Added Test for BookmarksPagerAdapter (#4027)

app/src/test/kotlin/fr/free/nrw/commons/bookmarks/BookmarksPagerAdapterTests.kt

@@ -0,0 +1,47 @@
+package fr.free.nrw.commons.bookmarks
+
+import android.content.Context
+import androidx.fragment.app.FragmentManager
+import org.junit.Assert
+import org.junit.Before
+import org.junit.Test
+import org.mockito.Mock
+import org.mockito.MockitoAnnotations
+
+class BookmarksPagerAdapterTests {
+    @Mock
+    private lateinit var bookmarksPagerAdapter: BookmarksPagerAdapter
+
+    @Mock
+    private lateinit var fragmentManager: FragmentManager
+
+    @Mock
+    private lateinit var context: Context
+
+    @Before
+    fun setUp() {
+        MockitoAnnotations.initMocks(this)
+        bookmarksPagerAdapter = BookmarksPagerAdapter(fragmentManager, context)
+    }
+
+    @Test
+    fun checkNotNull() {
+        Assert.assertNotNull(bookmarksPagerAdapter)
+    }
+
+    @Test
+    fun testGetItem() {
+        bookmarksPagerAdapter.getItem(0)
+        bookmarksPagerAdapter.getItem(1)
+    }
+
+    @Test
+    fun testGetCount() {
+        Assert.assertEquals(bookmarksPagerAdapter.count, 2)
+    }
+
+    @Test
+    fun testGetPageTitle() {
+        bookmarksPagerAdapter.getPageTitle(0)
+    }
+}