does not start "
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f"with {_OPT!r}")
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opt_level = optimization[len(_OPT):]
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if not opt_level.isalnum():
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raise ValueError(f"optimization level {optimization!r} is not an "
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"alphanumeric value")
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base_filename = pycache_filename.partition('.')[0]
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return _path_join(head, base_filename + SOURCE_SUFFIXES[0])
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def _get_sourcefile(bytecode_path):
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"""Convert a bytecode file path to a source path (if possible).
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|
|
This function exists purely for backwards-compatibility for
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PyImport_ExecCodeModuleWithFilenames() in the C API.
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"""
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if len(bytecode_path) == 0:
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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()
|
|
|
|
@_check_name
|
|
def get_resource_reader(self, module):
|
|
from importlib.readers import FileReader
|
|
return FileReader(self)
|
|
|
|
|
|
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)
|