This file is indexed.

/usr/lib/python3/dist-packages/jinja2/debug.py is in python3-jinja2 2.8-1.

This file is owned by root:root, with mode 0o644.

The actual contents of the file can be viewed below.

  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
# -*- coding: utf-8 -*-
"""
    jinja2.debug
    ~~~~~~~~~~~~

    Implements the debug interface for Jinja.  This module does some pretty
    ugly stuff with the Python traceback system in order to achieve tracebacks
    with correct line numbers, locals and contents.

    :copyright: (c) 2010 by the Jinja Team.
    :license: BSD, see LICENSE for more details.
"""
import sys
import traceback
from types import TracebackType, CodeType
from jinja2.utils import missing, internal_code
from jinja2.exceptions import TemplateSyntaxError
from jinja2._compat import iteritems, reraise, PY2

# on pypy we can take advantage of transparent proxies
try:
    from __pypy__ import tproxy
except ImportError:
    tproxy = None


# how does the raise helper look like?
try:
    exec("raise TypeError, 'foo'")
except SyntaxError:
    raise_helper = 'raise __jinja_exception__[1]'
except TypeError:
    raise_helper = 'raise __jinja_exception__[0], __jinja_exception__[1]'


class TracebackFrameProxy(object):
    """Proxies a traceback frame."""

    def __init__(self, tb):
        self.tb = tb
        self._tb_next = None

    @property
    def tb_next(self):
        return self._tb_next

    def set_next(self, next):
        if tb_set_next is not None:
            try:
                tb_set_next(self.tb, next and next.tb or None)
            except Exception:
                # this function can fail due to all the hackery it does
                # on various python implementations.  We just catch errors
                # down and ignore them if necessary.
                pass
        self._tb_next = next

    @property
    def is_jinja_frame(self):
        return '__jinja_template__' in self.tb.tb_frame.f_globals

    def __getattr__(self, name):
        return getattr(self.tb, name)


def make_frame_proxy(frame):
    proxy = TracebackFrameProxy(frame)
    if tproxy is None:
        return proxy
    def operation_handler(operation, *args, **kwargs):
        if operation in ('__getattribute__', '__getattr__'):
            return getattr(proxy, args[0])
        elif operation == '__setattr__':
            proxy.__setattr__(*args, **kwargs)
        else:
            return getattr(proxy, operation)(*args, **kwargs)
    return tproxy(TracebackType, operation_handler)


class ProcessedTraceback(object):
    """Holds a Jinja preprocessed traceback for printing or reraising."""

    def __init__(self, exc_type, exc_value, frames):
        assert frames, 'no frames for this traceback?'
        self.exc_type = exc_type
        self.exc_value = exc_value
        self.frames = frames

        # newly concatenate the frames (which are proxies)
        prev_tb = None
        for tb in self.frames:
            if prev_tb is not None:
                prev_tb.set_next(tb)
            prev_tb = tb
        prev_tb.set_next(None)

    def render_as_text(self, limit=None):
        """Return a string with the traceback."""
        lines = traceback.format_exception(self.exc_type, self.exc_value,
                                           self.frames[0], limit=limit)
        return ''.join(lines).rstrip()

    def render_as_html(self, full=False):
        """Return a unicode string with the traceback as rendered HTML."""
        from jinja2.debugrenderer import render_traceback
        return u'%s\n\n<!--\n%s\n-->' % (
            render_traceback(self, full=full),
            self.render_as_text().decode('utf-8', 'replace')
        )

    @property
    def is_template_syntax_error(self):
        """`True` if this is a template syntax error."""
        return isinstance(self.exc_value, TemplateSyntaxError)

    @property
    def exc_info(self):
        """Exception info tuple with a proxy around the frame objects."""
        return self.exc_type, self.exc_value, self.frames[0]

    @property
    def standard_exc_info(self):
        """Standard python exc_info for re-raising"""
        tb = self.frames[0]
        # the frame will be an actual traceback (or transparent proxy) if
        # we are on pypy or a python implementation with support for tproxy
        if type(tb) is not TracebackType:
            tb = tb.tb
        return self.exc_type, self.exc_value, tb


def make_traceback(exc_info, source_hint=None):
    """Creates a processed traceback object from the exc_info."""
    exc_type, exc_value, tb = exc_info
    if isinstance(exc_value, TemplateSyntaxError):
        exc_info = translate_syntax_error(exc_value, source_hint)
        initial_skip = 0
    else:
        initial_skip = 1
    return translate_exception(exc_info, initial_skip)


def translate_syntax_error(error, source=None):
    """Rewrites a syntax error to please traceback systems."""
    error.source = source
    error.translated = True
    exc_info = (error.__class__, error, None)
    filename = error.filename
    if filename is None:
        filename = '<unknown>'
    return fake_exc_info(exc_info, filename, error.lineno)


def translate_exception(exc_info, initial_skip=0):
    """If passed an exc_info it will automatically rewrite the exceptions
    all the way down to the correct line numbers and frames.
    """
    tb = exc_info[2]
    frames = []

    # skip some internal frames if wanted
    for x in range(initial_skip):
        if tb is not None:
            tb = tb.tb_next
    initial_tb = tb

    while tb is not None:
        # skip frames decorated with @internalcode.  These are internal
        # calls we can't avoid and that are useless in template debugging
        # output.
        if tb.tb_frame.f_code in internal_code:
            tb = tb.tb_next
            continue

        # save a reference to the next frame if we override the current
        # one with a faked one.
        next = tb.tb_next

        # fake template exceptions
        template = tb.tb_frame.f_globals.get('__jinja_template__')
        if template is not None:
            lineno = template.get_corresponding_lineno(tb.tb_lineno)
            tb = fake_exc_info(exc_info[:2] + (tb,), template.filename,
                               lineno)[2]

        frames.append(make_frame_proxy(tb))
        tb = next

    # if we don't have any exceptions in the frames left, we have to
    # reraise it unchanged.
    # XXX: can we backup here?  when could this happen?
    if not frames:
        reraise(exc_info[0], exc_info[1], exc_info[2])

    return ProcessedTraceback(exc_info[0], exc_info[1], frames)


def fake_exc_info(exc_info, filename, lineno):
    """Helper for `translate_exception`."""
    exc_type, exc_value, tb = exc_info

    # figure the real context out
    if tb is not None:
        real_locals = tb.tb_frame.f_locals.copy()
        ctx = real_locals.get('context')
        if ctx:
            locals = ctx.get_all()
        else:
            locals = {}
        for name, value in iteritems(real_locals):
            if name.startswith('l_') and value is not missing:
                locals[name[2:]] = value

        # if there is a local called __jinja_exception__, we get
        # rid of it to not break the debug functionality.
        locals.pop('__jinja_exception__', None)
    else:
        locals = {}

    # assamble fake globals we need
    globals = {
        '__name__':             filename,
        '__file__':             filename,
        '__jinja_exception__':  exc_info[:2],

        # we don't want to keep the reference to the template around
        # to not cause circular dependencies, but we mark it as Jinja
        # frame for the ProcessedTraceback
        '__jinja_template__':   None
    }

    # and fake the exception
    code = compile('\n' * (lineno - 1) + raise_helper, filename, 'exec')

    # if it's possible, change the name of the code.  This won't work
    # on some python environments such as google appengine
    try:
        if tb is None:
            location = 'template'
        else:
            function = tb.tb_frame.f_code.co_name
            if function == 'root':
                location = 'top-level template code'
            elif function.startswith('block_'):
                location = 'block "%s"' % function[6:]
            else:
                location = 'template'

        if PY2:
            code = CodeType(0, code.co_nlocals, code.co_stacksize,
                            code.co_flags, code.co_code, code.co_consts,
                            code.co_names, code.co_varnames, filename,
                            location, code.co_firstlineno,
                            code.co_lnotab, (), ())
        else:
            code = CodeType(0, code.co_kwonlyargcount,
                            code.co_nlocals, code.co_stacksize,
                            code.co_flags, code.co_code, code.co_consts,
                            code.co_names, code.co_varnames, filename,
                            location, code.co_firstlineno,
                            code.co_lnotab, (), ())
    except Exception as e:
        pass

    # execute the code and catch the new traceback
    try:
        exec(code, globals, locals)
    except:
        exc_info = sys.exc_info()
        new_tb = exc_info[2].tb_next

    # return without this frame
    return exc_info[:2] + (new_tb,)


def _init_ugly_crap():
    """This function implements a few ugly things so that we can patch the
    traceback objects.  The function returned allows resetting `tb_next` on
    any python traceback object.  Do not attempt to use this on non cpython
    interpreters
    """
    import ctypes
    from types import TracebackType

    if PY2:
        # figure out size of _Py_ssize_t for Python 2:
        if hasattr(ctypes.pythonapi, 'Py_InitModule4_64'):
            _Py_ssize_t = ctypes.c_int64
        else:
            _Py_ssize_t = ctypes.c_int
    else:
        # platform ssize_t on Python 3
        _Py_ssize_t = ctypes.c_ssize_t

    # regular python
    class _PyObject(ctypes.Structure):
        pass
    _PyObject._fields_ = [
        ('ob_refcnt', _Py_ssize_t),
        ('ob_type', ctypes.POINTER(_PyObject))
    ]

    # python with trace
    if hasattr(sys, 'getobjects'):
        class _PyObject(ctypes.Structure):
            pass
        _PyObject._fields_ = [
            ('_ob_next', ctypes.POINTER(_PyObject)),
            ('_ob_prev', ctypes.POINTER(_PyObject)),
            ('ob_refcnt', _Py_ssize_t),
            ('ob_type', ctypes.POINTER(_PyObject))
        ]

    class _Traceback(_PyObject):
        pass
    _Traceback._fields_ = [
        ('tb_next', ctypes.POINTER(_Traceback)),
        ('tb_frame', ctypes.POINTER(_PyObject)),
        ('tb_lasti', ctypes.c_int),
        ('tb_lineno', ctypes.c_int)
    ]

    def tb_set_next(tb, next):
        """Set the tb_next attribute of a traceback object."""
        if not (isinstance(tb, TracebackType) and
                (next is None or isinstance(next, TracebackType))):
            raise TypeError('tb_set_next arguments must be traceback objects')
        obj = _Traceback.from_address(id(tb))
        if tb.tb_next is not None:
            old = _Traceback.from_address(id(tb.tb_next))
            old.ob_refcnt -= 1
        if next is None:
            obj.tb_next = ctypes.POINTER(_Traceback)()
        else:
            next = _Traceback.from_address(id(next))
            next.ob_refcnt += 1
            obj.tb_next = ctypes.pointer(next)

    return tb_set_next


# try to get a tb_set_next implementation if we don't have transparent
# proxies.
tb_set_next = None
if tproxy is None:
    try:
        tb_set_next = _init_ugly_crap()
    except:
        pass
    del _init_ugly_crap