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import { is } from './is'
test('works with built-in types', () => {  expect(is(Array, undefined)).toBeFalse()  expect(is(Array)([])).toBeTrue()  expect(is(Boolean, new Boolean(false))).toBeTrue()  expect(is(Date, new Date())).toBeTrue()  expect(is(Function, () => {})).toBeTrue()  expect(is(Number, new Number(0))).toBeTrue()  expect(is(Object, {})).toBeTrue()  expect(is(RegExp, /(?:)/)).toBeTrue()  expect(is(String, new String(''))).toBeTrue()})
test('works with user-defined types', () => {  function Foo(){}  function Bar(){}  Bar.prototype = new Foo()
  const foo = new Foo()  const bar = new Bar()
  expect(is(Foo, foo)).toBeTrue()  expect(is(Bar, bar)).toBeTrue()  expect(is(Foo, bar)).toBeTrue()  expect(is(Bar, foo)).toBeFalse()})
test('does not coerce', () => {  expect(is(Boolean, 1)).toBeFalse()  expect(is(Number, '1')).toBeFalse()  expect(is(Number, false)).toBeFalse()})
test('recognizes primitives as their object equivalents', () => {  expect(is(Boolean, false)).toBeTrue()  expect(is(Number, 0)).toBeTrue()  expect(is(String, '')).toBeTrue()})
test('does not consider primitives to be instances of Object', () => {  expect(is(Object, false)).toBeFalse()  expect(is(Object, 0)).toBeFalse()  expect(is(Object, '')).toBeFalse()})