feat(List): add error slot

src/list/README.md

@@ -133,3 +133,4 @@ Use [ref](https://vuejs.org/v2/api/#ref) to get List instance and call instance
 | default | List content |
 | loading | Custom loading tips |
 | finished | Custom finished tips |
+| error | Custom error tips |

src/list/README.zh-CN.md

@@ -140,6 +140,7 @@ export default {
 | default | 列表内容 |
 | loading | 自定义底部加载中提示 |
 | finished | 自定义加载完成后的提示文案 |
+| error | 自定义加载失败后的提示文案 |
 
 ## 常见问题
 

src/list/index.js

@@ -136,14 +136,18 @@ export default createComponent({
     },
 
     genErrorText() {
-      if (this.error && this.errorText) {
+      if (this.error) {
+        const text = this.slots('error') || this.errorText;
+
+        if (text) {
           return (
             <div onClick={this.clickErrorText} class={bem('error-text')}>
-            {this.errorText}
+              {text}
             </div>
           );
         }
       }
+    }
   },
 
   render() {

src/list/test/__snapshots__/index.spec.js.snap

@@ -1,5 +1,12 @@
 // Jest Snapshot v1, https://goo.gl/fbAQLP
 
+exports[`error slot 1`] = `
+<div role="feed" class="van-list">
+  <div class="van-list__error-text">Custom Error</div>
+  <div class="van-list__placeholder"></div>
+</div>
+`;
+
 exports[`finished slot 1`] = `
 <div role="feed" class="van-list">
   <div class="van-list__finished-text">Custom Finished</div>

src/list/test/index.spec.js

@@ -83,6 +83,19 @@ test('finished slot', async () => {
   expect(wrapper).toMatchSnapshot();
 });
 
+test('error slot', async () => {
+  const wrapper = mount(List, {
+    propsData: {
+      error: true
+    },
+    scopedSlots: {
+      error: () => 'Custom Error'
+    }
+  });
+
+  expect(wrapper).toMatchSnapshot();
+});
+
 test('immediate check false', async () => {
   const wrapper = mount(List, {
     propsData: {