import * as util from 'util'; const toString = Object.prototype.toString; const getObjectType = (value: any) => toString.call(value).slice(8, -1) as string; const isOfType = (type: string) => (value: any) => typeof value === type; // tslint:disable-line const isObjectOfType = (type: string) => (value: any) => getObjectType(value) === type; function is(value: any) { // tslint:disable-line:only-arrow-functions if (value === null) { return 'null'; } if (value === true || value === false) { return 'boolean'; } const type = typeof value; if (type === 'undefined') { return 'undefined'; } if (type === 'string') { return 'string'; } if (type === 'number') { return 'number'; } if (type === 'symbol') { return 'symbol'; } if (is.function_(value)) { return 'Function'; } if (Array.isArray(value)) { return 'Array'; } if (Buffer.isBuffer(value)) { return 'Buffer'; } const tagType = getObjectType(value); if (tagType) { return tagType; } if (value instanceof String || value instanceof Boolean || value instanceof Number) { throw new TypeError('Please don\'t use object wrappers for primitive types'); } return 'Object'; } namespace is { // tslint:disable-line:no-namespace const isObject = (value: any) => typeof value === 'object'; // tslint:disable:variable-name export const undefined = isOfType('undefined'); export const string = isOfType('string'); export const number = isOfType('number'); export const function_ = isOfType('function'); export const null_ = (value: any) => value === null; export const class_ = (value: any) => function_(value) && value.toString().startsWith('class '); export const boolean = (value: any) => value === true || value === false; // tslint:enable:variable-name export const symbol = isOfType('symbol'); export const array = Array.isArray; export const buffer = Buffer.isBuffer; export const nullOrUndefined = (value: any) => null_(value) || undefined(value); export const object = (value: any) => !nullOrUndefined(value) && (function_(value) || isObject(value)); export const iterable = (value: any) => !nullOrUndefined(value) && function_(value[Symbol.iterator]); export const generator = (value: any) => iterable(value) && function_(value.next) && function_(value.throw); export const nativePromise = isObjectOfType('Promise'); const hasPromiseAPI = (value: any) => !null_(value) && isObject(value) && function_(value.then) && function_(value.catch); export const promise = (value: any) => nativePromise(value) || hasPromiseAPI(value); // TODO: Change to use `isObjectOfType` once Node.js 6 or higher is targeted const isFunctionOfType = (type: string) => (value: any) => function_(value) && function_(value.constructor) && value.constructor.name === type; export const generatorFunction = isFunctionOfType('GeneratorFunction'); export const asyncFunction = isFunctionOfType('AsyncFunction'); export const regExp = isObjectOfType('RegExp'); export const date = isObjectOfType('Date'); export const error = isObjectOfType('Error'); export const map = isObjectOfType('Map'); export const set = isObjectOfType('Set'); export const weakMap = isObjectOfType('WeakMap'); export const weakSet = isObjectOfType('WeakSet'); export const int8Array = isObjectOfType('Int8Array'); export const uint8Array = isObjectOfType('Uint8Array'); export const uint8ClampedArray = isObjectOfType('Uint8ClampedArray'); export const int16Array = isObjectOfType('Int16Array'); export const uint16Array = isObjectOfType('Uint16Array'); export const int32Array = isObjectOfType('Int32Array'); export const uint32Array = isObjectOfType('Uint32Array'); export const float32Array = isObjectOfType('Float32Array'); export const float64Array = isObjectOfType('Float64Array'); export const arrayBuffer = isObjectOfType('ArrayBuffer'); export const sharedArrayBuffer = isObjectOfType('SharedArrayBuffer'); export const truthy = (value: any) => Boolean(value); export const falsy = (value: any) => !value; export const nan = (value: any) => Number.isNaN(value); const primitiveTypes = new Set([ 'undefined', 'string', 'number', 'boolean', 'symbol' ]); export const primitive = (value: any) => null_(value) || primitiveTypes.has(typeof value); export const integer = (value: any) => Number.isInteger(value); export const safeInteger = (value: any) => Number.isSafeInteger(value); export const plainObject = (value: any) => { // From: https://github.com/sindresorhus/is-plain-obj/blob/master/index.js let prototype; return getObjectType(value) === 'Object' && (prototype = Object.getPrototypeOf(value), prototype === null || // tslint:disable-line:ban-comma-operator prototype === Object.getPrototypeOf({})); }; const typedArrayTypes = new Set([ 'Int8Array', 'Uint8Array', 'Uint8ClampedArray', 'Int16Array', 'Uint16Array', 'Int32Array', 'Uint32Array', 'Float32Array', 'Float64Array' ]); export const typedArray = (value: any) => typedArrayTypes.has(getObjectType(value)); const isValidLength = (value: any) => safeInteger(value) && value > -1; export const arrayLike = (value: any) => !nullOrUndefined(value) && !function_(value) && isValidLength(value.length); export const inRange = (value: number, range: number | number[]) => { if (number(range)) { return value >= Math.min(0, range as number) && value <= Math.max(range as number, 0); } if (array(range) && range.length === 2) { // TODO: Use spread operator here when targeting Node.js 6 or higher return value >= Math.min.apply(null, range) && value <= Math.max.apply(null, range); } throw new TypeError(`Invalid range: ${util.inspect(range)}`); }; const NODE_TYPE_ELEMENT = 1; const DOM_PROPERTIES_TO_CHECK = [ 'innerHTML', 'ownerDocument', 'style', 'attributes', 'nodeValue' ]; export const domElement = (value: any) => object(value) && value.nodeType === NODE_TYPE_ELEMENT && string(value.nodeName) && !plainObject(value) && DOM_PROPERTIES_TO_CHECK.every(property => property in value); export const infinite = (value: any) => value === Infinity || value === -Infinity; const isAbsoluteMod2 = (value: number) => (rem: number) => integer(rem) && Math.abs(rem % 2) === value; export const even = isAbsoluteMod2(0); export const odd = isAbsoluteMod2(1); const isWhiteSpaceString = (value: any) => string(value) && /\S/.test(value) === false; const isEmptyStringOrArray = (value: any) => (string(value) || array(value)) && value.length === 0; const isEmptyObject = (value: any) => !map(value) && !set(value) && object(value) && Object.keys(value).length === 0; const isEmptyMapOrSet = (value: any) => (map(value) || set(value)) && value.size === 0; export const empty = (value: any) => falsy(value) || isEmptyStringOrArray(value) || isEmptyObject(value) || isEmptyMapOrSet(value); export const emptyOrWhitespace = (value: any) => empty(value) || isWhiteSpaceString(value); type ArrayMethod = (fn: (value: any, index: number, arr: any[]) => boolean, thisArg?: any) => boolean; const predicateOnArray = (method: ArrayMethod, predicate: any, args: IArguments) => { // `args` is the calling function's "arguments object". // We have to do it this way to keep node v4 support. // So here we convert it to an array and slice off the first item. const values = Array.prototype.slice.call(args, 1); if (function_(predicate) === false) { throw new TypeError(`Invalid predicate: ${util.inspect(predicate)}`); } if (values.length === 0) { throw new TypeError('Invalid number of values'); } return method.call(values, predicate); }; // We can't use rest parameters in node v4 due to the lack of the spread operator. // Therefore We have to use anonymous functions for the any() and all() methods // tslint:disable:only-arrow-functions no-function-expression export function any(...predicate: any[]): any; // tslint:disable-line:variable-name export function any(predicate: any) { return predicateOnArray(Array.prototype.some, predicate, arguments); } export function all(...predicate: any[]): any; export function all(predicate: any) { return predicateOnArray(Array.prototype.every, predicate, arguments); } // tslint:enable:only-arrow-functions no-function-expression } // Some few keywords are reserved, but we'll populate them for the node-folks // See https://github.com/Microsoft/TypeScript/issues/2536 Object.defineProperties(is, { class: {value: is.class_}, function: {value: is.function_}, null: {value: is.null_} }); export default is; // tslint:disable-line:no-default-export