Testing silenced errors

packages/notus/lib/src/document.dart

     assert(index >= 0 && length > 0);
     // TODO: need a heuristic rule to ensure last line-break.
     final change = _heuristics.applyDeleteRules(this, index, length);
-    if (change.isNotEmpty) compose(change, ChangeSource.local);
+    // Delete rules are allowed to prevent the edit.
+//    if (change.isNotEmpty) {
+      compose(change, ChangeSource.local);
+//    }
     return change;
   }
 

packages/notus/pubspec.yaml

 
 dev_dependencies:
   test: ^1.0.0
-  test_coverage: ^0.2.0
+  test_coverage: ^0.2.1

packages/zefyr/lib/src/widgets/controller.dart

   void replaceText(int index, int length, String text,
       {TextSelection selection}) {
     Delta delta;
+
     if (length > 0 || text.isNotEmpty) {
       delta = document.replace(index, length, text);
     }
+
     if (selection != null) {
       if (delta == null) {
         _updateSelectionSilent(selection, source: ChangeSource.local);