These cover some of the possible errors with delta fragments. Many of
the same tests could be implemented slightly easier by testing the
helper functions, but the infrastructure is already set up to test the
full function.
This is made easier by the bin.go CLI, which can parse and encode binary
patch data. Once parsed, fragments were manipulated with truncate and
dd, encoded, and placed in the patch files.
Covers basic literal and delta application. Input files were created by
using dd and the 'conv=notrunc' option to modify sections of files
created from /dev/urandom. All file start with two null bytes to
convince Git they are binary.