private void CompareLookups1(ILookup <string, int> look1, CachingDictionary <string, int> look2, HashSet <string> keys)
{
foreach (string k in keys)
{
Assert.Equal(look1.Contains(k), look2.Contains(k));
CheckEqualEnumerable(look1[k], look2[k]);
}
foreach (string k in new string[] { "goo", "bar", "banana", "flibber" })
{
Assert.False(look1.Contains(k));
Assert.False(look2.Contains(k));
Assert.Empty(look1[k]);
Assert.Empty(look2[k]);
}
}