Who calls `path.exists`?

trace.js

#!/usr/bin/env node
function trace(base) {
  return function() {
    console.log('called at:', new Error().stack.split('\n')[2].trim());
    return base.apply(this, arguments);
  };
}

var path = require('path');
path.exists = trace(path.exists);
path.existsSync = trace(path.existsSync);

Put this at the beginning of your node app's index file and you should see the call site