anchor.diff:    void visitPackageName(PSEntry name) {
       var packageName = name.value.text;
       if (packageName != null && !isValidPackageName(packageName)) {
  -      rule.reportPubLint(name.value); // arguments: [packageName]
  +      rule.reportPubLint(name.value, arguments: [packageName]);
       }
     }
   }
  
positive.code: ''';
  
  class PubPackageNames extends LintRule {
    // TODO(brianwilkerson) Uncomment the following when `reportPubLint` supports
    //  message arguments.
    // static const LintCode code = LintCode('package_names',
    //     "The package name '{0}' isn't a snake_case identifier.",
    //     correctionMessage:
    //     'Try changing the name to follow the snake_case style.');
    //
    // @override
    // LintCode get lintCode => code;
  
    PubPackageNames()
        : super(
  
negative.code:             description: _desc,
              details: _details,
              group: Group.pub);
  
    @override
    LintCode get lintCode => code;
  
    @override
    PubspecVisitor getPubspecVisitor() => Visitor(this);
  