Nuxt/test/fixtures/basic/plugins/vuex-module.js

export default function ({ store }) {
  store.registerModule('simpleModule', {
    namespaced: true,
    state: () => ({
      mutateMe: 'not mutated'
    }),
    actions: {
      mutate ({ commit }) {
        commit('mutate')
      }
    },
    mutations: {
      mutate (state) {
        state.mutateMe = 'mutated'
      }
    }
  })

  if (process.server) { return }

  store.registerModule('clientsideModule', {
    namespaced: true,
    state: () => ({
      initialised: true
    })
  })
}