[GHC] #14082: -ddump-json does not escape output properly

[GHC]

#14082: -ddump-json does not escape output properly
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           Reporter:  dramforever    |             Owner:  (none)
               Type:  bug            |            Status:  new
           Priority:  normal         |         Milestone:
          Component:  Compiler       |           Version:  8.2.1
           Keywords:                 |  Operating System:  Unknown/Multiple
       Architecture:                 |   Type of failure:  None/Unknown
  Unknown/Multiple                   |
          Test Case:                 |        Blocked By:
           Blocking:                 |   Related Tickets:
Differential Rev(s):                 |         Wiki Page:
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 == Steps to reproduce

 This program

 {{{#!hs
 module StringError where

 q = "string" + "string"
 }}}

 Compiled with `-ddump-json`, produces this JSON output:

 {{{
 [
  {"span": {"file": "tmp.hs","startLine": 3,"startCol": 5,"endLine":
 3,"endCol": 24},"doc": "\u2022 No instance for (Num [Char]) arising f
 rom a use of \u2018+\u2019\n\u2022 In the expression: "string" +
 "string"\n  In an equation for \u2018q\u2019: q = "string" + "string"","
 severity": "SevError","reason": null}]
 }}}

 It is not valid JSON, because `"string"` occured in a JSON string, but the
 quotes are not escaped.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14082>
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