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import { always } from './always.js'import { cond } from './cond.js'import { equals } from './equals.js'import { T } from './T.js'
test('returns a function', () => {  expect(typeof cond([])).toBe('function')})
test('returns a conditional function', () => {  const fn = cond([    [ equals(0), always('water freezes at 0°C') ],    [ equals(100), always('water boils at 100°C') ],    [      T,      function (temp){        return 'nothing special happens at ' + temp + '°C'      },    ],  ])  expect(fn(0)).toBe('water freezes at 0°C')  expect(fn(50)).toBe('nothing special happens at 50°C')  expect(fn(100)).toBe('water boils at 100°C')})
test('no winner', () => {  const fn = cond([    [ equals('foo'), always(1) ],    [ equals('bar'), always(2) ],  ])  expect(fn('quux')).toBeUndefined()})
test('predicates are tested in order', () => {  const fn = cond([    [ T, always('foo') ],    [ T, always('bar') ],    [ T, always('baz') ],  ])  expect(fn()).toBe('foo')})
test('pass all inputs',() => {  cond([ [()=> true, (...x) => {    expect(x).toEqual([1,2,3])  }] ])(1,2,3)})