view contrib/plan9/9diff @ 45111:7528699c6ccb

rust-status: refactor status into a struct

The code for `dirstate/status` has grown too large for comfort, this is the
first of three patches that try to improve maintainability.
In this patch, refactoring dirstate's status into a struct allows for slimming
down function signatures drastically, keeping the mental (and maintenance)
burden lower, since pretty much all of them shared a few common arguments.

This had the pleasant side-effect of simplifying lifetimes a little. This has
no observable impact on performance.

The next patch will add/improve documentation and refactor some types. I tried
to keep new code down to a minimum in this patch because it's already pretty
big.

Differential Revision: https://phab.mercurial-scm.org/D8661

#!/bin/rc
# 9diff - Mercurial extdiff wrapper for diff(1)

rfork e

fn getfiles {
	cd $1 &&
	for(f in `{du -as | awk '{print $2}'})
		test -f $f && echo `{cleanname $f}
}

fn usage {
	echo >[1=2] usage: 9diff [diff options] parent child root
	exit usage
}

opts=()
while(~ $1 -*){
	opts=($opts $1)
	shift
}
if(! ~ $#* 3)
	usage

# extdiff will set the parent and child to a single file if there is
# only one change. If there are multiple changes, directories will be
# set. diff(1) does not cope particularly with directories; instead we
# do the recursion ourselves and diff each file individually.
if(test -f $1)
	diff $opts $1 $2
if not{
	# extdiff will create a snapshot of the working copy to prevent
	# conflicts during the diff. We circumvent this behavior by
	# diffing against the repository root to produce plumbable
	# output. This is antisocial.
	for(f in `{sort -u <{getfiles $1} <{getfiles $2}}){
		file1=$1/$f; test -f $file1 || file1=/dev/null
		file2=$3/$f; test -f $file2 || file2=/dev/null
		diff $opts $file1 $file2
	}
}
exit ''