AbstractEqualityComparison.js
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'use strict';
var StrictEqualityComparison = require('./StrictEqualityComparison');
var StringToBigInt = require('./StringToBigInt');
var ToNumber = require('./ToNumber');
var ToPrimitive = require('./ToPrimitive');
var Type = require('./Type');
var isNaN = require('../helpers/isNaN');
// https://ecma-international.org/ecma-262/11.0/#sec-abstract-equality-comparison
module.exports = function AbstractEqualityComparison(x, y) {
var xType = Type(x);
var yType = Type(y);
if (xType === yType) {
return StrictEqualityComparison(x, y);
}
if (x == null && y == null) {
return true;
}
if (xType === 'Number' && yType === 'String') {
return AbstractEqualityComparison(x, ToNumber(y));
}
if (xType === 'String' && yType === 'Number') {
return AbstractEqualityComparison(ToNumber(x), y);
}
if (xType === 'BigInt' && yType === 'String') {
var n = StringToBigInt(y);
if (isNaN(n)) {
return false;
}
return AbstractEqualityComparison(x, n);
}
if (xType === 'String' && yType === 'BigInt') {
return AbstractEqualityComparison(y, x);
}
if (xType === 'Boolean') {
return AbstractEqualityComparison(ToNumber(x), y);
}
if (yType === 'Boolean') {
return AbstractEqualityComparison(x, ToNumber(y));
}
if ((xType === 'String' || xType === 'Number' || xType === 'BigInt' || xType === 'Symbol') && yType === 'Object') {
return AbstractEqualityComparison(x, ToPrimitive(y));
}
if (xType === 'Object' && (yType === 'String' || yType === 'Number' || yType === 'BigInt' || yType === 'Symbol')) {
return AbstractEqualityComparison(ToPrimitive(x), y);
}
if ((xType === 'BigInt' && yType === 'Number') || (xType === 'Number' && yType === 'BigInt')) {
if (isNaN(x) || isNaN(y) || x === Infinity || y === Infinity || x === -Infinity || y === -Infinity) {
return false;
}
return x == y; // eslint-disable-line eqeqeq
}
return false;
};