When pausing a task during a waiting status, hide the status while paused

We do this for two reasons:
- when popping up a credentials prompt, it looks distracting if the waiting
  status keeps spinning while the user is typing the password
- the task that updates the waiting status periodically would keep the program
  busy, so integration tests would wait forever for the program to become idle
  again

pkg/gui/controllers/helpers/app_status_helper.go

@@ -33,11 +33,32 @@ func (self *AppStatusHelper) Toast(message string) {
 	self.renderAppStatus()
 }
 
+// A custom task for WithWaitingStatus calls; it wraps the original one and
+// hides the status whenever the task is paused, and shows it again when
+// continued.
+type appStatusHelperTask struct {
+	gocui.Task
+	waitingStatusHandle *status.WaitingStatusHandle
+}
+
+// poor man's version of explicitly saying that struct X implements interface Y
+var _ gocui.Task = appStatusHelperTask{}
+
+func (self appStatusHelperTask) Pause() {
+	self.waitingStatusHandle.Hide()
+	self.Task.Pause()
+}
+
+func (self appStatusHelperTask) Continue() {
+	self.Task.Continue()
+	self.waitingStatusHandle.Show()
+}
+
 // withWaitingStatus wraps a function and shows a waiting status while the function is still executing
 func (self *AppStatusHelper) WithWaitingStatus(message string, f func(gocui.Task) error) {
 	self.c.OnWorker(func(task gocui.Task) {
-		self.statusMgr().WithWaitingStatus(message, self.renderAppStatus, func() {
-			if err := f(task); err != nil {
+		self.statusMgr().WithWaitingStatus(message, self.renderAppStatus, func(waitingStatusHandle *status.WaitingStatusHandle) {
+			if err := f(appStatusHelperTask{task, waitingStatusHandle}); err != nil {
 				self.c.OnUIThread(func() error {
 					return self.c.Error(err)
 				})

pkg/gui/status/status_manager.go

@@ -44,11 +44,11 @@ func NewStatusManager() *StatusManager {
 	return &StatusManager{}
 }
 
-func (self *StatusManager) WithWaitingStatus(message string, renderFunc func(), f func()) {
+func (self *StatusManager) WithWaitingStatus(message string, renderFunc func(), f func(*WaitingStatusHandle)) {
 	handle := &WaitingStatusHandle{statusManager: self, message: message, renderFunc: renderFunc, id: -1}
 	handle.Show()
 
-	f()
+	f(handle)
 
 	handle.Hide()
 }