json.dart doesn't escape all control characters #1850
Description
This issue was originally filed by [email protected]
In json.dart, the functions _needsEscape and _escape fail to deal with control characters other than new line '\n' and carriage return '\r' (incorrectly referred to in the source code a sLINE_FEED -- which is a synonym for newline).
According to the JSON specification, all control characters (char codes between 0 and 31) must be escaped, either as \b, \f, \n, \r, \t or as \uxxxx.