Given a file path is this file quarantined? To do this we use `getxattr` and look for `com.apple.quarantine` which is applied by File Quarantine-aware applications.

FileMetadataHelpers.swift

//
//  FileMetadataHelpers.swift
//  FileMetadataHelpers
//
//  Created by Brandon Dalton on 10/7/23.
//

import Foundation

/// Helper functions for working with file metadata.
public struct FileMetadataHelpers {

    public enum FileQuarantineStatus {
        /// The file is quarantined.
        case quarantined
        /// The file is not quarantined.
        case notQuarantined
        /// The file was not found.
        case fileNotFound
    }

    /// Checks if a file is quarantined.
    ///
    /// - Parameter filePath: The path to the file to check.
    /// - Returns: A `FileQuarantineStatus` value indicating whether the file is quarantined, not quarantined, or not found.
    public static func isFileQuarantined(filePath: String) -> FileQuarantineStatus {
        let fileManager = FileManager.default
        guard fileManager.fileExists(atPath: filePath) else {
            return .fileNotFound
        }
        
        /// Reference: https://developer.apple.com/library/archive/documentation/System/Conceptual/ManPages_iPhoneOS/man2/getxattr.2.html
        let quarantineAttribute = getxattr(filePath, "com.apple.quarantine", nil, 0, 0, 0)
        return quarantineAttribute > 0 ? .quarantined : .notQuarantined
    }
}