RFR: 8258057: serviceability/attach/RemovingUnixDomainSocketTest.java doesn't ignore VM warnings

[David Holmes]

On 15/12/2020 10:01 am, Alex Menkov wrote:
> On Fri, 11 Dec 2020 17:25:33 GMT, Patricio Chilano Mateo <pchilanomate at openjdk.org> wrote:
> 
>> Hi,
>>
>> Please review the following small fix for test RemovingUnixDomainSocketTest.java. As explained in the bug comments, the issue is due to having two different StreamPumper objects consuming from the same stderr, one created by ProcessTools.startProcess() and another by OutputAnalyzer(). In the failing cases the StreamPumper processing thread created in ProcessTools.startProcess() consumes the first part of the deprecation message while the one created in OutputAnalyzer consumes the rest. Since out.getStderr() is not empty and does not contain the string "VM warning:", the test fails.
>>
>> I simply replaced the ProcessTools.startProcess() call by a call to start() on the ProcessBuilder object, which doesn't use StreamPumper. I added stderrShouldBeEmptyIgnoreDeprecatedWarnings(), since as mentioned in 8248162 we might not want to hide all warning messages.
>>
>> Without the patch I can consistently reproduce the issue. With the patch the test always passes.
>>
>> Thanks,
>> Patricio
> 
> Changes requested by amenkov (Reviewer).
> 
> test/hotspot/jtreg/serviceability/attach/RemovingUnixDomainSocketTest.java line 70:
> 
>> 68:
>> 69:         out.shouldHaveExitValue(0);
>> 70:         out.stderrShouldBeEmptyIgnoreDeprecatedWarnings();
> 
> Looked at the fix one more time.
> 
> I suppose this new method is not needed as a the message about deprecation is VM warning and should be handled by stderrShouldBeEmptyIgnoreVMWarnings.
> Also this new method will fails if jcmd prints some other VM warning

I think that is the point of the new method. We know deprecation 
warnings are harmless and can be ignored. But other warnings may 
indicate an issue that needs investigating.

Cheers,
David

> -------------
> 
> PR: https://git.openjdk.java.net/jdk/pull/1749
>