Fix search trigger bug when deleting and adding again the same issue.

Found during #239.

CHANGES.rst

@@ -26,6 +26,10 @@ Unreleased
 * Fix bug causing
   :attr:`~Entry.read_modified` and :attr:`~Entry.important_modified`
   to be reset to :const:`None` when an entry is updated.
+* Fix bug where deleting an entry and then adding it again
+  (with the same id) would fail
+  if search was enabled and :meth:`~Reader.update_search`
+  was not run before adding the new entry.
 
 
 Version 2.4

src/reader/_search.py

@@ -303,26 +303,47 @@ def _create_triggers(self) -> None:
         # the ON DELETE trigger doesn't fire during REPLACE
         # if recursive_triggers are not enabled (they aren't, as of 1.5).
         #
-        # What I don't understand is why the "INSERT into esss" below succeeds
-        # even when a specific (id, feed) already exists in esss
-        # (it seems to act as INSERT OR REPLACE -- maybe because it already
-        # is in one, and that REPLACE is global?).
-        # Anyway, it seems to do what we need it to do.
+        # Note the entries_search_entries_insert{,_esss_exists} trigers
+        # cannot use OR REPLACE, so we must have one trigger for each case.
 
         self.db.execute(
             """
             CREATE TRIGGER entries_search_entries_insert
             AFTER INSERT ON entries
+
+            WHEN
+                NOT EXISTS (
+                    SELECT *
+                    FROM entries_search_sync_state AS esss
+                    WHERE (esss.id, esss.feed) = (new.id, new.feed)
+                )
+
             BEGIN
-                INSERT OR REPLACE INTO entries_search_sync_state (id, feed, es_rowids)
-                VALUES (
-                    new.id,
-                    new.feed,
-                    coalesce((
-                        SELECT es_rowids
-                        from entries_search_sync_state
-                        where (id, feed) = (new.id, new.feed)
-                    ), '[]')
+                INSERT INTO entries_search_sync_state (id, feed)
+                VALUES (new.id, new.feed);
+            END;
+            """
+        )
+        self.db.execute(
+            """
+            CREATE TRIGGER entries_search_entries_insert_esss_exists
+            AFTER INSERT ON entries
+
+            WHEN
+                EXISTS (
+                    SELECT *
+                    FROM entries_search_sync_state AS esss
+                    WHERE (esss.id, esss.feed) = (new.id, new.feed)
+                )
+
+            BEGIN
+                UPDATE entries_search_sync_state
+                SET
+                    to_update = 1,
+                    to_delete = 0
+                WHERE (new.id, new.feed) = (
+                    entries_search_sync_state.id,
+                    entries_search_sync_state.feed
                 );
             END;
             """
@@ -446,6 +467,9 @@ def _drop_triggers(self) -> None:
         # Private API, may be called from migrations.
         assert self.db.in_transaction
         self.db.execute("DROP TRIGGER IF EXISTS entries_search_entries_insert;")
+        self.db.execute(
+            "DROP TRIGGER IF EXISTS entries_search_entries_insert_esss_exists;"
+        )
         self.db.execute("DROP TRIGGER IF EXISTS entries_search_entries_update;")
         self.db.execute("DROP TRIGGER IF EXISTS entries_search_entries_delete;")
         self.db.execute("DROP TRIGGER IF EXISTS entries_search_feeds_update;")

src/reader/_storage.py

@@ -1013,7 +1013,7 @@ def make_params() -> Iterable[Mapping[str, Any]]:
                 if "foreign key constraint failed" in e_msg:
                     raise FeedNotFoundError(feed_url) from None
 
-                elif "unique constraint failed" in e_msg:
+                elif "unique constraint failed: entries.id, entries.feed" in e_msg:
                     raise EntryExistsError(feed_url, entry_id) from None
 
                 else:  # pragma: no cover

tests/test_reader_search.py

@@ -1069,3 +1069,19 @@ def strip_html(*args, **kwargs):
 
 
 # END concurrency tests
+
+
+def test_add_entry_repeatedly(reader):
+    # this could have been found with Hypothesis
+
+    reader.enable_search()
+    reader.add_feed('1')
+
+    # we should not get
+    #   sqlite3.IntegrityError: UNIQUE constraint failed:
+    #     entries_search_sync_state.id, entries_search_sync_state.feed
+    # on the second loop
+
+    for _ in range(3):
+        reader.add_entry(dict(feed_url='1', id='1'))
+        reader.delete_entry(('1', '1'))