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JS type check (TypeScript supported) functions like `isPlainObject() isArray()` etc. A simple & small integration.
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export type AnyFunction = (...args: any[]) => any
export type AnyAsyncFunction = (...args: any[]) => Promise
export type AnyClass = new (...args: any[]) => any
export type PlainObject = Record

type TypeGuard = (payload: A) => payload is B

/**
 * Returns the object type of the given payload
 *
 * @param {*} payload
 * @returns {string}
 */
export function getType(payload: any): string {
  return Object.prototype.toString.call(payload).slice(8, -1)
}

/**
 * Returns whether the payload is undefined
 *
 * @param {*} payload
 * @returns {payload is undefined}
 */
export function isUndefined(payload: any): payload is undefined {
  return getType(payload) === 'Undefined'
}

/**
 * Returns whether the payload is null
 *
 * @param {*} payload
 * @returns {payload is null}
 */
export function isNull(payload: any): payload is null {
  return getType(payload) === 'Null'
}

/**
 * Returns whether the payload is a plain JavaScript object (excluding special classes or objects with other prototypes)
 *
 * @param {*} payload
 * @returns {payload is PlainObject}
 */
export function isPlainObject(payload: any): payload is PlainObject {
  if (getType(payload) !== 'Object') return false
  return payload.constructor === Object && Object.getPrototypeOf(payload) === Object.prototype
}

/**
 * Returns whether the payload is a plain JavaScript object (excluding special classes or objects with other prototypes)
 *
 * @param {*} payload
 * @returns {payload is PlainObject}
 */
export function isObject(payload: any): payload is PlainObject {
  return isPlainObject(payload)
}

/**
 * Returns whether the payload is a an empty object (excluding special classes or objects with other prototypes)
 *
 * @param {*} payload
 * @returns {payload is { [K in any]: never }}
 */
export function isEmptyObject(payload: any): payload is { [K in any]: never } {
  return isPlainObject(payload) && Object.keys(payload).length === 0
}

/**
 * Returns whether the payload is a an empty object (excluding special classes or objects with other prototypes)
 *
 * @param {*} payload
 * @returns {payload is PlainObject}
 */
export function isFullObject(payload: any): payload is PlainObject {
  return isPlainObject(payload) && Object.keys(payload).length > 0
}

/**
 * Returns whether the payload is an any kind of object (including special classes or objects with different prototypes)
 *
 * @param {*} payload
 * @returns {payload is PlainObject}
 */
export function isAnyObject(payload: any): payload is PlainObject {
  return getType(payload) === 'Object'
}

/**
 * Returns whether the payload is an object like a type passed in < >
 *
 * Usage: isObjectLike<{id: any}>(payload) // will make sure it's an object and has an `id` prop.
 *
 * @template T this must be passed in < >
 * @param {*} payload
 * @returns {payload is T}
 */
export function isObjectLike(payload: any): payload is T {
  return isAnyObject(payload)
}

/**
 * Returns whether the payload is a function (regular or async)
 *
 * @param {*} payload
 * @returns {payload is AnyFunction}
 */
export function isFunction(payload: any): payload is AnyFunction {
  return typeof payload === 'function'
}

/**
 * Returns whether the payload is an array
 *
 * @param {any} payload
 * @returns {payload is any[]}
 */
export function isArray(payload: any): payload is any[] {
  return getType(payload) === 'Array'
}

/**
 * Returns whether the payload is a an array with at least 1 item
 *
 * @param {*} payload
 * @returns {payload is any[]}
 */
export function isFullArray(payload: any): payload is any[] {
  return isArray(payload) && payload.length > 0
}

/**
 * Returns whether the payload is a an empty array
 *
 * @param {*} payload
 * @returns {payload is []}
 */
export function isEmptyArray(payload: any): payload is [] {
  return isArray(payload) && payload.length === 0
}

/**
 * Returns whether the payload is a string
 *
 * @param {*} payload
 * @returns {payload is string}
 */
export function isString(payload: any): payload is string {
  return getType(payload) === 'String'
}

/**
 * Returns whether the payload is a string, BUT returns false for ''
 *
 * @param {*} payload
 * @returns {payload is string}
 */
export function isFullString(payload: any): payload is string {
  return isString(payload) && payload !== ''
}

/**
 * Returns whether the payload is ''
 *
 * @param {*} payload
 * @returns {payload is string}
 */
export function isEmptyString(payload: any): payload is string {
  return payload === ''
}

/**
 * Returns whether the payload is a number (but not NaN)
 *
 * This will return `false` for `NaN`!!
 *
 * @param {*} payload
 * @returns {payload is number}
 */
export function isNumber(payload: any): payload is number {
  return getType(payload) === 'Number' && !isNaN(payload)
}

/**
 * Returns whether the payload is a boolean
 *
 * @param {*} payload
 * @returns {payload is boolean}
 */
export function isBoolean(payload: any): payload is boolean {
  return getType(payload) === 'Boolean'
}

/**
 * Returns whether the payload is a regular expression (RegExp)
 *
 * @param {*} payload
 * @returns {payload is RegExp}
 */
export function isRegExp(payload: any): payload is RegExp {
  return getType(payload) === 'RegExp'
}

/**
 * Returns whether the payload is a Map
 *
 * @param {*} payload
 * @returns {payload is Map}
 */
export function isMap(payload: any): payload is Map {
  return getType(payload) === 'Map'
}

/**
 * Returns whether the payload is a WeakMap
 *
 * @param {*} payload
 * @returns {payload is WeakMap}
 */
export function isWeakMap(payload: any): payload is WeakMap {
  return getType(payload) === 'WeakMap'
}

/**
 * Returns whether the payload is a Set
 *
 * @param {*} payload
 * @returns {payload is Set}
 */
export function isSet(payload: any): payload is Set {
  return getType(payload) === 'Set'
}

/**
 * Returns whether the payload is a WeakSet
 *
 * @param {*} payload
 * @returns {payload is WeakSet}
 */
export function isWeakSet(payload: any): payload is WeakSet {
  return getType(payload) === 'WeakSet'
}

/**
 * Returns whether the payload is a Symbol
 *
 * @param {*} payload
 * @returns {payload is symbol}
 */
export function isSymbol(payload: any): payload is symbol {
  return getType(payload) === 'Symbol'
}

/**
 * Returns whether the payload is a Date, and that the date is valid
 *
 * @param {*} payload
 * @returns {payload is Date}
 */
export function isDate(payload: any): payload is Date {
  return getType(payload) === 'Date' && !isNaN(payload)
}

/**
 * Returns whether the payload is a Blob
 *
 * @param {*} payload
 * @returns {payload is Blob}
 */
export function isBlob(payload: any): payload is Blob {
  return getType(payload) === 'Blob'
}

/**
 * Returns whether the payload is a File
 *
 * @param {*} payload
 * @returns {payload is File}
 */
export function isFile(payload: any): payload is File {
  return getType(payload) === 'File'
}

/**
 * Returns whether the payload is a Promise
 *
 * @param {*} payload
 * @returns {payload is Promise}
 */
export function isPromise(payload: any): payload is Promise {
  return getType(payload) === 'Promise'
}

/**
 * Returns whether the payload is an Error
 *
 * @param {*} payload
 * @returns {payload is Error}
 */
export function isError(payload: any): payload is Error {
  return getType(payload) === 'Error'
}

/**
 * Returns whether the payload is literally the value `NaN` (it's `NaN` and also a `number`)
 *
 * @param {*} payload
 * @returns {payload is typeof NaN}
 */
export function isNaNValue(payload: any): payload is typeof NaN {
  return getType(payload) === 'Number' && isNaN(payload)
}

/**
 * Returns whether the payload is a primitive type (eg. Boolean | Null | Undefined | Number | String | Symbol)
 *
 * @param {*} payload
 * @returns {(payload is boolean | null | undefined | number | string | symbol)}
 */
export function isPrimitive(
  payload: any
): payload is boolean | null | undefined | number | string | symbol {
  return (
    isBoolean(payload) ||
    isNull(payload) ||
    isUndefined(payload) ||
    isNumber(payload) ||
    isString(payload) ||
    isSymbol(payload)
  )
}

/**
 * Returns true whether the payload is null or undefined
 *
 * @param {*} payload
 * @returns {(payload is null | undefined)}
 */
export const isNullOrUndefined = isOneOf(isNull, isUndefined)

export function isOneOf(
  a: TypeGuard,
  b: TypeGuard
): TypeGuard
export function isOneOf(
  a: TypeGuard,
  b: TypeGuard,
  c: TypeGuard
): TypeGuard
export function isOneOf(
  a: TypeGuard,
  b: TypeGuard,
  c: TypeGuard,
  d: TypeGuard
): TypeGuard
export function isOneOf(
  a: TypeGuard,
  b: TypeGuard,
  c: TypeGuard,
  d: TypeGuard,
  e: TypeGuard
): TypeGuard
export function isOneOf(
  a: AnyFunction,
  b: AnyFunction,
  c?: AnyFunction,
  d?: AnyFunction,
  e?: AnyFunction
): (value: unknown) => boolean {
  return (value) =>
    a(value) || b(value) || (!!c && c(value)) || (!!d && d(value)) || (!!e && e(value))
}

/**
 * Does a generic check to check that the given payload is of a given type.
 * In cases like Number, it will return true for NaN as NaN is a Number (thanks javascript!);
 * It will, however, differentiate between object and null
 *
 * @template T
 * @param {*} payload
 * @param {T} type
 * @throws {TypeError} Will throw type error if type is an invalid type
 * @returns {payload is T}
 */
export function isType(payload: any, type: T): payload is T {
  if (!(type instanceof Function)) {
    throw new TypeError('Type must be a function')
  }
  if (!Object.prototype.hasOwnProperty.call(type, 'prototype')) {
    throw new TypeError('Type is not a class')
  }
  // Classes usually have names (as functions usually have names)
  const name: string | undefined | null = (type as any).name
  return getType(payload) === name || Boolean(payload && payload.constructor === type)
}