Assign colors (as shown in the macOS Finder) to files

FinderFileColors.swift

import Foundation

enum FinderColor: Int {
    case noColor = 0
    case grey = 1
    case green = 2
    case purple = 3
    case blue = 4
    case yellow = 5
    case red = 6
    case orange = 7
}

extension URL {
    /// Assigns a color to the file/directory this URL identifies.
    ///
    /// The color is displayed as a label by the macOS Finder.
    /// macOS stores this tag as an extended attribute on the file.
    mutating func setFinderColor(_ color: FinderColor) throws {
        var resourceValues = URLResourceValues()
        resourceValues.labelNumber = color.rawValue
        try setResourceValues(resourceValues)
    }
}