add getInput method to el-input

Author: Zhi

packages/autocomplete/src/autocomplete.vue

@@ -255,7 +255,7 @@
         $input.setAttribute('aria-activedescendant', `${this.id}-item-${this.highlightedIndex}`);
       },
       getInput() {
-        return this.$refs.input.$refs.input || this.$refs.input.$refs.textarea;
+        return this.$refs.input.getInput();
       }
     },
     mounted() {

packages/input/src/input.vue

@@ -221,10 +221,10 @@
 
     methods: {
       focus() {
-        (this.$refs.input || this.$refs.textarea).focus();
+        this.getInput().focus();
       },
       blur() {
-        (this.$refs.input || this.$refs.textarea).blur();
+        this.getInput().blur();
       },
       getMigratingConfig() {
         return {
@@ -245,7 +245,7 @@
         }
       },
       select() {
-        (this.$refs.input || this.$refs.textarea).select();
+        this.getInput().select();
       },
       resizeTextarea() {
         if (this.$isServer) return;
@@ -287,7 +287,7 @@
         // set input's value, in case parent refuses the change
         // see: https://github.com/ElemeFE/element/issues/12850
         this.$nextTick(() => {
-          let input = this.$refs.input || this.$refs.textarea;
+          let input = this.getInput();
           input.value = this.value;
         });
       },
@@ -325,6 +325,9 @@
         this.$emit('input', '');
         this.$emit('change', '');
         this.$emit('clear');
+      },
+      getInput() {
+        return this.$refs.input || this.$refs.textarea;
       }
     },