wallet-core/node_modules/promise/setimmediate/core.js

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'use strict';
function noop() {}
// States:
//
// 0 - pending
// 1 - fulfilled with _value
// 2 - rejected with _value
// 3 - adopted the state of another promise, _value
//
// once the state is no longer pending (0) it is immutable
// All `_` prefixed properties will be reduced to `_{random number}`
// at build time to obfuscate them and discourage their use.
// We don't use symbols or Object.defineProperty to fully hide them
// because the performance isn't good enough.
// to avoid using try/catch inside critical functions, we
// extract them to here.
var LAST_ERROR = null;
var IS_ERROR = {};
function getThen(obj) {
try {
return obj.then;
} catch (ex) {
LAST_ERROR = ex;
return IS_ERROR;
}
}
function tryCallOne(fn, a) {
try {
return fn(a);
} catch (ex) {
LAST_ERROR = ex;
return IS_ERROR;
}
}
function tryCallTwo(fn, a, b) {
try {
fn(a, b);
} catch (ex) {
LAST_ERROR = ex;
return IS_ERROR;
}
}
module.exports = Promise;
function Promise(fn) {
if (typeof this !== 'object') {
throw new TypeError('Promises must be constructed via new');
}
if (typeof fn !== 'function') {
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throw new TypeError('Promise constructor\'s argument is not a function');
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}
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this._75 = 0;
this._83 = 0;
this._18 = null;
this._38 = null;
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if (fn === noop) return;
doResolve(fn, this);
}
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Promise._47 = null;
Promise._71 = null;
Promise._44 = noop;
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Promise.prototype.then = function(onFulfilled, onRejected) {
if (this.constructor !== Promise) {
return safeThen(this, onFulfilled, onRejected);
}
var res = new Promise(noop);
handle(this, new Handler(onFulfilled, onRejected, res));
return res;
};
function safeThen(self, onFulfilled, onRejected) {
return new self.constructor(function (resolve, reject) {
var res = new Promise(noop);
res.then(resolve, reject);
handle(self, new Handler(onFulfilled, onRejected, res));
});
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}
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function handle(self, deferred) {
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while (self._83 === 3) {
self = self._18;
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}
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if (Promise._47) {
Promise._47(self);
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}
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if (self._83 === 0) {
if (self._75 === 0) {
self._75 = 1;
self._38 = deferred;
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return;
}
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if (self._75 === 1) {
self._75 = 2;
self._38 = [self._38, deferred];
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return;
}
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self._38.push(deferred);
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return;
}
handleResolved(self, deferred);
}
function handleResolved(self, deferred) {
setImmediate(function() {
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var cb = self._83 === 1 ? deferred.onFulfilled : deferred.onRejected;
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if (cb === null) {
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if (self._83 === 1) {
resolve(deferred.promise, self._18);
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} else {
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reject(deferred.promise, self._18);
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}
return;
}
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var ret = tryCallOne(cb, self._18);
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if (ret === IS_ERROR) {
reject(deferred.promise, LAST_ERROR);
} else {
resolve(deferred.promise, ret);
}
});
}
function resolve(self, newValue) {
// Promise Resolution Procedure: https://github.com/promises-aplus/promises-spec#the-promise-resolution-procedure
if (newValue === self) {
return reject(
self,
new TypeError('A promise cannot be resolved with itself.')
);
}
if (
newValue &&
(typeof newValue === 'object' || typeof newValue === 'function')
) {
var then = getThen(newValue);
if (then === IS_ERROR) {
return reject(self, LAST_ERROR);
}
if (
then === self.then &&
newValue instanceof Promise
) {
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self._83 = 3;
self._18 = newValue;
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finale(self);
return;
} else if (typeof then === 'function') {
doResolve(then.bind(newValue), self);
return;
}
}
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self._83 = 1;
self._18 = newValue;
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finale(self);
}
function reject(self, newValue) {
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self._83 = 2;
self._18 = newValue;
if (Promise._71) {
Promise._71(self, newValue);
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}
finale(self);
}
function finale(self) {
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if (self._75 === 1) {
handle(self, self._38);
self._38 = null;
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}
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if (self._75 === 2) {
for (var i = 0; i < self._38.length; i++) {
handle(self, self._38[i]);
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}
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self._38 = null;
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}
}
function Handler(onFulfilled, onRejected, promise){
this.onFulfilled = typeof onFulfilled === 'function' ? onFulfilled : null;
this.onRejected = typeof onRejected === 'function' ? onRejected : null;
this.promise = promise;
}
/**
* Take a potentially misbehaving resolver function and make sure
* onFulfilled and onRejected are only called once.
*
* Makes no guarantees about asynchrony.
*/
function doResolve(fn, promise) {
var done = false;
var res = tryCallTwo(fn, function (value) {
if (done) return;
done = true;
resolve(promise, value);
}, function (reason) {
if (done) return;
done = true;
reject(promise, reason);
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});
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if (!done && res === IS_ERROR) {
done = true;
reject(promise, LAST_ERROR);
}
}