Test which reproduce the problem

runner/reporter.go

@@ -154,7 +154,7 @@ func (r *Reporter) Run() {
 				r.lats = append(r.lats, res.duration.Seconds())
 				r.errors = append(r.errors, "")
 				r.statuses = append(r.statuses, res.status)
-				r.timestamps = append(r.timestamps, time.Now())
+				r.timestamps = append(r.timestamps, res.timestamp)
 			}
 		}
 	}

runner/reporter_test.go

@@ -1,6 +1,7 @@
 package runner
 
 import (
+	"context"
 	"encoding/json"
 	"testing"
 	"time"
@@ -26,3 +27,31 @@ func TestReport_MarshalJSON(t *testing.T) {
 	expected := `{"date":"2006-01-02T15:04:00-07:00","options":{"insecure":false,"binary":false,"CPUs":0},"count":1000,"total":10000000000,"average":500000000,"fastest":10000000,"slowest":1000000000,"rps":34567.89,"errorDistribution":null,"statusCodeDistribution":null,"latencyDistribution":null,"histogram":null,"details":null}`
 	assert.Equal(t, expected, string(json))
 }
+
+func TestReport_CorrectDetails(t *testing.T) {
+	callResultsChan := make(chan *callResult)
+	config, _ := newConfig("call", "host")
+	reporter := newReporter(callResultsChan, config)
+
+	go reporter.Run()
+
+	cr1 := callResult{
+		status:    "OK",
+		duration:  time.Millisecond * 100,
+		err:       nil,
+		timestamp: time.Now(),
+	}
+	callResultsChan <- &cr1
+	cr2 := callResult{
+		status:    "DeadlineExceeded",
+		duration:  time.Millisecond * 500,
+		err:       context.DeadlineExceeded,
+		timestamp: time.Now(),
+	}
+	callResultsChan <- &cr2
+
+	report := reporter.Finalize("stop reason", time.Second)
+	assert.Equal(t, 2, len(report.Details))
+	assert.Equal(t, ResultDetail{Error: "", Latency: cr1.duration, Status: cr1.status, Timestamp: cr1.timestamp}, report.Details[0])
+	assert.Equal(t, ResultDetail{Error: cr2.err.Error(), Latency: cr2.duration, Status: cr2.status, Timestamp: cr2.timestamp}, report.Details[1])
+}

runner/requester.go

@@ -28,9 +28,10 @@ const maxResult = 1000000
 
 // result of a call
 type callResult struct {
-	err      error
-	status   string
-	duration time.Duration
+	err       error
+	status    string
+	duration  time.Duration
+	timestamp time.Time
 }
 
 // Requester is used for doing the requests

runner/stats_handler.go

@@ -38,7 +38,7 @@ func (c *statsHandler) HandleRPC(ctx context.Context, rs stats.RPCStats) {
 			st = s.Code().String()
 		}
 
-		c.results <- &callResult{rpcStats.Error, st, duration}
+		c.results <- &callResult{rpcStats.Error, st, duration, end}
 	}
 }