add basic test for PageConfig#isNotModified()

Author: vladak

opengrok-web/src/main/java/org/opengrok/web/PageConfig.java

@@ -1842,7 +1842,6 @@ public boolean isNotModified(HttpServletRequest request, HttpServletResponse res
         );
 
         String headerEtag = request.getHeader(HttpHeaders.IF_NONE_MATCH);
-
         if (headerEtag != null && headerEtag.equals(currentEtag)) {
             // weak ETag has not changed, return 304 NOT MODIFIED
             response.setStatus(HttpServletResponse.SC_NOT_MODIFIED);

opengrok-web/src/test/java/org/opengrok/web/PageConfigTest.java

@@ -39,6 +39,8 @@
 import java.util.stream.Stream;
 
 import jakarta.servlet.http.HttpServletRequest;
+import jakarta.servlet.http.HttpServletResponse;
+import jakarta.ws.rs.core.HttpHeaders;
 import org.apache.commons.lang3.tuple.Pair;
 import org.junit.jupiter.api.AfterAll;
 import org.junit.jupiter.api.BeforeAll;
@@ -47,6 +49,7 @@
 import org.junit.jupiter.api.condition.OS;
 import org.junit.jupiter.params.ParameterizedTest;
 import org.junit.jupiter.params.provider.MethodSource;
+import org.mockito.Mockito;
 import org.opengrok.indexer.authorization.AuthControlFlag;
 import org.opengrok.indexer.authorization.AuthorizationFramework;
 import org.opengrok.indexer.authorization.AuthorizationPlugin;
@@ -68,6 +71,8 @@
 import static org.junit.jupiter.api.Assertions.assertThrows;
 import static org.junit.jupiter.api.Assertions.assertTrue;
 import static org.junit.jupiter.api.Assumptions.assumeTrue;
+import static org.mockito.ArgumentMatchers.eq;
+import static org.mockito.ArgumentMatchers.startsWith;
 import static org.opengrok.indexer.condition.RepositoryInstalled.Type.MERCURIAL;
 import static org.opengrok.indexer.history.LatestRevisionUtil.getLatestRevision;
 
@@ -647,4 +652,27 @@ public String getPathInfo() {
             }
         };
     }
+
+    @Test
+    void testIsNotModified() {
+        HttpServletRequest req = new DummyHttpServletRequest() {
+            @Override
+            public String getHeader(String name) {
+                if (name.equals(HttpHeaders.IF_NONE_MATCH)) {
+                    return "foo"; // will not match the hash computed in
+                }
+                return null;
+            }
+
+            @Override
+            public String getPathInfo() {
+                return "path";
+            }
+        };
+
+        PageConfig cfg = PageConfig.get(req);
+        HttpServletResponse resp = Mockito.mock(HttpServletResponse.class);
+        assertFalse(cfg.isNotModified(req, resp));
+        Mockito.verify(resp).setHeader(eq(HttpHeaders.ETAG), startsWith("W/"));
+    }
 }