When I run this at the command line, the exit code seems to be 0:
% echo 'error()' | julia && echo pass 
ERROR: 
Stacktrace:
 [1] error()
   @ Base ./error.jl:44
 [2] top-level scope
   @ none:1
pass
%
In contrast, grep does just fine
% echo 'error()' | grep f && echo pass
%