Extending SFC components does not work.

[Morgul]

Attempting to follow the Vue Typescript Guide leads to declaring a sample component like this:

<template>
    <div id="main-app">
      Message: {{ msg }}
    </div>
</template>

<style lang="scss">
    #main-app {
        height: calc(100% - 64px);
    }
</style>

<script lang="ts">
    import Vue from 'vue';
    export default Vue.extend({
        data()
        {
            return {
                msg: 'Hello, Vue!'
            }
        }
    });
</script>

However, compiling this with snowpack-plugin-vue2 yields the following error message:

[mszekiel]

I have this error and it would be really helpful to be working :(

[Morgul]

I haven't had a chance to start digging into the output to understand why one works, and the other doesn't. My plan is to keep working on in it in the upcoming week.

[Morgul]

Just an update (more for myself as a reminder when I get back to this). I've spent some time this afternoon digging into this, and comparing the Vue3 compiler output to the Vue2 one, they both output the script section identically:

import Vue from "vue";
const defaultExport = Vue.extend({
  name: "SimpleVue",
  data() {
    return {
      msg: "Hello!"
    };
  }
});

Whatever the bug is, it's actually at the Vue level; something about how Vue.extends works in Vue2 vs Vue3. As a side note, I have not confirmed this works in Vue 3; that would be something to try as well; maybe this is just broken with how Snowpack's building the module to wrap an SFC?

[Morgul]

Good news! looks like vue-loader has the solution, I think:

https://github.com/vuejs/vue-loader/blob/master/lib/runtime/componentNormalizer.js#L17-L20

I've gotta figure out the most minimal way to shove this into the plugin, but I think it should fix this issue.

As a workaround, @mszekiel, you should be able to just stick .options on the end, i.e.:

export default Vue.extend({
  name: "SimpleVue",
  data() {
    return {
      msg: "Hello!"
    };
  }
}).options;

That seemed to work in the brief test I just did. I'll work on a new version of the plugin with a proper fix shortly.

[Morgul]

This is fixed in v0.2.0, which was just published.