dict_diff.py

def dict_diff1(first, second, NO_KEY='<KEYNOTFOUND>'):
    """ Return a dict of keys that differ with another config object.  If a value is
        not found in one fo the configs, it will be represented by NO_KEY.
        @param first:   Fist dictionary to diff.
        @param second:  Second dicationary to diff.
        @return diff:   Dict of Key => (first.val, second.val)
    """
    diff = {}
    # Check all keys in first dict
    for key in first.keys():
        if (not second.has_key(key)):
            diff[key] = (first[key], NO_KEY)
        elif (first[key] != second[key]):
            diff[key] = (first[key], second[key])
    # Check all keys in second dict to find missing
    for key in second.keys():
        if (not first.has_key(key)):
            diff[key] = (NO_KEY, second[key])
    return diff

def dict_diff2(dict_a, dict_b):
    return dict([
        (key, dict_b.get(key, dict_a.get(key)))
        for key in set(dict_a.keys()+dict_b.keys())
        if (
            (key in dict_a and (not key in dict_b or dict_a[key] != dict_b[key])) or
            (key in dict_b and (not key in dict_a or dict_a[key] != dict_b[key]))
        )
    ])

def dict_diff3(d1, d2, NO_KEY='<KEYNOTFOUND>'):
    d1k = set(d1)
    d2k = set(d2)
    both = d1k & d2k
    diff = {k:(d1[k], d2[k]) for k in both if d1[k] != d2[k]}
    diff.update({k:(d1[k], NO_KEY) for k in d1k - both})
    diff.update({k:(NO_KEY, d2[k]) for k in d2k - both})
    return diff