SwiftyMocky

Overview

SwiftyMocky is Lightweight, strongly typed framework for Mockito-like unit testing experience. As Swift doesn’t support reflections well enough to allow building mocks in runtime, library depends on Sourcery, that scans your source code and generates Swift code for you.

The idea of SwiftyMokcy is to mock Swift protocols. The main features are:

  • easy syntax, utilizing full power of auto-complete, which makes writing test easier and faster
  • mock implementations generation
  • a way to specify what mock will return (given)
  • possibility to specify different return values for different attributes
  • verify, whether a method was called on mock or not
  • check method invocations with specified attributes

1. Generating mocks implementations:

One of the boilerplate part of testing and development is writing and updating mocks accordingly to newest changes. SwiftyMocky is capable of generating mock implementations (with configurable behavior), based on protocol definition.

During development process it is possible to use SwiftyMocky in a watcher mode, which will observe changes in you project files, and regenerate files on the fly.

Generating mock

By default, all protocols marked as AutoMockable (inheriting from dummy protocol AutoMockable or annotated with //sourcery: AutoMockable) are being subject of mock implementation generation. All mocks goes to Mock.generated.swift, which can be imported into test target.

2. Stubbing return values for mock methods - Given

All mocks has given method (accessible both as instance method or global function), with easy to use syntax, allowing to specify what should be return values for given methods (based on specified attributes).

Generating mock

All protocol methods are nicely put into MethodProxy, with matching signature. That allows to use auto-complete (just type .) to see all mocked protocol methods, and specify return value for them.

All method attributes are wrapped as Parameter enum, allowing to choose between any and value, giving great flexibility to mock behaviour. Please consider following:

Given(mock, .surname(for name: .value("Johnny"), willReturn: "Bravo"))
Given(mock, .surname(for name: .any(String.self), willReturn: "Kowalsky"))

print(mock.surname(for: "Johny")) // Bravo
print(mock.surname(for: "Mathew")) // Kowalsky
print(mock.surname(for: "Joanna")) // Kowalsky

3. Check invocations of methods - Verify

All mocks has verify method (accessible both as instance method or global function), with easy to use syntax, allowing to verify, whether a method was called on mock, and how many times. It also provides convenient way to specify, whether method attributes matters (and which ones).

Generating mock

All protocol methods are nicely put into VerificationProxy, with matching signature. That allows to use auto-complete (just type .) to see all mocked protocol methods, and specify which one we want to verify.

All method attributes are wrapped as Parameter enum, allowing to choose between any and value, giving great flexibility to tests. Please consider following:

// inject mock to sut. Every time sut saves user data, it should trigger storage storeUser method
sut.usersStorage = mockStorage
sut.saveUser(name: "Johny", surname: "Bravo")
sut.saveUser(name: "Johny", surname: "Cage")
sut.saveUser(name: "Jon", surname: "Snow")

// check if Jon Snow was stored at least one time
Verify(mockStorage, .storeUser(name: .value("Jon"), surname: .value("Snow")))
// storeUser method should be triggered 3 times in total, regardless of attributes values
Verify(mockStorage, 3, .storeUser(name: .any, surname: .any))
// storeUser method should be triggered 2 times with name Johny
Verify(mockStorage, 2, .storeUser(name: .value("Johny"), surname: .any))

Current version

Master branch is still in beta, breaking changes are possible.

Authors

License

SwiftyMocky is available under the MIT license. See the LICENSE file for more info.