通用高阶 React 组件给出类型错误

Question

IFoo我正在尝试编写一个通用的 React 组件，它需要两种类型（或）之一的 propsIBar以及接受所选类型的 props 的组件。

为什么下面的不起作用？

操场

import React from 'react';

interface IFoo {
  x: string;
}

interface IBar {
  x: number;
}

const foo: React.FunctionComponent<IFoo> = (props: IFoo) => {
  console.log("hello from foo!");
  return <div>foo</div>
};

const bar: React.FunctionComponent<IBar> = (props: IBar) => {
  console.log("hello from bar!");
  return <div>bar</div>
};

interface IProps<T> { 
    props: T[];
    Component: React.FunctionComponent<T>;
}


class HigherOrderComponent<T extends IBar | IFoo> extends React.Component<IProps<T>> { 
    render() {
        const { props, Component } = this.props;
        return (<div>
            {props.map(prop => <Component {...prop}/>)};
        </div>)
     }
}

这将返回以下错误：

Type 'T' is not assignable to type 'IntrinsicAttributes & T & { children?: ReactNode; }'.
  Type 'IFoo | IBar' is not assignable to type 'IntrinsicAttributes & T & { children?: ReactNode; }'.
    Type 'IFoo' is not assignable to type 'IntrinsicAttributes & T & { children?: ReactNode; }'.
      Type 'IFoo' is not assignable to type 'T'.
        'IFoo' is assignable to the constraint of type 'T', but 'T' could be instantiated with a different subtype of constraint 'IFoo | IBar'.
          Type 'T' is not assignable to type 'IntrinsicAttributes'.
            Type 'IFoo | IBar' is not assignable to type 'IntrinsicAttributes'.
              Type 'IFoo' has no properties in common with type 'IntrinsicAttributes'.(2322)

Answer 1

快速修复是添加：

{props.map((prop: T & {}) => <Component {...prop}/>)};

我认为问题在于扩展运算符和联合类型（如果只有一种类型，则可以正常工作）。我知道 TS 以前也遇到过这样的问题:(

希望这可以帮助 ：）