@whimco/chisel-cli/lib/emitSentinel.js

// lib/emitSentinel.js
const fs = require("fs");
const path = require("path");
const crypto = require("crypto");

function writeIfChanged(file, content) {
  if (fs.existsSync(file) && fs.readFileSync(file, "utf8") === content) return false;
  fs.mkdirSync(path.dirname(file), { recursive: true });
  fs.writeFileSync(file, content);
  return true;
}

function emit(manifestJson, sentinelRel = "src/chisel/__generated__/manifest-hash.ts") {
  const hash = crypto.createHash("sha1").update(JSON.stringify(manifestJson)).digest("hex").slice(0, 8);
  const file = path.join(process.cwd(), sentinelRel);
  const content = `// Auto-generated by Chisel. Do not edit.
export const CHISEL_MANIFEST_HASH = "${hash}" as const;
`;
  return writeIfChanged(file, content);
}

module.exports = { emit };