Write Unit Tests for Business Logic

.gitignore

@@ -123,4 +123,6 @@ app.*.map.json
 !.vscode/extensions.json
 !.vscode/launch.json
 !.idea/codeStyles/
-!.idea/dictionaries/
+!.idea/dictionaries/
+# No need to push mock files since they will be generated automatically while building
+*.mocks.dart

pubspec.lock

@@ -750,6 +750,13 @@ packages:
       url: "https://pub.dartlang.org"
     source: hosted
     version: "1.0.1"
+  mockito:
+    dependency: "direct main"
+    description:
+      name: mockito
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "5.1.0"
   mocktail:
     dependency: transitive
     description:

pubspec.yaml

@@ -45,6 +45,7 @@ dependencies:
     path: ./praxis_flutter_domain
   praxis_data:
     path: ./praxis_data
+  mockito: ^5.1.0
 
 
 dev_dependencies:

test/praxis_flutter_domain/lib/use_cases/get_five_random_jokes_usecase_should.dart

@@ -0,0 +1,62 @@
+import 'package:flutter_test/flutter_test.dart';
+import 'package:mockito/annotations.dart';
+import 'package:mockito/mockito.dart';
+import 'package:praxis_data/sources/network/exceptions/api_exception.dart';
+import 'package:praxis_flutter_domain/entities/api_response.dart'
+    as api_response;
+import 'package:praxis_flutter_domain/entities/jokes/dm_joke_list.dart';
+import 'package:praxis_flutter_domain/repositories/jokes/jokes_repository.dart';
+import 'package:praxis_flutter_domain/use_cases/get_five_random_jokes_usecase.dart';
+
+import 'get_five_random_jokes_usecase_should.mocks.dart';
+
+@GenerateMocks([JokesRepository])
+void main() {
+  late MockJokesRepository _mockJokesRepo;
+  late GetFiveRandomJokesUseCase _sut;
+
+  setUp(
+    () {
+      _mockJokesRepo = MockJokesRepository();
+      _sut = GetFiveRandomJokesUseCase(_mockJokesRepo);
+    },
+  );
+
+  test(
+    "return five random jokes on success API response",
+    () async {
+      var testApiResponse =
+          api_response.Success(data: JokesListWithType("testType", []));
+
+      when(_mockJokesRepo.getFiveRandomJokes())
+          .thenAnswer((realInvocation) async => testApiResponse);
+
+      _sut.perform((data) {
+        if (data != null) {
+          expect(data.jokeList, testApiResponse);
+        }
+      }, (Object error) {}, () {});
+    },
+  );
+
+  test(
+    "return error on failure API response",
+    () async {
+      var testApiResponse = api_response.Failure<JokesListWithType>(
+          error: APIException("testException", 404, "testStatus"));
+
+      when(_mockJokesRepo.getFiveRandomJokes())
+          .thenAnswer((realInvocation) async => testApiResponse);
+
+      _sut.perform((data) {
+        if (data != null) {
+          expect(
+              ((data.jokeList as api_response.Failure<JokesListWithType>).error
+                      as APIException)
+                  .statusCode,
+              404);
+        }
+      }, (Object error) {}, () {});
+    },
+  );
+}

test/praxis_flutter_domain/lib/use_cases/login_use_case_should.dart

@@ -0,0 +1,37 @@
+import 'package:flutter_test/flutter_test.dart';
+import 'package:mockito/annotations.dart';
+import 'package:mockito/mockito.dart';
+import 'package:praxis_flutter_domain/entities/login_request.dart';
+import 'package:praxis_flutter_domain/entities/login_result.dart';
+import 'package:praxis_flutter_domain/repositories/login_repo.dart';
+import 'package:praxis_flutter_domain/use_cases/login_use_case.dart';
+
+import 'login_use_case_should.mocks.dart';
+
+@GenerateMocks([LoginRepo])
+void main() {
+  late MockLoginRepo _mockLoginRepo;
+  late LoginUseCase _sut;
+
+  setUp(
+    () {
+      _mockLoginRepo = MockLoginRepo();
+      _sut = LoginUseCase(_mockLoginRepo);
+    },
+  );
+
+  test(
+    "return login result on valid email and password",
+    () {
+      when(_mockLoginRepo.login("testUsername", "testPassword"))
+          .thenAnswer((_) async => const LoginResult("testJwt", "testToken"));
+
+      _sut.perform((event) {
+        if (event != null) {
+          expect(event, const LoginResult("testJwt", "testToken"));
+        }
+      }, (Object error) {}, () {},
+          LoginRequest("testUsername", "testPassword"));
+    },
+  );
+}