TODO/XXX/FIXME comments in lib directory #4642

  // Just to spin-off events
  // TODO(indutny): Figure out why node.cc isn't doing this
  setImmediate(function() {
  });

  var self = this;

  // TODO: We have a cache of handle's we've already seen in this.handles
  // This can be used if we're careful.
  var req = {
...

// reqBacktrace(cb)
// TODO: from, to, bottom
Client.prototype.reqBacktrace = function(cb) {
  this.req({ command: 'backtrace', arguments: { inlineRefs: true } }, cb);
...

// reqSetExceptionBreak(type, cb)
// TODO: from, to, bottom
Client.prototype.reqSetExceptionBreak = function(type, cb) {
  this.req({
...
  this.pause();

  // XXX Need to figure out why we need this delay
  setTimeout(function() {

...
  self.killChild();

  // XXX need to wait a little bit for the restart to work?
  setTimeout(function() {
    self.trySpawn();

      socket.removeListener('error', socketErrorListener);

      // TODO(isaacs): Need a way to reset a stream to fresh state
      // IE, not flowing, and not explicitly paused.
      socket._readableState.flowing = null;

}

// XXX This is a mess.
// TODO: http.Parser should be a Writable emits request/response events.
function parserOnBody(b, start, len) {
  var parser = this;
...
// Free the parser and also break any links that it
// might have to any other things.
// TODO: All parser data should be attached to a
// single object, so that it can be easily cleaned
// up by doing `parser.data = {}`, which should

  Stream.Readable.call(this);

  // XXX This implementation is kind of all over the place
  // When the parser emits body chunks, they go in this list.
  // _read() pulls them out, and when it finds EOF, it ends.

  parser[kOnExecute] = onParserExecute;

  // TODO(isaacs): Move all these functions out of here
  function socketOnError(e) {
    // Ignore further errors
...
        var bodyHead = d.slice(bytesParsed, d.length);

        // TODO(isaacs): Need a way to reset a stream to fresh state
        // IE, not flowing, and not explicitly paused.
        socket._readableState.flowing = null;

function writeAfterEnd(stream, cb) {
  var er = new Error('write after end');
  // TODO: defer error events consistently everywhere, not just the cb
  stream.emit('error', er);
  process.nextTick(cb, er);
...

    // count the one we are adding, as well.
    // TODO(isaacs) clean this up
    state.pendingcb++;
    state.lastBufferedRequest = null;

    c.infoAccess = {};

    // XXX: More key validation?
    info.replace(/([^\n:]*):([^\n]*)(?:\n|$)/g, function(all, key, val) {
      if (key === '__proto__')

  // side.
  //
  // TODO(indutny): Remove magic number, use watermark based limits
  if (!this._resumingSession &&
      this._opposite._internallyPendingBytes() < 128 * 1024) {
...

CryptoStream.prototype._read = function read(size) {
  // XXX: EOF?!
  if (!this.pair.ssl) return this.push(null);

      return cb(new Error('Socket is closed'));

    // TODO(indutny): eventually disallow raw `SecureContext`
    if (context)
      self._handle.sni_context = context.context || context;
...
  // lib/net.js expect this value to be non-zero if write hasn't been flushed
  // immediately
  // TODO(indutny): rewise this solution, it might be 1 before handshake and
  // represent real writeQueueSize during regular writes.
  ssl.writeQueueSize = 1;
...
};

// TODO: support anonymous (nocert) and PSK

// TODO(trevnorris): fix these checks to follow new standard
// write(string, offset = 0, length = buffer.length, encoding = 'utf8')
var writeWarned = false;
...
    }

  // XXX legacy write(string, encoding, offset, length) - remove in v0.13
  } else {
    writeWarned = internalUtil.printDeprecationMessage(writeMsg, writeWarned);
...


// TODO(trevnorris): currently works like Array.prototype.slice(), which
// doesn't follow the new standard for throwing on out of range indexes.
Buffer.prototype.slice = function slice(start, end) {

  this.errno = 0;

  // FIXME(bnoordhuis) Polymorphic return type for lack of a better solution.
  var rval;
  if (addressType === 'udp4' || addressType === 'udp6')
...
      var out = {};
      self.handle.getsockname(out);
      // TODO(bnoordhuis) Check err.
      send(null, { sockname: out }, null);
    } else {
...
  cluster.settings = {};

  // XXX(bnoordhuis) Fold cluster.schedulingPolicy into cluster.settings?
  var schedulingPolicy = {
    'none': SCHED_NONE,
...

  if (schedulingPolicy === undefined) {
    // FIXME Round-robin doesn't perform well on Windows right now due to the
    // way IOCP is wired up. Bert is going to fix that, eventually.
    schedulingPolicy = (process.platform === 'win32') ? SCHED_NONE : SCHED_RR;
...
  // Keyed on address:port:etc. When a worker dies, we walk over the handles
  // and remove() the worker from each one. remove() may do a linear scan
  // itself so we might end up with an O(n*m) operation. Ergo, FIXME.
  const handles = require('internal/cluster').handles;

...
    var key = message.key;
    function listen(backlog) {
      // TODO(bnoordhuis) Send a message to the master that tells it to
      // update the backlog size. The actual backlog should probably be
      // the largest requested size by any worker.
...
    }

    // XXX(bnoordhuis) Probably no point in implementing ref() and unref()
    // because the control channel is going to keep the worker alive anyway.
    function ref() {

Console.prototype.trace = function trace() {
  // TODO probably can to do this better with V8's debug object once that is
  // exposed.
  var err = new Error();

function errnoException(err, syscall, hostname) {
  // FIXME(bnoordhuis) Remove this backwards compatibility nonsense and pass
  // the true error to the user. ENOTFOUND is not even a proper POSIX error!
  if (err === uv.UV_EAI_MEMORY ||

  // ignore errors on disposed domains.
  //
  // XXX This is a bit stupid.  We should probably get rid of
  // domain.dispose() altogether.  It's almost always a terrible
  // idea.  --isaacs

  channel.buffering = false;
  channel.onread = function(nread, pool, recvHandle) {
    // TODO(bnoordhuis) Check that nread > 0.
    if (pool) {
      jsonBuffer += decoder.write(pool);
...
      process.nextTick(callback, ex);
    } else {
      this.emit('error', ex);  // FIXME(bnoordhuis) Defer to next tick.
    }
    return false;
...
        process.nextTick(callback, ex);
      } else {
        this.emit('error', ex);  // FIXME(bnoordhuis) Defer to next tick.
      }
    }

module.exports.createInternalRepl = createRepl;

// XXX(chrisdickinson): The 15ms debounce value is somewhat arbitrary.
// The debounce is to guard against code pasted into the REPL.
const kDebounceHistoryMS = 15;
...
    opts.historySize = historySize;
  } else {
    // XXX(chrisdickinson): set here to avoid affecting existing applications
    // using repl instances.
    opts.historySize = 1000;

};

// TODO(bnoordhuis) Unused, remove in the future.
Module.requireRepl = internalUtil.deprecate(function() {
  return NativeModule.require('internal/repl');

// up.
function onSocketEnd() {
  // XXX Should not have to do as much crap in this function.
  // ended should already be true, since this is called *after*
  // the EOF errno and onread has eof'ed
...
  er.code = 'EPIPE';
  var self = this;
  // TODO: defer error events consistently everywhere, not just the cb
  self.emit('error', er);
  if (typeof cb === 'function') {
...
    var out = {};
    var err = this._handle.getpeername(out);
    if (err) return {};  // FIXME(bnoordhuis) Throw?
    this._peername = out;
  }
...
    var out = {};
    var err = this._handle.getsockname(out);
    if (err) return {};  // FIXME(bnoordhuis) Throw?
    this._sockname = out;
  }
...

function connect(self, address, port, addressType, localAddress, localPort) {
  // TODO return promise from Socket.prototype.connect which
  // wraps _connectReq.

...

  // If host is an IP, skip performing a lookup
  // TODO(evanlucas) should we hot path this for localhost?
  var addressType = exports.isIP(host);
  if (addressType) {
...

    // It's possible we were destroyed while looking this up.
    // XXX it would be great if we could cancel the promise returned by
    // the look up.
    if (!self._connecting) return;
...

  // Update handle if it was wrapped
  // TODO(indutny): assert that the handle is actually an ancestor of old one
  handle = self._handle;

...
    // port before calling listen().
    //
    // FIXME(bnoordhuis) Doesn't work for pipe handles, they don't have a
    // getsockname() method. Non-issue for now, the cluster module doesn't
    // really support pipes anyway.
...
    var out = {};
    this._handle.getsockname(out);
    // TODO(bnoordhuis) Check err and throw?
    return out;
  } else if (this._pipeName) {

  var f = win32SplitPath(path)[2];
  // TODO: make this comparison case-insensitive on windows?
  if (ext && f.substr(-1 * ext.length) === ext) {
    f = f.substr(0, f.length - ext.length);

  }

  // TODO support returning arbitrary buffers.

  return out.slice(0, outIndex - 1);

    if (err) {
      // XXX Log it somewhere?
      return;
    }

  // save the line so I can do magic later
  if (cmd) {
    // TODO should I tab the level?
    const len = self.lines.level.length ? self.lines.level.length - 1 : 0;
    self.lines.push('  '.repeat(len) + cmd);
...
    // if the REPL still has a bufferedCommand and
    // self.lines.level.length === 0
    // TODO? keep a log of level so that any syntax breaking lines can
    // be cleared on .break and in the case of a syntax error?
    // TODO? if a log was kept, then I could clear the bufferedComand and
    // eval these lines and throw the syntax error
  } else {

// characters. CESU-8 is handled as part of the UTF-8 encoding.
//
// @TODO Handling all encodings inside a single object makes it very difficult
// to reason about this code, so it should be split up in the future.
// @TODO There should be a utf8-strict encoding that rejects invalid UTF-8 code
// points as used by CESU-8.
const StringDecoder = exports.StringDecoder = function(encoding) {
...
    // See http://en.wikipedia.org/wiki/UTF-8#Description

    // 110XXXXX
    if (i === 1 && c >> 5 === 0x06) {
      this.charLength = 2;
...
    }

    // 1110XXXX
    if (i <= 2 && c >> 4 === 0x0E) {
      this.charLength = 3;
...
    }

    // 11110XXX
    if (i <= 3 && c >> 3 === 0x1E) {
      this.charLength = 4;

    // http://a@b?@c => user:a host:b path:/?@c

    // v0.12 TODO(isaacs): This is not quite how Chrome does things.
    // Review our test case against browsers more comprehensively.