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import { maybe } from './maybe.js'
const WHEN_IF = 'WHEN_IF'const WHEN_ELSE = 'WHEN_ELSE'
test('prevent type error', () => {  const x = 5  const y = null  const ifRule = x > 3
  const result = maybe(    ifRule, WHEN_IF, () => y.a === 'foo'  )
  expect(result).toBe(WHEN_IF)})
test('whenElse is a function', () => {  const x = 2  const y = { a : 1 }  const ifRule = x > 3
  const result = maybe(    ifRule, WHEN_IF, () => y.a === 'foo'  )
  expect(result).toBeFalse()})
test('whenIf', () => {  const x = 5  const ifRule = x > 3
  const result = maybe(    ifRule, WHEN_IF, WHEN_ELSE  )
  expect(result).toBe(WHEN_IF)})
test('whenIf is a function', () => {  const x = 5  const ifRule = () => x > 3
  const result = maybe(    ifRule, () => WHEN_IF, WHEN_ELSE  )
  expect(result).toBe(WHEN_IF)})
test('whenElse', () => {  const x = 1  const ifRule = x > 3
  const result = maybe(    ifRule, WHEN_IF, WHEN_ELSE  )
  expect(result).toBe(WHEN_ELSE)})