Pinia Error in Vue 2

[tiojevero]

Reproduction

I got error Can't import the named export from non EcmaScript module (only default export is available) while using Pinia in Vue 2.

Steps to reproduce the behavior

1. Use vue-cli to create a vue 2 app.
2. Run yarn add pinia @vue/composition-api
3. Edit the main.js

import Vue from "vue";
import { createPinia, PiniaVuePlugin } from "pinia";

Vue.use(PiniaVuePlugin);
const pinia = createPinia();


new Vue({
    render: (h) => h(App),
    el: "#app",
    pinia,
});

4. Run yarn serve

Expected behavior

The vue 2 app run without Can't import the named export from non EcmaScript module (only default export is available) error.

Actual behavior

 ERROR  Failed to compile with 19 errors                                            22:11:24
 error  in ./node_modules/pinia/dist/pinia.mjs

Can't import the named export 'computed' from non EcmaScript module (only default export is 
available)

 error  in ./node_modules/pinia/dist/pinia.mjs

Can't import the named export 'del' from non EcmaScript module (only default export is available)

 error  in ./node_modules/pinia/dist/pinia.mjs

Can't import the named export 'effectScope' from non EcmaScript module (only default export 
is available)

 error  in ./node_modules/pinia/dist/pinia.mjs

Can't import the named export 'getCurrentInstance' from non EcmaScript module (only default 
export is available)

 error  in ./node_modules/pinia/dist/pinia.mjs

Can't import the named export 'inject' from non EcmaScript module (only default export is available)

 error  in ./node_modules/pinia/dist/pinia.mjs

Can't import the named export 'isReactive' from non EcmaScript module (only default export is available)

 error  in ./node_modules/pinia/dist/pinia.mjs

Can't import the named export 'isRef' from non EcmaScript module (only default export is available)

 error  in ./node_modules/pinia/dist/pinia.mjs

Can't import the named export 'isVue2' from non EcmaScript module (only default export is available)

 error  in ./node_modules/pinia/dist/pinia.mjs

Can't import the named export 'markRaw' from non EcmaScript module (only default export is available)

 error  in ./node_modules/pinia/dist/pinia.mjs

Can't import the named export 'nextTick' from non EcmaScript module (only default export is 
available)

 error  in ./node_modules/pinia/dist/pinia.mjs

Can't import the named export 'onUnmounted' from non EcmaScript module (only default export 
is available)

 error  in ./node_modules/pinia/dist/pinia.mjs

Can't import the named export 'reactive' from non EcmaScript module (only default export is 
available)

 error  in ./node_modules/pinia/dist/pinia.mjs

Can't import the named export 'ref' from non EcmaScript module (only default export is available)

 error  in ./node_modules/pinia/dist/pinia.mjs

Can't import the named export 'set' from non EcmaScript module (only default export is available)

 error  in ./node_modules/pinia/dist/pinia.mjs

Can't import the named export 'toRaw' from non EcmaScript module (only default export is available)

 error  in ./node_modules/pinia/dist/pinia.mjs

Can't import the named export 'toRef' from non EcmaScript module (only default export is available)

 error  in ./node_modules/pinia/dist/pinia.mjs

Can't import the named export 'toRefs' from non EcmaScript module (only default export is available)

 error  in ./node_modules/pinia/dist/pinia.mjs

Can't import the named export 'unref' from non EcmaScript module (only default export is available)

 error  in ./node_modules/pinia/dist/pinia.mjs

Can't import the named export 'watch' from non EcmaScript module (only default export is available)

Additional information

  "dependencies": {
    "@vue/composition-api": "^1.4.6",
    "pinia": "^2.0.11",
    "vue": "^2.6.11",
  }

[philibe]

Same than #675 ? (except the vue version).

https://github.com/vuejs/pinia/blob/v2/packages/docs/cookbook/migration-v1-v2.md#webpack-4-support