True (Unit) Test Integration

[Nordlöw]

As each symbol in obarray can contain properties/attributes using put
() and get() wouldn't it be really useful to use this feature to
enable "true" unit-test integration with code in the following way;

When a function definition of symbol is changed we use the value of
the property say :tester; If this value is function we call this
function with function and report its output kind of like for example
elk does.

Similarly for packages a unit-test could be run every time a package-
file is compiled by using eval-when-compile(), right?

Does anyone know of any test package that uses this idea. I believe
Python have something similar, doesn't it?

Thanks in advance,
Nordlöw