How to handle Unparsable JSON string in groovy

I'd use the following function to validate json

import groovy.json.JsonSlurper

Boolean isValidJson(jsonString){
	result = true
	try{
		new JsonSlurper().parseText(jsonString)
	}
	catch(Exception e){
		result = false
	}
	return result
}

And then call the validation before passing the values to assertEquals:

assert isValidJson(response) == true
assert isValidJson(step_response) == true
JSONAssert.assertEquals(step_response,response,false)

Instead of asserting it to true, you can also just use an if() to handle the malformatted json as you see fit.