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				| # -*- coding: utf-8 -*-
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| """
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|     jinja2.debug
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|     ~~~~~~~~~~~~
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| 
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|     Implements the debug interface for Jinja.  This module does some pretty
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|     ugly stuff with the Python traceback system in order to achieve tracebacks
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|     with correct line numbers, locals and contents.
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| 
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|     :copyright: (c) 2017 by the Jinja Team.
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|     :license: BSD, see LICENSE for more details.
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| """
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| import sys
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| import traceback
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| from types import TracebackType, CodeType
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| from jinja2.utils import missing, internal_code
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| from jinja2.exceptions import TemplateSyntaxError
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| from jinja2._compat import iteritems, reraise, PY2
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| 
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| # on pypy we can take advantage of transparent proxies
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| try:
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|     from __pypy__ import tproxy
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| except ImportError:
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|     tproxy = None
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| 
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| 
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| # how does the raise helper look like?
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| try:
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|     exec("raise TypeError, 'foo'")
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| except SyntaxError:
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|     raise_helper = 'raise __jinja_exception__[1]'
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| except TypeError:
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|     raise_helper = 'raise __jinja_exception__[0], __jinja_exception__[1]'
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| 
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| 
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| class TracebackFrameProxy(object):
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|     """Proxies a traceback frame."""
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| 
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|     def __init__(self, tb):
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|         self.tb = tb
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|         self._tb_next = None
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| 
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|     @property
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|     def tb_next(self):
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|         return self._tb_next
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| 
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|     def set_next(self, next):
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|         if tb_set_next is not None:
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|             try:
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|                 tb_set_next(self.tb, next and next.tb or None)
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|             except Exception:
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|                 # this function can fail due to all the hackery it does
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|                 # on various python implementations.  We just catch errors
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|                 # down and ignore them if necessary.
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|                 pass
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|         self._tb_next = next
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| 
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|     @property
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|     def is_jinja_frame(self):
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|         return '__jinja_template__' in self.tb.tb_frame.f_globals
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| 
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|     def __getattr__(self, name):
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|         return getattr(self.tb, name)
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| 
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| 
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| def make_frame_proxy(frame):
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|     proxy = TracebackFrameProxy(frame)
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|     if tproxy is None:
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|         return proxy
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|     def operation_handler(operation, *args, **kwargs):
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|         if operation in ('__getattribute__', '__getattr__'):
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|             return getattr(proxy, args[0])
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|         elif operation == '__setattr__':
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|             proxy.__setattr__(*args, **kwargs)
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|         else:
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|             return getattr(proxy, operation)(*args, **kwargs)
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|     return tproxy(TracebackType, operation_handler)
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| 
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| 
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| class ProcessedTraceback(object):
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|     """Holds a Jinja preprocessed traceback for printing or reraising."""
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| 
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|     def __init__(self, exc_type, exc_value, frames):
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|         assert frames, 'no frames for this traceback?'
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|         self.exc_type = exc_type
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|         self.exc_value = exc_value
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|         self.frames = frames
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| 
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|         # newly concatenate the frames (which are proxies)
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|         prev_tb = None
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|         for tb in self.frames:
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|             if prev_tb is not None:
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|                 prev_tb.set_next(tb)
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|             prev_tb = tb
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|         prev_tb.set_next(None)
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| 
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|     def render_as_text(self, limit=None):
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|         """Return a string with the traceback."""
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|         lines = traceback.format_exception(self.exc_type, self.exc_value,
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|                                            self.frames[0], limit=limit)
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|         return ''.join(lines).rstrip()
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| 
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|     def render_as_html(self, full=False):
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|         """Return a unicode string with the traceback as rendered HTML."""
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|         from jinja2.debugrenderer import render_traceback
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|         return u'%s\n\n<!--\n%s\n-->' % (
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|             render_traceback(self, full=full),
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|             self.render_as_text().decode('utf-8', 'replace')
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|         )
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| 
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|     @property
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|     def is_template_syntax_error(self):
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|         """`True` if this is a template syntax error."""
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|         return isinstance(self.exc_value, TemplateSyntaxError)
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| 
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|     @property
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|     def exc_info(self):
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|         """Exception info tuple with a proxy around the frame objects."""
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|         return self.exc_type, self.exc_value, self.frames[0]
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| 
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|     @property
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|     def standard_exc_info(self):
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|         """Standard python exc_info for re-raising"""
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|         tb = self.frames[0]
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|         # the frame will be an actual traceback (or transparent proxy) if
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|         # we are on pypy or a python implementation with support for tproxy
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|         if type(tb) is not TracebackType:
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|             tb = tb.tb
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|         return self.exc_type, self.exc_value, tb
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| 
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| 
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| def make_traceback(exc_info, source_hint=None):
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|     """Creates a processed traceback object from the exc_info."""
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|     exc_type, exc_value, tb = exc_info
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|     if isinstance(exc_value, TemplateSyntaxError):
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|         exc_info = translate_syntax_error(exc_value, source_hint)
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|         initial_skip = 0
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|     else:
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|         initial_skip = 1
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|     return translate_exception(exc_info, initial_skip)
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| 
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| 
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| def translate_syntax_error(error, source=None):
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|     """Rewrites a syntax error to please traceback systems."""
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|     error.source = source
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|     error.translated = True
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|     exc_info = (error.__class__, error, None)
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|     filename = error.filename
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|     if filename is None:
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|         filename = '<unknown>'
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|     return fake_exc_info(exc_info, filename, error.lineno)
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| 
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| 
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| def translate_exception(exc_info, initial_skip=0):
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|     """If passed an exc_info it will automatically rewrite the exceptions
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|     all the way down to the correct line numbers and frames.
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|     """
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|     tb = exc_info[2]
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|     frames = []
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| 
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|     # skip some internal frames if wanted
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|     for x in range(initial_skip):
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|         if tb is not None:
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|             tb = tb.tb_next
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|     initial_tb = tb
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| 
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|     while tb is not None:
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|         # skip frames decorated with @internalcode.  These are internal
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|         # calls we can't avoid and that are useless in template debugging
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|         # output.
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|         if tb.tb_frame.f_code in internal_code:
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|             tb = tb.tb_next
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|             continue
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| 
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|         # save a reference to the next frame if we override the current
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|         # one with a faked one.
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|         next = tb.tb_next
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| 
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|         # fake template exceptions
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|         template = tb.tb_frame.f_globals.get('__jinja_template__')
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|         if template is not None:
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|             lineno = template.get_corresponding_lineno(tb.tb_lineno)
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|             tb = fake_exc_info(exc_info[:2] + (tb,), template.filename,
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|                                lineno)[2]
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| 
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|         frames.append(make_frame_proxy(tb))
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|         tb = next
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| 
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|     # if we don't have any exceptions in the frames left, we have to
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|     # reraise it unchanged.
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|     # XXX: can we backup here?  when could this happen?
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|     if not frames:
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|         reraise(exc_info[0], exc_info[1], exc_info[2])
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| 
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|     return ProcessedTraceback(exc_info[0], exc_info[1], frames)
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| 
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| 
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| def get_jinja_locals(real_locals):
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|     ctx = real_locals.get('context')
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|     if ctx:
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|         locals = ctx.get_all()
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|     else:
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|         locals = {}
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| 
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|     local_overrides = {}
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| 
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|     for name, value in iteritems(real_locals):
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|         if not name.startswith('l_') or value is missing:
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|             continue
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|         try:
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|             _, depth, name = name.split('_', 2)
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|             depth = int(depth)
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|         except ValueError:
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|             continue
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|         cur_depth = local_overrides.get(name, (-1,))[0]
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|         if cur_depth < depth:
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|             local_overrides[name] = (depth, value)
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| 
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|     for name, (_, value) in iteritems(local_overrides):
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|         if value is missing:
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|             locals.pop(name, None)
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|         else:
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|             locals[name] = value
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| 
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|     return locals
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| 
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| 
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| def fake_exc_info(exc_info, filename, lineno):
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|     """Helper for `translate_exception`."""
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|     exc_type, exc_value, tb = exc_info
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| 
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|     # figure the real context out
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|     if tb is not None:
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|         locals = get_jinja_locals(tb.tb_frame.f_locals)
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| 
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|         # if there is a local called __jinja_exception__, we get
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|         # rid of it to not break the debug functionality.
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|         locals.pop('__jinja_exception__', None)
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|     else:
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|         locals = {}
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| 
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|     # assamble fake globals we need
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|     globals = {
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|         '__name__':             filename,
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|         '__file__':             filename,
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|         '__jinja_exception__':  exc_info[:2],
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| 
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|         # we don't want to keep the reference to the template around
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|         # to not cause circular dependencies, but we mark it as Jinja
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|         # frame for the ProcessedTraceback
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|         '__jinja_template__':   None
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|     }
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| 
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|     # and fake the exception
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|     code = compile('\n' * (lineno - 1) + raise_helper, filename, 'exec')
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| 
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|     # if it's possible, change the name of the code.  This won't work
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|     # on some python environments such as google appengine
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|     try:
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|         if tb is None:
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|             location = 'template'
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|         else:
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|             function = tb.tb_frame.f_code.co_name
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|             if function == 'root':
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|                 location = 'top-level template code'
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|             elif function.startswith('block_'):
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|                 location = 'block "%s"' % function[6:]
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|             else:
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|                 location = 'template'
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| 
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|         if PY2:
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|             code = CodeType(0, code.co_nlocals, code.co_stacksize,
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|                             code.co_flags, code.co_code, code.co_consts,
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|                             code.co_names, code.co_varnames, filename,
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|                             location, code.co_firstlineno,
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|                             code.co_lnotab, (), ())
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|         else:
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|             code = CodeType(0, code.co_kwonlyargcount,
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|                             code.co_nlocals, code.co_stacksize,
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|                             code.co_flags, code.co_code, code.co_consts,
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|                             code.co_names, code.co_varnames, filename,
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|                             location, code.co_firstlineno,
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|                             code.co_lnotab, (), ())
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|     except Exception as e:
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|         pass
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| 
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|     # execute the code and catch the new traceback
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|     try:
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|         exec(code, globals, locals)
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|     except:
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|         exc_info = sys.exc_info()
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|         new_tb = exc_info[2].tb_next
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| 
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|     # return without this frame
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|     return exc_info[:2] + (new_tb,)
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| 
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| 
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| def _init_ugly_crap():
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|     """This function implements a few ugly things so that we can patch the
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|     traceback objects.  The function returned allows resetting `tb_next` on
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|     any python traceback object.  Do not attempt to use this on non cpython
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|     interpreters
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|     """
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|     import ctypes
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|     from types import TracebackType
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| 
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|     if PY2:
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|         # figure out size of _Py_ssize_t for Python 2:
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|         if hasattr(ctypes.pythonapi, 'Py_InitModule4_64'):
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|             _Py_ssize_t = ctypes.c_int64
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|         else:
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|             _Py_ssize_t = ctypes.c_int
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|     else:
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|         # platform ssize_t on Python 3
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|         _Py_ssize_t = ctypes.c_ssize_t
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| 
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|     # regular python
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|     class _PyObject(ctypes.Structure):
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|         pass
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|     _PyObject._fields_ = [
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|         ('ob_refcnt', _Py_ssize_t),
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|         ('ob_type', ctypes.POINTER(_PyObject))
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|     ]
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| 
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|     # python with trace
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|     if hasattr(sys, 'getobjects'):
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|         class _PyObject(ctypes.Structure):
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|             pass
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|         _PyObject._fields_ = [
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|             ('_ob_next', ctypes.POINTER(_PyObject)),
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|             ('_ob_prev', ctypes.POINTER(_PyObject)),
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|             ('ob_refcnt', _Py_ssize_t),
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|             ('ob_type', ctypes.POINTER(_PyObject))
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|         ]
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| 
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|     class _Traceback(_PyObject):
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|         pass
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|     _Traceback._fields_ = [
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|         ('tb_next', ctypes.POINTER(_Traceback)),
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|         ('tb_frame', ctypes.POINTER(_PyObject)),
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|         ('tb_lasti', ctypes.c_int),
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|         ('tb_lineno', ctypes.c_int)
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|     ]
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| 
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|     def tb_set_next(tb, next):
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|         """Set the tb_next attribute of a traceback object."""
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|         if not (isinstance(tb, TracebackType) and
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|                 (next is None or isinstance(next, TracebackType))):
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|             raise TypeError('tb_set_next arguments must be traceback objects')
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|         obj = _Traceback.from_address(id(tb))
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|         if tb.tb_next is not None:
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|             old = _Traceback.from_address(id(tb.tb_next))
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|             old.ob_refcnt -= 1
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|         if next is None:
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|             obj.tb_next = ctypes.POINTER(_Traceback)()
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|         else:
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|             next = _Traceback.from_address(id(next))
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|             next.ob_refcnt += 1
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|             obj.tb_next = ctypes.pointer(next)
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| 
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|     return tb_set_next
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| 
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| 
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| # try to get a tb_set_next implementation if we don't have transparent
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| # proxies.
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| tb_set_next = None
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| if tproxy is None:
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|     try:
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|         tb_set_next = _init_ugly_crap()
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|     except:
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|         pass
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|     del _init_ugly_crap
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| 
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