You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
46 lines
1.1 KiB
46 lines
1.1 KiB
'use strict'; |
|
|
|
var $WeakMap = typeof WeakMap === 'function' && WeakMap.prototype ? WeakMap : null; |
|
var $WeakSet = typeof WeakSet === 'function' && WeakSet.prototype ? WeakSet : null; |
|
|
|
var exported; |
|
|
|
if (!$WeakMap) { |
|
/** @type {import('.')} */ |
|
// eslint-disable-next-line no-unused-vars |
|
exported = function isWeakMap(x) { |
|
// `WeakMap` is not present in this environment. |
|
return false; |
|
}; |
|
} |
|
|
|
var $mapHas = $WeakMap ? $WeakMap.prototype.has : null; |
|
var $setHas = $WeakSet ? $WeakSet.prototype.has : null; |
|
if (!exported && !$mapHas) { |
|
/** @type {import('.')} */ |
|
// eslint-disable-next-line no-unused-vars |
|
exported = function isWeakMap(x) { |
|
// `WeakMap` does not have a `has` method |
|
return false; |
|
}; |
|
} |
|
|
|
/** @type {import('.')} */ |
|
module.exports = exported || function isWeakMap(x) { |
|
if (!x || typeof x !== 'object') { |
|
return false; |
|
} |
|
try { |
|
$mapHas.call(x, $mapHas); |
|
if ($setHas) { |
|
try { |
|
$setHas.call(x, $setHas); |
|
} catch (e) { |
|
return true; |
|
} |
|
} |
|
// @ts-expect-error TS can't figure out that $WeakMap is always truthy here |
|
return x instanceof $WeakMap; // core-js workaround, pre-v3 |
|
} catch (e) {} |
|
return false; |
|
};
|
|
|