NTP cards: Restructure change notifications.

chrome/android/junit/src/org/chromium/chrome/browser/ntp/cards/SuggestionsSectionTest.java

Index: chrome/android/junit/src/org/chromium/chrome/browser/ntp/cards/SuggestionsSectionTest.java
diff --git a/chrome/android/junit/src/org/chromium/chrome/browser/ntp/cards/SuggestionsSectionTest.java b/chrome/android/junit/src/org/chromium/chrome/browser/ntp/cards/SuggestionsSectionTest.java
index b79c074da4c22c6cf53316eb30650d3b43516bc2..c8f05d141f8d64f7599cd9dab6fd2b726c8b6b60 100644
--- a/chrome/android/junit/src/org/chromium/chrome/browser/ntp/cards/SuggestionsSectionTest.java
+++ b/chrome/android/junit/src/org/chromium/chrome/browser/ntp/cards/SuggestionsSectionTest.java
@@ -9,17 +9,18 @@ import static org.junit.Assert.assertNotNull;
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.ArgumentMatchers.anyInt;
 import static org.mockito.ArgumentMatchers.eq;
-import static org.mockito.Mockito.mock;
 import static org.mockito.Mockito.never;
 import static org.mockito.Mockito.times;
 import static org.mockito.Mockito.verify;
 
+import org.junit.Before;
 import org.junit.Test;
 import org.junit.runner.RunWith;
+import org.mockito.Mock;
+import org.mockito.MockitoAnnotations;
 import org.robolectric.annotation.Config;
 
 import static org.chromium.chrome.browser.ntp.cards.ContentSuggestionsTestUtils.createDummySuggestions;
-import static org.chromium.chrome.browser.ntp.cards.ContentSuggestionsTestUtils.createInfo;
 import static org.chromium.chrome.browser.ntp.cards.ContentSuggestionsTestUtils.createSection;
 
 import org.chromium.base.test.util.Feature;
@@ -40,14 +41,21 @@ public class SuggestionsSectionTest {
      */
     private static final int EMPTY_SECTION_COUNT = 4;
 
+    @Mock
+    private ItemGroup.Observer mObserver;
+
+    @Before
+    public void setUp() {
+        MockitoAnnotations.initMocks(this);
+    }
+
     @Test
     @Feature({"Ntp"})
     public void testDismissSibling() {
-        ItemGroup.Observer observerMock = mock(ItemGroup.Observer.class);
         List<SnippetArticle> snippets = createDummySuggestions(3);
         SuggestionsSection section;
 
-        section = new SuggestionsSection(createInfo(42, true, true), observerMock);
+        section = ContentSuggestionsTestUtils.createSection(true, true, mObserver);
         section.setStatus(CategoryStatus.AVAILABLE);
         assertNotNull(section.getActionItem());
 
@@ -65,95 +73,97 @@ public class SuggestionsSectionTest {
     @Test
     @Feature({"Ntp"})
     public void testSetSuggestionsNotification() {
-        ItemGroup.Observer observerMock = mock(ItemGroup.Observer.class);
-
         final int suggestionCount = 5;
         List<SnippetArticle> snippets = createDummySuggestions(suggestionCount);
 
-        SuggestionsSection section = createSection(false, true, observerMock);
+        SuggestionsSection section = createSection(false, true, mObserver);
         // Note: when status is not initialised, we insert an item for the status card, but it's
         // null!
         assertEquals(EMPTY_SECTION_COUNT, section.getItems().size());
 
         section.setSuggestions(snippets, CategoryStatus.AVAILABLE);
-        verify(observerMock)
-                .notifyGroupChanged(
-                        eq(section), eq(EMPTY_SECTION_COUNT), eq(suggestionCount + 1 /* header */));
+        verify(mObserver).onItemRangeChanged(section, 1, EMPTY_SECTION_COUNT - 1);
+        verify(mObserver).onItemRangeInserted(
+                section, EMPTY_SECTION_COUNT, suggestionCount - EMPTY_SECTION_COUNT + 1);
     }
 
     @Test
     @Feature({"Ntp"})
     public void testSetStatusNotification() {
-        ItemGroup.Observer observerMock = mock(ItemGroup.Observer.class);
         final int suggestionCount = 5;
         List<SnippetArticle> snippets = createDummySuggestions(suggestionCount);
 
-        SuggestionsSection section = createSection(false, true, observerMock);
+        SuggestionsSection section = createSection(false, true, mObserver);
 
         section.setStatus(CategoryStatus.AVAILABLE);
-        verify(observerMock)
-                .notifyGroupChanged(eq(section), eq(EMPTY_SECTION_COUNT), eq(EMPTY_SECTION_COUNT));
+        verify(mObserver).onItemRangeChanged(section, 1, EMPTY_SECTION_COUNT - 1);
 
         section.setSuggestions(snippets, CategoryStatus.AVAILABLE);
 
         // We don't clear suggestions when the status is AVAILABLE.
         section.setStatus(CategoryStatus.AVAILABLE);
-        verify(observerMock)
-                .notifyGroupChanged(eq(section), eq(suggestionCount + 1), eq(suggestionCount + 1));
+        verify(mObserver, times(2)).onItemRangeChanged(section, 1, EMPTY_SECTION_COUNT - 1);
+        verify(mObserver).onItemRangeInserted(
+                section, EMPTY_SECTION_COUNT, suggestionCount - EMPTY_SECTION_COUNT + 1);
 
         // We clear existing suggestions when the status is not AVAILABLE.
-        section.setStatus(CategoryStatus.LOADING_ERROR);
-        verify(observerMock)
-                .notifyGroupChanged(eq(section), eq(suggestionCount + 1), eq(EMPTY_SECTION_COUNT));
+        section.setStatus(CategoryStatus.SIGNED_OUT);
+        verify(mObserver, times(3)).onItemRangeChanged(section, 1, EMPTY_SECTION_COUNT - 1);
+        verify(mObserver).onItemRangeRemoved(
+                section, EMPTY_SECTION_COUNT, suggestionCount - EMPTY_SECTION_COUNT + 1);
     }
 
     @Test
     @Feature({"Ntp"})
     public void testRemoveSuggestionNotification() {
-        ItemGroup.Observer observerMock = mock(ItemGroup.Observer.class);
-
         final int suggestionCount = 2;
         List<SnippetArticle> snippets = createDummySuggestions(suggestionCount);
 
-        SuggestionsSection section = createSection(false, true, observerMock);
+        SuggestionsSection section = createSection(false, true, mObserver);
 
         section.removeSuggestion(snippets.get(0));
-        verify(observerMock, never()).notifyGroupChanged(any(ItemGroup.class), anyInt(), anyInt());
-        verify(observerMock, never()).notifyItemRemoved(any(ItemGroup.class), anyInt());
+        verify(mObserver, never())
+                .onItemRangeChanged(any(SuggestionsSection.class), anyInt(), anyInt());
+        verify(mObserver, never())
+                .onItemRangeInserted(any(SuggestionsSection.class), anyInt(), anyInt());
+        verify(mObserver, never())
+                .onItemRangeRemoved(any(SuggestionsSection.class), anyInt(), anyInt());
 
         section.setSuggestions(snippets, CategoryStatus.AVAILABLE);
 
         section.removeSuggestion(snippets.get(1));
-        verify(observerMock).notifyItemRemoved(section, 2);
+        verify(mObserver).onItemRangeRemoved(eq(section), eq(2), eq(1));
 
         section.removeSuggestion(snippets.get(0));
-        verify(observerMock).notifyItemRemoved(section, 1);
-        verify(observerMock).notifyItemInserted(section, 1);
-        verify(observerMock).notifyItemInserted(section, 2);
+        verify(mObserver).onItemRangeRemoved(eq(section), eq(1), eq(1));
+        verify(mObserver).onItemRangeInserted(eq(section), eq(1), eq(1));
+        verify(mObserver).onItemRangeInserted(eq(section), eq(2), eq(1));
     }
 
     @Test
     @Feature({"Ntp"})
     public void testRemoveSuggestionNotificationWithButton() {
-        ItemGroup.Observer observerMock = mock(ItemGroup.Observer.class);
-
         final int suggestionCount = 2;
         List<SnippetArticle> snippets = createDummySuggestions(suggestionCount);
 
-        SuggestionsSection section = createSection(true, true, observerMock);
+        SuggestionsSection section = createSection(true, true, mObserver);
 
         section.removeSuggestion(snippets.get(0));
-        verify(observerMock, never()).notifyGroupChanged(any(ItemGroup.class), anyInt(), anyInt());
-        verify(observerMock, never()).notifyItemRemoved(any(ItemGroup.class), anyInt());
+        verify(mObserver, never())
+                .onItemRangeChanged(any(SuggestionsSection.class), anyInt(), anyInt());
+        verify(mObserver, never())
+                .onItemRangeInserted(any(SuggestionsSection.class), anyInt(), anyInt());
+        verify(mObserver, never())
+                .onItemRangeRemoved(any(SuggestionsSection.class), anyInt(), anyInt());
 
         section.setSuggestions(snippets, CategoryStatus.AVAILABLE);
 
         section.removeSuggestion(snippets.get(0));
-        verify(observerMock).notifyItemRemoved(section, 1);
+        verify(mObserver).onItemRangeRemoved(eq(section), eq(1), eq(1));
 
         section.removeSuggestion(snippets.get(1));
-        verify(observerMock, times(2)).notifyItemRemoved(section, 1);
-        verify(observerMock).notifyItemInserted(section, 1);
-        verify(observerMock).notifyItemInserted(section, 3);
+        verify(mObserver, times(2)).onItemRangeRemoved(eq(section), eq(1), eq(1));
+        verify(mObserver).onItemRangeInserted(eq(section), eq(1), eq(1));
+        verify(mObserver).onItemRangeInserted(eq(section), eq(3), eq(1));
     }
 }