[FLINK-8731] TwoInputStreamTaskTest flaky on travis

• Type: Bug
• Status: Resolved
• Priority: Critical
• Resolution: Fixed
• Affects Version/s: 1.5.0
• Fix Version/s: 1.5.2, 1.6.0
• Component/s: Tests
• Labels: pull-request-available test-stability
• Assignee: Dawid Wysakowicz
• Reporter: Chesnay Schepler
• Created: 21/Feb/18 15:53
• Updated: 28/Feb/19 10:46
• Resolved: 16/Jul/18 12:30

Description

https://travis-ci.org/zentol/flink/builds/344307861

Tests run: 5, Failures: 0, Errors: 1, Skipped: 0, Time elapsed: 2.479 sec <<< FAILURE! - in org.apache.flink.streaming.runtime.tasks.TwoInputStreamTaskTest
testOpenCloseAndTimestamps(org.apache.flink.streaming.runtime.tasks.TwoInputStreamTaskTest)  Time elapsed: 0.05 sec  <<< ERROR!
java.lang.Exception: error in task
	at org.apache.flink.streaming.runtime.tasks.StreamTaskTestHarness.waitForTaskCompletion(StreamTaskTestHarness.java:250)
	at org.apache.flink.streaming.runtime.tasks.StreamTaskTestHarness.waitForTaskCompletion(StreamTaskTestHarness.java:233)
	at org.apache.flink.streaming.runtime.tasks.TwoInputStreamTaskTest.testOpenCloseAndTimestamps(TwoInputStreamTaskTest.java:99)
Caused by: org.mockito.exceptions.misusing.WrongTypeOfReturnValue: 
Boolean cannot be returned by getChannelIndex()
getChannelIndex() should return int
***
If you're unsure why you're getting above error read on.
Due to the nature of the syntax above problem might occur because:
1. This exception *might* occur in wrongly written multi-threaded tests.
   Please refer to Mockito FAQ on limitations of concurrency testing.
2. A spy is stubbed using when(spy.foo()).then() syntax. It is safer to stub spies - 
   - with doReturn|Throw() family of methods. More in javadocs for Mockito.spy() method.

	at org.apache.flink.runtime.io.network.partition.consumer.UnionInputGate.waitAndGetNextInputGate(UnionInputGate.java:212)
	at org.apache.flink.runtime.io.network.partition.consumer.UnionInputGate.getNextBufferOrEvent(UnionInputGate.java:158)
	at org.apache.flink.streaming.runtime.io.BarrierBuffer.getNextNonBlocked(BarrierBuffer.java:164)
	at org.apache.flink.streaming.runtime.io.StreamTwoInputProcessor.processInput(StreamTwoInputProcessor.java:292)
	at org.apache.flink.streaming.runtime.tasks.TwoInputStreamTask.run(TwoInputStreamTask.java:115)
	at org.apache.flink.streaming.runtime.tasks.StreamTask.invoke(StreamTask.java:308)
	at org.apache.flink.streaming.runtime.tasks.StreamTaskTestHarness$TaskThread.run(StreamTaskTestHarness.java:437)

Issue Links

• supercedes: FLINK-9847 OneInputStreamTaskTest.testWatermarksNotForwardedWithinChainWhenIdle unstable
• links to: GitHub Pull Request #6338