Fix assertion failure (#13626)

Co-authored-by: Carl Lin <carl@solana.com>

ledger/src/blockstore.rs

@@ -2490,7 +2490,8 @@ impl Blockstore {
             .collect();
 
         let data_shreds = data_shreds?;
-        assert!(data_shreds.last().unwrap().data_complete());
+        let last_shred = data_shreds.last().unwrap();
+        assert!(last_shred.data_complete() || last_shred.last_in_slot());
 
         let deshred_payload = Shredder::deshred(&data_shreds).map_err(|e| {
             BlockstoreError::InvalidShredData(Box::new(bincode::ErrorKind::Custom(format!(
@@ -7304,4 +7305,24 @@ pub mod tests {
         }
         Blockstore::destroy(&blockstore_path).expect("Expected successful database destruction");
     }
+
+    #[test]
+    fn test_remove_shred_data_complete_flag() {
+        let (mut shreds, entries) = make_slot_entries(0, 0, 1);
+
+        let ledger_path = get_tmp_ledger_path!();
+        let ledger = Blockstore::open(&ledger_path).unwrap();
+
+        // Remove the data complete flag from the last shred
+        shreds[0].unset_data_complete();
+
+        ledger.insert_shreds(shreds, None, false).unwrap();
+
+        // Check that the `data_complete` flag was unset in the stored shred, but the
+        // `last_in_slot` flag is set.
+        let stored_shred = &ledger.get_data_shreds_for_slot(0, 0).unwrap()[0];
+        assert!(!stored_shred.data_complete());
+        assert!(stored_shred.last_in_slot());
+        assert_eq!(entries, ledger.get_any_valid_slot_entries(0, 0));
+    }
 }

ledger/src/shred.rs

@@ -433,6 +433,24 @@ impl Shred {
         }
     }
 
+    #[cfg(test)]
+    pub fn unset_data_complete(&mut self) {
+        if self.is_data() {
+            self.data_header.flags &= !DATA_COMPLETE_SHRED;
+        }
+
+        // Data header starts after the shred common header
+        let mut start = SIZE_OF_COMMON_SHRED_HEADER;
+        let size_of_data_shred_header = SIZE_OF_DATA_SHRED_HEADER;
+        Self::serialize_obj_into(
+            &mut start,
+            size_of_data_shred_header,
+            &mut self.payload,
+            &self.data_header,
+        )
+        .expect("Failed to write data header into shred buffer");
+    }
+
     pub fn data_complete(&self) -> bool {
         if self.is_data() {
             self.data_header.flags & DATA_COMPLETE_SHRED == DATA_COMPLETE_SHRED