Python code coverage for Lib/encodings/init.py

#	count	content
1	n/a	""" Standard "encodings" Package
2	n/a
3	n/a	Standard Python encoding modules are stored in this package
4	n/a	directory.
5	n/a
6	n/a	Codec modules must have names corresponding to normalized encoding
7	n/a	names as defined in the normalize_encoding() function below, e.g.
8	n/a	'utf-8' must be implemented by the module 'utf_8.py'.
9	n/a
10	n/a	Each codec module must export the following interface:
11	n/a
12	n/a	* getregentry() -> codecs.CodecInfo object
13	n/a	The getregentry() API must return a CodecInfo object with encoder, decoder,
14	n/a	incrementalencoder, incrementaldecoder, streamwriter and streamreader
15	n/a	atttributes which adhere to the Python Codec Interface Standard.
16	n/a
17	n/a	In addition, a module may optionally also define the following
18	n/a	APIs which are then used by the package's codec search function:
19	n/a
20	n/a	* getaliases() -> sequence of encoding name strings to use as aliases
21	n/a
22	n/a	Alias names returned by getaliases() must be normalized encoding
23	n/a	names as defined by normalize_encoding().
24	n/a
25	n/a	Written by Marc-Andre Lemburg (mal@lemburg.com).
26	n/a
27	n/a	(c) Copyright CNRI, All Rights Reserved. NO WARRANTY.
28	n/a
29	n/a	"""#"
30	n/a
31	n/a	import codecs
32	n/a	import sys
33	n/a	from . import aliases
34	n/a
35	n/a	_cache = {}
36	n/a	_unknown = '--unknown--'
37	n/a	_import_tail = ['*']
38	n/a	_aliases = aliases.aliases
39	n/a
40	n/a	class CodecRegistryError(LookupError, SystemError):
41	n/a	pass
42	n/a
43	n/a	def normalize_encoding(encoding):
44	n/a
45	n/a	""" Normalize an encoding name.
46	n/a
47	n/a	Normalization works as follows: all non-alphanumeric
48	n/a	characters except the dot used for Python package names are
49	n/a	collapsed and replaced with a single underscore, e.g. ' -;#'
50	n/a	becomes '_'. Leading and trailing underscores are removed.
51	n/a
52	n/a	Note that encoding names should be ASCII only; if they do use
53	n/a	non-ASCII characters, these must be Latin-1 compatible.
54	n/a
55	n/a	"""
56	n/a	if isinstance(encoding, bytes):
57	n/a	encoding = str(encoding, "ascii")
58	n/a
59	n/a	chars = []
60	n/a	punct = False
61	n/a	for c in encoding:
62	n/a	if c.isalnum() or c == '.':
63	n/a	if punct and chars:
64	n/a	chars.append('_')
65	n/a	chars.append(c)
66	n/a	punct = False
67	n/a	else:
68	n/a	punct = True
69	n/a	return ''.join(chars)
70	n/a
71	n/a	def search_function(encoding):
72	n/a
73	n/a	# Cache lookup
74	n/a	entry = _cache.get(encoding, _unknown)
75	n/a	if entry is not _unknown:
76	n/a	return entry
77	n/a
78	n/a	# Import the module:
79	n/a	#
80	n/a	# First try to find an alias for the normalized encoding
81	n/a	# name and lookup the module using the aliased name, then try to
82	n/a	# lookup the module using the standard import scheme, i.e. first
83	n/a	# try in the encodings package, then at top-level.
84	n/a	#
85	n/a	norm_encoding = normalize_encoding(encoding)
86	n/a	aliased_encoding = _aliases.get(norm_encoding) or \
87	n/a	_aliases.get(norm_encoding.replace('.', '_'))
88	n/a	if aliased_encoding is not None:
89	n/a	modnames = [aliased_encoding,
90	n/a	norm_encoding]
91	n/a	else:
92	n/a	modnames = [norm_encoding]
93	n/a	for modname in modnames:
94	n/a	if not modname or '.' in modname:
95	n/a	continue
96	n/a	try:
97	n/a	# Import is absolute to prevent the possibly malicious import of a
98	n/a	# module with side-effects that is not in the 'encodings' package.
99	n/a	mod = __import__('encodings.' + modname, fromlist=_import_tail,
100	n/a	level=0)
101	n/a	except ImportError:
102	n/a	# ImportError may occur because 'encodings.(modname)' does not exist,
103	n/a	# or because it imports a name that does not exist (see mbcs and oem)
104	n/a	pass
105	n/a	else:
106	n/a	break
107	n/a	else:
108	n/a	mod = None
109	n/a
110	n/a	try:
111	n/a	getregentry = mod.getregentry
112	n/a	except AttributeError:
113	n/a	# Not a codec module
114	n/a	mod = None
115	n/a
116	n/a	if mod is None:
117	n/a	# Cache misses
118	n/a	_cache[encoding] = None
119	n/a	return None
120	n/a
121	n/a	# Now ask the module for the registry entry
122	n/a	entry = getregentry()
123	n/a	if not isinstance(entry, codecs.CodecInfo):
124	n/a	if not 4 <= len(entry) <= 7:
125	n/a	raise CodecRegistryError('module "%s" (%s) failed to register'
126	n/a	% (mod.__name__, mod.__file__))
127	n/a	if not callable(entry[0]) or not callable(entry[1]) or \
128	n/a	(entry[2] is not None and not callable(entry[2])) or \
129	n/a	(entry[3] is not None and not callable(entry[3])) or \
130	n/a	(len(entry) > 4 and entry[4] is not None and not callable(entry[4])) or \
131	n/a	(len(entry) > 5 and entry[5] is not None and not callable(entry[5])):
132	n/a	raise CodecRegistryError('incompatible codecs in module "%s" (%s)'
133	n/a	% (mod.__name__, mod.__file__))
134	n/a	if len(entry)<7 or entry[6] is None:
135	n/a	entry += (None,)*(6-len(entry)) + (mod.__name__.split(".", 1)[1],)
136	n/a	entry = codecs.CodecInfo(*entry)
137	n/a
138	n/a	# Cache the codec registry entry
139	n/a	_cache[encoding] = entry
140	n/a
141	n/a	# Register its aliases (without overwriting previously registered
142	n/a	# aliases)
143	n/a	try:
144	n/a	codecaliases = mod.getaliases()
145	n/a	except AttributeError:
146	n/a	pass
147	n/a	else:
148	n/a	for alias in codecaliases:
149	n/a	if alias not in _aliases:
150	n/a	_aliases[alias] = modname
151	n/a
152	n/a	# Return the registry entry
153	n/a	return entry
154	n/a
155	n/a	# Register the search_function in the Python codec registry
156	n/a	codecs.register(search_function)
157	n/a
158	n/a	if sys.platform == 'win32':
159	n/a	def _alias_mbcs(encoding):
160	n/a	try:
161	n/a	import _bootlocale
162	n/a	if encoding == _bootlocale.getpreferredencoding(False):
163	n/a	import encodings.mbcs
164	n/a	return encodings.mbcs.getregentry()
165	n/a	except ImportError:
166	n/a	# Imports may fail while we are shutting down
167	n/a	pass
168	n/a
169	n/a	codecs.register(_alias_mbcs)

Python code coverage for Lib/encodings/__init__.py

Python code coverage for Lib/encodings/init.py