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import { notImplemented } from "../notImplemented.ts";
// TODO: given we are now duplicating loadUrl,// we should instead cache and re-using in the// load() for the plugin.
/** * exists * * @param {URL} url * @param {RequestInit} [fetchOpts] * @returns {Promise<boolean>} * @private */export async function exists(  url: URL,  fetchOpts?: RequestInit,): Promise<boolean> | never {  switch (url.protocol) {    case "file:": {      try {        const { isFile } = await Deno.stat(url);
        return isFile;      } catch {        return false;      }    }    case "http:":    case "https:": {      try {        const res = await fetch(url.href, fetchOpts);
        // Prevent leaking fetchResponseBody resource        await res.arrayBuffer();
        return res.ok;      } catch {        return false;      }    }    default: {      return notImplemented(`support for protocol '${url.protocol}'`);    }  }}