skip returning tests in emulator

google-cloud-spanner/src/test/java/com/google/cloud/spanner/connection/it/ITDmlReturningTest.java

@@ -22,6 +22,7 @@
 import static org.junit.Assert.assertNotNull;
 import static org.junit.Assert.assertThrows;
 import static org.junit.Assert.assertTrue;
+import static org.junit.Assume.assumeFalse;
 
 import com.google.cloud.spanner.AsyncResultSet;
 import com.google.cloud.spanner.AsyncResultSet.CallbackResponse;
@@ -38,6 +39,7 @@
 import com.google.cloud.spanner.connection.StatementResult;
 import com.google.cloud.spanner.connection.StatementResult.ResultType;
 import com.google.cloud.spanner.connection.TransactionMode;
+import com.google.cloud.spanner.testing.EmulatorSpannerHelper;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableMap;
 import java.util.ArrayList;
@@ -49,6 +51,7 @@
 import java.util.concurrent.ExecutionException;
 import java.util.concurrent.Executors;
 import org.junit.Before;
+import org.junit.BeforeClass;
 import org.junit.Test;
 import org.junit.experimental.categories.Category;
 import org.junit.runner.RunWith;
@@ -107,6 +110,8 @@ private boolean checkAndSetInitialized() {
 
   @Before
   public void setupTable() {
+    assumeFalse(
+        "DML Returning is not supported in the emulator", EmulatorSpannerHelper.isUsingEmulator());
     if (checkAndSetInitialized()) {
       database =
           env.getTestHelper()