Add JSON parsing helper to Integration Tests

test/integration.rb

@@ -6,6 +6,7 @@
 ##
 require 'minitest/autorun'
 require 'open3'
+require 'json'
 
 class WhatWebTest < Minitest::Test
 
@@ -13,6 +14,13 @@ class WhatWebTest < Minitest::Test
     @test_host = 'whatweb.net'
   end
 
+  def valid_json?(json)
+    JSON.parse(json)
+    return true
+  rescue JSON::ParserError => e
+    return false
+  end
+
   def test_version
     p = IO.popen(['./whatweb', '--version'], 'r+')
     res = p.read.to_s