Prop validation treats optional props as required

• I have searched through existing issues
• I have read through docs
• I have read FAQ
• I have tried restarting VS Code or running Vetur: Restart VLS

Info

• Platform: Linux
• Vetur version: Latest
• VS Code version: N/A (i’m using neovim, coc and coc-vetur)

Problem

When using following prop definition propName: String, vetur considers it required. But for vue it’s optional.

https://github.com/vuejs/vetur/blob/master/server/src/modes/script/componentInfo.ts#L371 I think problem is here. And i can try to fix it myself and make PR, if this is really a bug and not desired behaviour. For me it looks like a bug.

Reproducible Case

https://github.com/last-partizan/vetur-props-validation-bug

This is Test.vue

<template>
  <div>
    {{ foo }}
  </div>
</template>

<script>
export default {
  props: {
    foo: String,
    bar: {type: String, required: false},
  }
}
</script>

This is App.vue

<template>
  <Test />
</template>

<script>
import Test from './Test.vue'

export default {
  components: { Test },
}
</script>

This is vetur warning: <Test> misses props: foo

[yoyo930021]

Please set "vetur.validation.templateProps": false when you don’t need it.

Another information: https://github.com/vuejs/vetur/issues/2235#issuecomment-688013007

[yoyo930021]

https://vuejs.github.io/vetur/guide/interpolation.html#prop-validation

https://github.com/vuejs/vetur/issues/2141#issuecomment-674117099

It is by design.