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1'use strict';2 3/** @type {(t: import('tape').Test) => false | void} */4// eslint-disable-next-line consistent-return5module.exports = function runSymbolTests(t) {6	t.equal(typeof Symbol, 'function', 'global Symbol is a function');7 8	if (typeof Symbol !== 'function') { return false; }9 10	t.notEqual(Symbol(), Symbol(), 'two symbols are not equal');11 12	/*13	t.equal(14		Symbol.prototype.toString.call(Symbol('foo')),15		Symbol.prototype.toString.call(Symbol('foo')),16		'two symbols with the same description stringify the same'17	);18	*/19 20	/*21	var foo = Symbol('foo');22 23	t.notEqual(24		String(foo),25		String(Symbol('bar')),26		'two symbols with different descriptions do not stringify the same'27	);28	*/29 30	t.equal(typeof Symbol.prototype.toString, 'function', 'Symbol#toString is a function');31	// t.equal(String(foo), Symbol.prototype.toString.call(foo), 'Symbol#toString equals String of the same symbol');32 33	t.equal(typeof Object.getOwnPropertySymbols, 'function', 'Object.getOwnPropertySymbols is a function');34 35	/** @type {{ [k in symbol]?: unknown }} */36	var obj = {};37	var sym = Symbol('test');38	var symObj = Object(sym);39	t.notEqual(typeof sym, 'string', 'Symbol is not a string');40	t.equal(Object.prototype.toString.call(sym), '[object Symbol]', 'symbol primitive Object#toStrings properly');41	t.equal(Object.prototype.toString.call(symObj), '[object Symbol]', 'symbol primitive Object#toStrings properly');42 43	var symVal = 42;44	obj[sym] = symVal;45	// eslint-disable-next-line no-restricted-syntax, no-unused-vars46	for (var _ in obj) { t.fail('symbol property key was found in for..in of object'); }47 48	t.deepEqual(Object.keys(obj), [], 'no enumerable own keys on symbol-valued object');49	t.deepEqual(Object.getOwnPropertyNames(obj), [], 'no own names on symbol-valued object');50	t.deepEqual(Object.getOwnPropertySymbols(obj), [sym], 'one own symbol on symbol-valued object');51	t.equal(Object.prototype.propertyIsEnumerable.call(obj, sym), true, 'symbol is enumerable');52	t.deepEqual(Object.getOwnPropertyDescriptor(obj, sym), {53		configurable: true,54		enumerable: true,55		value: 42,56		writable: true57	}, 'property descriptor is correct');58};59