markdownlint/lib/md059.mjs

// @ts-check

import { addErrorContext } from "../helpers/helpers.cjs";
import { filterByTypesCached } from "./cache.mjs";

const defaultBannedText = [
  "click here",
  "here",
  "learn more",
  "link",
  "more",
  "read more"
];

/**
 * Normalizes a string and removes extra whitespaces and punctuations.
 *
 * @param {string} text String to transform.
 * @returns {string} Normalized string with no punctuations or extra whitespaces.
 */
function normalizeText(text) {
  return text
    .toLowerCase()
    .replace(/\W+/g, " ")
    .replace(/\s+/g, " ")
    .trim();
}

/** @type {import("markdownlint").Rule} */
export default {
  "names": [ "MD059", "descriptive-link-text" ],
  "description": "Link text should be descriptive",
  "tags": [ "links", "accessibility" ],
  "parser": "micromark",
  "function": function MD059(params, onError) {
    const bannedNames = new Set(params.config.link_texts || defaultBannedText);
    const labels = filterByTypesCached([ "label" ])
      .filter((label) => label.parent?.type === "link");

    for (const label of labels) {
      const labelTexts = label.children.filter((child) => child.type === "labelText");
      for (const labelText of labelTexts) {
        const { text } = label;
        if (bannedNames.has(normalizeText(text))) {
          const range = labelText.startLine === labelText.endLine ?
            [ labelText.startColumn, text.length ] :
            undefined;
          addErrorContext(
            onError,
            labelText.startLine,
            text,
            undefined,
            undefined,
            range
          );
        }
      }
    }
  }
};