sr-5397.swift

var inStr:String
var outStr:String

// bad IP-literal (there are no square brackets around the address)
inStr = "2606:2800:220:1:248:1893:25c8:1946"
outStr = inStr.addingPercentEncoding(withAllowedCharacters: .urlHostAllowed)!
// outStr = "2606%3A2800%3A220%3A1%3A248%3A1893%3A25c8%3A1946"

// valid IP-literal (there are square brackets around the address)
inStr = "[2606:2800:220:1:248:1893:25c8:1946]"
outStr = inStr.addingPercentEncoding(withAllowedCharacters: .urlHostAllowed)!
// outStr = "[2606:2800:220:1:248:1893:25c8:1946]" 

// valid IPv4address (all decimal digits and periods)
inStr = "93.184.216.34";
outStr = inStr.addingPercentEncoding(withAllowedCharacters: .urlHostAllowed)!
// outStr = "93.184.216.34" 

// reg-name with no characters that need to be percent encoded
inStr = "www.example.com";
outStr = inStr.addingPercentEncoding(withAllowedCharacters: .urlHostAllowed)!
// outStr = "www.example.com"

// reg-name with characters that need to be percent encoded
inStr = "💩.la";
outStr = inStr.addingPercentEncoding(withAllowedCharacters: .urlHostAllowed)!
// outStr = "%F0%9F%92%A9.la"

// the first ':' does not have to be percent-encoded because it is before the first '/'
inStr = "/foo:bar/foo:bar";
outStr = inStr.addingPercentEncoding(withAllowedCharacters: .urlPathAllowed)!
// outStr = "/foo:bar/foo:bar"

// the first ':' has to be percent-encoded because it is before the first '/'
inStr = "foo:bar/foo:bar";
outStr = inStr.addingPercentEncoding(withAllowedCharacters: .urlPathAllowed)!
// outStr = "foo%3Abar/foo:bar"

// the ';' has to be percent-encoded for backwards compatibility with CFURL and NSURL which parse to an older deprecated standard that included a parameter component starting at the first ';' character
inStr = "a;b";
outStr = inStr.addingPercentEncoding(withAllowedCharacters: .urlPathAllowed)!
// outStr = "a%3Bb"