Updated test cases to accommodate the new search functionality.

* Due to linking errors with libkiwix/libzim functions, direct usage in testing was not possible. To address this, helper classes were created, similar to those in `java-libkiwix`, for testing the search functionality.

core/src/test/java/org/kiwix/kiwixmobile/core/search/viewmodel/EntryWrapper.kt

@@ -0,0 +1,25 @@
+/*
+ * Kiwix Android
+ * Copyright (c) 2023 Kiwix <android.kiwix.org>
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+package org.kiwix.kiwixmobile.core.search.viewmodel
+
+import org.kiwix.libzim.Entry
+
+internal class EntryWrapper : Entry() {
+  override fun getTitle(): String = super.getTitle()
+}

core/src/test/java/org/kiwix/kiwixmobile/core/search/viewmodel/SearchIteratorWrapper.kt

@@ -0,0 +1,29 @@
+/*
+ * Kiwix Android
+ * Copyright (c) 2023 Kiwix <android.kiwix.org>
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+package org.kiwix.kiwixmobile.core.search.viewmodel
+
+import org.kiwix.libzim.SearchIterator
+
+// Create this as a helper class, as we can not directly use libkiwix/libzim functions in testing
+internal class SearchIteratorWrapper : SearchIterator() {
+  override fun remove() {}
+
+  override fun hasNext(): Boolean = super.hasNext()
+  override fun next(): EntryWrapper = super.next() as EntryWrapper
+}

core/src/test/java/org/kiwix/kiwixmobile/core/search/viewmodel/SearchStateTest.kt

@@ -18,25 +18,43 @@
 
 package org.kiwix.kiwixmobile.core.search.viewmodel
 
+import io.mockk.every
+import io.mockk.mockk
 import org.assertj.core.api.Assertions.assertThat
 import org.junit.jupiter.api.Test
 import org.kiwix.kiwixmobile.core.search.adapter.SearchListItem.RecentSearchListItem
-import org.kiwix.kiwixmobile.core.search.adapter.SearchListItem.ZimSearchResultListItem
 import org.kiwix.kiwixmobile.core.search.viewmodel.SearchOrigin.FromWebView
 
 internal class SearchStateTest {
 
   @Test
   internal fun `visibleResults use searchResults when searchTerm is not empty`() {
-    val results = listOf(ZimSearchResultListItem(""))
+    val searchTerm = "notEmpty"
+    val searchWrapper: SearchWrapper = mockk()
+    val searchIteratorWrapper: SearchIteratorWrapper = mockk()
+    val entryWrapper: EntryWrapper = mockk()
+    val estimatedMatches = 1
+    every { searchWrapper.estimatedMatches } returns estimatedMatches.toLong()
+    // Settings list to hasNext() to ensure it returns true only for the first call.
+    // Otherwise, if we do not set this, the method will always return true when checking if the iterator has a next value,
+    // causing our test case to get stuck in an infinite loop due to this explicit setting.
+    every { searchIteratorWrapper.hasNext() } returnsMany listOf(true, false)
+    every { searchIteratorWrapper.next() } returns entryWrapper
+    every { entryWrapper.title } returns searchTerm
+    every {
+      searchWrapper.getResults(
+        0,
+        estimatedMatches
+      )
+    } returns searchIteratorWrapper
     assertThat(
       SearchState(
-        "notEmpty",
-        SearchResultsWithTerm("", results),
+        searchTerm,
+        SearchResultsWithTerm("", searchWrapper),
         emptyList(),
         FromWebView
       ).getVisibleResults(0)
-    ).isEqualTo(results)
+    ).isEqualTo(listOf(RecentSearchListItem(searchTerm)))
   }
 
   @Test
@@ -45,7 +63,7 @@ internal class SearchStateTest {
     assertThat(
       SearchState(
         "",
-        SearchResultsWithTerm("", emptyList()),
+        SearchResultsWithTerm("", null),
         results,
         FromWebView
       ).getVisibleResults(0)
@@ -57,11 +75,11 @@ internal class SearchStateTest {
     assertThat(
       SearchState(
         "",
-        SearchResultsWithTerm("notEqual", emptyList()),
+        SearchResultsWithTerm("notEqual", null),
         emptyList(),
         FromWebView
       ).isLoading
-    ).isTrue()
+    ).isTrue
   }
 
   @Test
@@ -70,10 +88,10 @@ internal class SearchStateTest {
     assertThat(
       SearchState(
         searchTerm,
-        SearchResultsWithTerm(searchTerm, emptyList()),
+        SearchResultsWithTerm(searchTerm, null),
         emptyList(),
         FromWebView
       ).isLoading
-    ).isFalse()
+    ).isFalse
   }
 }

core/src/test/java/org/kiwix/kiwixmobile/core/search/viewmodel/SearchViewModelTest.kt

@@ -74,6 +74,7 @@ import org.kiwix.kiwixmobile.core.search.viewmodel.effects.SearchInPreviousScree
 import org.kiwix.kiwixmobile.core.search.viewmodel.effects.ShowDeleteSearchDialog
 import org.kiwix.kiwixmobile.core.search.viewmodel.effects.ShowToast
 import org.kiwix.kiwixmobile.core.search.viewmodel.effects.StartSpeechInput
+import org.kiwix.libzim.Search
 
 @OptIn(ExperimentalCoroutinesApi::class)
 internal class SearchViewModelTest {
@@ -101,7 +102,7 @@ internal class SearchViewModelTest {
     every { zimReaderContainer.copyReader() } returns zimFileReader
     coEvery {
       searchResultGenerator.generateSearchResults("", zimFileReader)
-    } returns emptyList()
+    } returns null
     every { zimReaderContainer.id } returns "id"
     every { recentSearchDao.recentSearches("id") } returns recentsFromDb.consumeAsFlow()
     viewModel = SearchViewModel(recentSearchDao, zimReaderContainer, searchResultGenerator)
@@ -112,7 +113,7 @@ internal class SearchViewModelTest {
     @Test
     fun `initial state is Initialising`() = runBlockingTest {
       viewModel.state.test(this).assertValue(
-        SearchState("", SearchResultsWithTerm("", emptyList()), emptyList(), FromWebView)
+        SearchState("", SearchResultsWithTerm("", null), emptyList(), FromWebView)
       ).finish()
     }
 
@@ -121,11 +122,12 @@ internal class SearchViewModelTest {
       val item = ZimSearchResultListItem("")
       val searchTerm = "searchTerm"
       val searchOrigin = FromWebView
+      val search: Search = mockk()
       viewModel.state.test(this)
         .also {
           emissionOf(
             searchTerm = searchTerm,
-            searchResults = listOf(item),
+            search = search,
             databaseResults = listOf(RecentSearchListItem("")),
             searchOrigin = searchOrigin
           )
@@ -133,7 +135,7 @@ internal class SearchViewModelTest {
         .assertValue(
           SearchState(
             searchTerm,
-            SearchResultsWithTerm(searchTerm, listOf(item)),
+            SearchResultsWithTerm(searchTerm, search),
             listOf(RecentSearchListItem("")),
             searchOrigin
           )
@@ -241,14 +243,14 @@ internal class SearchViewModelTest {
 
   private fun TestScope.emissionOf(
     searchTerm: String,
-    searchResults: List<ZimSearchResultListItem>,
+    search: Search,
     databaseResults: List<RecentSearchListItem>,
     searchOrigin: SearchOrigin
   ) {
 
     coEvery {
       searchResultGenerator.generateSearchResults(searchTerm, zimFileReader)
-    } returns searchResults
+    } returns search
     viewModel.actions.trySend(Filter(searchTerm)).isSuccess
     recentsFromDb.trySend(databaseResults).isSuccess
     viewModel.actions.trySend(ScreenWasStartedFrom(searchOrigin)).isSuccess

core/src/test/java/org/kiwix/kiwixmobile/core/search/viewmodel/SearchWrapper.kt

@@ -0,0 +1,29 @@
+/*
+ * Kiwix Android
+ * Copyright (c) 2023 Kiwix <android.kiwix.org>
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+package org.kiwix.kiwixmobile.core.search.viewmodel
+
+import org.kiwix.libzim.Search
+
+// Create this as a helper class, as we can not directly use libkiwix/libzim functions in testing
+internal class SearchWrapper : Search() {
+  override fun getEstimatedMatches(): Long = super.getEstimatedMatches()
+
+  override fun getResults(start: Int, maxResults: Int): SearchIteratorWrapper =
+    super.getResults(start, maxResults) as SearchIteratorWrapper
+}

core/src/test/java/org/kiwix/kiwixmobile/core/search/viewmodel/ZimSearchResultGeneratorTest.kt

@@ -25,8 +25,6 @@ import kotlinx.coroutines.runBlocking
 import org.assertj.core.api.Assertions.assertThat
 import org.junit.jupiter.api.Test
 import org.kiwix.kiwixmobile.core.reader.ZimFileReader
-import org.kiwix.kiwixmobile.core.search.adapter.SearchListItem.ZimSearchResultListItem
-import org.kiwix.libzim.Search
 
 internal class ZimSearchResultGeneratorTest {
 
@@ -39,21 +37,18 @@ internal class ZimSearchResultGeneratorTest {
   internal fun `empty search term returns empty list`() {
     runBlocking {
       assertThat(zimSearchResultGenerator.generateSearchResults("", zimFileReader))
-        .isEqualTo(emptyList<ZimSearchResultListItem>())
+        .isEqualTo(null)
     }
   }
 
   @Test
   internal fun `suggestion results are distinct`() {
-    val validTitle = "title"
     val searchTerm = " "
-    val item = ZimSearchResultListItem(validTitle)
-    val search: Search = mockk()
-    every { zimFileReader.searchSuggestions(searchTerm) } returns search
-    every { zimFileReader.getSearchResultList(search) } returns listOf(item)
+    val searchWrapper: SearchWrapper = mockk()
+    every { zimFileReader.searchSuggestions(searchTerm) } returns searchWrapper
     runBlocking {
       assertThat(zimSearchResultGenerator.generateSearchResults(searchTerm, zimFileReader))
-        .isEqualTo(listOf(ZimSearchResultListItem(validTitle)))
+        .isEqualTo(searchWrapper)
       verify {
         zimFileReader.searchSuggestions(searchTerm)
       }