Add caller stack information in test

TestRequestSender now shows caller stack when operation failed.

Previously, when operation failed, the output only showed operation response
failure. It didn't show any information about where the call has originated.

In this change, the caller stack information is displayed as primary
stacktrace and the failure response stack is showed in suppressed exception
stacktrace.
For "sendAndWaitFailure", when operation was successful, the displayed
exception is now the caller stack information.

Operation failure log:

Before:

  ..IllegalAccessError: forbidden

    at ..Operation.fail(Operation.java:1102)
    at ..ServiceHost.loadServiceState(ServiceHost.java:2567)
    ....

New:

  ..RuntimeException: Received Failure response. (See suppressed exception for detail)

    at ..TestRequestSender.sendAndWait(TestRequestSender.java:192)
    at ..TestRequestSender.sendAndWait(TestRequestSender.java:175)
    at ..TestExampleWithMultiNode.authentication(TestExampleWithMultiNode.java:257)
    ...
    Suppressed: java.lang.IllegalAccessError: forbidden
      at ..Operation.fail(Operation.java:1102)
      at ..loadServiceState(ServiceHost.java:2567)
      ...

https://www.pivotaltracker.com/story/show/127395667

Change-Id: I3c860695f25df659067f4233cc9f48023eeb0eca

xenon-common/src/test/java/com/vmware/xenon/common/test/TestRequestSender.java

@@ -105,7 +105,7 @@ public <T extends ServiceDocument> T sendAndWait(Operation op, Class<T> bodyType
      * Expecting all {@link Operation} to be successful.
      * The order of result corresponds to the input order.
      *
-     * @param ops       operations to perform
+     * @param ops      operations to perform
      * @param bodyType returned body type
      * @param <T>      ServiceDocument
      * @return body documents
@@ -150,13 +150,20 @@ public List<Operation> sendAndWait(List<Operation> ops) {
     public List<Operation> sendAndWait(List<Operation> ops, boolean checkResponse) {
         Operation[] response = new Operation[ops.size()];
 
+        // Keep caller stack information for operation failure.
+        // Actual operation failure will be added to this exception as suppressed exception.
+        // This way, it'll display the original caller location in stacktrace
+        String callerStackMessage = "Received Failure response. (See suppressed exception for detail)";
+        Exception callerStack = new RuntimeException(callerStackMessage);
+
         TestContext waitContext = new TestContext(ops.size(), this.timeout);
         for (int i = 0; i < ops.size(); i++) {
             int index = i;
             Operation op = ops.get(i);
             op.appendCompletion((o, e) -> {
                 if (e != null && checkResponse) {
-                    waitContext.fail(e);
+                    callerStack.addSuppressed(e);
+                    waitContext.fail(callerStack);
                     return;
                 }
                 response[index] = o;
@@ -209,6 +216,10 @@ public <T extends ServiceDocument> T sendPostAndWait(String url, Class<T> bodyTy
     public FailureResponse sendAndWaitFailure(Operation op) {
         FailureResponse response = new FailureResponse();
 
+        // Prepare caller stack information for operation success.
+        String msg = String.format("Expected operation failure but was successful. uri=%s ", op.getUri());
+        Exception callerStack = new RuntimeException(msg);
+
         TestContext waitContext = new TestContext(1, this.timeout);
         op.appendCompletion((o, e) -> {
             if (e != null) {
@@ -217,8 +228,7 @@ public FailureResponse sendAndWaitFailure(Operation op) {
                 waitContext.complete();
                 return;
             }
-            String msg = String.format("Expected operation failure but was successful. uri=%s", o.getUri());
-            waitContext.fail(new RuntimeException(msg));
+            waitContext.fail(callerStack);
         });
         sendRequest(op);
         waitContext.await();

xenon-common/src/test/java/com/vmware/xenon/common/test/VerificationHost.java

@@ -684,7 +684,13 @@ public URI createQueryTaskService(URI factoryUri, QueryTask create, boolean forc
                 create.querySpec.options,
                 create.querySpec.resultLimit);
 
-        QueryTask result = this.sender.sendAndWait(startPost, QueryTask.class);
+        QueryTask result;
+        try {
+            result = this.sender.sendAndWait(startPost, QueryTask.class);
+        } catch (RuntimeException e) {
+            // throw original exception
+            throw ExceptionTestUtils.throwAsUnchecked(e.getSuppressed()[0]);
+        }
 
         if (isDirect) {
             taskResult.results = result.results;