svn commit: r360125 - in head/usr.bin/diff: . tests

[Jan Beich]

Kyle Evans <kevans at FreeBSD.org> writes:

> Author: kevans
> Date: Mon Apr 20 16:14:44 2020
> New Revision: 360125
> URL: https://svnweb.freebsd.org/changeset/base/360125
>
> Log:
>   diff(1): reject conflicting formatting options
>   
>   This matches GNU diff(1) behavior and, more importantly, eliminates any
>   source of confusion if multiple formatting options are specified.
>   
>   Note that the committed diff differs slightly from the submitted: I've
>   modified it so that we initialize diff_format to something that isn't an
>   accepted format option so that we can also reject --normal -c and -c
>   --normal, which would've otherwise been accepted because the default was
>   --normal. After option parsing we default it to D_NORMAL if it's still
>   unset.
>   
>   PR:		243975
>   Submitted by:	fehmi noyan isi
>   MFC after:	1 week

Appears to break ability to specify number of context lines e.g.,

$ diff -U999 /usr/include/sha256.h /usr/include/sha512.h
error: conflicting output format options.
usage: diff [-aBbdilpTtw] [-c | -e | -f | -n | -q | -u] [--ignore-case]
[...]