URL.init(string:) handling of empty strings has changed in Swift 6

[rnro]

Initializing a URL from an empty string in Swift 6 on Linux now returns a non-nil URL value. In earlier Swift versions and on macOS it returns nil.

On Linux Swift 5.10:

  1> import Foundation
  2> let u = Foundation.URL(string: "")
  [snip]
  3> print(u)
nil

On Linux Swift 6.0.1:

  1> import Foundation
  2> let u = Foundation.URL(string: "")
  [snip]
  3> print(u)
Optional()