fix: potential wrong total time in trace info when the request is invalid (#1017)

Author: git-hulk

request.go

@@ -1251,13 +1251,16 @@ func (r *Request) TraceInfo() TraceInfo {
 RequestAttempt: r.Attempt,
 }
 
-// Calculate the total time accordingly,
-// when connection is reused
-if ct.gotConnInfo.Reused {
-ti.TotalTime = ct.endTime.Sub(ct.getConn)
-} else {
-ti.TotalTime = ct.endTime.Sub(ct.dnsStart)
+// Calculate the total time accordingly when connection is reused,
+// and DNS start and get conn time may be zero if the request is invalid.
+// See issue #1016.
+requestStartTime := r.Time
+if ct.gotConnInfo.Reused && !ct.getConn.IsZero() {
+requestStartTime = ct.getConn
+} else if !ct.dnsStart.IsZero() {
+requestStartTime = ct.dnsStart
 }
+ti.TotalTime = ct.endTime.Sub(requestStartTime)
 
 // Only calculate on successful connections
 if !ct.connectDone.IsZero() {

request_test.go

@@ -1830,6 +1830,18 @@ func TestTraceInfo(t *testing.T) {
 
 })
 
+t.Run("enable trace on invalid request, issue #1016", func(t *testing.T) {
+resp, err := client.R().EnableTrace().Get("unknown://url.com")
+assertNotNil(t, err)
+tr := resp.Request.TraceInfo()
+assertEqual(t, true, tr.DNSLookup == 0)
+assertEqual(t, true, tr.ConnTime == 0)
+assertEqual(t, true, tr.TLSHandshake == 0)
+assertEqual(t, true, tr.ServerTime == 0)
+assertEqual(t, true, tr.ResponseTime == 0)
+assertEqual(t, true, tr.TotalTime > 0 && tr.TotalTime < time.Second)
+})
+
 t.Run("enable trace and debug on request", func(t *testing.T) {
 c, logBuf := dcldb()
 c.SetBaseURL(ts.URL)