diff options
Diffstat (limited to 'django/utils/datastructures.py')
| -rw-r--r-- | django/utils/datastructures.py | 50 |
1 files changed, 41 insertions, 9 deletions
diff --git a/django/utils/datastructures.py b/django/utils/datastructures.py index 21a72f2d1e..f27bc1cfff 100644 --- a/django/utils/datastructures.py +++ b/django/utils/datastructures.py @@ -332,17 +332,49 @@ class DotExpandedDict(dict): except TypeError: # Special-case if current isn't a dict. current = {bits[-1]: v} -class FileDict(dict): +class ImmutableList(tuple): """ - A dictionary used to hold uploaded file contents. The only special feature - here is that repr() of this object won't dump the entire contents of the - file to the output. A handy safeguard for a large file upload. + A tuple-like object that raises useful errors when it is asked to mutate. + + Example:: + + >>> a = ImmutableList(range(5), warning="You cannot mutate this.") + >>> a[3] = '4' + Traceback (most recent call last): + ... + AttributeError: You cannot mutate this. """ - def __repr__(self): - if 'content' in self: - d = dict(self, content='<omitted>') - return dict.__repr__(d) - return dict.__repr__(self) + + def __new__(cls, *args, **kwargs): + if 'warning' in kwargs: + warning = kwargs['warning'] + del kwargs['warning'] + else: + warning = 'ImmutableList object is immutable.' + self = tuple.__new__(cls, *args, **kwargs) + self.warning = warning + return self + + def complain(self, *wargs, **kwargs): + if isinstance(self.warning, Exception): + raise self.warning + else: + raise AttributeError, self.warning + + # All list mutation functions complain. + __delitem__ = complain + __delslice__ = complain + __iadd__ = complain + __imul__ = complain + __setitem__ = complain + __setslice__ = complain + append = complain + extend = complain + insert = complain + pop = complain + remove = complain + sort = complain + reverse = complain class DictWrapper(dict): """ |
