--- /dev/null
+var Traverse = require('traverse');
+var assert = require('assert');
+
+exports['negative update test'] = function () {
+ var obj = [ 5, 6, -3, [ 7, 8, -2, 1 ], { f : 10, g : -13 } ];
+ var fixed = Traverse.map(obj, function (x) {
+ if (x < 0) this.update(x + 128);
+ });
+
+ assert.deepEqual(fixed,
+ [ 5, 6, 125, [ 7, 8, 126, 1 ], { f: 10, g: 115 } ],
+ 'Negative values += 128'
+ );
+
+ assert.deepEqual(obj,
+ [ 5, 6, -3, [ 7, 8, -2, 1 ], { f: 10, g: -13 } ],
+ 'Original references not modified'
+ );
+}
+