【报Bug】TypeError: undefined is not an object (evaluating 't.$scopedSlots')

TypeError: undefined is not an object (evaluating 't.$scopedSlots')
TypeError: undefined is not an object (evaluating 't.$scopedSlots')
TypeError: undefined is not an object (evaluating 't.$scopedSlots')
TypeError: undefined is not an object (evaluating 't.$scopedSlots')

BUG：
nvue uni-app模式

子组件：
使用this.$emit('num',1)

父组件接收：
在methods: {} 获取 $emit 赋值给data 定义的变量就会出现这报错。