Create tests (#26)

* Add unit and instrumented tests
* Divide code coverage to two different tags on codecov
* Change sdk image to 25
* Turn on console output in unit tests

.circleci/config.yml

@@ -7,7 +7,7 @@ references:
 
   container_config: &container_config
     docker:
-      - image: circleci/android:api-25-alpha
+      - image: circleci/android:api-26-alpha
     working_directory: *workspace_root
     environment:
       environment:
@@ -33,7 +33,7 @@ jobs:
           command: ./gradlew --no-daemon --stacktrace dependencies || true
       - run:
           name: Initial build
-          command: ./gradlew --no-daemon --stacktrace assembleDebug
+          command: ./gradlew --no-daemon --stacktrace assembleDebug -PdisablePreDex
       - store_artifacts:
           path: ./app/build/outputs/apk/
           destination: apks/
@@ -58,6 +58,8 @@ jobs:
       - store_artifacts:
           path: ./app/build/reports/
           destination: lint_reports/app/
+      - store_test_results:
+          path: ./app/build/reports/
 
   test:
     <<: *container_config
@@ -69,8 +71,10 @@ jobs:
           name: Run Tests
           command: ./gradlew --no-daemon --stacktrace test
       - run:
-          name: Upload code coverage to codecov
+          name: Upload unit code coverage to codecov
-          command: ./gradlew --no-daemon --stacktrace jacocoTestReport && bash <(curl -s https://codecov.io/bash)
+          command: |
+            ./gradlew --no-daemon --stacktrace jacocoTestReport
+            bash <(curl -s https://codecov.io/bash) -F unit
       - run:
           name: Upload code coverage to codacy
           command: ./gradlew --no-daemon --stacktrace codacyUpload
@@ -83,6 +87,43 @@ jobs:
       - store_test_results:
           path: ./app/build/test-results
 
+  instrumented:
+    <<: *container_config
+    steps:
+      - *attach_workspace
+      - run:
+          name: Setup emulator
+          command: sdkmanager "system-images;android-19;google_apis;armeabi-v7a" && echo "no" | avdmanager create avd -n test -k "system-images;android-19;google_apis;armeabi-v7a"
+      - run:
+          name: Launch emulator
+          command: export LD_LIBRARY_PATH=${ANDROID_HOME}/emulator/lib64:${ANDROID_HOME}/emulator/lib64/qt/lib && emulator64-arm -avd test -noaudio -no-boot-anim -no-window -accel on
+          background: true
+      - run:
+          name: Wait emulator
+          command: |
+            # wait for it to have booted
+            circle-android wait-for-boot
+            # unlock the emulator screen
+            sleep 30
+            adb shell input keyevent 82
+      - run:
+          name: Clean project
+          command: ./gradlew clean --no-daemon --stacktrace --console=plain -PdisablePreDex
+      - run:
+          name: Run instrumented tests
+          command: ./gradlew connectedAndroidTest --no-daemon --stacktrace --console=plain -PdisablePreDex
+      - run:
+          name: Collect logs from emulator
+          command: adb logcat -d > ./app/build/reports/logcat_emulator.txt
+      - run:
+          name: Upload code covarage to codecov
+          command: bash <(curl -s https://codecov.io/bash) -F instrumented
+      - store_artifacts:
+          path: ./app/build/reports
+          destination: reports
+      - store_test_results:
+          path: ./app/build/outputs/androidTest-results/connected/
+
 workflows:
   version: 2
 
@@ -95,3 +136,6 @@ workflows:
       - test:
           requires:
             - build
+      - instrumented:
+          requires:
+            - build

.codecov.yml

@@ -0,0 +1,19 @@
+coverage:
+  range: 60..100
+  status:
+    project:
+      default: off
+      unit:
+        target: 20%
+        flags: unit
+      instrumented:
+        target: 20%
+        flags: instrumented
+
+flags:
+  unit:
+    paths:
+      - app/src/main/io/github/wulkanowy
+  instrumented:
+    paths:
+      - app/src/main/io/github/wulkanowy

app/build.gradle

@@ -9,7 +9,7 @@ android {
     defaultConfig {
         applicationId "io.github.wulkanowy"
         testApplicationId "io.github.tests.wulkanowy"
-        minSdkVersion 14
+        minSdkVersion 15
         targetSdkVersion 26
         versionCode 1
         versionName "0.1.0"
@@ -26,6 +26,16 @@ android {
             ext.enableCrashlytics = false
         }
     }
+
+    testOptions {
+        unitTests.all {
+            testLogging {
+                events "passed", "skipped", "failed", "standardOut", "standardError"
+                outputs.upToDateWhen {false}
+                showStandardStreams = true
+            }
+        }
+    }
 }
 
 greendao {
@@ -35,9 +45,7 @@ greendao {
 
 dependencies {
     compile fileTree(include: ['*.jar'], dir: 'libs')
-    androidTestCompile('com.android.support.test.espresso:espresso-core:2.2.2', {
+
-        exclude group: 'com.android.support', module: 'support-annotations'
-    })
     compile 'com.android.support:appcompat-v7:26.0.1'
     compile 'com.android.support.constraint:constraint-layout:1.0.2'
     compile 'com.android.support:design:26.0.1'
@@ -45,7 +53,6 @@ dependencies {
     compile 'com.android.support:support-v4:26.0.1'
     compile 'com.android.support:recyclerview-v7:26.0.1'
     compile 'com.android.support:cardview-v7:26.0.1'
-    compile 'com.google.code.gson:gson:2.8.1'
     compile 'com.firebase:firebase-jobdispatcher:0.8.1'
     compile 'com.thoughtbot:expandablerecyclerview:1.3'
     compile 'org.apache.commons:commons-lang3:3.6'
@@ -60,4 +67,12 @@ dependencies {
     
     testCompile 'junit:junit:4.12'
     testCompile 'org.mockito:mockito-core:2.10.0'
+
+    androidTestCompile('com.android.support.test.espresso:espresso-core:3.0.1', {
+        exclude group: 'com.android.support', module: 'support-annotations'
+    })
+    androidTestCompile 'com.android.support:support-annotations:26.0.1'
+    androidTestCompile 'com.android.support.test:runner:1.0.1'
+    androidTestCompile 'com.android.support.test:rules:1.0.1'
+    androidTestCompile 'org.hamcrest:hamcrest-library:1.3'
 }

app/src/androidTest/java/io/github/wulkanowy/ExampleInstrumentedTest.java

@@ -1,26 +0,0 @@
-package io.github.wulkanowy;
-
-import static org.junit.Assert.assertEquals;
-
-import android.content.Context;
-import android.support.test.InstrumentationRegistry;
-import android.support.test.runner.AndroidJUnit4;
-
-import org.junit.Test;
-import org.junit.runner.RunWith;
-
-/**
- * Instrumentation test, which will execute on an Android device.
- *
- * @see <a href="http://d.android.com/tools/testing">Testing documentation</a>
- */
-@RunWith(AndroidJUnit4.class)
-public class ExampleInstrumentedTest {
-    @Test
-    public void useAppContext() throws Exception {
-        // Context of the app under test.
-        Context appContext = InstrumentationRegistry.getTargetContext();
-
-        assertEquals("io.github.wulkanowy", appContext.getPackageName());
-    }
-}

app/src/androidTest/java/io/github/wulkanowy/dao/entities/AccountTest.java

@@ -1,7 +1,10 @@
 package io.github.wulkanowy.dao.entities;
 
+import android.support.test.filters.SmallTest;
+
 import org.greenrobot.greendao.test.AbstractDaoTestLongPk;
 
+@SmallTest
 public class AccountTest extends AbstractDaoTestLongPk<AccountDao, Account> {
 
     public AccountTest() {

app/src/androidTest/java/io/github/wulkanowy/dao/entities/GradeTest.java

@@ -1,7 +1,10 @@
 package io.github.wulkanowy.dao.entities;
 
+import android.support.test.filters.SmallTest;
+
 import org.greenrobot.greendao.test.AbstractDaoTestLongPk;
 
+@SmallTest
 public class GradeTest extends AbstractDaoTestLongPk<GradeDao, Grade> {
 
     public GradeTest() {

app/src/androidTest/java/io/github/wulkanowy/dao/entities/SubjectTest.java

@@ -1,7 +1,10 @@
 package io.github.wulkanowy.dao.entities;
 
+import android.support.test.filters.SmallTest;
+
 import org.greenrobot.greendao.test.AbstractDaoTestLongPk;
 
+@SmallTest
 public class SubjectTest extends AbstractDaoTestLongPk<SubjectDao, Subject> {
 
     public SubjectTest() {

app/src/androidTest/java/io/github/wulkanowy/security/SafetyTest.java

@@ -0,0 +1,25 @@
+package io.github.wulkanowy.security;
+
+import android.content.Context;
+import android.support.test.InstrumentationRegistry;
+import android.support.test.filters.SdkSuppress;
+import android.support.test.filters.SmallTest;
+import android.support.test.runner.AndroidJUnit4;
+
+import org.junit.Assert;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+
+@SmallTest
+@RunWith(AndroidJUnit4.class)
+public class SafetyTest {
+
+    @Test
+    @SdkSuppress(minSdkVersion = 18)
+    public void encryptDecryptTest() throws Exception {
+        Context targetContext = InstrumentationRegistry.getTargetContext();
+
+        Safety safety = new Safety();
+        Assert.assertEquals("PASS", safety.decrypt("TEST", safety.encrypt("TEST", "PASS", targetContext)));
+    }
+}

app/src/androidTest/java/io/github/wulkanowy/security/ScramblerTest.java

@@ -0,0 +1,59 @@
+package io.github.wulkanowy.security;
+
+import android.content.Context;
+import android.os.Build;
+import android.support.test.InstrumentationRegistry;
+import android.support.test.filters.SdkSuppress;
+import android.support.test.filters.SmallTest;
+import android.support.test.runner.AndroidJUnit4;
+
+import org.junit.Assert;
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+
+@SmallTest
+@SdkSuppress(minSdkVersion = 18)
+@RunWith(AndroidJUnit4.class)
+public class ScramblerTest {
+
+    private Context targetContext;
+
+    private Scrambler scramblerLoad = new Scrambler();
+
+    @Before
+    public void setUp() throws CryptoException {
+        targetContext = InstrumentationRegistry.getTargetContext();
+        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN_MR2) {
+            scramblerLoad.loadKeyStore();
+        }
+    }
+
+    @Test(expected = CryptoException.class)
+    @SdkSuppress(maxSdkVersion = 17)
+    public void testNoSuchAlgorithm() throws CryptoException {
+        scramblerLoad.loadKeyStore();
+    }
+
+    @Test
+    public void decryptEncryptStringTest() throws CryptoException {
+        scramblerLoad.generateNewKey("TEST", targetContext);
+        Assert.assertEquals("pass",
+                scramblerLoad.decryptString("TEST", scramblerLoad.encryptString("TEST", "pass")));
+    }
+
+    @Test(expected = CryptoException.class)
+    public void decryptEmptyTest() throws CryptoException {
+        scramblerLoad.decryptString("", "");
+    }
+
+    @Test(expected = CryptoException.class)
+    public void encryptEmptyTest() throws CryptoException {
+        scramblerLoad.encryptString("", "");
+    }
+
+    @Test(expected = CryptoException.class)
+    public void generateNewKeyEmptyTest() throws CryptoException {
+        scramblerLoad.generateNewKey("", targetContext);
+    }
+}

app/src/androidTest/java/io/github/wulkanowy/services/synchronization/AccountSynchronizationTest.java

@@ -72,11 +72,11 @@ public class AccountSynchronizationTest {
     public void loginCurrentUserTest() throws Exception {
         AccountDao accountDao = daoSession.getAccountDao();
 
-        Safety safety = new Safety(context);
+        Safety safety = new Safety();
 
         Long userId = accountDao.insert(new Account()
                 .setEmail("TEST@TEST")
-                .setPassword(safety.encrypt("TEST@TEST", "TEST"))
+                .setPassword(safety.encrypt("TEST@TEST", "TEST", context))
                 .setSymbol(""));
 
         setUserIdSharePreferences(userId);
@@ -117,7 +117,7 @@ public class AccountSynchronizationTest {
         Assert.assertNotNull(loginSession.getDaoSession());
         Assert.assertEquals(loginSession.getVulcan(), vulcan);
 
-        Safety safety = new Safety(context);
+        Safety safety = new Safety();
         Account account = daoSession.getAccountDao().load(userId);
 
         Assert.assertNotNull(account);

app/src/main/java/io/github/wulkanowy/activity/dashboard/DashboardActivity.java

@@ -72,7 +72,7 @@ public class DashboardActivity extends AppCompatActivity {
         navigation.setOnNavigationItemSelectedListener(mOnNavigationItemSelectedListener);
 
         getSupportFragmentManager().beginTransaction()
-                .add(R.id.fragment_container, boardFragment).commit();
+                .replace(R.id.fragment_container, boardFragment).commit();
     }
 
     public void onBackPressed() {

app/src/main/java/io/github/wulkanowy/activity/dashboard/grades/GradesDialogFragment.java

@@ -44,17 +44,17 @@ public class GradesDialogFragment extends DialogFragment {
         dateText.setText(grade.getDate());
         colorText.setText(colorHexToColorName(grade.getColor()));
 
-        if (grade.getDescription().equals("")) {
+        if ("".equals(grade.getDescription())) {
-            if (!grade.getSymbol().equals("")) {
+            if (!"".equals(grade.getSymbol())) {
                 descriptionText.setText(grade.getSymbol());
             }
-        } else if (!grade.getSymbol().equals("")) {
+        } else if (!"".equals(grade.getSymbol())) {
             descriptionText.setText(grade.getSymbol() + " - " + grade.getDescription());
         } else {
             descriptionText.setText(grade.getDescription());
         }
 
-        if (!grade.getTeacher().equals("")) {
+        if (!"".equals(grade.getTeacher())) {
             teacherText.setText(grade.getTeacher());
         }
 
@@ -68,7 +68,7 @@ public class GradesDialogFragment extends DialogFragment {
         return view;
     }
 
-    public int colorHexToColorName(String hexColor) {
+    public static int colorHexToColorName(String hexColor) {
         switch (hexColor) {
             case "000000": {
                 return R.string.color_black_text;

app/src/main/java/io/github/wulkanowy/activity/dashboard/grades/GradesFragment.java

@@ -35,7 +35,8 @@ public class GradesFragment extends Fragment {
 
         DaoSession daoSession = ((WulkanowyApp) getActivity().getApplication()).getDaoSession();
 
-        if (subjectWithGradesList.equals(new ArrayList<>())) {
+        if (new ArrayList<>().equals(subjectWithGradesList)) {
+            createExpListView();
             new GradesTask(daoSession).execute();
         } else if (subjectWithGradesList.size() > 0) {
             createExpListView();
@@ -45,7 +46,7 @@ public class GradesFragment extends Fragment {
         return view;
     }
 
-    public void createExpListView() {
+    private void createExpListView() {
 
         RecyclerView recyclerView = view.findViewById(R.id.subject_grade_recycler);
         recyclerView.setLayoutManager(new LinearLayoutManager(view.getContext()));

app/src/main/java/io/github/wulkanowy/dao/EntitiesCompare.java

@@ -7,7 +7,7 @@ import java.util.List;
 
 import io.github.wulkanowy.dao.entities.Grade;
 
-public class EntitiesCompare {
+public abstract class EntitiesCompare {
 
     public static List<Grade> compareGradeList(List<Grade> newList, List<Grade> oldList) {
 

app/src/main/java/io/github/wulkanowy/security/Safety.java

@@ -9,16 +9,12 @@ import io.github.wulkanowy.utilities.RootUtilities;
 
 public class Safety extends Scrambler {
 
-    public Safety(Context context) {
+    public String encrypt(String email, String plainText, Context context) throws CryptoException, UnsupportedOperationException {
-        super(context);
-    }
-
-    public String encrypt(String email, String plainText) throws CryptoException, UnsupportedOperationException {
 
         if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN_MR2) {
 
             loadKeyStore();
-            generateNewKey(email);
+            generateNewKey(email, context);
             return encryptString(email, plainText);
         } else {
 

app/src/main/java/io/github/wulkanowy/security/Scrambler.java

@@ -29,19 +29,14 @@ import javax.security.auth.x500.X500Principal;
 
 public class Scrambler {
 
-    public final static String DEBUG_TAG = "WulkanowySecurity";
 
     private static final String ANDROID_KEYSTORE = "AndroidKeyStore";
 
-    protected Context context;
+    public final static String DEBUG_TAG = "WulkanowySecurity";
 
     private KeyStore keyStore;
 
-    protected Scrambler(Context context) {
+    public void loadKeyStore() throws CryptoException {
-        this.context = context;
-    }
-
-    protected void loadKeyStore() throws CryptoException {
 
         try {
             keyStore = KeyStore.getInstance(ANDROID_KEYSTORE);
@@ -54,7 +49,7 @@ public class Scrambler {
     }
 
     @TargetApi(18)
-    protected void generateNewKey(String alias) throws CryptoException {
+    protected void generateNewKey(String alias, Context context) throws CryptoException {
 
         Calendar start = Calendar.getInstance();
         Calendar end = Calendar.getInstance();
@@ -62,7 +57,7 @@ public class Scrambler {
         AlgorithmParameterSpec spec;
 
         end.add(Calendar.YEAR, 10);
-        if (!alias.isEmpty()) {
+        if (!"".equals(alias)) {
             try {
                 if (!keyStore.containsAlias(alias)) {
                     if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {

app/src/main/java/io/github/wulkanowy/services/synchronisation/AccountSynchronisation.java

@@ -33,7 +33,7 @@ public class AccountSynchronisation {
 
             Log.d(VulcanSync.DEBUG_TAG, "Login current user id=" + String.valueOf(userId));
 
-            Safety safety = new Safety(context);
+            Safety safety = new Safety();
             Account account = accountDao.load(userId);
             vulcan.login(
                     account.getEmail(),
@@ -60,12 +60,12 @@ public class AccountSynchronisation {
 
         PersonalData personalData = vulcan.getBasicInformation().getPersonalData();
         AccountDao accountDao = daoSession.getAccountDao();
-        Safety safety = new Safety(context);
+        Safety safety = new Safety();
 
         Account account = new Account()
                 .setName(personalData.getFirstAndLastName())
                 .setEmail(email)
-                .setPassword(safety.encrypt(email, password))
+                .setPassword(safety.encrypt(email, password, context))
                 .setSymbol(symbol);
 
         userId = accountDao.insert(account);

app/src/main/java/io/github/wulkanowy/utilities/ConversionVulcanObject.java

@@ -1,7 +1,6 @@
 package io.github.wulkanowy.utilities;
 
 
-import java.text.ParseException;
 import java.util.ArrayList;
 import java.util.List;
 
@@ -25,7 +24,7 @@ public abstract class ConversionVulcanObject {
         return subjectEntityList;
     }
 
-    public static List<Grade> gradesToGradeEntities(List<io.github.wulkanowy.api.grades.Grade> gradeList) throws ParseException {
+    public static List<Grade> gradesToGradeEntities(List<io.github.wulkanowy.api.grades.Grade> gradeList) {
 
         List<Grade> gradeEntityList = new ArrayList<>();
 

app/src/test/java/io/github/wulkanowy/activity/dashboard/grades/GradesDialogFragmentTest.java

@@ -0,0 +1,22 @@
+package io.github.wulkanowy.activity.dashboard.grades;
+
+
+import org.junit.Assert;
+import org.junit.Test;
+
+import io.github.wulkanowy.R;
+
+import static io.github.wulkanowy.activity.dashboard.grades.GradesDialogFragment.colorHexToColorName;
+
+public class GradesDialogFragmentTest {
+
+    @Test
+    public void colorHexToColorNameTest() {
+        Assert.assertEquals(R.string.color_black_text, colorHexToColorName("000000"));
+        Assert.assertEquals(R.string.color_red_text, colorHexToColorName("F04C4C"));
+        Assert.assertEquals(R.string.color_blue_text, colorHexToColorName("20A4F7"));
+        Assert.assertEquals(R.string.color_green_text, colorHexToColorName("6ECD07"));
+        Assert.assertEquals(R.string.noColor_text, colorHexToColorName(""));
+
+    }
+}

app/src/test/java/io/github/wulkanowy/activity/dashboard/grades/SubjectWithGradesTest.java

@@ -0,0 +1,45 @@
+package io.github.wulkanowy.activity.dashboard.grades;
+
+import org.junit.Assert;
+import org.junit.Before;
+import org.junit.Test;
+
+import java.util.ArrayList;
+import java.util.List;
+
+import io.github.wulkanowy.dao.entities.Grade;
+
+public class SubjectWithGradesTest {
+
+    private List<Grade> gradeListEmpty = new ArrayList<>();
+
+    private List<Grade> gradeList = new ArrayList<>();
+
+    private Grade grade = new Grade().setDescription("Lorem ipsum");
+
+    @Before
+    public void setUp() {
+        gradeList.add(grade);
+    }
+
+    @Test
+    public void countTest() {
+        SubjectWithGrades subjectWithGrades = new SubjectWithGrades("", gradeList);
+        Assert.assertEquals(1, subjectWithGrades.getItemCount());
+
+        SubjectWithGrades subjectWithGrades1 = new SubjectWithGrades("", gradeListEmpty);
+        Assert.assertEquals(0, subjectWithGrades1.getItemCount());
+    }
+
+    @Test
+    public void titleTest() {
+        SubjectWithGrades subjectWithGrades = new SubjectWithGrades("TEST", gradeListEmpty);
+        Assert.assertEquals("TEST", subjectWithGrades.getTitle());
+    }
+
+    @Test
+    public void itemTest() {
+        SubjectWithGrades subjectWithGrades = new SubjectWithGrades("", gradeList);
+        Assert.assertEquals(gradeList, subjectWithGrades.getItems());
+    }
+}

app/src/test/java/io/github/wulkanowy/utilities/ConnectionUtilitiesTest.java

@@ -0,0 +1,42 @@
+package io.github.wulkanowy.utilities;
+
+import android.content.Context;
+import android.net.ConnectivityManager;
+import android.net.NetworkInfo;
+
+import org.junit.Assert;
+import org.junit.Test;
+
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.when;
+
+public class ConnectionUtilitiesTest extends ConnectionUtilities {
+
+    @Test
+    public void isOnlineTrueTest() {
+        NetworkInfo networkInfo = mock(NetworkInfo.class);
+        when(networkInfo.isConnectedOrConnecting()).thenReturn(true);
+
+        ConnectivityManager connectivityManager = mock(ConnectivityManager.class);
+        when(connectivityManager.getActiveNetworkInfo()).thenReturn(networkInfo);
+
+        Context context = mock(Context.class);
+        when(context.getSystemService(Context.CONNECTIVITY_SERVICE)).thenReturn(connectivityManager);
+
+        Assert.assertTrue(ConnectionUtilities.isOnline(context));
+    }
+
+    @Test
+    public void isOnlineFalseTest() {
+        NetworkInfo networkInfo = mock(NetworkInfo.class);
+        when(networkInfo.isConnectedOrConnecting()).thenReturn(false);
+
+        ConnectivityManager connectivityManager = mock(ConnectivityManager.class);
+        when(connectivityManager.getActiveNetworkInfo()).thenReturn(networkInfo);
+
+        Context context = mock(Context.class);
+        when(context.getSystemService(Context.CONNECTIVITY_SERVICE)).thenReturn(connectivityManager);
+
+        Assert.assertFalse(ConnectionUtilities.isOnline(context));
+    }
+}

app/src/test/java/io/github/wulkanowy/utilities/ConversionVulcanObjectTest.java

@@ -0,0 +1,45 @@
+package io.github.wulkanowy.utilities;
+
+import org.junit.Assert;
+import org.junit.Test;
+
+import java.util.ArrayList;
+import java.util.List;
+
+import io.github.wulkanowy.api.grades.Grade;
+import io.github.wulkanowy.api.grades.Subject;
+
+public class ConversionVulcanObjectTest extends ConversionVulcanObject {
+
+    @Test
+    public void subjectConversionTest() {
+        List<Subject> subjectList = new ArrayList<>();
+        subjectList.add(new Subject().setName("Matematyka"));
+        List<io.github.wulkanowy.dao.entities.Subject> subjectEntitiesList =
+                ConversionVulcanObject.subjectsToSubjectEntities(subjectList);
+
+        Assert.assertEquals("Matematyka", subjectEntitiesList.get(0).getName());
+    }
+
+    @Test
+    public void subjectConversionEmptyTest() {
+        Assert.assertEquals(new ArrayList<>(),
+                ConversionVulcanObject.subjectsToSubjectEntities(new ArrayList<Subject>()));
+    }
+
+    @Test
+    public void gradesConversionTest() {
+        List<Grade> gradeList = new ArrayList<>();
+        gradeList.add(new Grade().setDescription("Lorem ipsum"));
+        List<io.github.wulkanowy.dao.entities.Grade> gradeEntitiesList =
+                ConversionVulcanObject.gradesToGradeEntities(gradeList);
+
+        Assert.assertEquals("Lorem ipsum", gradeEntitiesList.get(0).getDescription());
+    }
+
+    @Test
+    public void gradeConversionEmptyTest() {
+        Assert.assertEquals(new ArrayList<>(),
+                ConversionVulcanObject.gradesToGradeEntities(new ArrayList<Grade>()));
+    }
+}

build.gradle

@@ -18,6 +18,17 @@ buildscript {
     }
 }
 
+project.ext.preDexLibs = !project.hasProperty("disablePreDex")
+subprojects {
+    project.plugins.whenPluginAdded { plugin ->
+        if ("com.android.build.gradle.AppPlugin" == plugin.class.name) {
+            project.android.dexOptions.preDexLibraries = rootProject.ext.preDexLibs
+        } else if ("com.android.build.gradle.LibraryPlugin" == plugin.class.name) {
+            project.android.dexOptions.preDexLibraries = rootProject.ext.preDexLibs
+        }
+    }
+}
+
 allprojects {
     repositories {
         jcenter()