fix(jsx): widen jsx and jsxFn children to Child[] (#4947)

Author: ashunar0

src/jsx/base.test.tsx

@@ -1,6 +1,6 @@
 /** @jsxImportSource ./ */
 
-import type { JSXNode } from './base'
+import type { Child, JSXNode } from './base'
 // eslint-disable-next-line @typescript-eslint/no-unused-vars
 import { cloneElement, jsx, Fragment } from './base'
 
@@ -43,4 +43,10 @@ describe('createElement', () => {
     expect(element.type).toBe('svg')
     expect(element.ref).toBe(ref)
   })
+
+  it('should accept a Child-typed value as a child', () => {
+    const child: Child = <span>inner</span>
+    const element = jsx('div', null, child) as unknown as JSXNode
+    expect(element.toString()).toBe('<div><span>inner</span></div>')
+  })
 })

src/jsx/base.ts

@@ -302,11 +302,7 @@ export class JSXFragmentNode extends JSXNode {
   }
 }
 
-export const jsx = (
-  tag: string | Function,
-  props: Props | null,
-  ...children: (string | number | HtmlEscapedString)[]
-): JSXNode => {
+export const jsx = (tag: string | Function, props: Props | null, ...children: Child[]): JSXNode => {
   props ??= {}
   if (children.length) {
     props.children = children.length === 1 ? children[0] : children
@@ -321,11 +317,7 @@ export const jsx = (
 }
 
 let initDomRenderer = false
-export const jsxFn = (
-  tag: string | Function,
-  props: Props,
-  children: (string | number | HtmlEscapedString)[]
-): JSXNode => {
+export const jsxFn = (tag: string | Function, props: Props, children: Child[]): JSXNode => {
   if (!initDomRenderer) {
     for (const k in domRenderers) {
       // eslint-disable-next-line @typescript-eslint/no-explicit-any