HIVE-29470: Add unit test to verify commonLocalResources after openin…

ql/src/java/org/apache/hadoop/hive/ql/exec/tez/TezSessionState.java

@@ -302,6 +302,20 @@ protected void openInternal(String[] additionalFilesNotFromConf,
     }
   }
 
+  /**
+   * Builds the map of common local resources (app jar + localized resources) for the Tez session.
+   * Extracted for testability to ensure resources are properly registered.
+   */
+  @VisibleForTesting
+  Map<String, LocalResource> buildCommonLocalResources() {
+    final Map<String, LocalResource> commonLocalResources = new HashMap<>();
+    commonLocalResources.put(DagUtils.getBaseName(appJarLr), appJarLr);
+    for (LocalResource lr : this.resources.localizedResources) {
+      commonLocalResources.put(DagUtils.getBaseName(lr), lr);
+    }
+    return commonLocalResources;
+  }
+
   /**
    * Opens a Tez session without performing a complete rollback/cleanup on failure.
    *
@@ -318,14 +332,9 @@ protected void openInternal(String[] additionalFilesNotFromConf,
    */
   @VisibleForTesting
   void openInternalUnsafe(boolean isAsync, LogHelper console) throws TezException, IOException {
-    final Map<String, LocalResource> commonLocalResources = new HashMap<>();
+    final Map<String, LocalResource> commonLocalResources = buildCommonLocalResources();
     final boolean llapMode = "llap".equalsIgnoreCase(HiveConf.getVar(conf, HiveConf.ConfVars.HIVE_EXECUTION_MODE));
 
-    commonLocalResources.put(DagUtils.getBaseName(appJarLr), appJarLr);
-    for (LocalResource lr : this.resources.localizedResources) {
-      commonLocalResources.put(DagUtils.getBaseName(lr), lr);
-    }
-
     if (llapMode) {
       // localize llap client jars
       addJarLRByClass(LlapTaskSchedulerService.class, commonLocalResources);

ql/src/test/org/apache/hadoop/hive/ql/exec/tez/TestTezSessionState.java

@@ -21,6 +21,7 @@
 import java.nio.file.Path;
 import java.nio.file.Paths;
 import java.nio.file.StandardOpenOption;
+import java.util.Map;
 import java.util.concurrent.atomic.AtomicReference;
 
 import org.apache.hadoop.hive.conf.HiveConf;
@@ -90,4 +91,42 @@ void openInternalUnsafe(boolean isAsync, SessionState.LogHelper console) throws
     Assert.assertFalse("Scratch dir is not supposed to exist after cleanup: " + scratchDirPath.get(),
         Files.exists(Paths.get(scratchDirPath.get())));
   }
+
+  /**
+   * Tests whether commonLocalResources is populated with app jar and localized resources when opening
+   * a Tez session.
+   */
+  @Test
+  public void testCommonLocalResourcesPopulatedOnSessionOpen() throws Exception {
+    Path jarPath = Files.createTempFile("test-jar", ".jar");
+    Files.write(jarPath, "testCommonLocalResourcesPopulated".getBytes(), StandardOpenOption.APPEND);
+
+    HiveConf hiveConf = new HiveConfForTest(getClass());
+    hiveConf.set("hive.security.authorization.manager",
+        "org.apache.hadoop.hive.ql.security.authorization.plugin.sqlstd.SQLStdConfOnlyAuthorizerFactory");
+    SessionState.start(hiveConf);
+
+    TezSessionState.HiveResources resources =
+        new TezSessionState.HiveResources(new org.apache.hadoop.fs.Path("/tmp"));
+
+    TezSessionState tempSession = new TezSessionState(SessionState.get().getSessionId(), hiveConf);
+
+    LocalResource localizedLr = tempSession.createJarLocalResource(jarPath.toUri().toString());
+    resources.localizedResources.add(localizedLr);
+
+    final TezSessionState sessionStateForTest = new TezSessionState(SessionState.get().getSessionId(), hiveConf) {
+      @Override
+      void openInternalUnsafe(boolean isAsync, SessionState.LogHelper console) {
+        Map<String, LocalResource> commonLocalResources = buildCommonLocalResources();
+        Assert.assertEquals("commonLocalResources must contain exactly 2 jars (hive-exec app jar + localized test jar)",
+            2, commonLocalResources.size());
+        Assert.assertTrue("commonLocalResources must contain the hive-exec app jar",
+            commonLocalResources.keySet().stream().anyMatch(k -> k.contains("hive-exec")));
+        Assert.assertTrue("commonLocalResources must contain the added localized test jar",
+            commonLocalResources.containsKey(DagUtils.getBaseName(localizedLr)));
+      }
+    };
+
+    sessionStateForTest.open(resources);
+  }
 }