rxjs
Version:
Reactive Extensions for modern JavaScript
140 lines • 4.67 kB
JavaScript
import { isArray } from './util/isArray';
import { isObject } from './util/isObject';
import { isFunction } from './util/isFunction';
import { UnsubscriptionError } from './util/UnsubscriptionError';
export class Subscription {
constructor(unsubscribe) {
this.closed = false;
this._parent = null;
this._parents = null;
this._subscriptions = null;
if (unsubscribe) {
this._unsubscribe = unsubscribe;
}
}
unsubscribe() {
let hasErrors = false;
let errors;
if (this.closed) {
return;
}
let { _parent, _parents, _unsubscribe, _subscriptions } = this;
this.closed = true;
this._parent = null;
this._parents = null;
this._subscriptions = null;
let index = -1;
let len = _parents ? _parents.length : 0;
while (_parent) {
_parent.remove(this);
_parent = ++index < len && _parents[index] || null;
}
if (isFunction(_unsubscribe)) {
try {
_unsubscribe.call(this);
}
catch (e) {
hasErrors = true;
errors = e instanceof UnsubscriptionError ? flattenUnsubscriptionErrors(e.errors) : [e];
}
}
if (isArray(_subscriptions)) {
index = -1;
len = _subscriptions.length;
while (++index < len) {
const sub = _subscriptions[index];
if (isObject(sub)) {
try {
sub.unsubscribe();
}
catch (e) {
hasErrors = true;
errors = errors || [];
if (e instanceof UnsubscriptionError) {
errors = errors.concat(flattenUnsubscriptionErrors(e.errors));
}
else {
errors.push(e);
}
}
}
}
}
if (hasErrors) {
throw new UnsubscriptionError(errors);
}
}
add(teardown) {
let subscription = teardown;
switch (typeof teardown) {
case 'function':
subscription = new Subscription(teardown);
case 'object':
if (subscription === this || subscription.closed || typeof subscription.unsubscribe !== 'function') {
return subscription;
}
else if (this.closed) {
subscription.unsubscribe();
return subscription;
}
else if (!(subscription instanceof Subscription)) {
const tmp = subscription;
subscription = new Subscription();
subscription._subscriptions = [tmp];
}
break;
default: {
if (!teardown) {
return Subscription.EMPTY;
}
throw new Error('unrecognized teardown ' + teardown + ' added to Subscription.');
}
}
if (subscription._addParent(this)) {
const subscriptions = this._subscriptions;
if (subscriptions) {
subscriptions.push(subscription);
}
else {
this._subscriptions = [subscription];
}
}
return subscription;
}
remove(subscription) {
const subscriptions = this._subscriptions;
if (subscriptions) {
const subscriptionIndex = subscriptions.indexOf(subscription);
if (subscriptionIndex !== -1) {
subscriptions.splice(subscriptionIndex, 1);
}
}
}
_addParent(parent) {
let { _parent, _parents } = this;
if (_parent === parent) {
return false;
}
else if (!_parent) {
this._parent = parent;
return true;
}
else if (!_parents) {
this._parents = [parent];
return true;
}
else if (_parents.indexOf(parent) === -1) {
_parents.push(parent);
return true;
}
return false;
}
}
Subscription.EMPTY = (function (empty) {
empty.closed = true;
return empty;
}(new Subscription()));
function flattenUnsubscriptionErrors(errors) {
return errors.reduce((errs, err) => errs.concat((err instanceof UnsubscriptionError) ? err.errors : err), []);
}
//# sourceMappingURL=Subscription.js.map