/**

 * js increment operators (ob.prop += ob2.prop) do not work, after assigment like this ob = ob2.pop()

 *

 * @link https://jira.mongodb.org/browse/@TODO

 *

 * Affected versions:		r2.1.0-1580-g0c1a6bd (v8)

 * 					v8 engine: Version 3.9.23

 *

 * Not affected versions:	2.0.3-1 (spider monkey)

 */

var testCollName = 'such-collection-can-t-exist';

var testColl = db.getCollection(testCollName);

testColl.insert({key: 1, foo: 1});

testColl.insert({key: 1, foo: 1});

testColl.insert({key: 1, foo: 1});

res = db.runCommand({

	mapreduce: testCollName,

	map: function() {

		emit(this.key, {foo: this.foo});

	},

	reduce: function(k, vals) {

		var result = vals.pop();

		for (i in vals) {

			result.foo += vals[i].foo;

			assert(result.foo > 1, " must be :: > 1");

		}

		return result;

	},

	out: {inline: 1}, // the same with "replace" and others

});

printjson(res);

testColl.drop();

var arrayOfObjects = [];

arrayOfObjects.push({key: 1, foo: 1});

arrayOfObjects.push({key: 1, foo: 1});

arrayOfObjects.push({key: 1, foo: 1});

object = arrayOfObjects.pop();

for (i in arrayOfObjects) {

	object.foo += arrayOfObjects[i].foo;

}

assert(object.foo > 1);

db.eval(function() {

	var arrayOfObjects = [];

	arrayOfObjects.push({key: 1, foo: 1});

	arrayOfObjects.push({key: 1, foo: 1});

	arrayOfObjects.push({key: 1, foo: 1});

	object = arrayOfObjects.pop();

	for (i in arrayOfObjects) {

		object.foo += arrayOfObjects[i].foo;

	}

	assert(object.foo > 1);