LabelsSelect DropdownHiddenInput Component

app/assets/javascripts/vue_shared/components/sidebar/labels_select/dropdown_hidden_input.vue

+<script>
+export default {
+  props: {
+    name: {
+      type: String,
+      required: true,
+    },
+    label: {
+      type: Object,
+      required: true,
+    },
+  },
+};
+</script>
+
+<template>
+  <input
+    type="hidden"
+    :name="name"
+    :value="label.id"
+  />
+</template>

spec/javascripts/vue_shared/components/sidebar/labels_select/dropdown_hidden_input_spec.js

+import Vue from 'vue';
+
+import dropdownHiddenInputComponent from '~/vue_shared/components/sidebar/labels_select/dropdown_hidden_input.vue';
+
+import { mockLabels } from './mock_data';
+
+import mountComponent from '../../../../helpers/vue_mount_component_helper';
+
+const createComponent = (name = 'label_id[]', label = mockLabels[0]) => {
+  const Component = Vue.extend(dropdownHiddenInputComponent);
+
+  return mountComponent(Component, {
+    name,
+    label,
+  });
+};
+
+describe('DropdownHiddenInputComponent', () => {
+  let vm;
+
+  beforeEach(() => {
+    vm = createComponent();
+  });
+
+  afterEach(() => {
+    vm.$destroy();
+  });
+
+  describe('template', () => {
+    it('renders input element of type `hidden`', () => {
+      expect(vm.$el.nodeName).toBe('INPUT');
+      expect(vm.$el.getAttribute('type')).toBe('hidden');
+      expect(vm.$el.getAttribute('name')).toBe(vm.name);
+      expect(vm.$el.getAttribute('value')).toBe(`${vm.label.id}`);
+    });
+  });
+});