Remove flow types from all js and jsx files

removeFlowTypes.js

const fs = require('fs');
const glob = require('glob-fs')();
const flowRemoveTypes = require('flow-remove-types');
const firstline = require('firstline');
 
const files = glob.readdirSync('src/**/@(**.js|**.jsx)', {}); 

files.forEach(async (file) => {
  console.log(`Found file ${file}, checking if it has flow annotion on first line`);
  const hasFlowAnnotation = await firstline(file);

  if (hasFlowAnnotation.includes('@flow')) {
    console.log(`The file ${file} has a flow annotation, removing all types`);
    const fileToRemoveTypes = fs.readFileSync(file, 'utf-8');
    const output = flowRemoveTypes(fileToRemoveTypes);

    console.log(`Writing temporary file as ${file}.$$`);
    fs.writeFileSync(`${file}.$$`, output.toString());

    console.log(`Renaming file back to ${file}`);
    fs.rename(`${file}.$$`, file, (err) => {
      if (err) {
        console.log(`Error renaming file ${file}.$$`, err);
      } else {
        console.log(`File ${file}.$$ successfuly renamed to ${file}`);
      }
    })
  } else {
    console.log(`The file ${file} does not have a flow annotation, skipping`);
  }
})