lighthouse/core/audits/dobetterweb/js-libraries.js

Automated auditing, performance metrics, and best practices for the web.

/**
 * @license
 * Copyright 2017 Google LLC
 * SPDX-License-Identifier: Apache-2.0
 */

/**
 * @fileoverview Diagnostic audit that lists all JavaScript libraries detected on the page
 */


import {Audit} from '../audit.js';
import * as i18n from '../../lib/i18n/i18n.js';

const UIStrings = {
  /** Title of a Lighthouse audit that provides detail on the Javascript libraries that are used on the page. */
  title: 'Detected JavaScript libraries',
  /** Description of a Lighthouse audit that tells the user what this audit is detecting. This is displayed after a user expands the section to see more. No character length limits. */
  description: 'All front-end JavaScript libraries detected on the page. [Learn more about this JavaScript library detection diagnostic audit](https://developer.chrome.com/docs/lighthouse/best-practices/js-libraries/).',
  /** Label for a column in a data table; entries will be the version numbers of the detected Javascript libraries.  */
  columnVersion: 'Version',
};

const str_ = i18n.createIcuMessageFn(import.meta.url, UIStrings);

class JsLibrariesAudit extends Audit {
  /**
   * @return {LH.Audit.Meta}
   */
  static get meta() {
    return {
      id: 'js-libraries',
      title: str_(UIStrings.title),
      scoreDisplayMode: Audit.SCORING_MODES.INFORMATIVE,
      description: str_(UIStrings.description),
      requiredArtifacts: ['Stacks'],
    };
  }

  /**
   * @param {LH.Artifacts} artifacts
   * @return {LH.Audit.Product}
   */
  static audit(artifacts) {
    const libDetails = artifacts.Stacks
      .filter(stack => stack.detector === 'js')
      // Don't show the fast paths in the table.
      .filter(stack => !stack.id.endsWith('-fast'))
      .map(stack => ({
        name: stack.name,
        version: stack.version,
        npm: stack.npm,
      }));

    /** @type {LH.Audit.Details.Table['headings']} */
    const headings = [
      {key: 'name', valueType: 'text', label: str_(i18n.UIStrings.columnName)},
      {key: 'version', valueType: 'text', label: str_(UIStrings.columnVersion)},
    ];
    const details = Audit.makeTableDetails(headings, libDetails);

    const debugData = {
      type: /** @type {const} */ ('debugdata'),
      stacks: artifacts.Stacks.map(stack => {
        return {
          id: stack.id,
          version: stack.version,
        };
      }),
    };

    if (!libDetails.length) {
      return {score: null, notApplicable: true};
    }

    return {
      score: 1, // Always pass for now.
      details: {
        ...details,
        debugData,
      },
    };
  }
}

export default JsLibrariesAudit;
export {UIStrings};