Yup, precisely should work fine with mutable / unhashable types -- it just relies on equality to check the elements in an iterable. More specifically, writing:

Yup, precisely should work fine with mutable / unhashable types -- it just relies on equality to check the elements in an iterable. More specifically, writing: contains_exactly("a", "b") is equivalent to: contains_exactly(equal_to("a"), equal_to("b"))