test: Empty draw channel after every DoEvent() and before resizing th…

…e screen

This is necessary since DoEvent() isn't called in a loop like in the main
application, but as one-shot only.

cmd/micro/micro_test.go

@@ -90,6 +90,10 @@ func startup(args []string) (tcell.SimulationScreen, error) {
 		return nil, err
 	}
 
+	for len(screen.DrawChan()) > 0 {
+		<-screen.DrawChan()
+	}
+
 	s.InjectResize()
 	handleEvent()
 
@@ -107,7 +111,12 @@ func handleEvent() {
 	if e != nil {
 		screen.Events <- e
 	}
+
 	DoEvent()
+
+	for len(screen.DrawChan()) > 0 {
+		<-screen.DrawChan()
+	}
 }
 
 func injectKey(key tcell.Key, r rune, mod tcell.ModMask) {