Empty search text is added in recent searches problem fix. (#1223)

* Add if state to prevent blank query.

* Create test emptySearchText_NotAddToRecentSearches
- For empty query not add in recent query list.

* Apply early return.

* assertEquals to assertNull.

Co-authored-by: Simon Marquis <contact@simon-marquis.fr>

* Import org.junit.Assert.assertNull

* Change org.junit.Assert.assertNull to kotlin.test.assertNull.

Change-Id: I60083b0b9a1dcaed84d957b49c91e5163d5659d6

* Add 'or' to prevent search when query is blank.

Change-Id: If498de05889d6d5946b1bbb1d1c10cb311bb9b52

* Create stateIsEmptyQuery_withThreeWhiteSpacesSearchQuery test.

Change-Id: I6d6e8f9fe988ca83fae484e4f2338ad6fe58b676

* Add UI logic to prevent blank text search in SearchScreen.
- Early return to do not call onSearchExplicitlyTriggered()

Change-Id: I28db284eac9059fb6f48dd718721a1fc5fdb8f7a

* Apply trim at query to remove whitespace.

Change-Id: Id349af4bb1af3d0f1c3973e6fb9e6f3e7b924d9b

* Create test stateIsEmptyQuery_withThreeWhiteSpacesAndOneLetterSearchQuery

Change-Id: Iee59f6085e4045b2e3c532f78804926290b6c6c5

* Update feature/search/src/test/kotlin/com/google/samples/apps/nowinandroid/feature/search/SearchViewModelTest.kt

Change name to emptySearchText_isNotAddedTorecentSearches()

Co-authored-by: Don Turner <dturner@users.noreply.github.com>

* Change name to searchTextWithThreeSpaces_isEmptyQuery()

Co-authored-by: Don Turner <dturner@users.noreply.github.com>

* Change name to searchTextWithThreeWhiteSpacesAndOneCharacter_isEmptyQuery()

Change-Id: I4c82b12e2c9bd4ff480e94061caf257a603e38da

* Revert "Change name to searchTextWithThreeWhiteSpacesAndOneCharacter_isEmptyQuery()"

This reverts commit e4c176598a.

* Change name to searchTextWithThreeSpacesAndOneLetter_isEmptyQuery

Co-authored-by: Don Turner <dturner@users.noreply.github.com>

* Add end curly bracket.

Change-Id: I7bd113e7b65d646f5321e34a7df2868f6e239cad

---------

Co-authored-by: Simon Marquis <contact@simon-marquis.fr>
Co-authored-by: Don Turner <dturner@users.noreply.github.com>

feature/search/src/main/kotlin/com/google/samples/apps/nowinandroid/feature/search/SearchScreen.kt

@@ -522,6 +522,7 @@ private fun SearchTextField(
             .focusRequester(focusRequester)
             .onKeyEvent {
                 if (it.key == Key.Enter) {
+                    if (searchQuery.isBlank()) return@onKeyEvent false
                     onSearchExplicitlyTriggered()
                     true
                 } else {
@@ -536,6 +537,7 @@ private fun SearchTextField(
         ),
         keyboardActions = KeyboardActions(
             onSearch = {
+                if (searchQuery.isBlank()) return@KeyboardActions
                 onSearchExplicitlyTriggered()
             },
         ),

feature/search/src/main/kotlin/com/google/samples/apps/nowinandroid/feature/search/SearchViewModel.kt

@@ -59,7 +59,7 @@ class SearchViewModel @Inject constructor(
                     flowOf(SearchResultUiState.SearchNotReady)
                 } else {
                     searchQuery.flatMapLatest { query ->
-                        if (query.length < SEARCH_QUERY_MIN_LENGTH) {
+                        if (query.trim().length < SEARCH_QUERY_MIN_LENGTH) {
                             flowOf(SearchResultUiState.EmptyQuery)
                         } else {
                             getSearchContentsUseCase(query)
@@ -102,6 +102,7 @@ class SearchViewModel @Inject constructor(
      * search query in the search text field, defining this method.
      */
     fun onSearchTriggered(query: String) {
+        if (query.isBlank()) return
         viewModelScope.launch {
             recentSearchRepository.insertOrReplaceRecentSearch(searchQuery = query)
         }

feature/search/src/test/kotlin/com/google/samples/apps/nowinandroid/feature/search/SearchViewModelTest.kt

@@ -41,6 +41,7 @@ import org.junit.Rule
 import org.junit.Test
 import kotlin.test.assertEquals
 import kotlin.test.assertIs
+import kotlin.test.assertNull
 
 /**
  * To learn more about how this test handles Flows created with stateIn, see
@@ -122,6 +123,43 @@ class SearchViewModelTest {
         assertEquals(SearchNotReady, viewModel.searchResultUiState.value)
     }
 
+    @Test
+    fun emptySearchText_isNotAddedToRecentSearches() = runTest {
+        viewModel.onSearchTriggered("")
+
+        val recentSearchQueriesStream = getRecentQueryUseCase()
+        val recentSearchQueries = recentSearchQueriesStream.first()
+        val recentSearchQuery = recentSearchQueries.firstOrNull()
+
+        assertNull(recentSearchQuery)
+    }
+
+    @Test
+    fun searchTextWithThreeSpaces_isEmptyQuery() = runTest {
+        searchContentsRepository.addNewsResources(newsResourcesTestData)
+        searchContentsRepository.addTopics(topicsTestData)
+        val collectJob = launch(UnconfinedTestDispatcher()) { viewModel.searchResultUiState.collect() }
+
+        viewModel.onSearchQueryChanged("   ")
+
+        assertIs<EmptyQuery>(viewModel.searchResultUiState.value)
+
+        collectJob.cancel()
+    }
+
+    @Test
+    fun searchTextWithThreeSpacesAndOneLetter_isEmptyQuery() = runTest {
+        searchContentsRepository.addNewsResources(newsResourcesTestData)
+        searchContentsRepository.addTopics(topicsTestData)
+        val collectJob = launch(UnconfinedTestDispatcher()) { viewModel.searchResultUiState.collect() }
+
+        viewModel.onSearchQueryChanged("   a")
+
+        assertIs<EmptyQuery>(viewModel.searchResultUiState.value)
+
+        collectJob.cancel()
+    }
+
     @Test
     fun whenToggleNewsResourceSavedIsCalled_bookmarkStateIsUpdated() = runTest {
         val newsResourceId = "123"