in case expectedException isn't null, but runnable::run hasn't thrown any exception, runAndCheckException will throw AssertionError which will be caught in catch block and exception type will be checked w/ expectedException.
that causes an extra (incorrect) exception wrapping, and also can cause false negative result (if expectedException == AssertionError.class)

public static void runAndCheckException(Runnable runnable, Class<? extends Throwable> expectedException) {
        try {
            runnable.run();
            if (expectedException != null) {
                throw new AssertionError("Didn't get expected exception " + expectedException.getSimpleName());
            }
        } catch (Throwable t) {
            if (expectedException == null) {
                throw new AssertionError("Got unexpected exception ", t);
            }
            if (!expectedException.isAssignableFrom(t.getClass())) {
                throw new AssertionError(String.format("Got unexpected exception %s instead of %s",
                        t.getClass().getSimpleName(), expectedException.getSimpleName()), t);
            }
        }
    }