ServerAddress.FromUrl("http://") throws ArgumentOutOfRangeException

[mikeharder]

Repro

ServerAddress.FromUrl("http://")

Expected

Return either null or a valid ServerAddress

Actual

Unhandled Exception: System.ArgumentOutOfRangeException: Length cannot be less than zero.
Parameter name: length
   at System.String.Substring(Int32 startIndex, Int32 length)
   at Microsoft.AspNetCore.Server.Kestrel.ServerAddress.FromUrl(String url)

[khellang]

Don't you think it should throw something for invalid URLs? Returning null could lead to an equally vague NullReferenceException.

[mikeharder]

@khellang: Thanks for the suggestion, we agree ServerAddress.FromUrl() should throw instead of returning null. Tracked by #875.