verify(this.mechContext, never()).initSecContext(any(), anyInt(), anyInt());
    }

    @Test
    @DisplayName("getSigningKey delegates to underlying mechanism context")
    void testGetSigningKeyDelegates() throws Exception {
        SpnegoContext ctx = newContext();
        byte[] key = new byte[] { 1, 2, 3 };
        when(this.mechContext.getSigningKey()).thenReturn(key);