describe('findAndValidateUser', () => {
  const users = [
    { id: 1, name: 'Alice', age: 25 },
    { id: 2, name: 'Bob', age: 16 },
    { id: 3, name: 'Charlie', age: 30 },
  ]

  it('returns right with user if valid and adult', () => {
    const result = findAndValidateUser(1, users)
    expect(result).toEqual({ _tag: 'Right', right: { id: 1, name: 'Alice', age: 25 } })
  })

  it('returns left if ID is invalid', () => {
    const result = findAndValidateUser(0, users)
    expect(result).toEqual({ _tag: 'Left', left: 'Invalid ID' })
  })

  it('returns left if user not found', () => {
    const result = findAndValidateUser(99, users)
    expect(result).toEqual({ _tag: 'Left', left: 'User not found' })
  })

  it('returns left if user too young', () => {
    const result = findAndValidateUser(2, users)
    expect(result).toEqual({ _tag: 'Left', left: 'User too young' })
  })
})