p2p/conn: add a test for MakeSecretConnection (#4829)

Refs #4154

libs/async/async.go

@@ -2,6 +2,7 @@ package async
 
 import (
 	"fmt"
+	"runtime"
 	"sync/atomic"
 )
 
@@ -143,7 +144,10 @@ func Parallel(tasks ...Task) (trs *TaskResultSet, ok bool) {
 				if pnk := recover(); pnk != nil {
 					atomic.AddInt32(numPanics, 1)
 					// Send panic to taskResultCh.
-					taskResultCh <- TaskResult{nil, fmt.Errorf("panic in task %v", pnk)}
+					const size = 64 << 10
+					buf := make([]byte, size)
+					buf = buf[:runtime.Stack(buf, false)]
+					taskResultCh <- TaskResult{nil, fmt.Errorf("panic in task %v : %s", pnk, buf)}
 					// Closing taskResultCh lets trs.Wait() work.
 					close(taskResultCh)
 					// Decrement waitgroup.

libs/async/async_test.go

@@ -139,7 +139,7 @@ func checkResult(t *testing.T, taskResultSet *TaskResultSet, index int,
 	case err != nil:
 		assert.Equal(t, err.Error(), taskResult.Error.Error(), taskName)
 	case pnk != nil:
-		assert.Equal(t, pnk, taskResult.Error.Error(), taskName)
+		assert.Contains(t, taskResult.Error.Error(), pnk, taskName)
 	default:
 		assert.Nil(t, taskResult.Error, taskName)
 	}