Event handlers in capturing mode won't be removed

[KingMario]

Vue.js version

2.1.3

Reproduction Link

http://codepen.io/KingMario/pen/yVzvoR?editors=0011
From the code pen, you can see that the handler is registered again and again and again without being removed.

What is Expected?

The second h function in the ternary statement returns a new DOM tree will remove the click event handler registered in the first h function.

What is actually happening?

The click event handler is not removed.

Bug Fixed?

According to MDN,

Removal of a capturing listener does not affect a non-capturing version of the same listener, and vice versa.

The bug is fixed in 4th commit of this PR, so please review it or tell me to split it into another PR.

[KingMario]

@sqal

Vue CAN differentiate them.

It's only the problem that registered event handlers in capturing mode should be removed the same mode.

Meanwhile, you can treat this issue as a new feature of rendering function enhancement. Since, currently, events like '!click' is not encouraged to use in the rendering function, there seems no necessity to remove a capturing listener during virtual DOM diff.

[sqal]

@KingMario yeah sorry, i deleted my answer because i realized that it wasn't proper solution

[KingMario]

@sqal no problem.

[yyx990803]

fixed by merging #4267