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Module

x/htm/jsx.ts

Create `text/html` response with JSX.
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/**MIT License
Copyright (c) 2021 - present, Yusuke Wada and Hono contributors
Permission is hereby granted, free of charge, to any person obtaining a copyof this software and associated documentation files (the "Software"), to dealin the Software without restriction, including without limitation the rightsto use, copy, modify, merge, publish, distribute, sublicense, and/or sellcopies of the Software, and to permit persons to whom the Software isfurnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in allcopies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS ORIMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THEAUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHERLIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THESOFTWARE.*/
type Child = string | number | JSXNode | Child[];
type Props = { // deno-lint-ignore no-explicit-any [key: string]: any; class?: string; style?: string; dangerouslySetInnerHTML?: { __html: string }; onclick?: string;};
declare global { namespace JSX { type Element = | JSXFunctionNode | JSXNode | JSXFragmentNode; interface IntrinsicElements { [tagName: string]: Props; } }}
const emptyTags = [ "area", "base", "br", "col", "embed", "hr", "img", "input", "keygen", "link", "meta", "param", "source", "track", "wbr",];
const booleanAttributes = [ "allowfullscreen", "async", "autofocus", "autoplay", "checked", "controls", "default", "defer", "disabled", "formnovalidate", "hidden", "inert", "ismap", "itemscope", "loop", "multiple", "muted", "nomodule", "novalidate", "open", "playsinline", "readonly", "required", "reversed", "selected",];

const escapeRegexp = /[&<>"]/;
// The `escapeToBuffer` implementation is based on code from the MIT licensed `react-dom` package.// https://github.com/facebook/react/blob/main/packages/react-dom/src/server/escapeTextForBrowser.jsconst escapeToBuffer = (str: string, buffer: string[]): void => { const match = str.search(escapeRegexp); if (match === -1) { buffer[0] += str; return; }
let escape; let index; let lastIndex = 0;
for (index = match; index < str.length; index++) { switch (str.charCodeAt(index)) { case 34: // " escape = "&quot;"; break; case 38: // & escape = "&amp;"; break; case 60: // < escape = "&lt;"; break; case 62: // > escape = "&gt;"; break; default: continue; }
buffer[0] += str.substring(lastIndex, index) + escape; lastIndex = index + 1; }
buffer[0] += str.substring(lastIndex, index);};
const childrenToStringToBuffer = ( children: Child[], buffer: string[],): void => { for (let i = 0, len = children.length; i < len; i++) { const child = children[i]; if (typeof child === "string") { escapeToBuffer(child, buffer); } else if ( typeof child === "boolean" || child === null || child === undefined ) { continue; } else if (child instanceof JSXNode) { child.toStringToBuffer(buffer); } else if ( typeof child === "number" || (child as unknown as { isEscaped: boolean }).isEscaped ) { buffer[0] += child; } else { // `child` type is `Child[]`, so stringify recursively childrenToStringToBuffer(child, buffer); } }};
export type FC<T = Props> = (props: T) => JSX.Element | null;
export class JSXNode { tag: string | CallableFunction; props: Props; children: Child[]; isEscaped: true = true; constructor(tag: string | CallableFunction, props: Props, children: Child[]) { this.tag = tag; this.props = props; this.children = children; }
toString(): string { const buffer: string[] = [""]; this.toStringToBuffer(buffer); return buffer[0]; }
toStringToBuffer(buffer: string[]): void { const tag = this.tag as string; const props = this.props; let { children } = this;
buffer[0] += `<${tag}`;
const propsKeys = Object.keys(props || {});
for (let i = 0, len = propsKeys.length; i < len; i++) { const v = props[propsKeys[i]]; if (typeof v === "string") { buffer[0] += ` ${propsKeys[i]}="`; escapeToBuffer(v, buffer); buffer[0] += '"'; } else if (typeof v === "number") { buffer[0] += ` ${propsKeys[i]}="${v}"`; } else if (v === null || v === undefined) { // Do nothing } else if ( typeof v === "boolean" && booleanAttributes.includes(propsKeys[i]) ) { if (v) { buffer[0] += ` ${propsKeys[i]}=""`; } } else if (propsKeys[i] === "dangerouslySetInnerHTML") { if (children.length > 0) { throw "Can only set one of `children` or `props.dangerouslySetInnerHTML`."; }
// deno-lint-ignore no-explicit-any const escapedString = new String(v.__html) as any; escapedString.isEscaped = true; children = [escapedString]; } else { buffer[0] += ` ${propsKeys[i]}="`; escapeToBuffer(v.toString(), buffer); buffer[0] += '"'; } }
buffer[0] += ">";
if (emptyTags.includes(tag as string)) { return; }
childrenToStringToBuffer(children, buffer);
buffer[0] += `</${tag}>`; }}
class JSXFunctionNode extends JSXNode { toStringToBuffer(buffer: string[]): void { const { children } = this;
// deno-lint-ignore ban-types const res = (this.tag as Function).call(null, { ...this.props, children: children.length <= 1 ? children[0] : children, });
if (res instanceof JSXNode) { res.toStringToBuffer(buffer); } else if (typeof res === "number" || res.isEscaped) { buffer[0] += res; } else { escapeToBuffer(res, buffer); } }}
class JSXFragmentNode extends JSXNode { toStringToBuffer(buffer: string[]): void { childrenToStringToBuffer(this.children, buffer); }}
export const h = ( tag: string | CallableFunction, props: Props, ...children: Child[]): JSX.Element => { if (typeof tag === "function") { return new JSXFunctionNode(tag, props, children); } else { return new JSXNode(tag, props, children); }};
export const Fragment = ( props: { key?: string; children?: Child[] },): JSX.Element => new JSXFragmentNode("", {}, props.children || []);