Feeds: Fixed handlig of duplicate entries

Feed entries are expected to have unique URLs, since the URL is the identifier of an entry. If a feed has the same URL for more than one entry, only process the first one and ignore the rest.

An entry will still show up as unread if it keeps the same URL but changes its title.

2 files changed, 12 insertions, 0 deletions

diff --git a/res/about/version.gmi b/res/about/version.gmi
index a5e0d01f..6b2e9a45 100644
--- a/res/about/version.gmi
+++ b/res/about/version.gmi
@@ -13,9 +13,11 @@ New features:
 * Windows: Automatic updates using the WinSparkle library.
 
 Changes and enhancements:
+* Navigating back and forward in history will skip input query prompts (status 1x), showing only the query results. 
 * The resource bundle (resources.lgr) is now a regular ZIP archive. This allows it to do double duty as a fontpack containing the built-in fonts. The archive contains a version number to avoid use of obsolete resources.
 
 Fixes:
+* Handling duplicate feed entries: if multiple entries in a feed have the same URL, only handle the first one.
 
 ## 1.8.3
 * Fixed clicking on UI elements that are over the page top banner. The banner would always get clicked instead.
diff --git a/src/feeds.c b/src/feeds.c
index baec6870..26b3d6db 100644
--- a/src/feeds.c
+++ b/src/feeds.c
@@ -386,10 +386,18 @@ static iBool updateEntries_Feeds_(iFeeds *d, iBool isHeadings, uint32_t sourceId
                 setUrlKept_Visited(visited_App(), &entry->url, iTrue);
             }
         }
+        iStringSet *handledUrls = new_StringSet();
         lock_Mutex(d->mtx);
         iForEach(PtrArray, i, incoming) {
             iFeedEntry *entry = i.ptr;
             size_t pos;
+            if (contains_StringSet(handledUrls, &entry->url)) {
+                /* This is a duplicate. Each unique URL is handled only once. */
+                delete_FeedEntry(entry);
+                remove_PtrArrayIterator(&i);
+                continue;
+            }
+            insert_StringSet(handledUrls, &entry->url);
             if (locate_SortedArray(&d->entries, &entry, &pos)) {
                 iFeedEntry *existing = *(iFeedEntry **) at_SortedArray(&d->entries, pos);
                 iAssert(!isHeadingEntry_FeedEntry_(existing));
@@ -422,6 +430,8 @@ static iBool updateEntries_Feeds_(iFeeds *d, iBool isHeadings, uint32_t sourceId
             remove_PtrArrayIterator(&i);
         }
         unlock_Mutex(d->mtx);
+        fflush(stdout);
+        iRelease(handledUrls);
     }
     return gotNew;
 }