1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
|
# encoding.py - character transcoding support for Mercurial
#
# Copyright 2005-2009 Matt Mackall <mpm@selenic.com> and others
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.
import error
import unicodedata, locale, os
def _getpreferredencoding():
'''
On darwin, getpreferredencoding ignores the locale environment and
always returns mac-roman. http://bugs.python.org/issue6202 fixes this
for Python 2.7 and up. This is the same corrected code for earlier
Python versions.
However, we can't use a version check for this method, as some distributions
patch Python to fix this. Instead, we use it as a 'fixer' for the mac-roman
encoding, as it is unlikely that this encoding is the actually expected.
'''
try:
locale.CODESET
except AttributeError:
# Fall back to parsing environment variables :-(
return locale.getdefaultlocale()[1]
oldloc = locale.setlocale(locale.LC_CTYPE)
locale.setlocale(locale.LC_CTYPE, "")
result = locale.nl_langinfo(locale.CODESET)
locale.setlocale(locale.LC_CTYPE, oldloc)
return result
_encodingfixers = {
'646': lambda: 'ascii',
'ANSI_X3.4-1968': lambda: 'ascii',
'mac-roman': _getpreferredencoding
}
try:
encoding = os.environ.get("HGENCODING")
if not encoding:
encoding = locale.getpreferredencoding() or 'ascii'
encoding = _encodingfixers.get(encoding, lambda: encoding)()
except locale.Error:
encoding = 'ascii'
encodingmode = os.environ.get("HGENCODINGMODE", "strict")
fallbackencoding = 'ISO-8859-1'
class localstr(str):
'''This class allows strings that are unmodified to be
round-tripped to the local encoding and back'''
def __new__(cls, u, l):
s = str.__new__(cls, l)
s._utf8 = u
return s
def __hash__(self):
return hash(self._utf8) # avoid collisions in local string space
def tolocal(s):
"""
Convert a string from internal UTF-8 to local encoding
All internal strings should be UTF-8 but some repos before the
implementation of locale support may contain latin1 or possibly
other character sets. We attempt to decode everything strictly
using UTF-8, then Latin-1, and failing that, we use UTF-8 and
replace unknown characters.
The localstr class is used to cache the known UTF-8 encoding of
strings next to their local representation to allow lossless
round-trip conversion back to UTF-8.
>>> u = 'foo: \\xc3\\xa4' # utf-8
>>> l = tolocal(u)
>>> l
'foo: ?'
>>> fromlocal(l)
'foo: \\xc3\\xa4'
>>> u2 = 'foo: \\xc3\\xa1'
>>> d = { l: 1, tolocal(u2): 2 }
>>> d # no collision
{'foo: ?': 1, 'foo: ?': 2}
>>> 'foo: ?' in d
False
>>> l1 = 'foo: \\xe4' # historical latin1 fallback
>>> l = tolocal(l1)
>>> l
'foo: ?'
>>> fromlocal(l) # magically in utf-8
'foo: \\xc3\\xa4'
"""
try:
try:
# make sure string is actually stored in UTF-8
u = s.decode('UTF-8')
if encoding == 'UTF-8':
# fast path
return s
r = u.encode(encoding, "replace")
if u == r.decode(encoding):
# r is a safe, non-lossy encoding of s
return r
return localstr(s, r)
except UnicodeDecodeError:
# we should only get here if we're looking at an ancient changeset
try:
u = s.decode(fallbackencoding)
r = u.encode(encoding, "replace")
if u == r.decode(encoding):
# r is a safe, non-lossy encoding of s
return r
return localstr(u.encode('UTF-8'), r)
except UnicodeDecodeError:
u = s.decode("utf-8", "replace") # last ditch
return u.encode(encoding, "replace") # can't round-trip
except LookupError, k:
raise error.Abort(k, hint="please check your locale settings")
def fromlocal(s):
"""
Convert a string from the local character encoding to UTF-8
We attempt to decode strings using the encoding mode set by
HGENCODINGMODE, which defaults to 'strict'. In this mode, unknown
characters will cause an error message. Other modes include
'replace', which replaces unknown characters with a special
Unicode character, and 'ignore', which drops the character.
"""
# can we do a lossless round-trip?
if isinstance(s, localstr):
return s._utf8
try:
return s.decode(encoding, encodingmode).encode("utf-8")
except UnicodeDecodeError, inst:
sub = s[max(0, inst.start - 10):inst.start + 10]
raise error.Abort("decoding near '%s': %s!" % (sub, inst))
except LookupError, k:
raise error.Abort(k, hint="please check your locale settings")
# How to treat ambiguous-width characters. Set to 'wide' to treat as wide.
wide = (os.environ.get("HGENCODINGAMBIGUOUS", "narrow") == "wide"
and "WFA" or "WF")
def colwidth(s):
"Find the column width of a string for display in the local encoding"
return ucolwidth(s.decode(encoding, 'replace'))
def ucolwidth(d):
"Find the column width of a Unicode string for display"
eaw = getattr(unicodedata, 'east_asian_width', None)
if eaw is not None:
return sum([eaw(c) in wide and 2 or 1 for c in d])
return len(d)
def getcols(s, start, c):
'''Use colwidth to find a c-column substring of s starting at byte
index start'''
for x in xrange(start + c, len(s)):
t = s[start:x]
if colwidth(t) == c:
return t
def lower(s):
"best-effort encoding-aware case-folding of local string s"
try:
s.decode('ascii') # throw exception for non-ASCII character
return s.lower()
except UnicodeDecodeError:
pass
try:
if isinstance(s, localstr):
u = s._utf8.decode("utf-8")
else:
u = s.decode(encoding, encodingmode)
lu = u.lower()
if u == lu:
return s # preserve localstring
return lu.encode(encoding)
except UnicodeError:
return s.lower() # we don't know how to fold this except in ASCII
except LookupError, k:
raise error.Abort(k, hint="please check your locale settings")
def upper(s):
"best-effort encoding-aware case-folding of local string s"
try:
s.decode('ascii') # throw exception for non-ASCII character
return s.upper()
except UnicodeDecodeError:
pass
try:
if isinstance(s, localstr):
u = s._utf8.decode("utf-8")
else:
u = s.decode(encoding, encodingmode)
uu = u.upper()
if u == uu:
return s # preserve localstring
return uu.encode(encoding)
except UnicodeError:
return s.upper() # we don't know how to fold this except in ASCII
except LookupError, k:
raise error.Abort(k, hint="please check your locale settings")
def toutf8b(s):
'''convert a local, possibly-binary string into UTF-8b
This is intended as a generic method to preserve data when working
with schemes like JSON and XML that have no provision for
arbitrary byte strings. As Mercurial often doesn't know
what encoding data is in, we use so-called UTF-8b.
If a string is already valid UTF-8 (or ASCII), it passes unmodified.
Otherwise, unsupported bytes are mapped to UTF-16 surrogate range,
uDC00-uDCFF.
Principles of operation:
- ASCII and UTF-8 data sucessfully round-trips and is understood
by Unicode-oriented clients
- filenames and file contents in arbitrary other encodings can have
be round-tripped or recovered by clueful clients
- local strings that have a cached known UTF-8 encoding (aka
localstr) get sent as UTF-8 so Unicode-oriented clients get the
Unicode data they want
- because we must preserve UTF-8 bytestring in places such as
filenames, metadata can't be roundtripped without help
(Note: "UTF-8b" often refers to decoding a mix of valid UTF-8 and
arbitrary bytes into an internal Unicode format that can be
re-encoded back into the original. Here we are exposing the
internal surrogate encoding as a UTF-8 string.)
'''
if isinstance(s, localstr):
return s._utf8
try:
if s.decode('utf-8'):
return s
except UnicodeDecodeError:
# surrogate-encode any characters that don't round-trip
s2 = s.decode('utf-8', 'ignore').encode('utf-8')
r = ""
pos = 0
for c in s:
if s2[pos:pos + 1] == c:
r += c
pos += 1
else:
r += unichr(0xdc00 + ord(c)).encode('utf-8')
return r
def fromutf8b(s):
'''Given a UTF-8b string, return a local, possibly-binary string.
return the original binary string. This
is a round-trip process for strings like filenames, but metadata
that's was passed through tolocal will remain in UTF-8.
>>> m = "\\xc3\\xa9\\x99abcd"
>>> n = toutf8b(m)
>>> n
'\\xc3\\xa9\\xed\\xb2\\x99abcd'
>>> fromutf8b(n) == m
True
'''
# fast path - look for uDxxx prefixes in s
if "\xed" not in s:
return s
u = s.decode("utf-8")
r = ""
for c in u:
if ord(c) & 0xff00 == 0xdc00:
r += chr(ord(c) & 0xff)
else:
r += c.encode("utf-8")
return r
|