String Escape and Unescape

string+escaping.swift

import Cocoa
let given =     "{\n\t\"test\": \"this 😃 \\ \",\n\r\t\"\'testing\': 1\r\n}\\ \0 \\"
let expected = #"{\n\t\"test\": \"this 😃 \\ \",\n\r\t\"\'testing\': 1\r\n}\\ \0 \\"#
let expectedAscii = #"{\n\t\"test\": \"this \u{0001F603} \\ \",\n\r\t\"\'testing\': 1\r\n}\\ \0 \\"#

extension String {
    private static let escapedChars = [
        (#"\0"#, "\0"),
        (#"\t"#, "\t"),
        (#"\n"#, "\n"),
        (#"\r"#, "\r"),
        (#"\""#, "\""),
        (#"\'"#, "\'"),
        (#"\\"#, "\\")
    ]
    var escaped: String {
        self.unicodeScalars.map { $0.escaped(asASCII: false) }.joined()
    }
    var asciiEscaped: String {
        self.unicodeScalars.map { $0.escaped(asASCII: true) }.joined()
    }
    var unescaped: String {
        var result: String = self
        String.escapedChars.forEach {
            result = result.replacingOccurrences(of: $0.0, with: $0.1)
        }
        return result
    }
}

print(expected == given.escaped)
print(expectedAscii == given.asciiEscaped)
print(given.escaped.unescaped == given)
print(expected.unescaped == given)
print(expected.unescaped.escaped == expected)