Improved tag validation and normalization

Author: thomas-bartlett

src/convert_to_ide_formats.py

@@ -38,19 +38,19 @@ def sync_plugin_metadata(version: str) -> None:
 
 def matches_tag_filter(rule_tags: list[str], filter_tags: list[str]) -> bool:
     """
-    Check if rule has all required tags (case-insensitive AND logic).
+    Check if rule has all required tags (AND logic).
     
     Args:
-        rule_tags: List of tags from the rule (already lowercase from parsing)
-        filter_tags: List of tags to filter by
+        rule_tags: List of tags from the rule (already normalized to lowercase)
+        filter_tags: List of tags to filter by (already normalized to lowercase)
     
     Returns:
         True if rule has all filter tags (or no filter), False otherwise
     """
     if not filter_tags:
         return True  # No filter means all pass
 
-    return all(tag.lower() in rule_tags for tag in filter_tags)
+    return all(tag in rule_tags for tag in filter_tags)
 
 
 def update_skill_md(language_to_rules: dict[str, list[str]], skill_path: str) -> None:
@@ -351,10 +351,10 @@ def _resolve_source_paths(args) -> list[Path]:
 
     # Convert all sources
     aggregated = {"success": [], "errors": [], "skipped": []}
-    # Parse comma-separated tags
+    # Parse comma-separated tags and normalize to lowercase
     filter_tags = None
     if cli_args.tags:
-        filter_tags = [tag.strip() for tag in cli_args.tags.split(",") if tag.strip()]
+        filter_tags = [tag.strip().lower() for tag in cli_args.tags.split(",") if tag.strip()]
 
     # Print tag filter info if active
     if filter_tags:

src/utils.py

@@ -62,20 +62,27 @@ def validate_tags(tags, filename=None) -> list[str]:
     Validate tags list and return normalized (lowercase) tags.
     
     Args:
-        tags: The tags value to validate (should be a list)
+        tags: The tags value to validate (should be a non-empty list)
         filename: Optional filename for better error messages
     
     Returns:
         List of normalized (lowercase) tags
     
     Raises:
-        ValueError: If tags are invalid (wrong type, contain whitespace, empty, etc.)
+        ValueError: If tags are invalid (wrong type, empty list, contain whitespace, etc.)
+    
+    Note:
+        An empty tags list (tags: []) is considered invalid. If you have no tags,
+        omit the 'tags' field entirely from the frontmatter.
     """
     context = f" in {filename}" if filename else ""
 
     if not isinstance(tags, list):
         raise ValueError(f"'tags' must be a list{context}")
 
+    if not tags:
+        raise ValueError(f"'tags' list cannot be empty{context}. Omit the field if you have no tags.")
+    
     normalized = []
     for tag in tags:
         if not isinstance(tag, str):
@@ -89,7 +96,7 @@ def validate_tags(tags, filename=None) -> list[str]:
 
         normalized.append(tag.lower())
 
-    return normalized
+    return list(set(normalized))
 
 
 def get_version_from_pyproject() -> str: