feat: allow passing instantiated Vuex store (#232)

* feat: allow passing instantiated Vuex store

* Update types/index.d.ts

Co-authored-by: Adrià Fontcuberta <afontcu@gmail.com>

Author: blimmer

src/__tests__/vuex.js

@@ -1,5 +1,6 @@
 import '@testing-library/jest-dom'
 import {render, fireEvent} from '@testing-library/vue'
+import Vuex from 'vuex'
 
 import VuexTest from './components/Store/VuexTest'
 import {store} from './components/Store/store'
@@ -54,3 +55,33 @@ test('can render with vuex with custom store', async () => {
   await fireEvent.click(getByText('-'))
   expect(getByTestId('count-value')).toHaveTextContent('1000')
 })
+
+test('can render with an instantiated Vuex store', async () => {
+  const {getByTestId, getByText} = render(VuexTest, {
+    store: new Vuex.Store({
+      state: {count: 3},
+      mutations: {
+        increment(state) {
+          state.count++
+        },
+        decrement(state) {
+          state.count--
+        },
+      },
+      actions: {
+        increment(context) {
+          context.commit('increment')
+        },
+        decrement(context) {
+          context.commit('decrement')
+        },
+      },
+    }),
+  })
+
+  await fireEvent.click(getByText('+'))
+  expect(getByTestId('count-value')).toHaveTextContent('4')
+
+  await fireEvent.click(getByText('-'))
+  expect(getByTestId('count-value')).toHaveTextContent('3')
+})

src/render.js

@@ -31,7 +31,7 @@ function render(
     const Vuex = require('vuex')
     localVue.use(Vuex)
 
-    vuexStore = new Vuex.Store(store)
+    vuexStore = store instanceof Vuex.Store ? store : new Vuex.Store(store)
   }
 
   if (routes) {

types/test.ts

@@ -1,4 +1,5 @@
 import Vue from 'vue'
+import Vuex from 'vuex'
 import {render, fireEvent, screen, waitFor} from '@testing-library/vue'
 
 declare const elem: Element
@@ -127,6 +128,30 @@ export function testConfigCallback() {
   })
 }
 
+export function testInstantiatedStore() {
+  render(SomeComponent, {
+    store: new Vuex.Store({
+      state: {count: 3},
+      mutations: {
+        increment(state) {
+          state.count++
+        },
+        decrement(state) {
+          state.count--
+        },
+      },
+      actions: {
+        increment(context) {
+          context.commit('increment')
+        },
+        decrement(context) {
+          context.commit('decrement')
+        },
+      },
+    }),
+  })
+}
+
 /*
 eslint
   testing-library/prefer-explicit-assert: "off",