Not able to save the result/report into .txt file

[vipinkatiyarknp]

snippet from Gruntfile.js. reporterOutput line is commented, if we uncomment this line, then no task is executing. And how to save the report in the .txt file?

// Run tests
nodeunit: {
all: ['<%= app.test %>/*_test.js'],
options: {
reporter: 'default',
//reporterOutput: '<%= app.test %>/results/<%= grunt.template.today("yyyymmdd") %>-test-results.txt'
}
},

[vipinkatiyarknp]

One more thing I have analysed, all task is executing on the console and indicating us on the console like this
? smokeTest
? loadHostTest
? urlformattingTest
? parseMetaTest
? crawlTest -------- not executing?? because its newer coming on the console.