findAndReplace.js

const exec = require('child_process').exec

exec("npm --save uninstall react react-dom", (err, o) => {
  console.log(err, o);
})

exec("npm --save install preact preact-compat", (err, o) => {
  console.log(err, o);
})

function stringExists(options, callback) {
  console.log('grep -rl "' + options.searchString + '" ' + options.filePattern)
  exec('grep -rl "' + options.searchString + '" ' + options.filePattern, (err, o) => {
    // console.log(err, o)
    callback(o !== '')
  })
}

function findReplaceInFiles(options, callback) {
  // find ./node_modules/react-scripts/config/*.config.* -type f -exec sed -i 's/alias: {/alias: {\n			\'react\': \'preact-compat\',\n			\'react-dom\': \'preact-compat\',/gi' {} ;
  console.log("find " + options.filePattern + " -type f -exec sed -i \"s/" + options.searchString + "/" + options.replaceString + "/gi\" {} \\;");
  return exec("find " + options.filePattern + " -type f -exec sed -i \"s/" + options.searchString + "/" + options.replaceString + "/gi\" {} \\;", callback)
}

stringExists({
  filePattern: './node_modules/react-scripts/config/',
  searchString: 'preact-compat',
},
(bool) => {
  console.log(bool);
  // if (!bool) {
    findReplaceInFiles({
      filePattern: './node_modules/react-scripts/config/*.config.*',
      searchString: 'alias: {',
      replaceString: "alias: {\\n\\t\\t\\t\\'react\\': \\'preact-compat\\',\\n\\t\\t\\t\\'react-dom\\': \\'preact-compat\\',"
    }, (err, o) => {
      console.log(err, o)
    })
  // }
})