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diff --git a/src/node_modules/es-abstract/2019/IsPromise.js b/src/node_modules/es-abstract/2019/IsPromise.js
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+'use strict';
+
+var callBound = require('../helpers/callBound');
+
+var $PromiseThen = callBound('Promise.prototype.then', true);
+
+var Type = require('./Type');
+
+// https://www.ecma-international.org/ecma-262/6.0/#sec-ispromise
+
+module.exports = function IsPromise(x) {
+ if (Type(x) !== 'Object') {
+ return false;
+ }
+ if (!$PromiseThen) { // Promises are not supported
+ return false;
+ }
+ try {
+ $PromiseThen(x); // throws if not a promise
+ } catch (e) {
+ return false;
+ }
+ return true;
+};