Function resolveReference

packages/cli/src/linter/model/handler.ts:377–397

* Resolve a token reference with chained resolution and cycle detection. * Returns null if the reference cannot be resolved (not found or circular).

(
  symbolTable: Map<string, ResolvedValue>,
  path: string,
  visited: Set<string>,
  depth: number = 0,
)

 * Returns null if the reference cannot be resolved (not found or circular).
 */
function resolveReference(
  symbolTable: Map<string, ResolvedValue>,
  path: string,
  visited: Set<string>,
  depth: number = 0,
): ResolvedValue | null {
  if (depth > MAX_REFERENCE_DEPTH) return null;
  if (visited.has(path)) return null; // Circular reference
  visited.add(path);

  const value = symbolTable.get(path);
  if (value === undefined) return null;

  // If the value is itself a reference string, follow the chain
  if (typeof value === 'string' && isTokenReference(value)) {
    const innerPath = value.slice(1, -1);
    return resolveReference(symbolTable, innerPath, visited, depth + 1);
  }

  return value;
}

/**
 * WCAG 2.1 contrast ratio between two resolved colors.