Form: label-width supports width auto

[ziyoung]

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[de1ck]

@ziyoung
When I use label-width: auto
[Vue warn]: Error in beforeDestroy hook: "Error: [ElementForm]unpected width "
found in

---> at packages/form/src/label-wrap.vue

[Shu-Ji]

@ziyoung When I use label-width="auto" on el-form which is located in an el-tab, will also get the error

[ElementForm]unpected width 

There is a demo:

https://codepen.io/bh20077/pen/NVObdd

Main code from the demo:

#app
  p
    el-button(type="primary" @click="toggleCard") 隐藏
    
  p 请打开控制台，然后点击上面的按钮，将会隐藏下面的 card，此时在控制台会报错。经过排查是 el-form 上面的 label-width = "auto" 属性导致的，如果不设置或者设置居 label-width="100px" 就不会报错
  
  el-card(v-if="show_card")
    //- 直接写在这里面也不会报错的，但是将 form 写到下面的 el-tabs 里面就会报错
    //- el-form(label-width="auto")
    //-       el-form-item
    //-         el-form-item(label="任务名称")
    //-             el-input(v-model="task_name" type="text" placeholder="请填写任务名称")
    
    el-tabs(stretch)
      el-tab-pane(label="基本信息")
        //- 这里的 label-width = "auto" 在点击按钮后的时候会报错
        el-form(label-width="auto")
          el-form-item
            el-form-item(label="任务名称")
                el-input
      el-tab-pane(label="运行参数") 运行参数

[kooriookami]

Use label-width="auto" get error.
I got this error when I close el-form, ' [ElementForm]unpected width '.

[VanLiuZhi]

I also encountered this problem, although it did not affect, but there was an error.Hope to fix this problem

[ziyoung]

I also encountered this problem, although it did not affect, but there was an error.Hope to fix this problem

@VanLiuZhi Please create a new issue.