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# -*- coding: utf-8 -*-
"""
werkzeug.debug.repr
~~~~~~~~~~~~~~~~~~~
This module implements object representations for debugging purposes.
Unlike the default repr these reprs expose a lot more information and
produce HTML instead of ASCII.
Together with the CSS and JavaScript files of the debugger this gives
a colorful and more compact output.
:copyright: (c) 2014 by the Werkzeug Team, see AUTHORS for more details.
:license: BSD.
"""
import sys
import re
import codecs
from traceback import format_exception_only
try:
from collections import deque
except ImportError: # pragma: no cover
deque = None
from werkzeug.utils import escape
from werkzeug._compat import iteritems, PY2, text_type, integer_types, \
string_types
missing = object()
_paragraph_re = re.compile(r'(?:\r\n|\r|\n){2,}')
RegexType = type(_paragraph_re)
HELP_HTML = '''\
<div class=box>
<h3>%(title)s</h3>
<pre class=help>%(text)s</pre>
</div>\
'''
OBJECT_DUMP_HTML = '''\
<div class=box>
<h3>%(title)s</h3>
%(repr)s
<table>%(items)s</table>
</div>\
'''
def debug_repr(obj):
"""Creates a debug repr of an object as HTML unicode string."""
return DebugReprGenerator().repr(obj)
def dump(obj=missing):
"""Print the object details to stdout._write (for the interactive
console of the web debugger.
"""
gen = DebugReprGenerator()
if obj is missing:
rv = gen.dump_locals(sys._getframe(1).f_locals)
else:
rv = gen.dump_object(obj)
sys.stdout._write(rv)
class _Helper(object):
"""Displays an HTML version of the normal help, for the interactive
debugger only because it requires a patched sys.stdout.
"""
def __repr__(self):
return 'Type help(object) for help about object.'
def __call__(self, topic=None):
if topic is None:
sys.stdout._write('<span class=help>%s</span>' % repr(self))
return
import pydoc
pydoc.help(topic)
rv = sys.stdout.reset()
if isinstance(rv, bytes):
rv = rv.decode('utf-8', 'ignore')
paragraphs = _paragraph_re.split(rv)
if len(paragraphs) > 1:
title = paragraphs[0]
text = '\n\n'.join(paragraphs[1:])
else: # pragma: no cover
title = 'Help'
text = paragraphs[0]
sys.stdout._write(HELP_HTML % {'title': title, 'text': text})
helper = _Helper()
def _add_subclass_info(inner, obj, base):
if isinstance(base, tuple):
for base in base:
if type(obj) is base:
return inner
elif type(obj) is base:
return inner
module = ''
if obj.__class__.__module__ not in ('__builtin__', 'exceptions'):
module = '<span class="module">%s.</span>' % obj.__class__.__module__
return '%s%s(%s)' % (module, obj.__class__.__name__, inner)
class DebugReprGenerator(object):
def __init__(self):
self._stack = []
def _sequence_repr_maker(left, right, base=object(), limit=8):
def proxy(self, obj, recursive):
if recursive:
return _add_subclass_info(left + '...' + right, obj, base)
buf = [left]
have_extended_section = False
for idx, item in enumerate(obj):
if idx:
buf.append(', ')
if idx == limit:
buf.append('<span class="extended">')
have_extended_section = True
buf.append(self.repr(item))
if have_extended_section:
buf.append('</span>')
buf.append(right)
return _add_subclass_info(u''.join(buf), obj, base)
return proxy
list_repr = _sequence_repr_maker('[', ']', list)
tuple_repr = _sequence_repr_maker('(', ')', tuple)
set_repr = _sequence_repr_maker('set([', '])', set)
frozenset_repr = _sequence_repr_maker('frozenset([', '])', frozenset)
if deque is not None:
deque_repr = _sequence_repr_maker('<span class="module">collections.'
'</span>deque([', '])', deque)
del _sequence_repr_maker
def regex_repr(self, obj):
pattern = repr(obj.pattern)
if PY2:
pattern = pattern.decode('string-escape', 'ignore')
else:
pattern = codecs.decode(pattern, 'unicode-escape', 'ignore')
if pattern[:1] == 'u':
pattern = 'ur' + pattern[1:]
else:
pattern = 'r' + pattern
return u're.compile(<span class="string regex">%s</span>)' % pattern
def string_repr(self, obj, limit=70):
buf = ['<span class="string">']
escaped = escape(obj)
a = repr(escaped[:limit])
b = repr(escaped[limit:])
if isinstance(obj, text_type) and PY2:
buf.append('u')
a = a[1:]
b = b[1:]
if b != "''":
buf.extend((a[:-1], '<span class="extended">', b[1:], '</span>'))
else:
buf.append(a)
buf.append('</span>')
return _add_subclass_info(u''.join(buf), obj, (bytes, text_type))
def dict_repr(self, d, recursive, limit=5):
if recursive:
return _add_subclass_info(u'{...}', d, dict)
buf = ['{']
have_extended_section = False
for idx, (key, value) in enumerate(iteritems(d)):
if idx:
buf.append(', ')
if idx == limit - 1:
buf.append('<span class="extended">')
have_extended_section = True
buf.append('<span class="pair"><span class="key">%s</span>: '
'<span class="value">%s</span></span>' %
(self.repr(key), self.repr(value)))
if have_extended_section:
buf.append('</span>')
buf.append('}')
return _add_subclass_info(u''.join(buf), d, dict)
def object_repr(self, obj):
r = repr(obj)
if PY2:
r = r.decode('utf-8', 'replace')
return u'<span class="object">%s</span>' % escape(r)
def dispatch_repr(self, obj, recursive):
if obj is helper:
return u'<span class="help">%r</span>' % helper
if isinstance(obj, (integer_types, float, complex)):
return u'<span class="number">%r</span>' % obj
if isinstance(obj, string_types):
return self.string_repr(obj)
if isinstance(obj, RegexType):
return self.regex_repr(obj)
if isinstance(obj, list):
return self.list_repr(obj, recursive)
if isinstance(obj, tuple):
return self.tuple_repr(obj, recursive)
if isinstance(obj, set):
return self.set_repr(obj, recursive)
if isinstance(obj, frozenset):
return self.frozenset_repr(obj, recursive)
if isinstance(obj, dict):
return self.dict_repr(obj, recursive)
if deque is not None and isinstance(obj, deque):
return self.deque_repr(obj, recursive)
return self.object_repr(obj)
def fallback_repr(self):
try:
info = ''.join(format_exception_only(*sys.exc_info()[:2]))
except Exception: # pragma: no cover
info = '?'
if PY2:
info = info.decode('utf-8', 'ignore')
return u'<span class="brokenrepr"><broken repr (%s)>' \
u'</span>' % escape(info.strip())
def repr(self, obj):
recursive = False
for item in self._stack:
if item is obj:
recursive = True
break
self._stack.append(obj)
try:
try:
return self.dispatch_repr(obj, recursive)
except Exception:
return self.fallback_repr()
finally:
self._stack.pop()
def dump_object(self, obj):
repr = items = None
if isinstance(obj, dict):
title = 'Contents of'
items = []
for key, value in iteritems(obj):
if not isinstance(key, string_types):
items = None
break
items.append((key, self.repr(value)))
if items is None:
items = []
repr = self.repr(obj)
for key in dir(obj):
try:
items.append((key, self.repr(getattr(obj, key))))
except Exception:
pass
title = 'Details for'
title += ' ' + object.__repr__(obj)[1:-1]
return self.render_object_dump(items, title, repr)
def dump_locals(self, d):
items = [(key, self.repr(value)) for key, value in d.items()]
return self.render_object_dump(items, 'Local variables in frame')
def render_object_dump(self, items, title, repr=None):
html_items = []
for key, value in items:
html_items.append('<tr><th>%s<td><pre class=repr>%s</pre>' %
(escape(key), value))
if not html_items:
html_items.append('<tr><td><em>Nothing</em>')
return OBJECT_DUMP_HTML % {
'title': escape(title),
'repr': repr and '<pre class=repr>%s</pre>' % repr or '',
'items': '\n'.join(html_items)
}
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