Additional logging to search index updates. (#1980)

Author: isoos

app/lib/search/updater.dart

@@ -111,7 +111,7 @@ class BatchIndexUpdater implements TaskRunner {
       _batch.clear();
       _taskCount += tasks.length;
       _logger.info('Updating index with ${tasks.length} packages '
-          '[example: ${tasks.first.package}]');
+          '[${tasks.map((t) => t.package)}]');
       final List<PackageDocument> docs = (await searchBackend
               .loadDocuments(tasks.map((t) => t.package).toList()))
           .where((doc) => doc != null)
@@ -120,9 +120,12 @@ class BatchIndexUpdater implements TaskRunner {
       await packageIndex.addPackages(docs);
       final removedPackages = tasks.map((t) => t.package).toSet()
         ..removeAll(docs.map((pd) => pd.package));
-      for (String package in removedPackages) {
-        _snapshot.remove(package);
-        await packageIndex.removePackage(package);
+      if (removedPackages.isNotEmpty) {
+        _logger.info('Removing: $removedPackages');
+        for (String package in removedPackages) {
+          _snapshot.remove(package);
+          await packageIndex.removePackage(package);
+        }
       }
       final bool doMerge =
           _firstScanCount != null && _taskCount >= _firstScanCount;