🚀 go-pugleaf

GNU diff version 1.12 exits with wrong status when -B flag is used.

For example, if the file a contains just newlines, 

	diff -B a /dev/null

exits with status 1, even though no differences are printed.

In file analyze.c, in the function diff_2_files, an assumption is made that
'script' will be null if there are no significant differences between the two
files.  It is possible however that the script consists entirely of change
nodes with all inserted and deleted fields equal to 0.  In this case, the
function should return 0.