Monkey patches webpack/tapable with some debug information

trackable.js

var Tapable = require("tapable");

Tapable.prototype.plugin = function plugin(name, fn) {
  if(Array.isArray(name)) {
    name.forEach(function(name) {
      this.plugin(name, fn);
    }, this);
    return;
  }

  register(name, this);

  if(!this._plugins[name]) this._plugins[name] = [fn];
  else this._plugins[name].push(fn);
};

Tapable.prototype.applyPlugins = wrapSync(Tapable.prototype.applyPlugins);
Tapable.prototype.applyPluginsWaterfall = wrapSync(Tapable.prototype.applyPluginsWaterfall);
Tapable.prototype.applyPluginsBailResult = wrapSync(Tapable.prototype.applyPluginsBailResult);
Tapable.prototype.applyPluginsAsyncSeries = Tapable.prototype.applyPluginsAsync = wrapAsync(Tapable.prototype.applyPluginsAsyncSeries);
Tapable.prototype.applyPluginsAsyncSeriesBailResult = wrapAsync(Tapable.prototype.applyPluginsAsyncSeriesBailResult);
Tapable.prototype.applyPluginsAsyncWaterfall = wrapAsync(Tapable.prototype.applyPluginsAsyncWaterfall);
Tapable.prototype.applyPluginsParallel = wrapAsync(Tapable.prototype.applyPluginsParallel);
Tapable.prototype.applyPluginsParallelBailResult = wrapAsync(Tapable.prototype.applyPluginsParallelBailResult);

var stack = [];

function taplog() {
  var prefix = '   '.repeat(stack.length);
  var args = Array.prototype.slice.call(arguments);
  args.unshift(prefix);
  console.log.apply(console, args);
}

function pushstack(name) {
  taplog("entering '" + name + "'");
  stack.push(name);

  if (name === 'seal') {
    debugger;
  }
}

function popstack() {
  var name = stack.pop();
  taplog("leaving '" + name + "'");
}

function wrapSync(fn) {
  return function wrappedSync(name) {
    pushstack(name);
    var args = Array.prototype.slice.call(arguments);
    var rv = fn.apply(this, args);
    popstack();
    return rv;
  }
}

function wrapAsync(fn) {
  return function wrappedAsync(name) {
    pushstack(name);
    var args = Array.prototype.slice.call(arguments);
    var originalCallback = args[args.length - 1];
    args[args.length - 1] = function wrappedCallback() {
      popstack();
      var cbargs = Array.prototype.slice.call(arguments);
      originalCallback.apply(this, cbargs);
    }
    fn.apply(this, args);
  }
}

function register(name, target) {
  var stack = getStack();
  var frameIndex = 2;
  var thisFilename = stack[0].getFileName();
  while (stack[frameIndex].getFileName() == thisFilename) {
    frameIndex += 1;
  }

  taplog(
    "registering", "'" + name + "'",
    "on", target.constructor.name,
    "from", stack[frameIndex].getFileName()
  );
}

function getStack() {
  var orig = Error.prepareStackTrace;
  Error.prepareStackTrace = function(_, stack) {
    return stack;
  };
  var err = new Error;
  Error.captureStackTrace(err, arguments.callee);
  var stack = err.stack;
  Error.prepareStackTrace = orig;
  return stack;
}