Set labelInvalue in select component, placeholder dispaly incorrect！

• I have searched the issues of this repository and believe that this is not a duplicate.

Version

3.1.4

Environment

mac 10.13.5 , chrome 67.0.3396.87 , react 16.2.0

Reproduction link

https://codepen.io/littlelane/pen/eKVyRM?editors=0010

Steps to reproduce

		const mipayFormOptios = [
			{
				label: '医保中心',
				type: 'select',
				placeholder: '请选择医保中心',
				field: 'accountNo',
				initialValue: handleType === 'update' ? {key: thisRecord.accountNo, label: thisRecord.medicalCenterName } : {key: ''},
				options: { options: medicalList, label: 'medicalCenterName', value: 'medicalCenterNo' },
				labelInValue: true,
				rules: [{
					required: true, message: '请选择医保中心',
				}]
			}, {
				label: '医疗机构编号',
				type: 'input',
				placeholder: '请输入医疗机构编号',
				field: 'medicalJournalNo',
				initialValue: thisRecord.medicalJournalNo,
				maxLength: 40,
				rules: [{
					required: true, message: '请输入医疗机构编号',
				}, {
					pattern: CODE_REG, message: '请输入长度最大为40位的包含数字、字母和下划线的编码'
				}]
			}
		]

What is expected?

expect when set labelInvalue in select component，the select accept type of value not only {key: string | number, label: ReactNode}，but also {key: string | number | undefined, label: ReactNode} ! Because the select component only set undefined, the placeholder can display correct！

What is actually happening?

the select accept value type only {key: string | number, label: ReactNode}, when select component init the placeholder can’t display correct！

[lovemegowin]

这个bug没修复就这么关了。。。。

[ryanjwessel]

Actually, I did get it to display the placeholder. Basically, my value prop went from this:

value={{key: filter.keyName, label: filter.labelName}}

to this:

value={filter ? { key: filter.keyName, label: filter.labelName } : undefined }

That will display the placeholder correctly, but this will definitely be confusing for other developers that look at this code in the future.