npm

Vue Demi (half in French) is a developing utility
allows you to write Universal Vue Libraries for Vue 2 & 3
See more details in this blog post



## Strategies - `<=2.6`: exports from `vue` + `@vue/composition-api` with plugin auto installing. - `2.7`: exports from `vue` (Composition API is built-in in Vue 2.7). - `>=3.0`: exports from `vue`, with polyfill of Vue 2's `set` and `del` API. ## Usage Install this as your plugin's dependency: ```bash npm i vue-demi # or yarn add vue-demi # or pnpm i vue-demi ``` Add `vue` and `@vue/composition-api` to your plugin's peer dependencies to specify what versions you support. ```jsonc { "dependencies": { "vue-demi": "latest" }, "peerDependencies": { "@vue/composition-api": "^1.0.0-rc.1", "vue": "^2.0.0 || >=3.0.0" }, "peerDependenciesMeta": { "@vue/composition-api": { "optional": true } }, "devDependencies": { "vue": "^3.0.0" // or "^2.6.0" base on your preferred working environment }, } ``` Import everything related to Vue from it, it will redirect to `vue@2` + `@vue/composition-api` or `vue@3` based on users' environments. ```ts import { ref, reactive, defineComponent } from 'vue-demi' ``` Publish your plugin and all is done! > When using with [Vite](https://vitejs.dev), you will need to opt-out the pre-bundling to get `vue-demi` work properly by > ```js > // vite.config.js > export default defineConfig({ > optimizeDeps: { > exclude: ['vue-demi'] > } > }) > ``` ### Extra APIs `Vue Demi` provides extra APIs to help distinguish users' environments and to do some version-specific logic. ### `isVue2` `isVue3` ```ts import { isVue2, isVue3 } from 'vue-demi' if (isVue2) { // Vue 2 only } else { // Vue 3 only } ``` ### `Vue2` To avoid bringing in all the tree-shakable modules, we provide a `Vue2` export to support access to Vue 2's global API. (See [#41](https://github.com/vueuse/vue-demi/issues/41).) ```ts import { Vue2 } from 'vue-demi' if (Vue2) { Vue2.config.ignoredElements.push('x-foo') } ``` ### `install()` Composition API in Vue 2 is provided as a plugin and needs to be installed on the Vue instance before using. Normally, `vue-demi` will try to install it automatically. For some usages where you might need to ensure the plugin gets installed correctly, the `install()` API is exposed to as a safe version of `Vue.use(CompositionAPI)`. `install()` in the Vue 3 environment will be an empty function (no-op). ```ts import { install } from 'vue-demi' install() ``` ## CLI ### Manually Switch Versions To explicitly switch the redirecting version, you can use these commands in your project's root. ```bash npx vue-demi-switch 2 # or npx vue-demi-switch 3 ``` ### Package Aliasing If you would like to import `vue` under an alias, you can use the following command ```bash npx vue-demi-switch 2 vue2 # or npx vue-demi-switch 3 vue3 ``` Then `vue-demi` will redirect APIs from the alias name you specified, for example: ```ts import * as Vue from 'vue3' var isVue2 = false var isVue3 = true var Vue2 = undefined export * from 'vue3' export { Vue, Vue2, isVue2, isVue3, } ``` ### Auto Fix If the `postinstall` hook doesn't get triggered or you have updated the Vue version, try to run the following command to resolve the redirecting. ```bash npx vue-demi-fix ``` ### Isomorphic Testings You can support testing for both versions by adding npm alias in your dev dependencies. For example: ```json { "scripts": { "test:2": "vue-demi-switch 2 vue2 && jest", "test:3": "vue-demi-switch 3 && jest", }, "devDependencies": { "vue": "^3.0.0", "vue2": "npm:vue@2" }, } ``` or ```json { "scripts": { "test:2": "vue-demi-switch 2 && jest", "test:3": "vue-demi-switch 3 vue3 && jest", }, "devDependencies": { "vue": "^2.6.0", "vue3": "npm:vue@3" }, } ``` ## Examples See [examples](./examples). ## Who is using this? - [VueUse](https://github.com/vueuse/vueuse) - Collection of Composition API utils - [@vue/apollo-composable](https://github.com/vuejs/vue-apollo/tree/v4/packages/vue-apollo-composable) - Apollo GraphQL functions for Vue Composition API - [vuelidate](https://github.com/vuelidate/vuelidate) - Simple, lightweight model-based validation - [vue-composition-test-utils](https://github.com/ariesjia/vue-composition-test-utils) - Simple vue composition api unit test utilities - [vue-use-stripe](https://github.com/frandiox/vue-use-stripe) - Stripe Elements wrapper for Vue.js - [@opd/g2plot-vue](https://github.com/open-data-plan/g2plot-vue) - G2plot for vue - [vue-echarts](https://github.com/ecomfe/vue-echarts) - Vue.js component for Apache ECharts. - [fluent-vue](https://github.com/Demivan/fluent-vue) - Vue.js integration for [Fluent.js](https://github.com/projectfluent/fluent.js) - JavaScript implementation of [Project Fluent](https://projectfluent.org) - [vue-datatable-url-sync](https://github.com/socotecio/vue-datatable-url-sync) - Synchronize datatable options and filters with the url to keep user preference even after refresh or navigation - [vue-insta-stories](https://github.com/UnevenSoftware/vue-insta-stories) - Instagram stories in your vue projects. - [vue-tiny-validate](https://github.com/FrontLabsOfficial/vue-tiny-validate) - Tiny Vue Validate Composition - [v-perfect-signature](https://github.com/wobsoriano/v-perfect-signature) - Pressure-sensitive signature drawing for Vue 2 and 3 - [vue-winbox](https://github.com/wobsoriano/vue-winbox) - A wrapper component for WinBox.js that adds the ability to mount Vue components. - [vue-word-highlighter](https://github.com/kawamataryo/vue-word-highlighter) - The word highlighter library for Vue 2 and Vue 3 - [vue-chart-3](https://github.com/victorgarciaesgi/vue-chart-3) - Vue.js component for Chart.js - [json-editor-vue](https://github.com/cloydlau/json-editor-vue) - JSON editor & viewer for Vue 2 and 3. - [kidar-echarts](https://github.com/kidarjs/kidar-echarts) - A simpler echarts component for Vue 2 and 3. - [vue3-sketch-ruler](https://github.com/kakajun/vue3-sketch-ruler) - The zoom operation used for page presentation for Vue 2 and 3( Replace render function with template ) - [vue-rough-notation](https://github.com/Leecason/vue-rough-notation) - RoughNotation wrapper component for Vue 2 and 3. - [vue-request](https://github.com/AttoJS/vue-request) - Vue composition API for data fetching, supports SWR, polling, error retry, cache request, pagination, etc. - [vue3-lazyload](https://github.com/murongg/vue3-lazyload) - A vue3.x image lazyload plugin. - [vue-codemirror6](https://github.com/logue/vue-codemirror6) - CodeMirror6 component for Vue2 and 3. - [@tanstack/vue-query](https://github.com/TanStack/query) - TanStack Query for Vue. > open a PR to add your library ;) ## Underhood See [the blog post](https://antfu.me/posts/make-libraries-working-with-vue-2-and-3/#-introducing-vue-demi). ## License MIT License © 2020 [Anthony Fu](https://github.com/antfu)