verify(this.mechContext, times(1)).supportsIntegrity();
    }

    @Test
    @DisplayName("isPreferredMech delegates to underlying mechanism context")
    void testIsPreferredMechDelegates() {
        SpnegoContext ctx = newContext();
        ASN1ObjectIdentifier mech = new ASN1ObjectIdentifier("1.2.840.113554.1.2.2");
        when(this.mechContext.isPreferredMech(mech)).thenReturn(true);