main repo

node_modules/es-abstract/2020/SetFunctionLength.js

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+'use strict';
+
+var $TypeError = require('es-errors/type');
+
+var DefinePropertyOrThrow = require('./DefinePropertyOrThrow');
+var HasOwnProperty = require('./HasOwnProperty');
+var IsExtensible = require('./IsExtensible');
+var IsNonNegativeInteger = require('./IsNonNegativeInteger');
+
+// https://262.ecma-international.org/11.0/#sec-setfunctionlength
+
+module.exports = function SetFunctionLength(F, length) {
+	if (typeof F !== 'function' || !IsExtensible(F) || HasOwnProperty(F, 'length')) {
+		throw new $TypeError('Assertion failed: `F` must be an extensible function and lack an own `length` property');
+	}
+	if (typeof length !== 'number') {
+		throw new $TypeError('Assertion failed: `length` must be a Number');
+	}
+	if (!IsNonNegativeInteger(length)) {
+		throw new $TypeError('Assertion failed: `length` must be an integer >= 0');
+	}
+	return DefinePropertyOrThrow(F, 'length', {
+		'[[Configurable]]': true,
+		'[[Enumerable]]': false,
+		'[[Value]]': length,
+		'[[Writable]]': false
+	});
+};