Kotlin Everywhere Bandung 28 September 2019

1. Bukalapak
Android library for unit testing.
28 September 2019
Mocking Library for
Kotlin

2. Bukalapak
Insert 1x1 photo here
Yuda Oktavian
Android Developer
Who am i?
https://id.linkedin.com/in/yudaoktaviankrisendi
@Yoktavian

3. WHY WE NEED UNIT TESTING?

4. Mockk
Dummy
class/object
should set behavior
with `every` block
before calling method
Spyk
Real
class/object
Can calling method
instantly without `every`
block
BukalapakKinds

5. Unordered
Ordered
Sequential
VERIFICATION
All
01
02
03
04
BukalapakKinds

6. Bukalapak
Unordered Verification
Guarantees that calls were happening
without regard to order.
Sample
verify { actions.fetchBallance() }
Guarantees method fetchBallance() called at least once.

7. Bukalapak
All Verification
Verifies that all calls (multiple method)
happened without checking its order.
Sample
verifyAll {
actions.fetchBalance()
view.renderBalance()
}
Guarantees all methods called, ignore the order and
sequence.

8. Bukalapak
Sequence Verification
The way to verified the exact
sequence of method called. No gaps
please!
Sample
verifySequence {
actions.fetchBalance()
view.renderLoading()
view.renderBalance()
}
Guarantees all methods called based on sequence. It's
strict, but nice to make a clear test.

9. fetchBalance() renderLoading() renderBalance()
No Gaps, Right orderSuccess:
Bukalapak
Sequence Verification

10. fetchBalance() renderLoading()renderBalance()
Wrong sequenceError:
Bukalapak
Sequence Verification

11. fetchBalance() renderBalance()
Bukalapak
Sequence Verification
Right order but there is gapsError:

12. Bukalapak
Order Verification
Verifies only the order of calls that
happened, allowing gaps in the
sequence of calls.
Sample
verifyOrder {
actions.fetchBalance()
view.renderLoading()
view.renderBalance()
}
verifyOrder {
actions.fetchBalance()
view.renderBalance()
}

13. fetchBalance() renderLoading() renderBalance()
Allowing GapsNote:
Bukalapak
Order Verification

14. fetchBalance() renderBalance()
Right order, gaps is okSuccess:
Bukalapak
Order Verification

15. renderBalance() fetchBalance()
Gaps is ok, wrong orderError:
Bukalapak
Order Verification

16. validator
Verify Verify(atLeast=n) Verify(atMost=n)
Verify(exactly=n) Verify(exactly=0)
atLeast atMost
Excactly No calls?
Bukalapak

17. Bukalapak
Verification Confirmation
To double check that all calls were
verified by verify.
Sample
view.renderLoading()
view.renderBalance()
verifyAll {
view.renderLoading()
view.renderBalance()
}
confirmVerified (view)
Result: Success

18. Bukalapak
Sample
view.renderLoading()
view.renderBalance()
verifyAll {
view.renderLoading()
}
confirmVerified (view)
Result: Error

19. Thank you
"Stick to strict mocking for nice and clear tests"
@YannickDeTurck
Yuda Oktavian
Android Developer
Bukalapak