bugfix: ignore Enter key triggered by IME

[yaquawa]

Languages like Japanese or Chinese input characters by something called IME. You may not familiar to this if you only input English characters, but people using IME will have trouble to "Add a new tag" by entering the "Enter" key, because the IME also use Enter key to confirm the user's current input which is different from regular Enter key.

You can use event.keyCode === 229 to detect if the event is triggered by IME or a regular Enter key.
This PR fix the bug by add the above logic to the Enter key handler.
(I have tested the code in my environment, which works great)

[hiromi2424]

Why this PR has been ignored about a half-year?
This is so great support to all languages IME needed.

In particular there is a workaround:

<script setup>
import { ref, onMounted } from 'vue';
import Multiselect from '@vueform/multiselect';

const multiselect = ref(null);
onMounted(() => {
  const defaultHandleKeydown = multiselect.value.handleKeydown;
  multiselect.value.handleKeydown = (e) => {
    if (e.key === 'Enter' && e.keyCode === 229) {
      e.preventDefault();
      return;
    }
    defaultHandleKeydown(e);
  };
});
</script>

<template>
  <Multiselect
    ref="multiselect"
    ...
  / >
</template>

But this is a very 'hucky' way that is not documented, not expected in usage and hard to read/understand.

Vue was developed under nations/cultures that uses IME, therefore libraries around Vue should respect such expectations.
I appreciate any actions from maintainers. thank you.

[ScopeyNZ]

FYI I think the approriate way to do this with the KeyboardEvent API is to use the isComposing instance property: https://developer.mozilla.org/en-US/docs/Web/API/KeyboardEvent/isComposing

[adamberecz]

Thanks for reporting and for the effort! As you PR doesn't contain tests I close it without merging, but the issue got fixed with your solution in 2.5.7.

[hiromi2424]

@adamberecz Thank you so much!!!