view contrib/plan9/9mail @ 36673:b3c9c483cac9

xdiff: add a bdiff hunk mode

xdiff generated hunks for the differences (ex. questionmarks in the
`@@ -?,?  +?,? @@` part from `diff --git` output). However, bdiff generates
matched hunks instead.

This patch adds a `XDL_EMIT_BDIFFHUNK` flag used by the output function
`xdl_call_hunk_func`.  Once set, xdiff will generate bdiff-like hunks
instead. That makes it easier to use xdiff as a drop-in replacement of bdiff.

Note that since `bdiff('', '')` returns `[(0, 0, 0, 0)]`, the shortcut path
`if (xscr)` is removed. I have checked functions called with `xscr` argument
(`xdl_mark_ignorable`, `xdl_call_hunk_func`, `xdl_emit_diff`,
`xdl_free_script`) work just fine with `xscr = NULL`.

Test Plan:
Will be tested in a later patch.

Differential Revision: https://phab.mercurial-scm.org/D2575

#!/bin/rc
# 9mail - Mercurial email wrapper for upas/marshal

fn usage {
	echo >[1=2] usage: mercurial/9mail -f from to [cc]
	exit usage
}

from=()
cc=()
to=()

switch($1){
case -f
	from=$2
case *
	usage
}

to=($3)
if(~ $#* 4)
	cc=(-C $4)

upasname=$from
upas/marshal $cc $to