nstdlib-nightly/lib/internal/navigator.mjs

Node.js standard library converted to runtime-agnostic ES modules.

// Source: https://github.com/nodejs/node/blob/65eff1eb/lib/internal/navigator.js

import { codes as __codes__ } from "nstdlib/lib/internal/errors";
import { kEnumerableProperty } from "nstdlib/lib/internal/util";
import { getAvailableParallelism } from "nstdlib/stub/binding/os";
import {
  platform,
  arch,
  version as nodeVersion,
} from "nstdlib/lib/internal/process/per_thread";
import { language } from "nstdlib/stub/binding/config";

const { ERR_ILLEGAL_CONSTRUCTOR } = __codes__;

const kInitialize = Symbol("kInitialize");

/**
 * @param {string} arch
 * @param {string} platform
 * @returns {string}
 */
function getNavigatorPlatform(arch, platform) {
  if (platform === "darwin") {
    // On macOS, modern browsers return 'MacIntel' even if running on Apple Silicon.
    return "MacIntel";
  } else if (platform === "win32") {
    // On Windows, modern browsers return 'Win32' even if running on a 64-bit version of Windows.
    // https://developer.mozilla.org/en-US/docs/Web/API/Navigator/platform#usage_notes
    return "Win32";
  } else if (platform === "linux") {
    if (arch === "ia32") {
      return "Linux i686";
    } else if (arch === "x64") {
      return "Linux x86_64";
    }
    return `Linux ${arch}`;
  } else if (platform === "freebsd") {
    if (arch === "ia32") {
      return "FreeBSD i386";
    } else if (arch === "x64") {
      return "FreeBSD amd64";
    }
    return `FreeBSD ${arch}`;
  } else if (platform === "openbsd") {
    if (arch === "ia32") {
      return "OpenBSD i386";
    } else if (arch === "x64") {
      return "OpenBSD amd64";
    }
    return `OpenBSD ${arch}`;
  } else if (platform === "sunos") {
    if (arch === "ia32") {
      return "SunOS i86pc";
    }
    return `SunOS ${arch}`;
  } else if (platform === "aix") {
    return "AIX";
  }
  return `${String.prototype.toUpperCase.call(platform[0])}${String.prototype.slice.call(platform, 1)} ${arch}`;
}

class Navigator {
  // Private properties are used to avoid brand validations.
  #availableParallelism;
  #userAgent;
  #platform;
  #languages;

  constructor() {
    if (arguments[0] === kInitialize) {
      return;
    }
    throw new ERR_ILLEGAL_CONSTRUCTOR();
  }

  /**
   * @return {number}
   */
  get hardwareConcurrency() {
    this.#availableParallelism ??= getAvailableParallelism();
    return this.#availableParallelism;
  }

  /**
   * @return {string}
   */
  get language() {
    return language;
  }

  /**
   * @return {Array<string>}
   */
  get languages() {
    this.#languages ??= Object.freeze([this.language]);
    return this.#languages;
  }

  /**
   * @return {string}
   */
  get userAgent() {
    this.#userAgent ??= `Node.js/${String.prototype.slice.call(nodeVersion, 1, String.prototype.indexOf.call(nodeVersion, "."))}`;
    return this.#userAgent;
  }

  /**
   * @return {string}
   */
  get platform() {
    this.#platform ??= getNavigatorPlatform(arch, platform);
    return this.#platform;
  }
}

Object.defineProperties(Navigator.prototype, {
  hardwareConcurrency: kEnumerableProperty,
  language: kEnumerableProperty,
  languages: kEnumerableProperty,
  userAgent: kEnumerableProperty,
  platform: kEnumerableProperty,
});

export { getNavigatorPlatform };
const _export_navigator_ = new Navigator(kInitialize);
export { _export_navigator_ as navigator };
export { Navigator };