Depending on the time zone, the TestDocumentDiff test cases can fail on date assertions, for instance:
testDocDiff(org.nuxeo.ecm.diff.service.TestDocumentDiff) Time elapsed: 0.856 sec <<< FAILURE! org.junit.ComparisonFailure: Wrong left value expected:<2011-12-29T1[0]:24:25.00Z> but was:<2011-12-29T1[6]:24:25.00Z>
Let's follow the recommendations from https://doc.nuxeo.com/display/CORG/Writing+tests+working+with+dates