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Test::JSON - Test JSON data


Version 0.11


 use Test::JSON;

 is_valid_json $json,                 '... json is well formed';
 is_json       $json, $expected_json, '... and it matches what we expected';


  • is_valid_json

  • is_json


JavaScript Object Notation (JSON) is a lightweight data interchange format. Test::JSON makes it easy to verify that you have built valid JSON and that it matches your expected output.

See for more information.



 is_valid_json $json, '... json is well formed';

Test passes if the string passed is valid JSON.


 is_json $json, $expected_json, '... and it matches what we expected';

Test passes if the two JSON strings are valid JSON and evaluate to the same data structure.

Test::Differences is used to provide easy diagnostics of why the JSON structures did not match. For example:

   Failed test '... and identical JSON should match'
   in t/10testjson.t at line 14.
 | Elt|Got                        |Expected                   |
 |   0|{                          |{                          |
 |   1|  bool => '1',             |  bool => '1',             |
 |   2|  description => bless( {  |  description => bless( {  |
 |   3|    value => undef         |    value => undef         |
 |   4|  }, 'JSON::NotString' ),  |  }, 'JSON::NotString' ),  |
 |   5|  id => '1',               |  id => '1',               |
 *   6|  name => 'foo'            |  name => 'fo'             *
 |   7|}                          |}                          |


Curtis "Ovid" Poe, <>


Please report any bugs or feature requests to, or through the web interface at I will be notified, and then you'll automatically be notified of progress on your bug as I make changes.


This test module uses JSON::Any and Test::Differences.


The development of this module was sponsored by Kineticode,, the leading provider of services for the Bricolage content management system,

Thanks to Makamaka Hannyaharamitu for a patch to make this work with JSON 2.0.

Thanks to Stevan Little for suggesting a switch to JSON::Any. This makes it easier for this module to work with whatever JSON module you have installed.


Copyright 2005-2007 Curtis "Ovid" Poe, all rights reserved.

This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.