Couchbase gives badarg error

I created simple couchbase spatial view to get list of report, but it gives {error: "error", reason: "badarg"} error.

Here is my view:-

function (doc, meta) {
    if (doc.type == "report" && doc.location && doc.location.type && doc.location.coordinates) {

          if(doc.location.type=='Point'){ 
             emit(doc.location, {
               summary:doc.summary
              });
          }
    }
}

why this badarg error is coming, same view work on different doc.type