[improvement] DatetimePicker: add more test cases (#4029)

src/datetime-picker/test/datetime-picker.spec.js

@@ -0,0 +1,32 @@
+import DatetimePicker from '..';
+import { mount } from '../../../test/utils';
+
+test('confirm & cancel event', () => {
+  const onConfirm = jest.fn();
+  const onCancel = jest.fn();
+
+  const wrapper = mount(DatetimePicker, {
+    listeners: {
+      confirm: onConfirm,
+      cancel: onCancel
+    }
+  });
+
+  wrapper.find('.van-picker__confirm').trigger('click');
+  expect(onConfirm).toHaveBeenCalledTimes(1);
+
+  wrapper.find('.van-picker__cancel').trigger('click');
+  expect(onCancel).toHaveBeenCalledTimes(1);
+});
+
+test('time type', () => {
+  const wrapper = mount(DatetimePicker, {
+    propsData: {
+      type: 'time',
+      minHour: 22,
+      minMinute: 58
+    }
+  });
+
+  expect(wrapper).toMatchSnapshot();
+});