fix: add ref only when support

[zombieJ]

fix ant-design/ant-design#21921

[vercel]

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[codecov]

Codecov Report

Merging #174 into master will increase coverage by 0.08%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master     #174      +/-   ##
==========================================
+ Coverage    85.6%   85.68%   +0.08%     
==========================================
  Files           7        7              
  Lines         500      503       +3     
  Branches      144      145       +1     
==========================================
+ Hits          428      431       +3     
  Misses         72       72

Impacted Files	Coverage Δ
src/index.tsx	82.12% <100%> (+0.16%)	⬆️

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[AshoneA]

原来获取 child 的 ref 只是为了保持外界 ref 调用一致吗？我还以为跟 pop 的位置有关系。👍

[zombieJ]

原本实现是 findDOMNode 严格模式会报错，所以改成了 ref。但是实际上很多场景都不适用，希望 React 快点出替代方案。

[AshoneA]

那个 Fragment 的提案被关闭了... 感觉还得再等好一会儿才能有替代方案。

[zombieJ]

嗯，既不推荐又不给替代方案比较蛋疼。