From c50b8e7fb9b2e61d4d195a055cd1bbf993cc455f Mon Sep 17 00:00:00 2001 From: Christophe Vu-Brugier Date: Wed, 22 Feb 2017 16:48:49 -0800 Subject: [PATCH] Add importlib fix for PEP 3147 issue Python 3 has a new standard for installing .pyc file, called PEP 3147. Unfortunately, this standard requires both the .py and .pyc files to be installed for a Python module to be found. This is quite annoying on space-constrained embedded systems, since the .py file is technically not required for execution. This patch changes cache_from_source() and source_from_cache() in importlib to get rid of the "__pycache__" directory. This effectively disables PEP 3147 for: * The python standard library * Packages built with distutils or setuptools * Packages built with automake that use the `py-compile` helper Signed-off-by: Christophe Vu-Brugier [ Andrey Smirnov: ported to Python 3.6 ] Signed-off-by: Andrey Smirnov --- Lib/importlib/_bootstrap_external.py | 44 ++++------------------------ 1 file changed, 5 insertions(+), 39 deletions(-) diff --git a/Lib/importlib/_bootstrap_external.py b/Lib/importlib/_bootstrap_external.py index b8ac482994..db034f605a 100644 --- a/Lib/importlib/_bootstrap_external.py +++ b/Lib/importlib/_bootstrap_external.py @@ -306,8 +306,6 @@ def cache_from_source(path, debug_override=None, *, optimization=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 ' @@ -319,10 +317,7 @@ def cache_from_source(path, debug_override=None, *, optimization=None): 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]) + almost_filename = ''.join([(base if base else rest)]) if optimization is None: if sys.flags.optimize == 0: optimization = '' @@ -359,46 +354,17 @@ def cache_from_source(path, debug_override=None, *, optimization=None): head.lstrip(path_separators), filename, ) - return _path_join(head, _PYCACHE, filename) + return _path_join(head, 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. - + the .py file calculated to correspond to the .pyc file. """ - 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] + head, filename = _path_split(path) + base_filename = filename.partition('.')[0] return _path_join(head, base_filename + SOURCE_SUFFIXES[0]) -- 2.20.1