Revive a JavaScript stacktrace string with local available source maps.

stacktrace.js

const fs = require('fs');
const retrace = require('retrace'); // yarn add retrace
const path = require('path');

retrace.resolve = uri => {
  // assumes that source maps are in the same directory as this script, but in
  // a `maps` folder:
  return readFile(path.join(__dirname, 'maps', `${path.basename(uri)}.map`));
};

function readFile(file) {
  return new Promise((resolve, reject) => {
    fs.readFile(file, { encoding: 'utf-8' }, (err, content) => {
      if (err) {
        reject(err);
        return;
      }
      resolve(content);
    });
  });
}

// Usage: Call exported function and pass the stacktrace string with proper new line
// characters.
// Caveat: Anonymous stack frames are omitted in the output.
module.exports = stack => {
  const withoutAnonymousFrames = stack.replace(/(\n.*\<anonymous\>.*\n)/g, '');
  return retrace.map(withoutAnonymousFrames)
};