[supervisor] Add last task output to failure message

components/supervisor/pkg/supervisor/tasks.go

@@ -67,6 +67,7 @@ type task struct {
 	command     string
 	successChan chan taskSuccess
 	title       string
+	lastOutput  string
 }
 
 type headlessTaskProgressReporter interface {
@@ -290,7 +291,7 @@ func (tm *tasksManager) Run(ctx context.Context, wg *sync.WaitGroup, successChan
 					msg = err.Error()
 				}
 
-				t.successChan <- taskFailed(msg)
+				t.successChan <- taskFailed(fmt.Sprintf("%s: %s", msg, t.lastOutput))
 			}
 			taskLog.Info("task terminal has been closed")
 			tm.setTaskState(t, api.TaskState_closed)
@@ -308,7 +309,6 @@ func (tm *tasksManager) Run(ctx context.Context, wg *sync.WaitGroup, successChan
 		select {
 		case <-ctx.Done():
 			success = taskFailed(ctx.Err().Error())
-			break
 		case taskResult := <-task.successChan:
 			if taskResult.Failed() {
 				success = success.Fail(string(taskResult))
@@ -469,6 +469,7 @@ func (tm *tasksManager) watch(task *task, terminal *terminal.Term) {
 			data := string(buf[:n])
 			fileWriter.Write(buf[:n])
 			if tm.reporter != nil {
+				task.lastOutput = string(buf[:n])
 				tm.reporter.write(data, task, terminal)
 			}
 		}