verbose logging of nodejs async function by converting to generator

VerboseAsync.js

async function myAsyncFunction() {
   await callToSomethingAsync();
   someNonAsyncFunctionCall();
   await callToAnotherAsyncThing();
}

function convertAsyncFunctionToGenerator(fn) {
  // Convert the function to string
  let stringFn = fn.toString();

  // Carefully replace 'async function' with 'function*'
  // This pattern looks for 'async function' declarations, considering spaces and avoiding partial matches like 'asyncFunction'
  stringFn = stringFn.replace(/async function/g, "function*");

  // Replace 'await' with 'yield'
  stringFn = stringFn.split("await").join("yield");

  try {
    // Attempt to eval the transformed string into a function
    // Note: This approach has limitations and might not work for all functions, especially those relying on external scope or complex contexts
    const genFunc = eval(`(${stringFn})`);
    return genFunc;
  } catch (e) {
    console.error("Conversion failed:", e);
    return null;
  }
}

async function debugAsyncFunction(asyncFunction) {
  const generatorFunction = convertAsyncFunctionToGenerator(asyncFunction);
  const iterator = generatorFunction();

  let result = iterator.next();
  let i = 1;
  while (!result.done) {
    result = await result.value; // Await the yielded promise
    console.log(`> await ${generatorFunction.toString().split("yield")[i].split("\n")[0]}`);
    result = iterator.next(result);
    i++;
  }
}

// Usage
debugAsyncFunction(myAsyncFunction);
// Will console.log
//>   await callToSomethingAsync();
//>   await callToAnotherAsyncThing();
// Helping you figure out when each of your async things are getting called