Unexpected token in JSON - Hmmm

Received error

An invalid JSON is sent in the request.body, error: please ensure that you have wrapped all JSON property names in quotes. details: Unexpected token in JSON at position 592

Turns out the offending string was

"address2": "FedEx Account # 370000740   \t BU#16051",

But there is nothing wrong with that string, it's valid JSON, ugly and bad practice to store that data there, but valid JSON.

From the IETF specification:

The representation of strings is similar to conventions used in the C
   family of programming languages.  A string begins and ends with
   quotation marks.  All Unicode characters may be placed within the
   quotation marks, except for the characters that must be escaped:
   quotation mark, reverse solidus, and the control characters (U+0000
   through U+001F).

It goes on to enumerate the characters required to be escaped:

char = unescaped /
          escape (
              %x22 /          ; "    quotation mark  U+0022
              %x5C /          ; \    reverse solidus U+005C
              %x2F /          ; /    solidus         U+002F
              %x62 /          ; b    backspace       U+0008
              %x66 /          ; f    form feed       U+000C
              %x6E /          ; n    line feed       U+000A
              %x72 /          ; r    carriage return U+000D
              %x74 /          ; t    tab             U+0009
              %x75 4HEXDIG )  ; uXXXX                U+XXXX

So, seems like an incorrect error.

I also wanted to mention that reporting the position is better than nothing, but the reported position doesn't correspond to the 'pretty' JSON we see in the UI. I tried various minification techniques to try to zero in on "position 592" but could never get right to it. A nice enhancement would be to bracket the offending position and show a substring excerpt, like 20 characters before and after the offending position. Just an idea.