You can clone with
Sometimes, when strings are mutated, the resulting code can't be diffed.
Instead, you end up with
The following mutations didn't cause test failures:
Binary files original and mutation differ
Unfortunately, I can't easily reproduce this issue because the mutations are pseudo-random, and you can't pass a seed into the Heckle executable.
$ uname -a
Linux [redacted] 3.2.0-33-generic #52-Ubuntu SMP Thu Oct 18 16:29:15 UTC 2012 x86_64 x86_64 x86_64 GNU/Linux
$ ruby1.9.1 --version
ruby 1.9.3p0 (2011-10-30 revision 33570) [x86_64-linux]
Ew. yeah. we should diff with -a. :(