[Swan-dev] diff -w et.al. are very very blunt tools

[Andrew Cagney]

So way back when,  libreswan=testsuite had two characteristics:

- libreswan contained many white space bugs and regressions were
consistently ignored
- diff -w was being used

now we have:

- libreswan contains far fewer white space bugs and doesn't regress
- diff without -w is being used

(the exception would be blank lines where the sanitizer, unhelpfully,
deletes them)

Perhaps I'm going out on a limb, but I suspect all this isn't just a
coincidence.

However, this isn't perfect - tools libreswan doesn't control, such as
'strongswan' and 'ip', still cause problems.   For those we do need a
way to be more forgiving, but not at the expense of ignoring white
space bugs in libreswan.

My hunch is that for these tools we should be using narrow tool
specific sanitizers like:

'/^ TOOL .../,/^[a-z]* #/ {
  ... tool specific substitutions ...
}

so that only that tools output is mangled.

Andrew