Computed, have an issue when sorting

[Miguelrn]

Version

2.5.17-beta.0

Reproduction link

https://jsfiddle.net/Pomer/vdq3wbtL/1/

Steps to reproduce

Simple you can change Vue from 2.5.17 to 2.5.17-beta and the jsfiddle will stop working.
The idea it's simple we have an array of json componen than need to be sorted via computed function.

What is expected?

array of elements sorted, instead we get an error and nothing shown.

What is actually happening?

It seems to have an infinite loop, since i can set a console.log before the return statement of the computed function and see how many times its been called this function.

---

stacktrace:

vue.js:597 [Vue warn]: Error in render: "RangeError: Maximum call stack size exceeded"
(found` in <Root>)
warn @ vue.js:597
logError @ vue.js:1740
globalHandleError @ vue.js:1735
handleError @ vue.js:1724
Vue._render @ vue.js:4562
updateComponent @ vue.js:2779
get @ vue.js:3144
Watcher @ vue.js:3132
mountComponent @ vue.js:2786
Vue.$mount @ vue.js:8557
Vue.$mount @ vue.js:10957
Vue._init @ vue.js:4652
Vue @ vue.js:4739
(anonymous) @ main.js:9
vue.js:1744 RangeError: Maximum call stack size exceeded   
    at Watcher.get (vue.js:3158)
    at Watcher.getAndInvoke (vue.js:3244)
    at Watcher.update (vue.js:3222)
    at Dep.notify (vue.js:703)
    at Array.mutator (vue.js:851)
    at Vue.testSort (main.js:89)
    at Watcher.get (vue.js:3144)
    at Watcher.getAndInvoke (vue.js:3244)
    at Watcher.update (vue.js:3222)
    at Dep.notify (vue.js:703)

[posva]

This is probably related to #8446, closing as a duplicate

However, sort modifies the original array, you should create a new one with slice() first and it will work