By making sure the _events is always an object there is one less check
that needs to be performed by emit.
Use undefined instead of null. typeof checks are a lot faster than
isArray.
There are a few places where the this._events check cannot be removed
because it is possible for the user to call those methods after using
utils.extend to create their own EventEmitter, but before it has
actually been instantiated.
Unnecessary checks were being performed on if the event existed before
being removed.
_events starts out as null, so reset to null when emptied.
Checking typeof is a lot cheaper than isArray().
Ability to return just the length of listeners for a given type, using
EventEmitter.listenerCount(emitter, event). This will be a lot cheaper
than creating a copy of the listeners array just to check its length.
Unfortunately, it's just too slow to do this in events.js. Users will
just have to live with not having events named __proto__ or toString.
This reverts commit b48e303af0.
While it's true that error objects have a history of getting snake_case
properties attached by the host system, it's a point of confusion to
Node users that comes up a lot. It's still 'experimental', so best to
change this sooner rather than later.
Always add domain, _events, and _maxListeners properties, set to the
default values at first.
Leads to a very very slight perf improvement when using setMaxListeners,
or dealing with a lot of EE objects that don't have any listeners.
This addresses #4034. There are two problems happening:
1. The domain is not exited automatically when calling dispose() on it.
Then, since the domain is disposed, attempting to exit it again will do
nothing.
2. The active domain is stored on process.domain. Since thrown errors
call `process.emit('uncaughtException', er)`, and the process is an
event emitter with a `.domain` member, it re-enters the domain a second
time before calling the error handler, pushing it onto the stack again.
Thus, if the handler calls `domain.dispose()`, then the domain is now on
the stack twice, and cannot be exited properly. Since the domain is
disposed, any subsequent IO will be no-op'ed, since we've declared that
this context is done and best forgotten.
The solution here is twofold:
1. In EventEmitter.emit, do not enter the domain if `this===process`.
2. Automatically exit the domain when calling `domain.dispose()`.
This reverts commit 928ea564d1.
Keeping the original Array instance in-place essentially causes a memory leak
on EventEmitters that use an infinite number of event names (an incrementing
counter, for example), which isn't an unreasonable thing to want to do.
Fixes#3702.
When removeAllListeners is called, the listeners array
is deleted to maintain compatibility with v0.6.
Reverts "events: don't delete the listeners array"
This reverts commit 78dc13fbf9.
Conflicts:
test/simple/test-event-emitter-remove-all-listeners.js
This is a squashed commit of the main work done on the domains-wip branch.
The original commit messages are preserved for posterity:
* Implicitly add EventEmitters to active domain
* Implicitly add timers to active domain
* domain: add members, remove ctor cb
* Don't hijack bound callbacks for Domain error events
* Add dispose method
* Add domain.remove(ee) method
* A test of multiple domains in process at once
* Put the active domain on the process object
* Only intercept error arg if explicitly requested
* Typo
* Don't auto-add new domains to the current domain
While an automatic parent/child relationship is sort of neat,
and leads to some nice error-bubbling characteristics, it also
results in keeping a reference to every EE and timer created,
unless domains are explicitly disposed of.
* Explicitly adding one domain to another is still fine, of course.
* Don't allow circular domain->domain memberships
* Disposing of a domain removes it from its parent
* Domain disposal turns functions into no-ops
* More documentation of domains
* More thorough dispose() semantics
* An example using domains in an HTTP server
* Don't handle errors on a disposed domain
* Need to push, even if the same domain is entered multiple times
* Array.push is too slow for the EE Ctor
* lint domain
* domain: docs
* Also call abort and destroySoon to clean up event emitters
* domain: Wrap destroy methods in a try/catch
* Attach tick callbacks to active domain
* domain: Only implicitly bind timers, not explicitly
* domain: Don't fire timers when disposed.
* domain: Simplify naming so that MakeCallback works on Timers
* Add setInterval and nextTick to domain test
* domain: Make stack private
There are a few kinds of errors that are very confusing.
1. Errors raised in nextTick
2. Errors emitted on the "error" event
3. RangeErrors that crash the program (or anything without a stack trace)
Long traces will make make these better, of course. In the meantime, this
adds a few handy signposts (in the form of better error reporting and
comments on the otherwise inscrutable code printed to the terminal) that can
help new users find the cause, or at least, ask for help more effectively.
Trevor Norris
isaacs
Ryunosuke SATO
Ben Noordhuis
Joe Andaverde
Nathan Rajlich
Maciej Małecki
Reid Burke
Roly Fentanes
Siddharth Mahendraker
Ryan Dahl
koichik
Felix Geisendörfer
Arnout Kazemier
Aaron Heckmann
Daniel C
Jeremy Martin
Peteris Krumins
Micheil Smith
Joshaven Potter