Fixed crash in recycler view due to duplicate stable ids in download home

Sometimes we incorrectly create two Just Now sections in download home.
This leads to a crash in RecyclerView as stable IDs should be unique.
This happens especially when there are two downloads very close to midnight,
one before midnight and one after midnight. This CL fixes this issue
and places both of them in one Just Now section.

Change-Id: I5af6560c29a7413f86a6245719859197d72268dd
Bug: 1020079
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2024068Reviewed-by: David Trainor <dtrainor@chromium.org>
Commit-Queue: Shakti Sahu <shaktisahu@chromium.org>
Cr-Commit-Position: refs/heads/master@{#735708}

chrome/android/java/src/org/chromium/chrome/browser/download/home/JustNowProvider.java

@@ -4,6 +4,8 @@
 
 package org.chromium.chrome.browser.download.home;
 
+import androidx.annotation.VisibleForTesting;
+
 import org.chromium.components.offline_items_collection.ContentId;
 import org.chromium.components.offline_items_collection.OfflineItem;
 import org.chromium.components.offline_items_collection.OfflineItemState;
@@ -24,7 +26,7 @@ public class JustNowProvider {
 
     /** Constructor. */
     public JustNowProvider(DownloadManagerUiConfig config) {
-        mThresholdDate = new Date(new Date().getTime() - config.justNowThresholdSeconds * 1000);
+        mThresholdDate = new Date(now().getTime() - config.justNowThresholdSeconds * 1000);
     }
 
     /**
@@ -41,4 +43,9 @@ public class JustNowProvider {
                 || (item.state == OfflineItemState.INTERRUPTED && item.isResumable)
                 || new Date(item.completionTimeMs).after(mThresholdDate);
     }
-}
+
+    @VisibleForTesting
+    protected Date now() {
+        return new Date();
+    }
+}
\ No newline at end of file

chrome/android/java/src/org/chromium/chrome/browser/download/home/list/mutator/DateLabelAdder.java

@@ -54,8 +54,11 @@ public class DateLabelAdder implements ListConsumer {
             if (!(listItem instanceof OfflineItemListItem)) continue;
 
             OfflineItem offlineItem = ((OfflineItemListItem) listItem).item;
-            if (startOfNewDay(offlineItem, previousItem)
-                    || justNowSectionsDiffer(offlineItem, previousItem)) {
+            boolean startOfNewDay = startOfNewDay(offlineItem, previousItem);
+            boolean isJustNow =
+                    mJustNowProvider != null && mJustNowProvider.isJustNowItem(offlineItem);
+            if (isJustNow) startOfNewDay = false;
+            if (startOfNewDay || justNowSectionsDiffer(offlineItem, previousItem)) {
                 addDateHeader(listItems, offlineItem, i);
             }
 

chrome/android/junit/src/org/chromium/chrome/browser/download/home/list/DateOrderedListMutatorTest.java

@@ -145,7 +145,7 @@ public class DateOrderedListMutatorTest {
         DateOrderedListMutator list = createMutatorWithJustNowProvider();
 
         Assert.assertEquals(2, mModel.size());
-        assertJustNowSection(mModel.get(0), false);
+        assertJustNowSection(mModel.get(0));
         assertOfflineItem(mModel.get(1), buildCalendar(2018, 1, 1, 1), item1);
     }
 
@@ -159,20 +159,56 @@ public class DateOrderedListMutatorTest {
      */
     @Test
     public void testMultipleSectionsInJustNowSection() {
-        OfflineItem item1 = buildItem("1", buildCalendar(2018, 1, 1, 1), OfflineItemFilter.VIDEO);
-        OfflineItem item2 = buildItem("2", buildCalendar(2018, 1, 1, 1), OfflineItemFilter.AUDIO);
+        Calendar calendar = buildCalendar(2018, 1, 1, 1);
+        OfflineItem item1 = buildItem("1", calendar, OfflineItemFilter.VIDEO);
+        OfflineItem item2 = buildItem("2", calendar, OfflineItemFilter.AUDIO);
         item1.state = OfflineItemState.IN_PROGRESS;
-        item2.state = OfflineItemState.IN_PROGRESS;
+        item2.state = OfflineItemState.COMPLETE;
         item2.completionTimeMs = item2.creationTimeMs;
         when(mSource.getItems()).thenReturn(CollectionUtil.newArrayList(item1, item2));
-        DateOrderedListMutator list = createMutatorWithJustNowProvider();
+        DateOrderedListMutator list =
+                createMutatorWithJustNowProvider(buildJustNowProvider(calendar.getTime()));
 
         Assert.assertEquals(3, mModel.size());
-        assertJustNowSection(mModel.get(0), false);
+        assertJustNowSection(mModel.get(0));
         assertOfflineItem(mModel.get(1), buildCalendar(2018, 1, 1, 1), item1);
         assertOfflineItem(mModel.get(2), buildCalendar(2018, 1, 1, 1), item2);
     }
 
+    /**
+     * Action                               List
+     * 1. Set(item1 @ 0:10 1/2/2018         [ DATE    Just Now,
+     *              Video COMPLETE,
+     *        item2 @ 23:55 1/1/2018         [ DATE    Just Now,
+     *              Video COMPLETE,
+     *
+     *        item3 @ 10:00 1/1/2018           DATE    1/1/2018
+     *              Audio COMPLETE)           item3   @ 1:00 1/1/2018 ]
+     */
+    @Test
+    public void testRecentItemBeforeMidnightShowsInJustNowSection() {
+        Calendar calendar1 = CalendarFactory.get();
+        calendar1.set(2018, 1, 2, 0, 10);
+        Calendar calendar2 = CalendarFactory.get();
+        calendar2.set(2018, 1, 1, 23, 50);
+        OfflineItem item1 = buildItem("1", calendar1, OfflineItemFilter.VIDEO);
+        OfflineItem item2 = buildItem("2", calendar2, OfflineItemFilter.AUDIO);
+        OfflineItem item3 = buildItem("3", buildCalendar(2018, 1, 1, 10), OfflineItemFilter.AUDIO);
+        item1.completionTimeMs = item1.creationTimeMs;
+        item2.completionTimeMs = item2.creationTimeMs;
+        when(mSource.getItems()).thenReturn(CollectionUtil.newArrayList(item1, item2, item3));
+
+        Calendar now = CalendarFactory.get();
+        now.set(2018, 1, 2, 0, 15);
+        createMutatorWithJustNowProvider(buildJustNowProvider(now.getTime()));
+        Assert.assertEquals(5, mModel.size());
+        assertJustNowSection(mModel.get(0));
+        assertOfflineItem(mModel.get(1), calendar1, item1);
+        assertOfflineItem(mModel.get(2), calendar2, item2);
+        assertSectionHeader(mModel.get(3), buildCalendar(2018, 1, 1, 0), true);
+        assertOfflineItem(mModel.get(4), buildCalendar(2018, 1, 1, 10), item3);
+    }
+
     /**
      * Action                               List
      * 1. Set(item1 @ 1:00 1/1/2018         [ DATE    Just Now,
@@ -197,7 +233,7 @@ public class DateOrderedListMutatorTest {
         mModel.addObserver(mObserver);
 
         Assert.assertEquals(2, mModel.size());
-        assertJustNowSection(mModel.get(0), false);
+        assertJustNowSection(mModel.get(0));
         assertOfflineItem(mModel.get(1), buildCalendar(2018, 1, 1, 1), item1);
 
         // Resume the download.
@@ -207,7 +243,7 @@ public class DateOrderedListMutatorTest {
         list.onItemUpdated(item1, update1);
 
         Assert.assertEquals(2, mModel.size());
-        assertJustNowSection(mModel.get(0), false);
+        assertJustNowSection(mModel.get(0));
         assertOfflineItem(mModel.get(1), buildCalendar(2018, 1, 1, 1), update1);
 
         // Complete the download.
@@ -218,7 +254,7 @@ public class DateOrderedListMutatorTest {
         list.onItemUpdated(update1, update2);
 
         Assert.assertEquals(2, mModel.size());
-        assertJustNowSection(mModel.get(0), false);
+        assertJustNowSection(mModel.get(0));
         assertOfflineItem(mModel.get(1), buildCalendar(2018, 1, 1, 1), update2);
 
         // Too much time has passed since completion of the download.
@@ -229,7 +265,7 @@ public class DateOrderedListMutatorTest {
         list.onItemUpdated(update2, update3);
 
         Assert.assertEquals(2, mModel.size());
-        assertJustNowSection(mModel.get(0), false);
+        assertJustNowSection(mModel.get(0));
         assertOfflineItem(mModel.get(1), buildCalendar(2018, 1, 1, 1), update3);
     }
 
@@ -250,7 +286,7 @@ public class DateOrderedListMutatorTest {
         DateOrderedListMutator list = createMutatorWithJustNowProvider();
 
         Assert.assertEquals(4, mModel.size());
-        assertJustNowSection(mModel.get(0), false);
+        assertJustNowSection(mModel.get(0));
         assertOfflineItem(mModel.get(1), buildCalendar(2018, 2, 1, 1), item1);
         assertSectionHeader(mModel.get(2), buildCalendar(2018, 1, 1, 0), true);
         assertOfflineItem(mModel.get(3), buildCalendar(2018, 1, 1, 1), item2);
@@ -871,11 +907,25 @@ public class DateOrderedListMutatorTest {
         return item;
     }
 
+    private DownloadManagerUiConfig createConfig() {
+        return new DownloadManagerUiConfig.Builder()
+                .setUseNewDownloadPath(true)
+                .setSupportsGrouping(false)
+                .build();
+    }
+
+    private JustNowProvider buildJustNowProvider(Date overrideNow) {
+        JustNowProvider justNowProvider = new JustNowProvider(createConfig()) {
+            @Override
+            protected Date now() {
+                return overrideNow;
+            }
+        };
+        return justNowProvider;
+    }
+
     private DateOrderedListMutator createMutatorWithoutJustNowProvider() {
-        DownloadManagerUiConfig config = new DownloadManagerUiConfig.Builder()
-                                                 .setUseNewDownloadPath(true)
-                                                 .setSupportsGrouping(false)
-                                                 .build();
+        DownloadManagerUiConfig config = createConfig();
         JustNowProvider justNowProvider = new JustNowProvider(config) {
             @Override
             public boolean isJustNowItem(OfflineItem item) {
@@ -889,14 +939,15 @@ public class DateOrderedListMutatorTest {
     }
 
     private DateOrderedListMutator createMutatorWithJustNowProvider() {
-        DownloadManagerUiConfig config = new DownloadManagerUiConfig.Builder()
-                                                 .setUseNewDownloadPath(true)
-                                                 .setSupportsGrouping(false)
-                                                 .build();
-        JustNowProvider justNowProvider = new JustNowProvider(config);
+        JustNowProvider justNowProvider = new JustNowProvider(createConfig());
+        return createMutatorWithJustNowProvider(justNowProvider);
+    }
+
+    private DateOrderedListMutator createMutatorWithJustNowProvider(
+            JustNowProvider justNowProvider) {
         DateOrderedListMutator mutator =
                 new DateOrderedListMutator(mSource, mModel, justNowProvider);
-        new ListMutationController(config, justNowProvider, mutator, mModel);
+        new ListMutationController(createConfig(), justNowProvider, mutator, mModel);
         return mutator;
     }
 
@@ -923,11 +974,11 @@ public class DateOrderedListMutatorTest {
         Assert.assertEquals(sectionHeader.showTopDivider, showDivider);
     }
 
-    private static void assertJustNowSection(ListItem item, boolean showDivider) {
+    private static void assertJustNowSection(ListItem item) {
         Assert.assertTrue(item instanceof SectionHeaderListItem);
         SectionHeaderListItem sectionHeader = (SectionHeaderListItem) item;
         Assert.assertTrue(sectionHeader.isJustNow);
-        Assert.assertEquals(sectionHeader.showTopDivider, showDivider);
+        Assert.assertEquals(false, sectionHeader.showTopDivider);
         Assert.assertEquals(StableIds.JUST_NOW_SECTION, item.stableId);
     }
 }