require online location for online only events

components/WhereInput.vue

@@ -45,6 +45,7 @@ v-row.mb-4
         :prepend-icon='mdiLink'
         :hint="$t('event.online_locations_help')"
         :label="$t('event.online_locations')"
+        :rules="[$validators.required('event.online_locations')]"
         clearable chips small-chips multiple deletable-chips hide-no-data hide-selected persistent-hint
         :delimiters="[',', ';', '; ']"
         :items="onlineLocations"

plugins/validators.js

@@ -4,7 +4,7 @@ export default ({ app }, inject) => {
   const $t = app.i18n.t.bind(app.i18n)
   const validators = {
     required (fieldName) {
-      return value => !!value || $t('validators.required', { fieldName: $t(fieldName) })
+      return v => !(v===undefined || v===null || v.length <= 0) || $t('validators.required', { fieldName: $t(fieldName) })
     },
     email: [
       v => !!v || $t('validators.required', { fieldName: $t('common.email') }),