Use shell job for terminal callback

Fixes #2529

cmd/micro/micro.go

@@ -388,7 +388,6 @@ func DoEvent() {
 	var event tcell.Event
 
 	// Display everything
-	screen.DrawLock.Lock()
 	screen.Screen.Fill(' ', config.DefStyle)
 	screen.Screen.HideCursor()
 	action.Tabs.Display()
@@ -398,7 +397,6 @@ func DoEvent() {
 	action.MainTab().Display()
 	action.InfoBar.Display()
 	screen.Screen.Show()
-	screen.DrawLock.Unlock()
 
 	// Check for new events
 	select {

internal/screen/screen.go

@@ -24,7 +24,6 @@ var Events chan (tcell.Event)
 
 // The lock is necessary since the screen is polled on a separate thread
 var lock sync.Mutex
-var DrawLock sync.Mutex
 
 // drawChan is a channel that will cause the screen to redraw when
 // written to even if no event user event has occurred
@@ -121,7 +120,6 @@ func TempFini() bool {
 	if !screenWasNil {
 		Screen.Fini()
 		Lock()
-		DrawLock.Lock()
 		Screen = nil
 	}
 	return screenWasNil
@@ -132,7 +130,6 @@ func TempStart(screenWasNil bool) {
 	if !screenWasNil {
 		Init()
 		Unlock()
-		DrawLock.Unlock()
 	}
 }
 

internal/shell/terminal.go

@@ -128,7 +128,13 @@ func (t *Terminal) Close() {
 	// call the lua function that the user has given as a callback
 	if t.getOutput {
 		if t.callback != nil {
-			t.callback(t.output.String())
+			Jobs <- JobFunction{
+				Function: func(out string, args []interface{}) {
+					t.callback(out)
+				},
+				Output: t.output.String(),
+				Args:   nil,
+			}
 		}
 	}
 }