How to write integration test for filter in grails

I have written one filter rule which I want to test using grails integration tests. Filter is

invalidAccess(controller: "home") {
    before = {
            redirect(controller: "newHome", action: "index")
            return false
    }
}

I have followed this link to write the integration test http://ldaley.com/post/392153102/integration-testing-grails-filters

It returns result as false But gives

null for redirectedUrl

instead of newHome & index method url. What am I missing here?

import grails.util.GrailsWebUtil

class MyFilterTests extends GroovyTestCase {

    def filterInterceptor
    def grailsApplication
    def grailsWebRequest

    def request(Map params, controllerName, actionName) {
        grailsWebRequest = GrailsWebUtil.bindMockWebRequest(grailsApplication.mainContext)
        grailsWebRequest.params.putAll(params)
        grailsWebRequest.controllerName = controllerName
        grailsWebRequest.actionName = actionName
        filterInterceptor.preHandle(grailsWebRequest.request, grailsWebRequest.response, null)
    }

    def getResponse() {
        grailsWebRequest.currentResponse
    }

    def testFilterRedirects() {
        def result = request( someParameter: "2", "home", "index")
        assertFalse result
        assertTrue response.redirectedUrl.endsWith(/* something */)
    }

}

If you want to try unit testing and need to mock some services then you can mock like:

@TestFor(SomethingToTest)
@Mock([FirstService, SecondService])
class SomethingToTestSpec extends Specification {

and you want integration test then try following test

import grails.util.GrailsWebUtil
import org.junit.After
import org.junit.Before
import org.junit.Test

class MyFilterIntegrationTests {

    def filterInterceptor
    def grailsApplication
    def grailsWebRequest

    @Before
    void setUp() {
    }

    @After
    void tearDown() {
    }

    @Test
    void testFilterRedirects() {
        def result = request("person", "index", someParameter: "2")
        assert !result
        assert response.redirectedUrl.endsWith('/auth/index')
    }

    def getResponse() {
        grailsWebRequest.currentResponse
    }

    def request(Map params, controllerName, actionName) {
        grailsWebRequest = GrailsWebUtil.bindMockWebRequest(grailsApplication.mainContext)
        grailsWebRequest.params.putAll(params)
        grailsWebRequest.controllerName = controllerName
        grailsWebRequest.actionName = actionName
        filterInterceptor.preHandle(grailsWebRequest.request, grailsWebRequest.response, null)
    }
}

Ref# Grails Integration Test Filter