"""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__', ()) return wrapper return decorating_function class Repr: 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): typename = type(x).__name__ if ' ' in typename: parts = typename.split() typename = '_'.join(parts) if hasattr(self, 'repr_' + typename): return getattr(self, 'repr_' + typename)(x, level) else: 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