fix tests that broke with redis 2.8
diff --git a/.gitignore b/.gitignore
index 83e4a40..83d2084 100644
--- a/.gitignore
+++ b/.gitignore
@@ -11,3 +11,4 @@
 *.ipr
 *.iws
 .idea
+out
diff --git a/grails-app/services/grails/plugin/redis/RedisService.groovy b/grails-app/services/grails/plugin/redis/RedisService.groovy
index bde564e..876fd8f 100644
--- a/grails-app/services/grails/plugin/redis/RedisService.groovy
+++ b/grails-app/services/grails/plugin/redis/RedisService.groovy
@@ -22,6 +22,7 @@
 class RedisService {
 
     public static final int NO_EXPIRATION_TTL = -1
+    public static final int KEY_DOES_NOT_EXIST = -2  // added in redis 2.8
 
     def redisPool
     def grailsApplication
diff --git a/test/projects/default/test/integration/grails/plugin/redis/RedisIntegrationTests.groovy b/test/projects/default/test/integration/grails/plugin/redis/RedisIntegrationTests.groovy
index 14848c1..1a3be75 100644
--- a/test/projects/default/test/integration/grails/plugin/redis/RedisIntegrationTests.groovy
+++ b/test/projects/default/test/integration/grails/plugin/redis/RedisIntegrationTests.groovy
@@ -1,6 +1,8 @@
 package grails.plugin.redis
 
 import com.example.Book
+
+import static grails.plugin.redis.RedisService.KEY_DOES_NOT_EXIST
 import static grails.plugin.redis.RedisService.NO_EXPIRATION_TTL
 
 class RedisIntegrationTests extends GroovyTestCase {
@@ -40,7 +42,7 @@
 
     def testMemoizeDomainListWithExpire() {
         def book1 = Book.build(title: "book1")
-        assertEquals NO_EXPIRATION_TTL, redisService.ttl("domainkey")
+        assert KEY_DOES_NOT_EXIST == redisService.ttl("domainkey")
         def result = redisService.memoizeDomainList(Book, "domainkey", 60) { [book1] }
         assertEquals([book1], result)
         assertTrue NO_EXPIRATION_TTL < redisService.ttl("domainkey")