Function collectPatternIdentifiers

packages/js-runtime/src/ast-walker.ts:83–123

* Collect identifiers from destructuring patterns

(
  pattern: Record<string, unknown>,
  declared: Set<string>,
)

 * Collect identifiers from destructuring patterns
 */
function collectPatternIdentifiers(
  pattern: Record<string, unknown>,
  declared: Set<string>,
): void {
  if (pattern.type === 'Identifier') {
    declared.add(pattern.name as string);
  } else if (pattern.type === 'ObjectPattern') {
    const properties = pattern.properties as Array<Record<string, unknown>>;
    for (const prop of properties) {
      if (prop.type === 'ObjectProperty') {
        collectPatternIdentifiers(
          prop.value as Record<string, unknown>,
          declared,
        );
      } else if (prop.type === 'RestElement') {
        collectPatternIdentifiers(
          prop.argument as Record<string, unknown>,
          declared,
        );
      }
    }
  } else if (pattern.type === 'ArrayPattern') {
    const elements = pattern.elements as Array<Record<string, unknown> | null>;
    for (const elem of elements) {
      if (elem) {
        collectPatternIdentifiers(elem, declared);
      }
    }
  } else if (pattern.type === 'RestElement') {
    collectPatternIdentifiers(
      pattern.argument as Record<string, unknown>,
      declared,
    );
  } else if (pattern.type === 'AssignmentPattern') {
    // Default parameter values: (x = 5) => ...
    collectPatternIdentifiers(
      pattern.left as Record<string, unknown>,
      declared,
    );
  }
}

/**
 * Check if an identifier is used as a property key (not a value reference)