csv-stringify context.header bug repro

index.js

const { createWriteStream } = require('fs');
const intoStream = require('into-stream');
const csvStringify = require('csv-stringify');

const makePromise = () => {
  let resolve;
  let reject;
  const promise = new Promise((resolve_, reject_) => {
    resolve = resolve_;
    reject = reject_;
  });
  return { resolve, reject, promise };
};

async function saveAsCSV(fileName, collection) {
  const { resolve, reject, promise } = makePromise();
  let stream = intoStream.object(collection);
  stream.pipe(csvStringify({
    header: true, // setting this to false prevents the problem but also prevents the header row from being generated
    cast: {
      number(original, context) {
        const { header } = context;
        console.log(`header=${header} for context -->`, context);
        return { value: `${original}${header ? '-header' : ''}` };
      }
    },
    columns: [{
      key: 'foo',
      header: 'The foo column'
   }, {
      key: 'bar',
      header: 'The bar column'
    }]
  }))
  .pipe(createWriteStream(fileName))
  .on('finish', () => {
    console.log(`saveAsCSV write stream finished for ${fileName}`);
    resolve();
  })
  .on('error', reject);
  return promise;
}

async function main() {
  const records = [{
    foo: 1,
    bar: 2,
  }, {
    foo: 3,
    bar: 4,
  }];
  await saveAsCSV('output.csv', records)
}

if (require.main === module) {
  main();
}

package.json

{
  "name": "csv-header-test",
  "version": "1.0.0",
  "description": "Repro of what appears to be a bug with csv-stringify",
  "main": "index.js",
  "scripts": {
    "test": "echo \"Error: no test specified\" && exit 1"
  },
  "author": "Jacob Quant <[email protected]>",
  "license": "MIT",
  "dependencies": {
    "csv-stringify": "^5.3.4",
    "into-stream": "^5.1.1"
  }
}