add-dart-lint-validation-rule

name	add-dart-lint-validation-rule
description	Instructions for adding a new validation rule and CLI flag to dart_skills_lint. Use this skill when asked to create a new rule that validates aspects of skills (like frontmatter metadata).
metadata	{"internal":true}

Add a New Validation Rule and Flag

Use this skill when you need to add a new validation rule to the dart_skills_lint package, expose it as a toggleable CLI flag, and verify its behavior.

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🛠️ Step-by-Step Implementation

1. Create the Rule Class

Create a new file in lib/src/rules/ extending SkillRule.

[!TIP] If your rule expects a specific structure in the skill's YAML frontmatter (e.g., inside metadata), document this structure clearly in the class Dart docstring.

// lib/src/rules/my_new_rule.dart

import '../models/analysis_severity.dart';
import '../models/skill_context.dart';
import '../models/skill_rule.dart';
import '../models/validation_error.dart';

class MyNewRule extends SkillRule {
  MyNewRule({super.severity});

  @override
  Future<List<ValidationError>> validate(SkillContext context) async {
    final errors = <ValidationError>[];
    // Add validation logic here using context.rawContent or context.directory
    return errors;
  }
}

Accessing YAML Frontmatter

If your rule needs configuration from the skill's YAML frontmatter, you can access it via context.parsedYaml.

  @override
  Future<List<ValidationError>> validate(SkillContext context) async {
    final errors = <ValidationError>[];
    final yaml = context.parsedYaml;
    if (yaml != null) {
      final metadata = yaml['metadata'];
      if (metadata is Map) {
        // Read your custom config here
      }
    }
    return errors;
  }