With lazy loading of contributions (#3566)

app/src/test/kotlin/fr/free/nrw/commons/utils/NetworkUtilsTest.java

@@ -6,6 +6,7 @@ import android.net.ConnectivityManager;
 import android.net.NetworkInfo;
 import android.telephony.TelephonyManager;
 
+import org.jetbrains.annotations.NotNull;
 import org.junit.Before;
 import org.junit.Test;
 
@@ -28,34 +29,30 @@ public class NetworkUtilsTest {
 
     @Test
     public void testInternetConnectionEstablished() {
-        Context mockContext = mock(Context.class);
-        Application mockApplication = mock(Application.class);
-        ConnectivityManager mockConnectivityManager = mock(ConnectivityManager.class);
-        NetworkInfo mockNetworkInfo = mock(NetworkInfo.class);
-        when(mockNetworkInfo.isConnectedOrConnecting())
-                .thenReturn(true);
-        when(mockConnectivityManager.getActiveNetworkInfo())
-                .thenReturn(mockNetworkInfo);
-        when(mockApplication.getSystemService(Context.CONNECTIVITY_SERVICE))
-                .thenReturn(mockConnectivityManager);
-        when(mockContext.getApplicationContext()).thenReturn(mockApplication);
+        Context mockContext = getContext(true);
         boolean internetConnectionEstablished = NetworkUtils.isInternetConnectionEstablished(mockContext);
         assertTrue(internetConnectionEstablished);
     }
 
-    @Test
-    public void testInternetConnectionNotEstablished() {
+    @NotNull
+    public static Context getContext(boolean connectionEstablished) {
         Context mockContext = mock(Context.class);
         Application mockApplication = mock(Application.class);
         ConnectivityManager mockConnectivityManager = mock(ConnectivityManager.class);
         NetworkInfo mockNetworkInfo = mock(NetworkInfo.class);
         when(mockNetworkInfo.isConnectedOrConnecting())
-                .thenReturn(false);
+            .thenReturn(connectionEstablished);
         when(mockConnectivityManager.getActiveNetworkInfo())
-                .thenReturn(mockNetworkInfo);
+            .thenReturn(mockNetworkInfo);
         when(mockApplication.getSystemService(Context.CONNECTIVITY_SERVICE))
-                .thenReturn(mockConnectivityManager);
+            .thenReturn(mockConnectivityManager);
         when(mockContext.getApplicationContext()).thenReturn(mockApplication);
+        return mockContext;
+    }
+
+    @Test
+    public void testInternetConnectionNotEstablished() {
+        Context mockContext = getContext(false);
         boolean internetConnectionEstablished = NetworkUtils.isInternetConnectionEstablished(mockContext);
         assertFalse(internetConnectionEstablished);
     }

app/src/test/kotlin/fr/free/nrw/commons/utils/PagedListMock.kt

@@ -0,0 +1,74 @@
+package fr.free.nrw.commons.utils
+
+
+import android.database.Cursor
+import androidx.lifecycle.LiveData
+import androidx.paging.DataSource
+import androidx.paging.LivePagedListBuilder
+import androidx.paging.PagedList
+import androidx.room.InvalidationTracker
+import androidx.room.RoomDatabase
+import androidx.room.RoomSQLiteQuery
+import androidx.room.paging.LimitOffsetDataSource
+import com.nhaarman.mockitokotlin2.whenever
+import org.mockito.Mockito.mock
+
+fun <T> List<T>.asPagedList(config: PagedList.Config? = null): LiveData<PagedList<T>> {
+    val defaultConfig = PagedList.Config.Builder()
+        .setEnablePlaceholders(false)
+        .setPageSize(size)
+        .setMaxSize(size + 2)
+        .setPrefetchDistance(1)
+        .build()
+    return LivePagedListBuilder<Int, T>(
+        createMockDataSourceFactory(this),
+        config ?: defaultConfig
+    ).build()
+}
+
+/**
+ * Provides a mocked instance of the data source factory
+ */
+fun <T> createMockDataSourceFactory(itemList: List<T>): DataSource.Factory<Int, T> =
+    object : DataSource.Factory<Int, T>() {
+        override fun create(): DataSource<Int, T> = MockLimitDataSource(itemList)
+    }
+
+/**
+ * Provides a mocked Room SQL query
+ */
+private fun mockQuery(): RoomSQLiteQuery? {
+    val query = mock(RoomSQLiteQuery::class.java);
+    whenever(query.sql).thenReturn("");
+    return query;
+}
+
+/**
+ * Provides a mocked Room DB
+ */
+private fun mockDb(): RoomDatabase? {
+    val roomDatabase = mock(RoomDatabase::class.java);
+    val invalidationTracker = mock(InvalidationTracker::class.java)
+    whenever(roomDatabase.invalidationTracker).thenReturn(invalidationTracker);
+    return roomDatabase;
+}
+
+/**
+ * Class that defines the mocked data source
+ */
+class MockLimitDataSource<T>(private val itemList: List<T>) :
+    LimitOffsetDataSource<T>(mockDb(), mockQuery(), false, null) {
+    override fun convertRows(cursor: Cursor?): MutableList<T> = itemList.toMutableList()
+    override fun countItems(): Int = itemList.count()
+    override fun isInvalid(): Boolean = false
+    override fun loadRange(params: LoadRangeParams, callback: LoadRangeCallback<T>) {
+    }
+
+    override fun loadRange(startPosition: Int, loadCount: Int): MutableList<T> {
+        return itemList.subList(startPosition, startPosition + loadCount).toMutableList()
+    }
+
+    override fun loadInitial(params: LoadInitialParams, callback: LoadInitialCallback<T>) {
+        callback.onResult(itemList, 0)
+    }
+}