source: drbl_ui/backup/test_busybox/busybox-1.7.2/testsuite/TODO @ 165

This testsuite is quite obviously a work in progress.  As such,
there are a number of good extensions.  If you are looking for
something to do, feel free to tackle one or more of the following:

Moving to the new format.
  The old way was "lots of little tests files in a directory", which
  doesn't interact well with source control systems.  The new test
  format is command.tests files that use testing.sh.

Every busybox applet needs a corresponding applet.tests.

Full SUSv3 test suite.
  Let's make the Linux Test Project jealous, shall we?  Don't just
  audit programs for standards compliance, _prove_ it with a regression
  test harness.

  http://www.opengroup.org/onlinepubs/009695399/utilities/

Some tests need root access.
  It's hard to test things like mount or init as a normal user.
  Possibly User Mode Linux could be used for this, or perhaps
  Erik's buildroot.

libbb unit testing
  Being able to test the functions of libbb individually may
  help to prevent regressions.