Final Exercise in Shell Line/Command section Very Challenging-not solvable without external reference?

[juliebates]

Is this solvable without referring to external materials? I found these very challenging, and did not solve, which is still bugging me, Tetris might have helped recharge my brain.

Exercise
Choose shunit2 or bats (or both) and

re-write above test for 1dsum using one of the frameworks. If you do not have AFNI available, you could test generic bc or dc command line calculators possibly available on your system.
Add additional tests to “document” behavior of 1dsum whenever
    input file is empty
    multiple files are provided
    some values are negative