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'use strict';
// https://github.com/tc39/proposal-observable
var $ = require('../internals/export');
var call = require('../internals/function-call');
var DESCRIPTORS = require('../internals/descriptors');
var setSpecies = require('../internals/set-species');
var aCallable = require('../internals/a-callable');
var isCallable = require('../internals/is-callable');
var anObject = require('../internals/an-object');
var isObject = require('../internals/is-object');
var anInstance = require('../internals/an-instance');
var getMethod = require('../internals/get-method');
var defineBuiltIn = require('../internals/define-built-in');
var defineBuiltIns = require('../internals/define-built-ins');
var defineBuiltInAccessor = require('../internals/define-built-in-accessor');
var hostReportErrors = require('../internals/host-report-errors');
var wellKnownSymbol = require('../internals/well-known-symbol');
var InternalStateModule = require('../internals/internal-state');
var OBSERVABLE_FORCED = require('../internals/observable-forced');
var $$OBSERVABLE = wellKnownSymbol('observable');
var OBSERVABLE = 'Observable';
var SUBSCRIPTION = 'Subscription';
var SUBSCRIPTION_OBSERVER = 'SubscriptionObserver';
var getterFor = InternalStateModule.getterFor;
var setInternalState = InternalStateModule.set;
var getObservableInternalState = getterFor(OBSERVABLE);
var getSubscriptionInternalState = getterFor(SUBSCRIPTION);
var getSubscriptionObserverInternalState = getterFor(SUBSCRIPTION_OBSERVER);
var SubscriptionState = function (observer) {
this.observer = anObject(observer);
this.cleanup = undefined;
this.subscriptionObserver = undefined;
};
SubscriptionState.prototype = {
type: SUBSCRIPTION,
clean: function () {
var cleanup = this.cleanup;
if (cleanup) {
this.cleanup = undefined;
try {
cleanup();
} catch (error) {
hostReportErrors(error);
}
}
},
close: function () {
if (!DESCRIPTORS) {
var subscription = this.facade;
var subscriptionObserver = this.subscriptionObserver;
subscription.closed = true;
if (subscriptionObserver) subscriptionObserver.closed = true;
} this.observer = undefined;
},
isClosed: function () {
return this.observer === undefined;
}
};
var Subscription = function (observer, subscriber) {
var subscriptionState = setInternalState(this, new SubscriptionState(observer));
var start;
if (!DESCRIPTORS) this.closed = false;
try {
if (start = getMethod(observer, 'start')) call(start, observer, this);
} catch (error) {
hostReportErrors(error);
}
if (subscriptionState.isClosed()) return;
var subscriptionObserver = subscriptionState.subscriptionObserver = new SubscriptionObserver(subscriptionState);
try {
var cleanup = subscriber(subscriptionObserver);
var subscription = cleanup;
if (cleanup != null) subscriptionState.cleanup = isCallable(cleanup.unsubscribe)
? function () { subscription.unsubscribe(); }
: aCallable(cleanup);
} catch (error) {
subscriptionObserver.error(error);
return;
} if (subscriptionState.isClosed()) subscriptionState.clean();
};
Subscription.prototype = defineBuiltIns({}, {
unsubscribe: function unsubscribe() {
var subscriptionState = getSubscriptionInternalState(this);
if (!subscriptionState.isClosed()) {
subscriptionState.close();
subscriptionState.clean();
}
}
});
if (DESCRIPTORS) defineBuiltInAccessor(Subscription.prototype, 'closed', {
configurable: true,
get: function closed() {
return getSubscriptionInternalState(this).isClosed();
}
});
var SubscriptionObserver = function (subscriptionState) {
setInternalState(this, {
type: SUBSCRIPTION_OBSERVER,
subscriptionState: subscriptionState
});
if (!DESCRIPTORS) this.closed = false;
};
SubscriptionObserver.prototype = defineBuiltIns({}, {
next: function next(value) {
var subscriptionState = getSubscriptionObserverInternalState(this).subscriptionState;
if (!subscriptionState.isClosed()) {
var observer = subscriptionState.observer;
try {
var nextMethod = getMethod(observer, 'next');
if (nextMethod) call(nextMethod, observer, value);
} catch (error) {
hostReportErrors(error);
}
}
},
error: function error(value) {
var subscriptionState = getSubscriptionObserverInternalState(this).subscriptionState;
if (!subscriptionState.isClosed()) {
var observer = subscriptionState.observer;
subscriptionState.close();
try {
var errorMethod = getMethod(observer, 'error');
if (errorMethod) call(errorMethod, observer, value);
else hostReportErrors(value);
} catch (err) {
hostReportErrors(err);
} subscriptionState.clean();
}
},
complete: function complete() {
var subscriptionState = getSubscriptionObserverInternalState(this).subscriptionState;
if (!subscriptionState.isClosed()) {
var observer = subscriptionState.observer;
subscriptionState.close();
try {
var completeMethod = getMethod(observer, 'complete');
if (completeMethod) call(completeMethod, observer);
} catch (error) {
hostReportErrors(error);
} subscriptionState.clean();
}
}
});
if (DESCRIPTORS) defineBuiltInAccessor(SubscriptionObserver.prototype, 'closed', {
configurable: true,
get: function closed() {
return getSubscriptionObserverInternalState(this).subscriptionState.isClosed();
}
});
var $Observable = function Observable(subscriber) {
anInstance(this, ObservablePrototype);
setInternalState(this, {
type: OBSERVABLE,
subscriber: aCallable(subscriber)
});
};
var ObservablePrototype = $Observable.prototype;
defineBuiltIns(ObservablePrototype, {
subscribe: function subscribe(observer) {
var length = arguments.length;
return new Subscription(isCallable(observer) ? {
next: observer,
error: length > 1 ? arguments[1] : undefined,
complete: length > 2 ? arguments[2] : undefined
} : isObject(observer) ? observer : {}, getObservableInternalState(this).subscriber);
}
});
defineBuiltIn(ObservablePrototype, $$OBSERVABLE, function () { return this; });
$({ global: true, constructor: true, forced: OBSERVABLE_FORCED }, {
Observable: $Observable
});
setSpecies(OBSERVABLE);