BDD for iOSby JMac

What is BDD?

“Behavior Driven Development”

Why BDD?

“Because we want to the way our system behaves, not how it is implemented.”

–J.B. Rainsberger

“Integration tests are a scam.”

Sales Demo

How do I practice BDD for iOS?

“Cedar”

What is Cedar?

“a BDD-style Objective-C testing framework with matchers and test doubles.”

How do I install Cedar?

“With CocoaPods”

What is CocoaPods?

“CocoaPods is a dependency manager for Swift and Objective-C Cocoa projects, which automates

and simplifies the process of using 3rd-party libraries in your projects.”

How do I use CocoaPods?

gem install cocoapods

pod init

The Podfileplatform :ios, '8.1'

target 'parked' do

pod 'Blindside'

pod 'Flurry-iOS-SDK'

end

target 'Specs' do

pod 'Blindside'

pod 'Cedar', git: 'https://github.com/pivotal/cedar.git'

pod 'PivotalCoreKit/Development', :git => 'https://github.com/pivotal/PivotalCoreKit.git'

end

Project Type

Minimum SDK

Targets

Package/Pod

How do I install/update the pods?

pod install

Is that it?

“No.”

A few gotchas…

❖ You’ll want to close Xcode while managing Pods

❖ You’ll need to create any additional targets referenced in the Podfile

❖ Once you install Pods, you need to open the Xcode workspace

Setup Demo

The anatomy of a Spec file

❖ describe

❖ it

❖ beforeEach

❖ context

❖ and more (but not today)

describe

// group specs together

describe(@"the thing your testing", ^{

// test goes here code

});

it

// the test, expectation, or "spec"

it(@"should do the thing", ^{

expected should equal(actual);

});

beforeEach

// runs before each spec in the current block

beforeEach(^{

subject = [SomeViewController alloc] init];

});

context

// group specs together based on state

context(@"when user is logged in", ^{

// test code

});

context(@"when user is logged out", ^{

// test code

});

Full Exampledescribe(@"tapping the save button", ^{ context(@"when the fields have input", ^{ it(@"should store the input in the database", ^{

// example });

it(@"should call the delegate", ^{ // example

}); });

context(@"when the fields do not have input", ^{ it(@"should show an alert", ^{

// example }); }); });

Matchers

❖ should and should_not

❖ equal

❖ be_nil, be_truthy, be_falsy, be_empty

❖ be_greater_than, be_less_than, etc

❖ be_same_instance_as, be_instance_of

Example

person.name should equal(@"JMac");

person.name should_not be_nil;

person.name.length should be_less_than(@5);

person should be_instance_of([Person class]);

person should be_same_instance_as(person);

Test Doubles (fakes)

❖ fake_for creates a test double of an object so its methods can be stubbed

❖ nice_fake_for creates a test double of an object with all its methods stubbed to return nil

ExamplefakePerson = fake_for([Person class]);

fakePerson.name; // exception

niceFakePerson = nice_fake_for([Person class]);

niceFakePerson.name; // nil

niceFakePerson stub_method(@selector(name))

.and_return(@"JMac");

niceFakePerson.name; // @"JMac"

Code Demo

Resources

❖ CocoaPods

❖ Cedar

❖ Blindside

❖ Thrust

❖ Follow me on Twitter: @gonedark