Datasets:
| myChart.setOption({}) 时 lines.data 丢失 | |
| ### Version | |
| 4.8.0 | |
| ### Steps to reproduce | |
| myChart.setOption({}) 时, lines类型的线数据会丢失, 其他类型的数据(如line)依然存在. | |
| 这个方法的行为是不是应该统一? | |
| https://gallery.echartsjs.com/editor.html?c=xeqTwJtMgx&v=1 | |
| - before: | |
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| - after: | |
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| ### What is expected? | |
| myChart.setOption({}) 要么数据全丢, 要么全保留 | |
| ### What is actually happening? | |
| lines类型的线数据丢失 | |
| <!-- This issue is generated by echarts-issue-helper. DO NOT REMOVE --> | |
| ## Relevant pre-fix discussion | |
| ### Issue #12836 | |
| #### Comment at 2020-06-22T14:58:12Z | |
| @myshzzx | |
| 代码，在本地运行，如图所示，可以显示lines类型的线数据 | |
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