GetIntrinsic.js 11.3 KB
'use strict';

/* globals
	AggregateError,
	Atomics,
	FinalizationRegistry,
	SharedArrayBuffer,
	WeakRef,
*/

var undefined;

var $SyntaxError = SyntaxError;
var $Function = Function;
var $TypeError = TypeError;

// eslint-disable-next-line consistent-return
var getEvalledConstructor = function (expressionSyntax) {
	try {
		// eslint-disable-next-line no-new-func
		return Function('"use strict"; return (' + expressionSyntax + ').constructor;')();
	} catch (e) {}
};

var $gOPD = Object.getOwnPropertyDescriptor;
if ($gOPD) {
	try {
		$gOPD({}, '');
	} catch (e) {
		$gOPD = null; // this is IE 8, which has a broken gOPD
	}
}

var throwTypeError = function () { throw new $TypeError(); };
var ThrowTypeError = $gOPD
	? (function () {
		try {
			// eslint-disable-next-line no-unused-expressions, no-caller, no-restricted-properties
			arguments.callee; // IE 8 does not throw here
			return throwTypeError;
		} catch (calleeThrows) {
			try {
				// IE 8 throws on Object.getOwnPropertyDescriptor(arguments, '')
				return $gOPD(arguments, 'callee').get;
			} catch (gOPDthrows) {
				return throwTypeError;
			}
		}
	}())
	: throwTypeError;

var hasSymbols = require('has-symbols')();

var getProto = Object.getPrototypeOf || function (x) { return x.__proto__; }; // eslint-disable-line no-proto

var asyncGenFunction = getEvalledConstructor('async function* () {}');
var asyncGenFunctionPrototype = asyncGenFunction ? asyncGenFunction.prototype : undefined;
var asyncGenPrototype = asyncGenFunctionPrototype ? asyncGenFunctionPrototype.prototype : undefined;

var TypedArray = typeof Uint8Array === 'undefined' ? undefined : getProto(Uint8Array);

var INTRINSICS = {
	'%AggregateError%': typeof AggregateError === 'undefined' ? undefined : AggregateError,
	'%Array%': Array,
	'%ArrayBuffer%': typeof ArrayBuffer === 'undefined' ? undefined : ArrayBuffer,
	'%ArrayIteratorPrototype%': hasSymbols ? getProto([][Symbol.iterator]()) : undefined,
	'%AsyncFromSyncIteratorPrototype%': undefined,
	'%AsyncFunction%': getEvalledConstructor('async function () {}'),
	'%AsyncGenerator%': asyncGenFunctionPrototype,
	'%AsyncGeneratorFunction%': asyncGenFunction,
	'%AsyncIteratorPrototype%': asyncGenPrototype ? getProto(asyncGenPrototype) : undefined,
	'%Atomics%': typeof Atomics === 'undefined' ? undefined : Atomics,
	'%BigInt%': typeof BigInt === 'undefined' ? undefined : BigInt,
	'%Boolean%': Boolean,
	'%DataView%': typeof DataView === 'undefined' ? undefined : DataView,
	'%Date%': Date,
	'%decodeURI%': decodeURI,
	'%decodeURIComponent%': decodeURIComponent,
	'%encodeURI%': encodeURI,
	'%encodeURIComponent%': encodeURIComponent,
	'%Error%': Error,
	'%eval%': eval, // eslint-disable-line no-eval
	'%EvalError%': EvalError,
	'%Float32Array%': typeof Float32Array === 'undefined' ? undefined : Float32Array,
	'%Float64Array%': typeof Float64Array === 'undefined' ? undefined : Float64Array,
	'%FinalizationRegistry%': typeof FinalizationRegistry === 'undefined' ? undefined : FinalizationRegistry,
	'%Function%': $Function,
	'%GeneratorFunction%': getEvalledConstructor('function* () {}'),
	'%Int8Array%': typeof Int8Array === 'undefined' ? undefined : Int8Array,
	'%Int16Array%': typeof Int16Array === 'undefined' ? undefined : Int16Array,
	'%Int32Array%': typeof Int32Array === 'undefined' ? undefined : Int32Array,
	'%isFinite%': isFinite,
	'%isNaN%': isNaN,
	'%IteratorPrototype%': hasSymbols ? getProto(getProto([][Symbol.iterator]())) : undefined,
	'%JSON%': typeof JSON === 'object' ? JSON : undefined,
	'%Map%': typeof Map === 'undefined' ? undefined : Map,
	'%MapIteratorPrototype%': typeof Map === 'undefined' || !hasSymbols ? undefined : getProto(new Map()[Symbol.iterator]()),
	'%Math%': Math,
	'%Number%': Number,
	'%Object%': Object,
	'%parseFloat%': parseFloat,
	'%parseInt%': parseInt,
	'%Promise%': typeof Promise === 'undefined' ? undefined : Promise,
	'%Proxy%': typeof Proxy === 'undefined' ? undefined : Proxy,
	'%RangeError%': RangeError,
	'%ReferenceError%': ReferenceError,
	'%Reflect%': typeof Reflect === 'undefined' ? undefined : Reflect,
	'%RegExp%': RegExp,
	'%Set%': typeof Set === 'undefined' ? undefined : Set,
	'%SetIteratorPrototype%': typeof Set === 'undefined' || !hasSymbols ? undefined : getProto(new Set()[Symbol.iterator]()),
	'%SharedArrayBuffer%': typeof SharedArrayBuffer === 'undefined' ? undefined : SharedArrayBuffer,
	'%String%': String,
	'%StringIteratorPrototype%': hasSymbols ? getProto(''[Symbol.iterator]()) : undefined,
	'%Symbol%': hasSymbols ? Symbol : undefined,
	'%SyntaxError%': $SyntaxError,
	'%ThrowTypeError%': ThrowTypeError,
	'%TypedArray%': TypedArray,
	'%TypeError%': $TypeError,
	'%Uint8Array%': typeof Uint8Array === 'undefined' ? undefined : Uint8Array,
	'%Uint8ClampedArray%': typeof Uint8ClampedArray === 'undefined' ? undefined : Uint8ClampedArray,
	'%Uint16Array%': typeof Uint16Array === 'undefined' ? undefined : Uint16Array,
	'%Uint32Array%': typeof Uint32Array === 'undefined' ? undefined : Uint32Array,
	'%URIError%': URIError,
	'%WeakMap%': typeof WeakMap === 'undefined' ? undefined : WeakMap,
	'%WeakRef%': typeof WeakRef === 'undefined' ? undefined : WeakRef,
	'%WeakSet%': typeof WeakSet === 'undefined' ? undefined : WeakSet
};

var LEGACY_ALIASES = {
	'%ArrayBufferPrototype%': ['ArrayBuffer', 'prototype'],
	'%ArrayPrototype%': ['Array', 'prototype'],
	'%ArrayProto_entries%': ['Array', 'prototype', 'entries'],
	'%ArrayProto_forEach%': ['Array', 'prototype', 'forEach'],
	'%ArrayProto_keys%': ['Array', 'prototype', 'keys'],
	'%ArrayProto_values%': ['Array', 'prototype', 'values'],
	'%AsyncFunctionPrototype%': ['AsyncFunction', 'prototype'],
	'%AsyncGenerator%': ['AsyncGeneratorFunction', 'prototype'],
	'%AsyncGeneratorPrototype%': ['AsyncGeneratorFunction', 'prototype', 'prototype'],
	'%BooleanPrototype%': ['Boolean', 'prototype'],
	'%DataViewPrototype%': ['DataView', 'prototype'],
	'%DatePrototype%': ['Date', 'prototype'],
	'%ErrorPrototype%': ['Error', 'prototype'],
	'%EvalErrorPrototype%': ['EvalError', 'prototype'],
	'%Float32ArrayPrototype%': ['Float32Array', 'prototype'],
	'%Float64ArrayPrototype%': ['Float64Array', 'prototype'],
	'%FunctionPrototype%': ['Function', 'prototype'],
	'%Generator%': ['GeneratorFunction', 'prototype'],
	'%GeneratorPrototype%': ['GeneratorFunction', 'prototype', 'prototype'],
	'%Int8ArrayPrototype%': ['Int8Array', 'prototype'],
	'%Int16ArrayPrototype%': ['Int16Array', 'prototype'],
	'%Int32ArrayPrototype%': ['Int32Array', 'prototype'],
	'%JSONParse%': ['JSON', 'parse'],
	'%JSONStringify%': ['JSON', 'stringify'],
	'%MapPrototype%': ['Map', 'prototype'],
	'%NumberPrototype%': ['Number', 'prototype'],
	'%ObjectPrototype%': ['Object', 'prototype'],
	'%ObjProto_toString%': ['Object', 'prototype', 'toString'],
	'%ObjProto_valueOf%': ['Object', 'prototype', 'valueOf'],
	'%PromisePrototype%': ['Promise', 'prototype'],
	'%PromiseProto_then%': ['Promise', 'prototype', 'then'],
	'%Promise_all%': ['Promise', 'all'],
	'%Promise_reject%': ['Promise', 'reject'],
	'%Promise_resolve%': ['Promise', 'resolve'],
	'%RangeErrorPrototype%': ['RangeError', 'prototype'],
	'%ReferenceErrorPrototype%': ['ReferenceError', 'prototype'],
	'%RegExpPrototype%': ['RegExp', 'prototype'],
	'%SetPrototype%': ['Set', 'prototype'],
	'%SharedArrayBufferPrototype%': ['SharedArrayBuffer', 'prototype'],
	'%StringPrototype%': ['String', 'prototype'],
	'%SymbolPrototype%': ['Symbol', 'prototype'],
	'%SyntaxErrorPrototype%': ['SyntaxError', 'prototype'],
	'%TypedArrayPrototype%': ['TypedArray', 'prototype'],
	'%TypeErrorPrototype%': ['TypeError', 'prototype'],
	'%Uint8ArrayPrototype%': ['Uint8Array', 'prototype'],
	'%Uint8ClampedArrayPrototype%': ['Uint8ClampedArray', 'prototype'],
	'%Uint16ArrayPrototype%': ['Uint16Array', 'prototype'],
	'%Uint32ArrayPrototype%': ['Uint32Array', 'prototype'],
	'%URIErrorPrototype%': ['URIError', 'prototype'],
	'%WeakMapPrototype%': ['WeakMap', 'prototype'],
	'%WeakSetPrototype%': ['WeakSet', 'prototype']
};

var bind = require('function-bind');
var hasOwn = require('has');
var $concat = bind.call(Function.call, Array.prototype.concat);
var $spliceApply = bind.call(Function.apply, Array.prototype.splice);
var $replace = bind.call(Function.call, String.prototype.replace);

/* adapted from https://github.com/lodash/lodash/blob/4.17.15/dist/lodash.js#L6735-L6744 */
var rePropName = /[^%.[\]]+|\[(?:(-?\d+(?:\.\d+)?)|(["'])((?:(?!\2)[^\\]|\\.)*?)\2)\]|(?=(?:\.|\[\])(?:\.|\[\]|%$))/g;
var reEscapeChar = /\\(\\)?/g; /** Used to match backslashes in property paths. */
var stringToPath = function stringToPath(string) {
	var result = [];
	$replace(string, rePropName, function (match, number, quote, subString) {
		result[result.length] = quote ? $replace(subString, reEscapeChar, '$1') : number || match;
	});
	return result;
};
/* end adaptation */

var getBaseIntrinsic = function getBaseIntrinsic(name, allowMissing) {
	var intrinsicName = name;
	var alias;
	if (hasOwn(LEGACY_ALIASES, intrinsicName)) {
		alias = LEGACY_ALIASES[intrinsicName];
		intrinsicName = '%' + alias[0] + '%';
	}

	if (hasOwn(INTRINSICS, intrinsicName)) {
		var value = INTRINSICS[intrinsicName];
		if (typeof value === 'undefined' && !allowMissing) {
			throw new $TypeError('intrinsic ' + name + ' exists, but is not available. Please file an issue!');
		}

		return {
			alias: alias,
			name: intrinsicName,
			value: value
		};
	}

	throw new $SyntaxError('intrinsic ' + name + ' does not exist!');
};

module.exports = function GetIntrinsic(name, allowMissing) {
	if (typeof name !== 'string' || name.length === 0) {
		throw new $TypeError('intrinsic name must be a non-empty string');
	}
	if (arguments.length > 1 && typeof allowMissing !== 'boolean') {
		throw new $TypeError('"allowMissing" argument must be a boolean');
	}

	var parts = stringToPath(name);
	var intrinsicBaseName = parts.length > 0 ? parts[0] : '';

	var intrinsic = getBaseIntrinsic('%' + intrinsicBaseName + '%', allowMissing);
	var intrinsicRealName = intrinsic.name;
	var value = intrinsic.value;
	var skipFurtherCaching = false;

	var alias = intrinsic.alias;
	if (alias) {
		intrinsicBaseName = alias[0];
		$spliceApply(parts, $concat([0, 1], alias));
	}

	for (var i = 1, isOwn = true; i < parts.length; i += 1) {
		var part = parts[i];
		if (part === 'constructor' || !isOwn) {
			skipFurtherCaching = true;
		}

		intrinsicBaseName += '.' + part;
		intrinsicRealName = '%' + intrinsicBaseName + '%';

		if (hasOwn(INTRINSICS, intrinsicRealName)) {
			value = INTRINSICS[intrinsicRealName];
		} else if (value != null) {
			if ($gOPD && (i + 1) >= parts.length) {
				var desc = $gOPD(value, part);
				isOwn = !!desc;

				if (!allowMissing && !(part in value)) {
					throw new $TypeError('base intrinsic for ' + name + ' exists, but the property is not available.');
				}
				// By convention, when a data property is converted to an accessor
				// property to emulate a data property that does not suffer from
				// the override mistake, that accessor's getter is marked with
				// an `originalValue` property. Here, when we detect this, we
				// uphold the illusion by pretending to see that original data
				// property, i.e., returning the value rather than the getter
				// itself.
				if (isOwn && 'get' in desc && !('originalValue' in desc.get)) {
					value = desc.get;
				} else {
					value = value[part];
				}
			} else {
				isOwn = hasOwn(value, part);
				value = value[part];
			}

			if (isOwn && !skipFurtherCaching) {
				INTRINSICS[intrinsicRealName] = value;
			}
		}
	}
	return value;
};