How to use JSDoc to document a Vue component with script setup?

Question

I'm building a Vue library with TypeScript. I'd like to export the documentation of the components, like I do with ordinary functions.

Previously we would do this:

<script>
/**
 * This is the documentation of my component.
 */
export default {
}
</script>

<template></template>

But now with script setup:

<script setup lang="ts">
</script>

<template></template>

How do we document the component?

Answer 1

With <script setup> you can't use JSDoc on the component export.

It's a compiler syntaxic sugar that gets out the export of the setup function, so you obviously can't comment a function that is "generated" by the compiler.

If you really needs JSDoc, you should use a regular <script> with a default export :)

<script>
/** This is my nice component documentation */
export default {
  name: 'MyComponent',
  setup() {
    // your code
  }, 
}
</script>

Also works with the typescript defineComponent wrapper:

<script>
import { defineComponent } from 'vue'

/** This is my nice component documentation */
export default defineComponent({
  name: 'MyComponent',
  setup() {
    // your code
  }
})
</script>

EDIT: as mentionned by @EstusFlask in the comments, you can mix both <script setup> and <script> on a SFC component (see docs) So you can use the regular script to expose your JSDoc.

<script setup>
// component setup. Takes priority over the eventual `setup()` function of the export object in <script>.
</script>

<script>
/** This is my nice component documentation */
export default {
  name: 'MyComponent',
}
</script>