[erlang-questions] rebar eunit test pass but fail on cover test

[ruanbeihong]

Hi everyone,

I'm learning erlang  for a while. Currently I'm using rebar 
to manage building and test work. I find the cover test 
provided in rebar (eunit?) quite convenient.

But recently I come across a strange situation: when running 
test without '{cover_enabled, true}.' in rebar.conf, it 
works find and passed my test, but with it will result in a 
fail of test. And the crush info is IMO not quite useful.

So I ask here for someone might come across same problem and 
to see if this is a bug.

My code is at  https://github.com/jamesruan/z85
commit: 6e0fc13667
simply git clone it and run:
  rebar eunit
or
  rebar -C rebar.conf eunit
The first will success in my environment (
Erlang/OTP 18 [erts-7.0] [source] [64-bit] [smp:4:4] [async-
threads:10] [kernel-poll:false])
But the second will fail.

Thanks,

James Ruan