File: util.py

package info (click to toggle)
mako 1.0.6%2Bds1-2
  • links: PTS, VCS
  • area: main
  • in suites: stretch
  • size: 1,556 kB
  • ctags: 1,495
  • sloc: python: 11,807; makefile: 167
file content (382 lines) | stat: -rw-r--r-- 10,927 bytes parent folder | download | duplicates (2)
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
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
# mako/util.py
# Copyright (C) 2006-2016 the Mako authors and contributors <see AUTHORS file>
#
# This module is part of Mako and is released under
# the MIT License: http://www.opensource.org/licenses/mit-license.php

import re
import collections
import codecs
import os
from mako import compat
import operator


def update_wrapper(decorated, fn):
    decorated.__wrapped__ = fn
    decorated.__name__ = fn.__name__
    return decorated


class PluginLoader(object):

    def __init__(self, group):
        self.group = group
        self.impls = {}

    def load(self, name):
        if name in self.impls:
            return self.impls[name]()
        else:
            import pkg_resources
            for impl in pkg_resources.iter_entry_points(
                    self.group,
                    name):
                self.impls[name] = impl.load
                return impl.load()
            else:
                from mako import exceptions
                raise exceptions.RuntimeException(
                    "Can't load plugin %s %s" %
                    (self.group, name))

    def register(self, name, modulepath, objname):
        def load():
            mod = __import__(modulepath)
            for token in modulepath.split(".")[1:]:
                mod = getattr(mod, token)
            return getattr(mod, objname)
        self.impls[name] = load


def verify_directory(dir):
    """create and/or verify a filesystem directory."""

    tries = 0

    while not os.path.exists(dir):
        try:
            tries += 1
            os.makedirs(dir, compat.octal("0775"))
        except:
            if tries > 5:
                raise


def to_list(x, default=None):
    if x is None:
        return default
    if not isinstance(x, (list, tuple)):
        return [x]
    else:
        return x


class memoized_property(object):

    """A read-only @property that is only evaluated once."""

    def __init__(self, fget, doc=None):
        self.fget = fget
        self.__doc__ = doc or fget.__doc__
        self.__name__ = fget.__name__

    def __get__(self, obj, cls):
        if obj is None:
            return self
        obj.__dict__[self.__name__] = result = self.fget(obj)
        return result


class memoized_instancemethod(object):

    """Decorate a method memoize its return value.

    Best applied to no-arg methods: memoization is not sensitive to
    argument values, and will always return the same value even when
    called with different arguments.

    """

    def __init__(self, fget, doc=None):
        self.fget = fget
        self.__doc__ = doc or fget.__doc__
        self.__name__ = fget.__name__

    def __get__(self, obj, cls):
        if obj is None:
            return self

        def oneshot(*args, **kw):
            result = self.fget(obj, *args, **kw)
            memo = lambda *a, **kw: result
            memo.__name__ = self.__name__
            memo.__doc__ = self.__doc__
            obj.__dict__[self.__name__] = memo
            return result
        oneshot.__name__ = self.__name__
        oneshot.__doc__ = self.__doc__
        return oneshot


class SetLikeDict(dict):

    """a dictionary that has some setlike methods on it"""

    def union(self, other):
        """produce a 'union' of this dict and another (at the key level).

        values in the second dict take precedence over that of the first"""
        x = SetLikeDict(**self)
        x.update(other)
        return x


class FastEncodingBuffer(object):

    """a very rudimentary buffer that is faster than StringIO,
    but doesn't crash on unicode data like cStringIO."""

    def __init__(self, encoding=None, errors='strict', as_unicode=False):
        self.data = collections.deque()
        self.encoding = encoding
        if as_unicode:
            self.delim = compat.u('')
        else:
            self.delim = ''
        self.as_unicode = as_unicode
        self.errors = errors
        self.write = self.data.append

    def truncate(self):
        self.data = collections.deque()
        self.write = self.data.append

    def getvalue(self):
        if self.encoding:
            return self.delim.join(self.data).encode(self.encoding,
                                                     self.errors)
        else:
            return self.delim.join(self.data)


class LRUCache(dict):

    """A dictionary-like object that stores a limited number of items,
    discarding lesser used items periodically.

    this is a rewrite of LRUCache from Myghty to use a periodic timestamp-based
    paradigm so that synchronization is not really needed.  the size management
    is inexact.
    """

    class _Item(object):

        def __init__(self, key, value):
            self.key = key
            self.value = value
            self.timestamp = compat.time_func()

        def __repr__(self):
            return repr(self.value)

    def __init__(self, capacity, threshold=.5):
        self.capacity = capacity
        self.threshold = threshold

    def __getitem__(self, key):
        item = dict.__getitem__(self, key)
        item.timestamp = compat.time_func()
        return item.value

    def values(self):
        return [i.value for i in dict.values(self)]

    def setdefault(self, key, value):
        if key in self:
            return self[key]
        else:
            self[key] = value
            return value

    def __setitem__(self, key, value):
        item = dict.get(self, key)
        if item is None:
            item = self._Item(key, value)
            dict.__setitem__(self, key, item)
        else:
            item.value = value
        self._manage_size()

    def _manage_size(self):
        while len(self) > self.capacity + self.capacity * self.threshold:
            bytime = sorted(dict.values(self),
                            key=operator.attrgetter('timestamp'), reverse=True)
            for item in bytime[self.capacity:]:
                try:
                    del self[item.key]
                except KeyError:
                    # if we couldn't find a key, most likely some other thread
                    # broke in on us. loop around and try again
                    break

# Regexp to match python magic encoding line
_PYTHON_MAGIC_COMMENT_re = re.compile(
    r'[ \t\f]* \# .* coding[=:][ \t]*([-\w.]+)',
    re.VERBOSE)


def parse_encoding(fp):
    """Deduce the encoding of a Python source file (binary mode) from magic
    comment.

    It does this in the same way as the `Python interpreter`__

    .. __: http://docs.python.org/ref/encodings.html

    The ``fp`` argument should be a seekable file object in binary mode.
    """
    pos = fp.tell()
    fp.seek(0)
    try:
        line1 = fp.readline()
        has_bom = line1.startswith(codecs.BOM_UTF8)
        if has_bom:
            line1 = line1[len(codecs.BOM_UTF8):]

        m = _PYTHON_MAGIC_COMMENT_re.match(line1.decode('ascii', 'ignore'))
        if not m:
            try:
                import parser
                parser.suite(line1.decode('ascii', 'ignore'))
            except (ImportError, SyntaxError):
                # Either it's a real syntax error, in which case the source
                # is not valid python source, or line2 is a continuation of
                # line1, in which case we don't want to scan line2 for a magic
                # comment.
                pass
            else:
                line2 = fp.readline()
                m = _PYTHON_MAGIC_COMMENT_re.match(
                    line2.decode('ascii', 'ignore'))

        if has_bom:
            if m:
                raise SyntaxError(
                    "python refuses to compile code with both a UTF8"
                    " byte-order-mark and a magic encoding comment")
            return 'utf_8'
        elif m:
            return m.group(1)
        else:
            return None
    finally:
        fp.seek(pos)


def sorted_dict_repr(d):
    """repr() a dictionary with the keys in order.

    Used by the lexer unit test to compare parse trees based on strings.

    """
    keys = list(d.keys())
    keys.sort()
    return "{" + ", ".join(["%r: %r" % (k, d[k]) for k in keys]) + "}"


def restore__ast(_ast):
    """Attempt to restore the required classes to the _ast module if it
    appears to be missing them
    """
    if hasattr(_ast, 'AST'):
        return
    _ast.PyCF_ONLY_AST = 2 << 9
    m = compile("""\
def foo(): pass
class Bar(object): pass
if False: pass
baz = 'mako'
1 + 2 - 3 * 4 / 5
6 // 7 % 8 << 9 >> 10
11 & 12 ^ 13 | 14
15 and 16 or 17
-baz + (not +18) - ~17
baz and 'foo' or 'bar'
(mako is baz == baz) is not baz != mako
mako > baz < mako >= baz <= mako
mako in baz not in mako""", '<unknown>', 'exec', _ast.PyCF_ONLY_AST)
    _ast.Module = type(m)

    for cls in _ast.Module.__mro__:
        if cls.__name__ == 'mod':
            _ast.mod = cls
        elif cls.__name__ == 'AST':
            _ast.AST = cls

    _ast.FunctionDef = type(m.body[0])
    _ast.ClassDef = type(m.body[1])
    _ast.If = type(m.body[2])

    _ast.Name = type(m.body[3].targets[0])
    _ast.Store = type(m.body[3].targets[0].ctx)
    _ast.Str = type(m.body[3].value)

    _ast.Sub = type(m.body[4].value.op)
    _ast.Add = type(m.body[4].value.left.op)
    _ast.Div = type(m.body[4].value.right.op)
    _ast.Mult = type(m.body[4].value.right.left.op)

    _ast.RShift = type(m.body[5].value.op)
    _ast.LShift = type(m.body[5].value.left.op)
    _ast.Mod = type(m.body[5].value.left.left.op)
    _ast.FloorDiv = type(m.body[5].value.left.left.left.op)

    _ast.BitOr = type(m.body[6].value.op)
    _ast.BitXor = type(m.body[6].value.left.op)
    _ast.BitAnd = type(m.body[6].value.left.left.op)

    _ast.Or = type(m.body[7].value.op)
    _ast.And = type(m.body[7].value.values[0].op)

    _ast.Invert = type(m.body[8].value.right.op)
    _ast.Not = type(m.body[8].value.left.right.op)
    _ast.UAdd = type(m.body[8].value.left.right.operand.op)
    _ast.USub = type(m.body[8].value.left.left.op)

    _ast.Or = type(m.body[9].value.op)
    _ast.And = type(m.body[9].value.values[0].op)

    _ast.IsNot = type(m.body[10].value.ops[0])
    _ast.NotEq = type(m.body[10].value.ops[1])
    _ast.Is = type(m.body[10].value.left.ops[0])
    _ast.Eq = type(m.body[10].value.left.ops[1])

    _ast.Gt = type(m.body[11].value.ops[0])
    _ast.Lt = type(m.body[11].value.ops[1])
    _ast.GtE = type(m.body[11].value.ops[2])
    _ast.LtE = type(m.body[11].value.ops[3])

    _ast.In = type(m.body[12].value.ops[0])
    _ast.NotIn = type(m.body[12].value.ops[1])


def read_file(path, mode='rb'):
    fp = open(path, mode)
    try:
        data = fp.read()
        return data
    finally:
        fp.close()


def read_python_file(path):
    fp = open(path, "rb")
    try:
        encoding = parse_encoding(fp)
        data = fp.read()
        if encoding:
            data = data.decode(encoding)
        return data
    finally:
        fp.close()