anchor.diff:    }
   
     final requestedBuilder = options["builder"];
  -  final namedConfigurations =
  +  final requestedNamedConfigurations =
         (options["named-configuration"] as List).cast<String>();
     final localConfiguration = options["local-configuration"] as String;
   
  -  if (requestedBuilder == null && namedConfigurations.isEmpty) {
  +  if (requestedBuilder == null && requestedNamedConfigurations.isEmpty) {
       printUsage(parser,
           error: "Please specify either a configuration (-n) or "
               "a builder (-b)");
       return;
     }
   
  -  if (localConfiguration != null && namedConfigurations.length > 1) {
  +  if (localConfiguration != null && requestedNamedConfigurations.length > 1) {
       printUsage(parser,
           error: "Local configuration (-N) can only be used with a"
               " single named configuration (-n)");
  
positive.code:     exitCode = 1;
      return;
    }
    // Print information about the resolved builders to compare with.
    for (final builder in configurations.builders) {
      if (localConfiguration != null) {
  
negative.code:       branches,
        buildersConfigurations,
        options["branch"],
        requestedNamedConfigurations,
        requestedBuilder);
    if (configurations == null) {
      // No valid configuration could be found. The error has already been
  