An API version of `npx htmlhint --rules=tag-pair --nocolor **/*.ftl`

ftl-lint.js

import fs from "node:fs/promises";
import glob from "fast-glob";
import {HTMLHint} from "htmlhint";

const res = await verifyGlob("**/*.ftl", false);
console.log(res);

async function verifyGlob(fileglob, ignoreComments=true) {
  let errors = [];
  for (const file of await glob([fileglob, "!node_modules/**"])) {
    errors = errors.concat(await verifyFtl(file, ignoreComments));
    process.errorCode = 1;
  }
  return errors;
}

async function verifyFtl(filename, ignoreComments=true) {
  let ftl = await fs.readFile(filename, "utf-8");
  if (ignoreComments) {
    ftl = $ignoreComments(ftl);
  }
  return HTMLHint.verify(ftl, {"tag-pair": true})
    .map(err => Object.assign(err, {filename}));
}

function $ignoreComments(str="") {
  return str.split("\n")
    .map(line => {
      if (!line.trim().startsWith("#")) {
        return line;
      }
      // Return a "fake" line so our line numbers match up; but this should effectively ignore any .ftl comments.
      return "# (comment removed)";
    })
    .join("\n");
}