The Tor Browser / file revision

 // |reftest| skip-if(!xulRuntime.shell)

 // bug 905774

 // Proxy options

 var opts = new Proxy({loc: false}, {});

 assertEq(Reflect.parse("0;", opts).loc === null, true);

 opts.loc = true;

 assertEq(Reflect.parse("0;", opts).loc !== null, true);

 delete opts.loc;

 assertEq(Reflect.parse("0;", opts).loc !== null, true);  // default is true

 // Proxy builder

 var builder = {

     program: function (body) { return body.join(); },

     expressionStatement: function (expr) { return expr + ";" },

     literal: function (val) { return "" + val; }

 };

 opts = {builder: new Proxy(builder, {})};

 assertEq(Reflect.parse("0xff;", opts), "255;");

 reportCompare(0, 0, 'ok');