1 files changed, 37 insertions, 0 deletions
diff --git a/node_modules/es-abstract/2019/AbstractEqualityComparison.js b/node_modules/es-abstract/2019/AbstractEqualityComparison.js
new file mode 100644
index 000000000..40b390986
--- /dev/null
+++ b/node_modules/es-abstract/2019/AbstractEqualityComparison.js
@@ -0,0 +1,37 @@
+'use strict';
+
+var ToNumber = require('./ToNumber');
+var ToPrimitive = require('./ToPrimitive');
+var Type = require('./Type');
+
+// https://www.ecma-international.org/ecma-262/6.0/#sec-abstract-equality-comparison
+
+module.exports = function AbstractEqualityComparison(x, y) {
+	var xType = Type(x);
+	var yType = Type(y);
+	if (xType === yType) {
+		return x === y; // ES6+ specified this shortcut anyways.
+	}
+	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 === 'Boolean') {
+		return AbstractEqualityComparison(ToNumber(x), y);
+	}
+	if (yType === 'Boolean') {
+		return AbstractEqualityComparison(x, ToNumber(y));
+	}
+	if ((xType === 'String' || xType === 'Number' || xType === 'Symbol') && yType === 'Object') {
+		return AbstractEqualityComparison(x, ToPrimitive(y));
+	}
+	if (xType === 'Object' && (yType === 'String' || yType === 'Number' || yType === 'Symbol')) {
+		return AbstractEqualityComparison(ToPrimitive(x), y);
+	}
+	return false;
+};