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/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this file,
export function AsyncRunner(callbacks) {
this._callbacks = callbacks;
this._iteratorQueue = [];
// This catches errors reported to the console, e.g., via Cu.reportError.
Services.console.registerListener(this);
}
AsyncRunner.prototype = {
appendIterator: function AR_appendIterator(iter) {
this._iteratorQueue.push(iter);
},
next: function AR_next(arg) {
if (!this._iteratorQueue.length) {
this.destroy();
this._callbacks.done();
return;
}
try {
var { done, value } = this._iteratorQueue[0].next(arg);
if (done) {
this._iteratorQueue.shift();
this.next();
return;
}
} catch (err) {
this._callbacks.error(err);
}
// val is truthy => call next
// val is an iterator => prepend it to the queue and start on it
if (value) {
if (typeof value != "boolean") {
this._iteratorQueue.unshift(value);
}
this.next();
}
},
destroy: function AR_destroy() {
Services.console.unregisterListener(this);
this.destroy = function AR_alreadyDestroyed() {};
},
observe: function AR_consoleServiceListener(msg) {
if (
msg instanceof Ci.nsIScriptError &&
!(msg.flags & Ci.nsIScriptError.warningFlag)
) {
this._callbacks.consoleError(msg);
}
},
};