public void Except()
{
//given
var src = new Dictionary <string, object> {
{ "one", "1" }, { "two", 2 }, { "four", new double[] { 4.1, 4.2, 4.3 } }
};
//when
var test = Dictionaries.Except(src, new HashSet <string> {
"two", "four"
});
var empty = Dictionaries.Except(src, new HashSet <string> {
"two", "four", "one"
});
//then
Assert.NotSame(test, src);
Assert.Equal(1, test.Count);
Assert.Equal("1", test["one"]);
Assert.Null(empty);
}