libtest-identity-perl

test module that asserts the referential identity of a reference
Test::Identity provides a single testing function, identical. It asserts that
a given reference is as expected; that is, it either refers to the same
object or is undef. It is similar to Test::More::is except that it uses
refaddr, ensuring that it behaves correctly even if the references under test
are objects that overload stringification or numification. It also provides
better diagnostics if the test fails.