Github user weijietong commented on the issue:
https://github.com/apache/drill/pull/904
@vvysotskyi the problem with mocking strategy is that when I run the test
case just with the single method `testToDateForTimeStamp` it will pass. but
when I run the whole test cases of the `TestCastFunctions ` , the included
`testToDateForTimeStamp` method will fail.---
