Better tests with fongo

Doug Roper

fongo

Fake Mongo.

In memory.

Crazy fast.

Awesome logging.

Fongo + Untestable -> Testable.

Fongo + Testable -> Better.

how do we unit test collections?

def afterAll() = clinicalDataCollection.collection.drop()

def beforeEach() = clinicalDataCollection.remove()

def testSavingMeasurements = {
  val measurements = ...
  
  clinicalDataCollection.saveMeasurements(measurements) 
  val persisted = clinicalDataCollection.find(measurements.id)
 
  assert(persisted === measurements)
  
}

test on jenkins

Install Mongo on Jenkins.

No isolation.

Workarounds:

src/it/test
one job per mongo

Demo

SurveyDefinitionCollectionTest

mocks are brittle

class PonyService(...) {  def bestPony(): Pony = ponyDAO.find(bestQuery).head}

@Test def testPonyService() {
  val mockPonyDAO = mock[PonyDAO]
  when(mockPonyDAO.find()).thenReturn(Seq(new Pony("Pinkie Pie")))

  val service = new PonyService(mockPonyDAO)

  val pony = service.bestPony()
  assert(pony.name === "Pinkie Pie")
}

Better tests with fongo

fongo

how do we unit test collections?

test on jenkins

Demo

mocks are brittle

Fake > Mock

Build failed

1. bad code

2. bad test