OPM/opm-core — pull request #85 by bska (2012-10-24 22:23:28+00:00)
Title: Don't use '==' when '=' is equally good

There is no need to use Bash-specific operators when the pure sh(1)
built-in test operators have the exact same semantics. This increases
portability to systems for which /bin/sh is *not* Bash (or Dash).