jiff/lib/inverse.js

JSON diff and patch based on rfc6902

var patches = require('./patches');

module.exports = function inverse(p) {
	var pr = [];
	var i, skip;
	for(i = p.length-1; i>= 0; i -= skip) {
		skip = invertOp(pr, p[i], i, p);
	}

	return pr;
};

function invertOp(patch, c, i, context) {
	var op = patches[c.op];
	return op !== void 0 && typeof op.inverse === 'function'
		? op.inverse(patch, c, i, context)
		: 1;
}