import pytest
import capnp
import os

this_dir = os.path.dirname(__file__)

@pytest.fixture
def addressbook():
     return capnp.load(os.path.join(this_dir, 'addressbook.capnp'))

def test_addressbook(addressbook):
    def writeAddressBook(fd):
        message = capnp.MallocMessageBuilder()
        addressBook = message.initRoot(addressbook.AddressBook)
        people = addressBook.init('people', 2)

        alice = people[0]
        alice.id = 123
        alice.name = 'Alice'
        alice.email = 'alice@example.com'
        alicePhones = alice.init('phones', 1)
        alicePhones[0].number = "555-1212"
        alicePhones[0].type = 'mobile'
        alice.employment.school = "MIT"

        bob = people[1]
        bob.id = 456
        bob.name = 'Bob'
        bob.email = 'bob@example.com'
        bobPhones = bob.init('phones', 2)
        bobPhones[0].number = "555-4567"
        bobPhones[0].type = 'home'
        bobPhones[1].number = "555-7654"
        bobPhones[1].type = 'work'
        bob.employment.unemployed = None

        capnp.writePackedMessageToFd(fd, message)


    def printAddressBook(fd):
        message = capnp.PackedFdMessageReader(f.fileno())
        addressBook = message.getRoot(addressbook.AddressBook)

        for person in addressBook.people:
            print(person.name, ':', person.email)
            for phone in person.phones:
                print(phone.type, ':', phone.number)

            which = person.employment.which()
            print(which)

            if which == 'unemployed':
                print('unemployed')
            elif which == 'employer':
                print('employer:', person.employment.employer)
            elif which == 'school':
                print('student at:', person.employment.school)
            elif which == 'selfEmployed':
                print('self employed')
            print()


    f = open('example', 'w')
    writeAddressBook(f.fileno())

    f = open('example', 'r')
    printAddressBook(f.fileno())

Add regression test