#1 Test fails should be reported as soon as possible.

[Dmitry Y. Kazarov]

Many tests depends on successfull passing of previous
tests (for example, i test most simple functions first,
then functions that use those simple funcitons), so
when test fails other test results becomes unpredictable.
And test failure should be reported (printed) as soon as
possible.

In my case incorrect work of hash function leaded to
endless loop in next test. If first failure would be
reported I had not needed to launch debugger.

Dmitry