[Internal] Allow interrupt for already interrupted transaction (#1397)

Author: injectives

driver/src/main/java/org/neo4j/driver/internal/async/UnmanagedTransaction.java

@@ -179,7 +179,7 @@ public boolean isOpen() {
     public void markTerminated(Throwable cause) {
         executeWithLock(lock, () -> {
             if (state == State.TERMINATED) {
-                if (causeOfTermination != null) {
+                if (causeOfTermination != null && cause != null) {
                     addSuppressedWhenNotCaptured(causeOfTermination, cause);
                 }
             } else {

driver/src/test/java/org/neo4j/driver/internal/async/UnmanagedTransactionTest.java

@@ -43,6 +43,7 @@
 import static org.neo4j.driver.testutil.TestUtil.await;
 import static org.neo4j.driver.testutil.TestUtil.beginMessage;
 import static org.neo4j.driver.testutil.TestUtil.connectionMock;
+import static org.neo4j.driver.testutil.TestUtil.setupFailingRun;
 import static org.neo4j.driver.testutil.TestUtil.setupSuccessfulRunAndPull;
 import static org.neo4j.driver.testutil.TestUtil.setupSuccessfulRunRx;
 import static org.neo4j.driver.testutil.TestUtil.verifyBeginTx;
@@ -69,6 +70,7 @@
 import org.neo4j.driver.exceptions.AuthorizationExpiredException;
 import org.neo4j.driver.exceptions.ClientException;
 import org.neo4j.driver.exceptions.ConnectionReadTimeoutException;
+import org.neo4j.driver.exceptions.Neo4jException;
 import org.neo4j.driver.internal.FailableCursor;
 import org.neo4j.driver.internal.InternalBookmark;
 import org.neo4j.driver.internal.messaging.BoltProtocol;
@@ -456,6 +458,27 @@ void shouldServeTheSameStageOnInterruptAsync() {
         assertEquals(stage0, stage1);
     }
 
+    @Test
+    void shouldHandleInterruptionWhenAlreadyInterrupted() throws ExecutionException, InterruptedException {
+        // Given
+        var connection = connectionMock(BoltProtocolV4.INSTANCE);
+        var exception = new Neo4jException("message");
+        setupFailingRun(connection, exception);
+        var tx = beginTx(connection);
+        Throwable actualException = null;
+
+        // When
+        try {
+            tx.runAsync(new Query("RETURN 1")).toCompletableFuture().get();
+        } catch (ExecutionException e) {
+            actualException = e.getCause();
+        }
+        tx.interruptAsync().toCompletableFuture().get();
+
+        // Then
+        assertEquals(exception, actualException);
+    }
+
     private static UnmanagedTransaction beginTx(Connection connection) {
         return beginTx(connection, Collections.emptySet());
     }