diff 20-plugin-json.t ../../MozRepl-0.06-882RqE/t/20-plugin-json.t 
17c17
<     is($repl->json({ source => MozRepl::Util->javascript_value({a => 1, b => 2})}), q|"{"a":1,"b":2}"|);
---
>     is($repl->json({ source => MozRepl::Util->javascript_value({a => 1, b => 2})}), q|{"a":1,"b":2}|);