In Visual Studio 2010, I have a number of unit tests. When I run multiple tests at one time using test lists, I sometimes reveive the following error for one or more of the tests:
The agent process was stopped while
the test was running.
It is never the same test failing, and if I try to run the test again, it succeeds.
I found this bug report on Connect, which seems to be the same problem, but it does not offer a solution.
Has anyone else seen this behaviour ? How I can avoid it ?
Edit
I am still experiencing this bug, and so is many of my colleagues on the same software/hardware setup. I have evaluated the answers so far, but they don't resolve the problem. I am starting a bounty for a solution to this problem.
This message is caused by an exception on a thread different from the executing test thread. All answers so far boil down to this simple explanation. It is a known bug in Visual Studio not to display any sensible information in that case.
Visual Studio’s test runner totally chokes if a thread other than the executing test thread throws an exception: It gets swallowed and there’s no output, no chance to intercept and debug and no nothing except a burned-down smoldering mess that was supposed to be your unit test.
I've just experienced the similar problem: some tests fail and they are different in different test runs. I don't know exactly the reason why it happens, but it began to occur when I added a finalizer to one of my classes. When I disable the finalizer - the problem disappears. When I turn the finalizer on - the problem comes back.
Right now I don't know how to overcome this.
I was having this problem, and it turned out to be a problem in my code which the Test Framework wasn't catching properly. A little accidental refactoring had left me with this code:
public void GetThingy()
{
this.GetThingy();
}
This is of course an infinite recursion, and caused a StackOverflowException (I guess). What this caused was the dreaded: "The agent process was stopped while the test was running."
A quick code inspection showed me the problem, and my tests are now running fine. Hope this helps - might be worth inspecting the code looking for issues, or maybe extracting a bit into a console app and checking it works properly there.
I was able to find the source of my problem by looking in the test result file (/TestResults/*.trx) It provided the full details of the exception that occurred in the background thread, and once I resolved that exception the "agent processed stopped..." error went away.
In my case I was unintentionally launching the GUI in my unit test, which eventually caused a System.ComponentModel.InvalidAsynchronousStateException to be thrown.
So my .trx file contained:
<RunInfo computerName="DT-1202" outcome="Error" timestamp="2013-07-29T13:52:11.2647907-04:00">
<Text>One of the background threads threw exception:
System.ComponentModel.InvalidAsynchronousStateException: An error occurred invoking the method. The destination thread no longer exists.
at System.Windows.Forms.Control.WaitForWaitHandle(WaitHandle waitHandle)
at System.Windows.Forms.Control.MarshaledInvoke(Control caller, Delegate method, Object[] args, Boolean synchronous)
at System.Windows.Forms.Control.Invoke(Delegate method, Object[] args)
at System.Windows.Forms.Control.Invoke(Delegate method)
...
</Text>
</RunInfo>
This didn't provide any information on what test caused the error, but it did show me where the exception was, which was very useful.
This message is typically generated when the test process crashes and can happen when there is an unhandled exception on a background thread, a stack overflow occurs, or an explicit call to Process.GetCurrentProcess().Kill() or Environment.Exit. Another possible cause is an access violation in unmanaged code.
Something no one has mentioned is that there may be additional information in the event log. Usually you will not get much information on why the test crashed in the results, however in the event of an unhandled exception on a background thread, then the test framework writes details to the Application event log with source VSTTExecution. If there is no information written to the event log then it is likely one of the other causes listed above.
I encountered the same Problem and solved it while Removing
Environment.Exit(0);
So i am pretty sure, that this error occurs while your test or method under test, is causing the executing process to terminate.
In my case the solution was resolved by checking the Output Window.
'QTAgent32.exe' (Managed
(v4.0.30319)): Loaded
'C:\TestResults\bdewey_XXXXXX072
2011-01-11
17_00_40\Out\MyCode.dll',
Symbols loaded. E, 9024, 9,
2011/01/11, 17:00:46.827,
XXXXX072\QTAgent32.exe, Unhandled
Exception Caught, reporting through
Watson: [Exception message]
In my case I had a FileSystemWatcher that was throwing an error on a seperate thread.
Thanks for posting the question. I just ran into this problem and figured out a cause that you may be running into.
An asynchronous exception may have
occurred
During my test setup, I create an object that queues a worker thread in the thread pool. If I run through debugging fast enough my code passes.
If the worker thread kicks off and has an error BEFORE the test setup completes, then I get a result of Aborted with no reasoning.
If the worker thread kicks off and has an error AFTER the test has begun, then I get a result of : Error - The agent process was stopped while the test was running.
Important to note: this is a component that I use throughout several of my tests. If the test framework encounters too many of these errors it aborts the rest of the tests.
Hope this helps
I added try/catch blocks to the descructor ~ClassName(){} that were defined in any class involved in my tests. This fixed the problem for me.
~MyClass()
{
try
{
// Some Code
}
catch (Exception e)
{
// Log the exception so it's not totally hidden
// Console.WriteLine(e.ToString());
}
}
For finding out where the exception was thrown click on the hyperlink "Test Run Error" next to the exclamation icon in the Test Results window. A window with the stack trace is opened.
This helps a lot to track down the error!
I had the same problem and it was caused by a finalizer for an unmanaged resource (a file writer that was not getting disposed properly for some reason).
After wrapping the finalizer code in a try-catch that swallows the exception, the problem disappeared. I don't recommend swallowing exceptions like that, so it would obviously be wise to find out why the exception is occurring in the first place.
I have had this happening on the odd occasion, and the culprit almost always turns out to be threading.
Strangely enough all the tests would work fine on the development machines, then randomly fail on the build servers.
On closer inspection it turned out that although the tests were being listed as passed on the dev boxes, there were exceptions being thrown. The exceptions were being thrown on a seperate thread which didn't get picked up as an error.
The exception details were being logged against the test trace, so we were able to identify which code/tests needed to be modified.
Hope this helps someone.
In my case I had some unit-tests for a WCF-service. This WCF service was starting up 2 timers.
Those timers caused side effects.
--> I disable these timers by default and everything is fine!
BTW: I use WCFMock to fake the WCF service, so I have "real" unit tests around my WCF service
This error was caused by a Finalizer for me as well.
The Finalizer was actaully calling some DB code which wasn't mocked out. Took me a while to find it as it wasn't a class I wrote and the reference to it was burred quite a few classes deep.
I have run into a similar problem where a test is failing in TestInitialize and is also running code from a ddl from another of my projects. I get the error message as described above and if I try to debug the test, the test is just aborted without any exception details.
I suspect that the problem may be that the dlls from my other project are from a Visual Studio 2012 project and I am running my tests in a VS2010 project, and/or possibly that the UnitTestFramwork dll versions from the 2 projects are mismatched.
The problem can also be triggered by an Exception or Stackoverflow in Constructor of a TestClass.
As this error can have many different causes, I'd like to add another one for completeness of this thread.
If all your tests are aborting as described by the OP, the cause might be a wrong project configuration. In my case the target framework was set to .NET Framework 3.5. Setting it to a higher version through the project properties page (tab Application) resolved the issue.
I was able to determine what was causing my issue by looking in the Windows Logs > Application log entries within the Windows Event Viewer. Look for entries at the time the test bombed-out. I had an Error entry similar to below:
QTAgent32_40.exe, PID 10432, Thread 2) AgentProcess:CurrentDomain_UnhandledException: IsTerminating : System.NullReferenceException: Object reference not set to an instance of an object.
at XXX.YYY.ZZZ.cs:line 660
at XXX.YYY.AAA.Finalize() in C:\JenkinsSlave\workspace\XXX.YYY.AAA.cs:line 180
It was indeed a null reference exception within a method called from a class finalizer.
For anyone happening upon this old question and wondering what's being thrown from their thread(s), here's a tip. Using Task.Run (as opposed to, say, Thread.Start) will report child thread exceptions much more reliably. In short, instead of this:
Thread t = new Thread(FunctionThatThrows);
t.Start();
t.Join();
Do this:
Task t = Task.Run(() => FunctionThatThrows());
t.Wait();
And your error logs should be much more useful.
Related
Fellow experts!
I have faced the following dilemma: some of our tools (executables) are started as scheduled tasks, some are started as services and others as usual desktop apps with interactive Windows user. We are using the code sharing strategy for source management (this is not debatable for this question).
So the solution I want to find is the following:
Detect UI operation at run-time which leads to hanging service/background task (such as say call to Application.ShowException, ShowMessage, MessageDialog, TForm.Show etc.). And when such an action detected I want to raise the exception instead. Then the operation will fail, we will have stack trace etc. but the process will not hang up! The most problematic hang up is when some event processing is done in transaction and then in some of the code used to process event suddenly (because of error in code, design, whatever) there is UI code executed then the process hangs and the DB parts can be locked!
What I think I need to do is: Use DDetours library to intercept WinAPI calls to a certain routines and raise exception instead (so that the process does not hang, but just fail in some method). Also I know that the creation of forms and windows does not hang the app, but only the tries to show them to the user.
Is there some known method of handling this problem? Or maybe there is some list of WinAPI routine set which hangs in service mode?
Thank you in advance.
I've been using HP UFT for a couple of years now and I needed to start scheduling my tests to run during the night which I've sort of managed but I'm getting a few errors when the tests run, usually a 'Retry' will continue the test, it may be that the web site is not rendering quick enough for the next line of code. Sometimes it will fail randomly, again a retry will work (where I haven't already added a sync point)
So I could do with an 'on error retry', does such a thing exist? or could someone advise if there is a way around this please? perhaps a screenshot of the error would also be helpful so I know where my test is falling over and I can add a sync point or a wait.
Edit: Apologies for not giving enough info..
The error is an application error, and a pretty generic one where UFT cannot find the object to click on e.g.
"Cannot find the 'xxx' objects parent class frame, verify the parent properties match an object currently displayed in your application."
when this error appears I get options to 'Stop', 'RETRY', 'Skip' or 'Debug'
Given that you've (Pranav - Thanks) said 'on error retry' doesn't exist then you've pretty much answered my question, the only other way I can think to get around this is to keep running the tests and add sync points each time I get a problem and hopefully it will bottom out and ease off.
I will also look at recovery scenarios thanks Dave.
Create a Scenario Recovery for the test
Resources > Scenario Recovery
Create a scenario for Test run Error, this report the test as failed and include the error message in the run report. Allowing your other tests to keep going.
It also has Post-recovery options that "retry the current step and continue".
Tuorialspoint.com have a helpful reference
Recovery scenario reduces the need to add a check point after most lines of code :) thanks UFT.
I'm creating a Fitnesse slim test (Decision Table). In order to run the test I need to start my Spring app. context. For that, I'm using a class that extends FixtureWirer. Starting the application context is not a problem, since the test completes successfully. In the page I can see that the test is complete and all the output values are compared. The problem is that the page with the final results never stops loading, but no exception is thrown. And that only happens when I use the FixtureWirer to start the application context, so I'm guessing the problem is related to that, but I haven't been able to figure it out.
Thanks in advance.
Do you mean the test doesn't stop as it is supposed to? If so, can you try to close the context
This may be because your Spring's shut down hook, is not being able to destroy beans which must
be blocked by any resource.
Can you check if there are any live threads after the execution of test that are blocked?
If there are any live threads left then Slim server would not terminate (SlimServer java process will not be killed).
i'm developing a multi-platform C++ fuzzing application. The app spawns a child process and checks whether it stopped unexpectedly. I've already managed to do this on linux, however, windows exception handling mechanism is making things hard for me.
My code right now does the following:
- Call CreateProcess to spawn the process.
- WaitForSingleObject to wait for it to terminate.
- Then call GetExitCodeProcess and check if the exit code corresponds to an exception.
Everything works as it should, i've tested it with a null dereferencing test application, and i can catch the exception gracefully. However, each time i test this, a Windows error message box spawns telling me to Send or Not Send the error report. Since the fuzzer is supposed to be an automatic testing application, i'd need to somehow disable this notification, so that even if an exception is caught, the fuzzer can continue testing.
I've already tried installing a SEH handler, but had no luck(apparently these handlers aren't inherited by child processes). I've read something about using vectored exception handling, but suppose it would be the same, i believe vector handlers aren't inherited.
Could anybody help me with this problem? I don't know what to search for, i've already googled a lot and haven't found anyhing.
Thanks!
Debug API is one option. Here is a starting point in MSDN.
Following on frast's answer, you can spawn the process as a child of a process with a suitable SetErrorMode. This (inheritable) setting determines which errors will result in dialogs popping out - I found your question while trying to achieve the exact same thing for an automated testing application.
To avoid any error dialogs, use
SetErrorMode(
SEM_FAILCRITICALERRORS
| SEM_NOALIGNMENTFAULTEXCEPT
| SEM_NOGPFAULTERRORBOX
| SEM_NOOPENFILEERRORBOX);
Injection is probably overkill - better to use a wrapper process.
Try to inject the following code into your child process:
SetErrorMode(SEM_NOGPFAULTERRORBOX);
Lookup the details of SetErrorMode in MSDN.
Read about injection technique here:
Injective Code inside Import Table
We are running our Junit 4 test suite against Weblogic 9 in front of an Oracle 10 database (using Hudson as a continuous integration server) and occasionally we will get an ORA-12519 crash during script teardown. However, the error is very intermittent:
It usually happens for the same Test class
It doesn't always happen for the same test cases (sometimes they pass)
It doesn't happen for the same number of test cases (anywhere from 3-9)
Sometimes it doesn't happen at all, everything passes
While I can't guarantee this doesn't happen locally (when running against the same database, of course), I have run the same suite of class multiple times with no issues.
Any ideas?
Don't know if this will be everybody's answer, but after some digging, here's what we came up with.
The error is obviously caused by the fact that the listener was not accepting connections, but why would we get that error when other tests could connect fine (we could also connect no problem through sqlplus)? The key to the issue wasn't that we couldn't connect, but that it was intermittent
After some investigation, we found that there was some static data created during the class setup that would keep open connections for the life of the test class, creating new ones as it went. Now, even though all of the resources were properly released when this class went out of scope (via a finally{} block, of course), there were some cases during the run when this class would swallow up all available connections (okay, bad practice alert - this was unit test code that connected directly rather than using a pool, so the same problem could not happen in production).
The fix was to not make that class static and run in the class setup, but instead use it in the per method setUp and tearDown methods.
So if you get this error in your own apps, slap a profiler on that bad boy and see if you might have a connection leak. Hope that helps.
Another solution I have found to a similar error but the same error message is to increase the number of service handlers found. (My instance of this error was caused by too many connections in the Weblogic Portal Connection pools.)
Run SQL*Plus and login as SYSTEM. You should know what password you’ve used during the installation of Oracle DB XE.
Run the command alter system set processes=150 scope=spfile; in SQL*Plus OR any SQL friendly IDE.
VERY IMPORTANT: Restart the database, to make the change effective in the SPFILE.
From here:
http://www.atpeaz.com/index.php/2010/fixing-the-ora-12519-tnsno-appropriate-service-handler-found-error/
I also had the same problem, I searched for the answers many places. I got many similar answers to change the number of process/service handlers. But I thought, what if I forgot to reset it back?
Then I tried using Thread.sleep() method after each of my connection.close();.
I don't know how, but it's working at least for me.
If any one wants to try it out and figure out how it's working then please go ahead. I would also like to know it as I am a beginner in programming world.
I had this problem in a unit test which opened a lot of connections to the DB via a connection pool and then "stopped" the connection pool (ManagedDataSource actually) to release the connections at the end of the each test. I always ran out of connections at some point in the suite of tests.
Added a Thread.sleep(500) in the teardown() of my tests and this resolved the issue. I think that what was happening was that the connection pool stop() releases the active connections in another thread so that if the main thread keeps running tests the cleanup thread(s) got so far behind that the Oracle server ran out of connections. Adding the sleep allows the background threads to release the pooled connections.
This is much less of an issue in the real world because the DB servers are much bigger and there is a healthy mix of operations (not just endless DB connect/disconnect operations).
I had the similar issue. It happened every time when I run a pack of database (Spring JDBC) tests with SpringJUnit4ClassRunner, so I resolved the issue putting #DirtiesContext annotation for each test in order to cleanup the application context and release all resources thus each test could run with a new initalization of the application context.