import isFunction from './isFunction.js'; import isMasked from './_isMasked.js'; import isObject from './isObject.js'; import toSource from './_toSource.js'; /** * Used to match `RegExp` * [syntax characters](http://ecma-international.org/ecma-262/7.0/#sec-patterns). */ const reRegExpChar = /[\\^$.*+?()[\]{}|]/g; /** Used to detect host constructors (Safari). */ const reIsHostCtor = /^\[object .+?Constructor\]$/; /** Used for built-in method references. */ const funcProto = Function.prototype; const objectProto = Object.prototype; /** Used to resolve the decompiled source of functions. */ const funcToString = funcProto.toString; /** Used to check objects for own properties. */ const hasOwnProperty = objectProto.hasOwnProperty; /** Used to detect if a method is native. */ const reIsNative = RegExp(`^${ funcToString.call(hasOwnProperty) .replace(reRegExpChar, '\\$&') .replace(/hasOwnProperty|(function).*?(?=\\\()| for .+?(?=\\\])/g, '$1.*?') }$`); /** * The base implementation of `_.isNative` without bad shim checks. * * @private * @param {*} value The value to check. * @returns {boolean} Returns `true` if `value` is a native function, * else `false`. */ function baseIsNative(value) { if (!isObject(value) || isMasked(value)) { return false; } const pattern = isFunction(value) ? reIsNative : reIsHostCtor; return pattern.test(toSource(value)); } export default baseIsNative;