fix: handle additional args in components' with event modifiers

[mshahbazi]

Additional args are not passed to components events with modifiers.

with a component template like this
<input @keyup="$emit('my-keyup', $event, var1, var2)"/>
triggering the event, e.g.
<my-component @my-keyup.enter="onMyKeyup"/>
the onMyKeyup receives the $event, but not var1 and var2

hope this PR resolves the issue.

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• Bugfix
• Feature
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• Yes
• No

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[xunita]

No need of additional args, you can achieve it using an object instead.
<input @keyup="$emit('my-keyup', object)"/>
Where your object looks like :
{ event: $event, var1: var1, var2: var2, }

[mshahbazi]

@sopegue,
Thank you for your comment,
Digging into the code revealed that .enter modifier is checked by something like if (aruments[0].keyCode == 13) so { event: $event, var1: var1, var2: var2, } will not work.
Simply put, to use event modifier in a component, e.g., @my-keyup.enter, $event need to be passed as the first argument, and surprisingly, the rest is ignored.

[xunita]

I tried your previous attempt and my solution, both work properly locally and in production.
The event sill fire even if not enter key pressed.
However, tried it on codesandbox but did not work, wondering why...

[mshahbazi]

The codesandbox with your solution raises Cannot read property 'indexOf' of undefined" which is probably rooted in getKeyFilter where checks the existence of key in $event, i.e., if(!$event.type.indexOf('key') ... return null. In your code, $event is set as { event: $event, var1, var2 } that does not include the key.
Although it does not resolve the issue, to get rid of the error, you may add key, keyCode, target to the object. Please see codesandbox

[posva]

Duplicate of #10958