Code Review Results

✅ Strengths

Well-structured feature with comprehensive test coverage, clear documentation, and thoughtful API design that supports multiple hiding strategies (custom functions, metadata field, and custom field getters).

🚨 Critical Issues

[File: src/hooks/useOptionsList.ts Line: L38]
The recursive filtering function uses unsafe type casting (option as Record<string, any>)[nestedKey] which bypasses TypeScript's type safety. This could lead to runtime errors if the nested property doesn't exist or isn't an array.

Recommendation: Use proper type guards or optional chaining:

function filterOptionsRecursively<T>(
  options: Array<T>,
  isHiddenFn: (option: T) => boolean,
  nestedKey: string,
): Array<T> {
  return options
    .filter((option) => !isHiddenFn(option))
    .map((option) => {
      const nestedOptions = (option as any)?.[nestedKey];
      if (Array.isArray(nestedOptions) && nestedOptions.length > 0) {
        return {
          ...option,
          [nestedKey]: filterOptionsRecursively(nestedOptions, isHiddenFn, nestedKey),
        };
      }
      return option;
    });
}

[File: src/components/Filters/UseFilterOptionsList.tsx Line: L58]
The effect that builds selectedOptionsMap from facet.options doesn't account for hidden options. If an option is hidden but was previously selected (e.g., from URL state), it will be included in the selected map but won't be visible to users. This creates inconsistent state.

Recommendation: Filter out hidden options before building the selected map:

useEffect(() => {
  const newSelectedOptionsMap = {};
  const visibleOptions = facet.options.filter((option) => !isHiddenOptionFn(option));
  visibleOptions.forEach((option) => {
    newSelectedOptionsMap[option.value] = option.status === 'selected';
  });
  setSelectedOptionMap(newSelectedOptionsMap);
  // eslint-disable-next-line react-hooks/exhaustive-deps
}, [facet, isHiddenOptionFn]);

⚠️ Important Issues

[File: src/hooks/useOptionsList.ts Line: L62]
The useMemo dependency array includes nestedOptionsKey which is typically a constant string. While not incorrect, this could cause unnecessary re-filtering. Consider if this dependency is truly needed.

[File: src/hooks/useFilter.ts Line: L45-51]
[File: src/hooks/useGroups.ts Line: L47-53]
[File: src/components/Filters/UseFilterOptionsList.tsx Line: L29-36]
The pattern for combining isHiddenFn and getIsHiddenField is duplicated across three files. This logic should be extracted into a reusable utility function to improve maintainability.

Recommendation: Create a utility function:

// src/utils/filterHelpers.ts
export function createIsHiddenFn<T>(
  customFn?: (item: T) => boolean,
  metadataFn?: (item: T) => boolean | undefined,
): (item: T) => boolean {
  return (item: T) =>
    (typeof customFn === 'function' && customFn(item)) ||
    (typeof metadataFn === 'function' && metadataFn(item)) ||
    false;
}

[File: src/stories/components/Filters/Code Examples.mdx Line: L91]
Documentation states this feature is "intended for conditional rendering per page" but doesn't provide clear guidance on when NOT to use it. The note is good but could be more prominent (e.g., a warning callout).

💡 Suggestions

[File: spec/components/Filters/Filters.test.jsx Line: L757-773]
Test comment says "lowercase 'color'" which is implementation detail leakage. Consider removing the comment or making it more descriptive about why the facet name matters (e.g., "matching the facet name from mockTransformedFacets").

[File: src/hooks/useOptionsList.ts Line: L30-47]
The recursive filtering function would benefit from JSDoc comments explaining the algorithm and edge cases (e.g., what happens with circular references, deeply nested structures).

[File: src/utils/itemFieldGetters.ts Line: L56-66]
Return type annotations are inconsistent - some functions explicitly return boolean | undefined in the type definition but the implementations just use optional chaining. Consider adding explicit return type annotations to the function implementations for clarity:

export function getIsHiddenFilterField(facet: PlpFacet): boolean | undefined {
  return facet?.data?.cio_plp_hidden;
}

[File: spec/hooks/useFilter/useFilter.test.js Line: L299-337]
The test "Should use custom getIsHiddenFilterField from itemFieldGetters" creates a custom wrapper inline. Consider extracting this to a test utility function since this pattern might be useful for other tests.

[General]
Consider adding performance tests or benchmarks for the recursive filtering logic, especially with deeply nested hierarchies (e.g., 5+ levels deep with hundreds of options). The current implementation creates new objects at every level which could be expensive for large datasets.

Overall Assessment: ⚠️ Needs Work

The feature is well-designed and comprehensively tested, but has two critical issues that should be addressed:

1. Type safety issue in recursive filtering
2. State management issue with hidden selected options

These issues could cause runtime errors or UX inconsistencies in production. Once resolved, this will be a solid addition to the codebase.