allow multi element in children

[cncolder]

If set children type. We need allow element array.

<Flex>
  <Flex.Item />
  <Flex.Item />
</Flex>

  Type '{ children: Element[]; }' is not assignable to type 'Readonly<FlexWebProps>'.
    Types of property 'children' are incompatible.
      Type 'Element[]' is not assignable to type 'Element | undefined'.
        Type 'Element[]' is not assignable to type 'Element'.
          Property 'type' is missing in type 'Element[]'.'
at: '241,13'
source: 'ts'

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Codecov Report

Merging #1442 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master    #1442   +/-   ##
=======================================
  Coverage   63.44%   63.44%           
=======================================
  Files         222      222           
  Lines        4336     4336           
  Branches     1272     1272           
=======================================
  Hits         2751     2751           
  Misses       1584     1584           
  Partials        1        1

Flag	Coverage Δ
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#web	62.62% <ø> (ø)	⬆️

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[paranoidjk]

I am just wonder where is JSX come from ? does it is typescript base type?

[cncolder]

// @types/react/index.d.ts
declare global {
    namespace JSX {
        interface Element extends React.ReactElement<any> { }

[cncolder]

我对 typescript 理解也不深，我认为 JSX.Element 应该能包括所有组件了。但也不能过度使用，例如这里用 React.ReactNode 更合适：

<List>
  <List.Item>abc</List.Item>
</List>

  Type '{ children: string; }' is not assignable to type 'Readonly<ListItemWebProps>'.
    Types of property 'children' are incompatible.
      Type 'string' is not assignable to type 'Element | undefined'.'

[paranoidjk]

    interface ReactElement<P> {
        type: string | ComponentClass<P> | SFC<P>;
        props: P;
        key: Key | null;
    }
    type ReactNode = ReactChild | ReactFragment | boolean | null | undefined;
    type ReactChild = ReactElement<any> | ReactText;
    type ReactFragment = {} | Array<ReactChild | any[] | boolean>;
    type ReactChild = ReactElement<any> | ReactText;

Flex 的 children 应该必须是 Flex.Item 数组吧，还是用 JSX.Element | JSX.Element[] 合理

[cncolder]

其实类型定义这块我有很多想改的地方，但是因为涉及到 rn 源代码，所以不敢做大的改动。

这个项目对类型定义的态度是什么？我看到现在基本上只有 PropsType.tsx 这一个文件里是存放存属性类型，源码里没有逻辑代码以外的东西，PropsType.tsx 这个文件里可不可以写除了 props 之外的代码？

比如 Modal.alert，因为实现上的问题，它不能像 Toast.info 那样导出类型，要想实现这个我能想到的是抽象类。想问下现阶段能接受这样的改动么？

// components/modal/PropsType.tsx
export abstract class ModalComponent<P, S> extends React.Component<P, S> {
  static alert: (
    title: string | JSX.Element,
    message: string | JSX.Element,
    actions?: Action[]
  ) => { close: () => void }
}

// components/modal/Modal.web.tsx
import ModalProps, { ModalComponent } from './PropsType';
export default class Modal extends ModalComponent<ModalProps, any> {
}

[paranoidjk]

@cncolder

我 +1 👍 你的方式更符合我们使用 TypeScript 的意义，单独拆分 PropType 应该是最早低成本的快速从 react propType 迁移到 typescript interface 的方式吧

直接 PR 吧~