"""Redo the builtin repr() (representation) but with limits on most sizes."""
__all__ = ["Repr", "repr", "recursive_repr"]
import builtins
from itertools import islice
from _thread import get_ident
def recursive_repr(fillvalue='...'):
'Decorator to make a repr function return fillvalue for a recursive call'
def decorating_function(user_function):
repr_running = set()
def wrapper(self):
key = id(self), get_ident()
if key in repr_running:
return fillvalue
repr_running.add(key)
try:
result = user_function(self)
finally:
repr_running.discard(key)
return result
# Can't use functools.wraps() here because of bootstrap issues
wrapper.__module__ = getattr(user_function, '__module__')
wrapper.__doc__ = getattr(user_function, '__doc__')
wrapper.__name__ = getattr(user_function, '__name__')
wrapper.__qualname__ = getattr(user_function, '__qualname__')
wrapper.__annotations__ = getattr(user_function, '__annotations__', {})
wrapper.__type_params__ = getattr(user_function, '__type_params__', ())
wrapper.__wrapped__ = user_function
return wrapper
return decorating_function
class Repr:
_lookup = {
'tuple': 'builtins',
'list': 'builtins',
'array': 'array',
'set': 'builtins',
'frozenset': 'builtins',
'deque': 'collections',
'dict': 'builtins',
'str': 'builtins',
'int': 'builtins'
}
def __init__(
self, *, maxlevel=6, maxtuple=6, maxlist=6, maxarray=5, maxdict=4,
maxset=6, maxfrozenset=6, maxdeque=6, maxstring=30, maxlong=40,
maxother=30, fillvalue='...', indent=None,
):
self.maxlevel = maxlevel
self.maxtuple = maxtuple
self.maxlist = maxlist
self.maxarray = maxarray
self.maxdict = maxdict
self.maxset = maxset
self.maxfrozenset = maxfrozenset
self.maxdeque = maxdeque
self.maxstring = maxstring
self.maxlong = maxlong
self.maxother = maxother
self.fillvalue = fillvalue
self.indent = indent
def repr(self, x):
return self.repr1(x, self.maxlevel)
def repr1(self, x, level):
cls = type(x)
typename = cls.__name__
if ' ' in typename:
parts = typename.split()
typename = '_'.join(parts)
method = getattr(self, 'repr_' + typename, None)
if method:
# not defined in this class
if typename not in self._lookup:
return method(x, level)
module = getattr(cls, '__module__', None)
# defined in this class and is the module intended
if module == self._lookup[typename]:
return method(x, level)
return self.repr_instance(x, level)
def _join(self, pieces, level):
if self.indent is None:
return ', '.join(pieces)
if not pieces:
return ''
indent = self.indent
if isinstance(indent, int):
if indent < 0:
raise ValueError(
f'Repr.indent cannot be negative int (was {indent!r})'
)
indent *= ' '
try:
sep = ',\n' + (self.maxlevel - level + 1) * indent
except TypeError as error:
raise TypeError(
f'Repr.indent must be a str, int or None, not {type(indent)}'
) from error
return sep.join(('', *pieces, ''))[1:-len(indent) or None]
def _repr_iterable(self, x, level, left, right, maxiter, trail=''):
n = len(x)
if level <= 0 and n:
s = self.fillvalue
else:
newlevel = level - 1
repr1 = self.repr1
pieces = [repr1(elem, newlevel) for elem in islice(x, maxiter)]
if n > maxiter:
pieces.append(self.fillvalue)
s = self._join(pieces, level)
if n == 1 and trail and self.indent is None:
right = trail + right
return '%s%s%s' % (left, s, right)
def repr_tuple(self, x, level):
return self._repr_iterable(x, level, '(', ')', self.maxtuple, ',')
def repr_list(self, x, level):
return self._repr_iterable(x, level, '[', ']', self.maxlist)
def repr_array(self, x, level):
if not x:
return "array('%s')" % x.typecode
header = "array('%s', [" % x.typecode
return self._repr_iterable(x, level, header, '])', self.maxarray)
def repr_set(self, x, level):
if not x:
return 'set()'
x = _possibly_sorted(x)
return self._repr_iterable(x, level, '{', '}', self.maxset)
def repr_frozenset(self, x, level):
if not x:
return 'frozenset()'
x = _possibly_sorted(x)
return self._repr_iterable(x, level, 'frozenset({', '})',
self.maxfrozenset)
def repr_deque(self, x, level):
return self._repr_iterable(x, level, 'deque([', '])', self.maxdeque)
def repr_dict(self, x, level):
n = len(x)
if n == 0:
return '{}'
if level <= 0:
return '{' + self.fillvalue + '}'
newlevel = level - 1
repr1 = self.repr1
pieces = []
for key in islice(_possibly_sorted(x), self.maxdict):
keyrepr = repr1(key, newlevel)
valrepr = repr1(x[key], newlevel)
pieces.append('%s: %s' % (keyrepr, valrepr))
if n > self.maxdict:
pieces.append(self.fillvalue)
s = self._join(pieces, level)
return '{%s}' % (s,)
def repr_str(self, x, level):
s = builtins.repr(x[:self.maxstring])
if len(s) > self.maxstring:
i = max(0, (self.maxstring-3)//2)
j = max(0, self.maxstring-3-i)
s = builtins.repr(x[:i] + x[len(x)-j:])
s = s[:i] + self.fillvalue + s[len(s)-j:]
return s
def repr_int(self, x, level):
s = builtins.repr(x) # XXX Hope this isn't too slow...
if len(s) > self.maxlong:
i = max(0, (self.maxlong-3)//2)
j = max(0, self.maxlong-3-i)
s = s[:i] + self.fillvalue + s[len(s)-j:]
return s
def repr_instance(self, x, level):
try:
s = builtins.repr(x)
# Bugs in x.__repr__() can cause arbitrary
# exceptions -- then make up something
except Exception:
return '<%s instance at %#x>' % (x.__class__.__name__, id(x))
if len(s) > self.maxother:
i = max(0, (self.maxother-3)//2)
j = max(0, self.maxother-3-i)
s = s[:i] + self.fillvalue + s[len(s)-j:]
return s
def _possibly_sorted(x):
# Since not all sequences of items can be sorted and comparison
# functions may raise arbitrary exceptions, return an unsorted
# sequence in that case.
try:
return sorted(x)
except Exception:
return list(x)
aRepr = Repr()
repr = aRepr.repr
