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"use strict";
module.exports = function(Promise, tryConvertToPromise) {
var util = require("./util");
var CancellationError = Promise.CancellationError;
var errorObj = util.errorObj;
function PassThroughHandlerContext(promise, type, handler) {
this.promise = promise;
this.type = type;
this.handler = handler;
this.called = false;
this.cancelPromise = null;
}
PassThroughHandlerContext.prototype.isFinallyHandler = function() {
return this.type === 0;
};
function FinallyHandlerCancelReaction(finallyHandler) {
this.finallyHandler = finallyHandler;
}
FinallyHandlerCancelReaction.prototype._resultCancelled = function() {
checkCancel(this.finallyHandler);
};
function checkCancel(ctx, reason) {
if (ctx.cancelPromise != null) {
if (arguments.length > 1) {
ctx.cancelPromise._reject(reason);
} else {
ctx.cancelPromise._cancel();
}
ctx.cancelPromise = null;
return true;
}
return false;
}
function succeed() {
return finallyHandler.call(this, this.promise._target()._settledValue());
}
function fail(reason) {
if (checkCancel(this, reason)) return;
errorObj.e = reason;
return errorObj;
}
function finallyHandler(reasonOrValue) {
var promise = this.promise;
var handler = this.handler;
if (!this.called) {
this.called = true;
var ret = this.isFinallyHandler()
? handler.call(promise._boundValue())
: handler.call(promise._boundValue(), reasonOrValue);
if (ret !== undefined) {
promise._setReturnedNonUndefined();
var maybePromise = tryConvertToPromise(ret, promise);
if (maybePromise instanceof Promise) {
if (this.cancelPromise != null) {
if (maybePromise._isCancelled()) {
var reason =
new CancellationError("late cancellation observer");
promise._attachExtraTrace(reason);
errorObj.e = reason;
return errorObj;
} else if (maybePromise.isPending()) {
maybePromise._attachCancellationCallback(
new FinallyHandlerCancelReaction(this));
}
}
return maybePromise._then(
succeed, fail, undefined, this, undefined);
}
}
}
if (promise.isRejected()) {
checkCancel(this);
errorObj.e = reasonOrValue;
return errorObj;
} else {
checkCancel(this);
return reasonOrValue;
}
}
Promise.prototype._passThrough = function(handler, type, success, fail) {
if (typeof handler !== "function") return this.then();
return this._then(success,
fail,
undefined,
new PassThroughHandlerContext(this, type, handler),
undefined);
};
Promise.prototype.lastly =
Promise.prototype["finally"] = function (handler) {
return this._passThrough(handler,
0,
finallyHandler,
finallyHandler);
};
Promise.prototype.tap = function (handler) {
return this._passThrough(handler, 1, finallyHandler);
};
return PassThroughHandlerContext;
};
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