refactor: simplify boomer runner

internal/boomer/runner.go

@@ -201,20 +201,17 @@ type localRunner struct {
 	stopChan chan bool
 }
 
-func newLocalRunner(tasks []*Task, rateLimiter RateLimiter, spawnCount int, spawnRate float64) (r *localRunner) {
-	r = &localRunner{}
-	r.setTasks(tasks)
-	r.spawnRate = spawnRate
-	r.spawnCount = spawnCount
-	r.stopChan = make(chan bool)
-
-	if rateLimiter != nil {
-		r.rateLimitEnabled = true
-		r.rateLimiter = rateLimiter
+func newLocalRunner(spawnCount int, spawnRate float64) *localRunner {
+	return &localRunner{
+		runner: runner{
+			state:      stateInit,
+			spawnRate:  spawnRate,
+			spawnCount: spawnCount,
+			stats:      newRequestStats(),
+			outputs:    make([]Output, 0),
+		},
+		stopChan: make(chan bool),
 	}
-
-	r.stats = newRequestStats()
-	return r
 }
 
 func (r *localRunner) start() {
@@ -240,6 +237,7 @@ func (r *localRunner) start() {
 	var ticker = time.NewTicker(reportStatsInterval)
 	for {
 		select {
+		// record stats
 		case t := <-r.stats.transactionChan:
 			r.stats.logTransaction(t.name, t.success, t.elapsedTime, t.contentSize)
 		case m := <-r.stats.requestSuccessChan:
@@ -247,28 +245,34 @@ func (r *localRunner) start() {
 		case n := <-r.stats.requestFailureChan:
 			r.stats.logRequest(n.requestType, n.name, n.responseTime, 0)
 			r.stats.logError(n.requestType, n.name, n.errMsg)
+		// report stats
 		case <-ticker.C:
 			data := r.stats.collectReportData()
 			data["user_count"] = atomic.LoadInt32(&r.currentClientsNum)
 			data["state"] = atomic.LoadInt32(&r.state)
 			r.outputOnEevent(data)
+		// stop
 		case <-r.stopChan:
+			atomic.StoreInt32(&r.state, stateQuitting)
+
 			// stop previous goroutines without blocking
 			// those goroutines will exit when r.safeRun returns
 			close(quitChan)
+
 			// stop rate limiter
 			if r.rateLimitEnabled {
 				r.rateLimiter.Stop()
 			}
+
 			// output teardown
 			r.outputOnStop()
+
+			atomic.StoreInt32(&r.state, stateStopped)
 			return
 		}
 	}
 }
 
 func (r *localRunner) stop() {
-	atomic.StoreInt32(&r.state, stateQuitting)
 	close(r.stopChan)
-	atomic.StoreInt32(&r.state, stateStopped)
 }