From a93fc02af6eb50ecb0cfc69174c9f385d60bbbb3 Mon Sep 17 00:00:00 2001 From: Petr Viktorin Date: Mon, 23 Sep 2013 10:46:01 +0200 Subject: Raise an error when updating CIDict with duplicate keys Updating a CIDict with data like {'A': 1, 'a': 2} would lead to data loss since only one of the items would get to the CIDict. This can result in non-obvious bugs similar to this one in python-ldap: https://bugzilla.redhat.com/show_bug.cgi?id=1007820 Raise an error in this case; any resolution must be done by the caller. --- ipapython/ipautil.py | 25 ++++++++++++++++++++++--- 1 file changed, 22 insertions(+), 3 deletions(-) (limited to 'ipapython') diff --git a/ipapython/ipautil.py b/ipapython/ipautil.py index c5b47f5b..13d24279 100644 --- a/ipapython/ipautil.py +++ b/ipapython/ipautil.py @@ -455,8 +455,18 @@ class CIDict(dict): def __getitem__(self, key): return super(CIDict, self).__getitem__(key.lower()) - def __setitem__(self, key, value): + def __setitem__(self, key, value, seen_keys=None): + """cidict[key] = value + + The ``seen_keys`` argument is used by ``update()`` to keep track of + duplicate keys. It should be an initially empty set that is + passed to all calls to __setitem__ that should not set duplicate keys. + """ lower_key = key.lower() + if seen_keys is not None: + if lower_key in seen_keys: + raise ValueError('Duplicate key in update: %s' % key) + seen_keys.add(lower_key) self._keys[lower_key] = key return super(CIDict, self).__setitem__(lower_key, value) @@ -466,6 +476,14 @@ class CIDict(dict): return super(CIDict, self).__delitem__(lower_key) def update(self, new=None, **kwargs): + """Update self from dict/iterable new and kwargs + + Functions like ``dict.update()``. + + Neither ``new`` nor ``kwargs`` may contain two keys that only differ in + case, as this situation would result in loss of data. + """ + seen = set() if new: try: keys = new.keys @@ -473,9 +491,10 @@ class CIDict(dict): self.update(dict(new)) else: for key in keys(): - self[key] = new[key] + self.__setitem__(key, new[key], seen) + seen = set() for key, value in kwargs.iteritems(): - self[key] = value + self.__setitem__(key, value, seen) def __contains__(self, key): return super(CIDict, self).__contains__(key.lower()) -- cgit