LabelsSelect DropdownButton Component

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

+<script>
+import { __, s__, sprintf } from '~/locale';
+
+export default {
+  props: {
+    abilityName: {
+      type: String,
+      required: true,
+    },
+    fieldName: {
+      type: String,
+      required: true,
+    },
+    updatePath: {
+      type: String,
+      required: true,
+    },
+    labelsPath: {
+      type: String,
+      required: true,
+    },
+    namespace: {
+      type: String,
+      required: true,
+    },
+    labels: {
+      type: Array,
+      required: true,
+    },
+    showExtraOptions: {
+      type: Boolean,
+      required: true,
+    },
+  },
+  computed: {
+    dropdownToggleText() {
+      if (this.labels.length === 0) {
+        return __('Label');
+      }
+
+      if (this.labels.length > 1) {
+        return sprintf(s__('LabelSelect|%{firstLabelName} +%{remainingLabelCount} more'), {
+          firstLabelName: this.labels[0].title,
+          remainingLabelCount: this.labels.length - 1,
+        });
+      }
+
+      return this.labels[0].title;
+    },
+  },
+};
+</script>
+
+<template>
+  <button
+    type="button"
+    ref="dropdownButton"
+    class="dropdown-menu-toggle wide js-label-select js-multiselect js-context-config-modal"
+    data-toggle="dropdown"
+    :class="{ 'js-extra-options': showExtraOptions }"
+    :data-ability-name="abilityName"
+    :data-field-name="fieldName"
+    :data-issue-update="updatePath"
+    :data-labels="labelsPath"
+    :data-namespace-path="namespace"
+    :data-show-any="showExtraOptions"
+  >
+    <span class="dropdown-toggle-text">
+      {{ dropdownToggleText }}
+    </span>
+    <i
+      aria-hidden="true"
+      class="fa fa-chevron-down"
+      data-hidden="true"
+    >
+    </i>
+  </button>
+</template>

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

+import Vue from 'vue';
+
+import dropdownButtonComponent from '~/vue_shared/components/sidebar/labels_select/dropdown_button.vue';
+
+import { mockConfig, mockLabels } from './mock_data';
+
+import mountComponent from '../../../../helpers/vue_mount_component_helper';
+
+const componentConfig = Object.assign({}, mockConfig, {
+  fieldName: 'label_id[]',
+  labels: mockLabels,
+  showExtraOptions: false,
+});
+
+const createComponent = (config = componentConfig) => {
+  const Component = Vue.extend(dropdownButtonComponent);
+
+  return mountComponent(Component, config);
+};
+
+describe('DropdownButtonComponent', () => {
+  let vm;
+
+  beforeEach(() => {
+    vm = createComponent();
+  });
+
+  afterEach(() => {
+    vm.$destroy();
+  });
+
+  describe('computed', () => {
+    describe('dropdownToggleText', () => {
+      it('returns text as `Label` when `labels` prop is empty array', () => {
+        const mockEmptyLabels = Object.assign({}, componentConfig, { labels: [] });
+        const vmEmptyLabels = createComponent(mockEmptyLabels);
+        expect(vmEmptyLabels.dropdownToggleText).toBe('Label');
+        vmEmptyLabels.$destroy();
+      });
+
+      it('returns first label name with remaining label count when `labels` prop has more than one item', () => {
+        const mockMoreLabels = Object.assign({}, componentConfig, {
+          labels: mockLabels.concat(mockLabels),
+        });
+        const vmMoreLabels = createComponent(mockMoreLabels);
+        expect(vmMoreLabels.dropdownToggleText).toBe('Foo Label +1 more');
+        vmMoreLabels.$destroy();
+      });
+
+      it('returns first label name when `labels` prop has only one item present', () => {
+        expect(vm.dropdownToggleText).toBe('Foo Label');
+      });
+    });
+  });
+
+  describe('template', () => {
+    it('renders component container element of type `button`', () => {
+      expect(vm.$el.nodeName).toBe('BUTTON');
+    });
+
+    it('renders component container element with required data attributes', () => {
+      expect(vm.$el.dataset.abilityName).toBe(vm.abilityName);
+      expect(vm.$el.dataset.fieldName).toBe(vm.fieldName);
+      expect(vm.$el.dataset.issueUpdate).toBe(vm.updatePath);
+      expect(vm.$el.dataset.labels).toBe(vm.labelsPath);
+      expect(vm.$el.dataset.namespacePath).toBe(vm.namespace);
+      expect(vm.$el.dataset.showAny).not.toBeDefined();
+    });
+
+    it('renders dropdown toggle text element', () => {
+      const dropdownToggleTextEl = vm.$el.querySelector('.dropdown-toggle-text');
+      expect(dropdownToggleTextEl).not.toBeNull();
+      expect(dropdownToggleTextEl.innerText.trim()).toBe('Foo Label');
+    });
+
+    it('renders dropdown button icon', () => {
+      const dropdownIconEl = vm.$el.querySelector('i.fa');
+      expect(dropdownIconEl).not.toBeNull();
+      expect(dropdownIconEl.classList.contains('fa-chevron-down')).toBe(true);
+    });
+  });
+});