As stated in the docs, this handle only catches errors during render:

If a runtime error occurs during a component’s render, it will be passed to the global Vue.config.errorHandler config function if it has been set.

Demo:

https://jsfiddle.net/Linusborg/o2azdhbx/1/

But it might be a good enhancement to make this possible for lifecycle hooks as well.

Optinions @vuejs/vue ?

Why is this not considered an error during render? Did it not happen while rendering the parent component?

It's quite annoying, because a non-cought error can stop a SPA working.

For example using a small catch around watcher.run() in flushSchedulerQueue makes live easier if an error happens while evaluating a watcher:

function flushSchedulerQueue () {
    ...
    try {
		watcher.run();
    }
    catch(e) {
		config.errorHandler.call(null, e, watcher.vm);
    }
    ...
}

Implemented in dev, will land in 2.2.

still exist in the newest Vue 2.2.4
hope this will land soon~~~

This did land in 2.2.

If you still experience problems, please open a new issue, with a live reproduction on jsfiddle.

move to #5198