diff --git a/src/calendar.vue b/src/calendar.vue
index 0caeff7..2a14620 100644
--- a/src/calendar.vue
+++ b/src/calendar.vue
@@ -258,12 +258,16 @@ export default {
       return date.getTime()
     },
     inBefore (time, startAt) {
-      startAt = startAt || this.startAt
+      if (startAt === undefined) {
+        startAt = this.startAt
+      }
       return (this.notBeforeTime && time < this.notBeforeTime) ||
         (startAt && time < this.getCriticalTime(startAt))
     },
     inAfter (time, endAt) {
-      endAt = endAt || this.endAt
+      if (endAt === undefined) {
+        endAt = this.endAt
+      }
       return (this.notAfterTime && time > this.notAfterTime) ||
         (endAt && time > this.getCriticalTime(endAt))
     },
diff --git a/test/index.spec.js b/test/index.spec.js
index 0b2b7cb..db46fde 100644
--- a/test/index.spec.js
+++ b/test/index.spec.js
@@ -247,24 +247,43 @@ describe('datepicker', () => {
     input.trigger('input')
     input.trigger('change')
     const expectDate = new Date(2018, 8, 10)
-    wrapper.setProps({
-      range: true
-    })
     Vue.nextTick(() => {
-      input.setValue('2018-09-10 ~ 2018-09-11')
-      input.trigger('input')
-      input.trigger('change')
-      const expectRange = [new Date(2018, 8, 10), new Date(2018, 8, 11)]
-      input.setValue('2018-09-10 ~ 2018-08-10')
-      input.trigger('input')
-      input.trigger('change')
       const emitted = wrapper.emitted()
-      expect(emitted.input).toEqual([[expectDate], [expectRange]])
-      expect(emitted['input-error']).toEqual([['2018-09-10 ~ 2018-08-10']])
+      expect(emitted.input).toEqual([[expectDate]])
       done()
     })
   })
 
+  it('type range input should be right', (done) => {
+    wrapper = mount(DatePicker, {
+      propsData: {
+        format: 'YYYY-MM-DD',
+        range: true
+      },
+      sync: false
+    })
+    const input = wrapper.find('input')
+    input.setValue('2018-09-10 ~ 2018-09-11')
+    input.trigger('change')
+    const expectRange = [new Date(2018, 8, 10), new Date(2018, 8, 11)]
+    Vue.nextTick(() => {
+      input.setValue('2018-09-09 ~ 2018-09-12')
+      input.trigger('input')
+      input.trigger('change')
+      const expectRange2 = [new Date(2018, 8, 9), new Date(2018, 8, 12)]
+      Vue.nextTick(() => {
+        input.setValue('2018-09-10 ~ 2018-08-10')
+        input.trigger('input')
+        input.trigger('change')
+        const expectError = '2018-09-10 ~ 2018-08-10'
+        const emitted = wrapper.emitted()
+        expect(emitted.input).toEqual([[expectRange], [expectRange2]])
+        expect(emitted['input-error']).toEqual([[expectError]])
+        done()
+      })
+    })
+  })
+
   it('prop: dateFormat', () => {
     wrapper = mount(DatePicker, {
       propsData: {