support focus and blur event for some form component

test/unit/specs/autocomplete.spec.js

@@ -384,4 +384,60 @@ describe('Autocomplete', () => {
       done();
     }, 500);
   });
+  it('event:focus & blur', done => {
+    vm = createVue({
+      template: `
+        <el-autocomplete
+          ref="input"
+          v-model="state"
+          :fetch-suggestions="querySearch"
+          :trigger-on-focus="false"
+          placeholder="请输入内容autocomplete1"
+        ></el-autocomplete>
+      `,
+      data() {
+        return {
+          restaurants: [],
+          state: ''
+        };
+      },
+      methods: {
+        querySearch(queryString, cb) {
+          var restaurants = this.restaurants;
+          var results = queryString ? restaurants.filter(this.createFilter(queryString)) : restaurants;
+          cb(results);
+        },
+        createFilter(queryString) {
+          return (restaurant) => {
+            return (restaurant.value.indexOf(queryString.toLowerCase()) === 0);
+          };
+        },
+        loadAll() {
+          return [
+            { 'value': '三全鲜食（北新泾店）', 'address': '长宁区新渔路144号' },
+            { 'value': 'Hot honey 首尔炸鸡（仙霞路）', 'address': '上海市长宁区淞虹路661号' },
+            { 'value': '新旺角茶餐厅', 'address': '上海市普陀区真北路988号创邑金沙谷6号楼113' },
+            { 'value': '泷千家(天山西路店)', 'address': '天山西路438号' }
+          ];
+        }
+      },
+      mounted() {
+        this.restaurants = this.loadAll();
+      }
+    }, true);
+
+    const spyFocus = sinon.spy();
+    const spyBlur = sinon.spy();
+
+    vm.$refs.input.$on('focus', spyFocus);
+    vm.$refs.input.$on('blur', spyBlur);
+    vm.$el.querySelector('input').focus();
+    vm.$el.querySelector('input').blur();
+
+    vm.$nextTick(_ => {
+      expect(spyFocus.calledOnce).to.be.true;
+      expect(spyBlur.calledOnce).to.be.true;
+      done();
+    });
+  });
 });