add unit test for Next button link in Log view Change-Id: Id2c121148fee158af30fb848e80449078b4fd31b

diff --git a/javatests/com/google/gitiles/LogServletTest.java b/javatests/com/google/gitiles/LogServletTest.java
index 94c2e38..3ad90a8 100644
--- a/javatests/com/google/gitiles/LogServletTest.java
+++ b/javatests/com/google/gitiles/LogServletTest.java

@@ -167,4 +167,32 @@
                 + "&amp;n=2"
                 + "\">");
   }
+
+  @Test
+  public void verifyNextButtonAction() throws Exception {
+    repo.branch(MAIN).commit().add("foo", "contents").create();
+    RevCommit grandParent = repo.branch(MAIN).commit().add("foo", "contents").create();
+    RevCommit parent =
+        repo.branch(MAIN).commit().parent(grandParent).add("foo", "contents").create();
+    RevCommit main = repo.branch(MAIN).commit().parent(parent).create();
+
+    int numCommitsPerPage = 1;
+    String path =
+        "/repo/+log/" + grandParent.toObjectId().getName() + ".." + main.toObjectId().getName();
+    FakeHttpServletResponse res =
+        buildResponse(path, "format=html" + "&n=" + numCommitsPerPage, SC_OK);
+
+    assertThat(res.getActualBodyString())
+        .contains(
+            "<a class=\"LogNav-next\""
+                + " href=\"/b/repo/+log/"
+                + grandParent.toObjectId().getName()
+                + ".."
+                + main.toObjectId().getName()
+                + "/?format=html"
+                + "&amp;n=1"
+                + "&amp;s="
+                + parent.toObjectId().getName()
+                + "\">");
+  }
 }