projenrc-js-2-ts.js

#!/usr/bin/env node

const { spawnSync } = require("node:child_process");
const fs = require("node:fs");
const path = require("node:path");

const spawny = (command) => {
  const [cmd, ...rest] = command.split(" ");
  console.log(command);
  spawnSync(cmd, rest, { stdio: 'inherit', cwd: process.cwd() });
}
const npxProjen = () => spawny('npx projen default')

const rcJsName = process.argv.slice(2).at(0) ?? ".projenrc.js";
const rcTsName = '.projenrc.ts';
const rcFilePath = path.join(process.cwd(), rcJsName);

/**
 * Add projenrcTs: true to your project. 
 */
const rcFileBuffer = fs.readFileSync(rcFilePath, { encoding: 'utf8' }).split('\n');
const nameLine = rcFileBuffer.findIndex((l) => l.match(/name\:.*,/))
rcFileBuffer.splice(nameLine + 1, 0, '  projenrcTs: true,')

fs.writeFileSync(rcFilePath, rcFileBuffer.join('\n'));

/**
 * Run npx projen.
 */
npxProjen();

/**
 * Rename .projenrc.js to .projenrc.ts.
 */
const newRcFilePath = path.join(process.cwd(), rcTsName);
fs.renameSync(rcFilePath, newRcFilePath);

/**
 * Update requires to imports.
 */
spawny(`npx --yes [email protected] ${rcTsName}`)

/**
 * Run npx projen.
 */
npxProjen();