anchor.diff:  
     @override
     void visitSimpleStringLiteral(SimpleStringLiteral node) {
  -    AstNode parent = node.parent;
  +    var parent = node.parent;
       if (parent is NamespaceDirective && parent.uri == node) {
  -      String partialUri = _extractPartialUri(node);
  +      var partialUri = _extractPartialUri(node);
         if (partialUri != null) {
           _addDartSuggestions();
           if (UriContributor.suggestFilePaths) {
  
positive.code:             // Quoted empty string
              visitSimpleStringLiteral(uri);
            } else {
              String data = request.sourceContents;
              if (end == data.length) {
                String ch = data[end - 1];
                if (ch != '"' && ch != "'") {
                  // Insertion point at end of file
                  // and missing closing quote on non-empty string
  
negative.code:     }
    }
  
    void _addSuggestion(String completion, {int relevance}) {
      if (request.useNewRelevance) {
        relevance ??= defaultRelevance;
      } else {
        relevance ??= DART_RELEVANCE_DEFAULT;
      }
      suggestions.add(CompletionSuggestion(CompletionSuggestionKind.IMPORT,
          relevance, completion, completion.length, 0, false, false));
    }
  