created test for checking currentQuestionNr value

src/test/java/Gui/GameGuiTest.java

@@ -4,6 +4,8 @@ import static org.junit.jupiter.api.Assertions.*;
 
 import java.awt.GridBagConstraints;
 import java.awt.Insets;
+import java.io.File;
+import java.io.FileWriter;
 
 import org.junit.jupiter.api.BeforeAll;
 import org.junit.jupiter.api.BeforeEach;
@@ -58,4 +60,20 @@ class GameGuiTest {
         gameGui.highScore();
         assertEquals(expectedHighScore, gameGui.highScore);
     }
+	
+	@Test
+    public void testCreateShowQuestion() throws Exception{
+
+            File file;
+            file = File.createTempFile("temp", ".txt");
+            FileWriter writer = new FileWriter(file);
+            writer.write("1\n");
+            writer.write("2\n");
+            writer.write("3\n");
+            writer.close();
+            GameGui.currentQuestion = 1;
+            gameGui.createShowQuestion(1 ,file.getAbsolutePath());
+            assertEquals("Frage 1: 1 Euro", GameGui.CurrentQuestionNrLabel.getText());
+
+    }
 }