[new feature] Field: add arrow-direction prop (#3679)

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

@@ -1,5 +1,14 @@
 // Jest Snapshot v1, https://goo.gl/fbAQLP
 
+exports[`arrow-direction prop 1`] = `
+<div class="van-cell van-cell--clickable van-field">
+  <div class="van-cell__value van-cell__value--alone">
+    <div class="van-field__body"><input type="text" class="van-field__control"></div>
+  </div><i class="van-icon van-icon-arrow-up van-cell__right-icon">
+    <!----></i>
+</div>
+`;
+
 exports[`clearable 1`] = `
 <div class="van-cell van-field">
   <div class="van-cell__value van-cell__value--alone">

src/field/test/index.spec.js

@@ -235,3 +235,13 @@ test('label-class prop', () => {
   });
   expect(wrapper).toMatchSnapshot();
 });
+
+test('arrow-direction prop', () => {
+  const wrapper = mount(Field, {
+    propsData: {
+      isLink: true,
+      arrowDirection: 'up'
+    }
+  });
+  expect(wrapper).toMatchSnapshot();
+});