Conversions for typeCompatibleWith produce incorrect assertions

[hakanai]

Currently, these:

assertThat(x, is(typeCompatibleWith(Y.class)));
assertThat(x, is(not(typeCompatibleWith(Y.class))));

Are replaced by these:

assertThat(x).isInstanceOf(Y.class);
assertThat(x).isAssignableFrom(Y.class);

But both of these are wrong.

Hamcrest's typeCompatibleWith is equivalent to a reverse isAssignableFrom check, and AssertJ appears to have no equivalent at present (currently v3.22.0).

Really, it seems like AssertJ wants an isAssignableTo / isNotAssignableTo pair.

This was seemingly requested but they ended up implementing only hasSuperclass which only checks the immediate superclass. :(

[hakanai]

I couldn't find an existing ticket over in AssertJ so I also filed assertj-core #2545.