Add compatibility with Vue ^2.7.0

[Craig Riley]

So with Vue 2.7.0, Vue now includes the Composition API and <script setup> support.

What it doesn't include, however, is support for reactivityTransform.

At the moment, using 2.7 with this plugin breaks because the plugin is expecting @vue/composition-api as a peer dependency.

Any way to make this work?

[Anthony Fu]

This plugin will not work with 2.7. For built-in reactivityTransform in 2.7, we still wait it to be stable in Vue 3.3 then we can backport it.

[Darren Whitfield]

@antfu A huge selling point for this would be to use the $ref macro as well - as that makes the upgrade from V2.7 (with class component) to V3.0 so so so much easier.

Is there any way to just get $ref to work in 2.7 ?

[ZHAO Jin-Xiang]

Hi, @craigrileyuk @darren-outdev

Due to vuejs/rfcs#369, Reactivity Transform has been dropped. So it seems to we should not use it any more.