test.setHeader("set-header", "new value");
verify(response).setHeader("set-header", "new value");
test.setHeader("content-length", "content length value");
verify(response, never()).setHeader("content-length", "content length value");
test.sendRedirect("location");
verify(response).sendRedirect("location");
test.flushBuffer();
verify(response).flushBuffer();