Add new testcases

Author: wendelinwemhoener

src/test/java/seedu/duke/DukeTest.java

@@ -1,12 +1,37 @@
 package seedu.duke;
 
 import static org.junit.jupiter.api.Assertions.assertTrue;
+import static org.junit.jupiter.api.Assertions.assertFalse;
 
 import org.junit.jupiter.api.Test;
+import seedu.duke.flashcard.FlashcardComponent;
+import seedu.duke.flashcard.command.UnknownCommand;
+
+import java.util.ArrayList;
 
 class DukeTest {
     @Test
     public void sampleTest() {
         assertTrue(true);
     }
+
+    @Test
+    public void testFlashcardComponent_isResponsible_notResponsible() {
+        FlashcardComponent flashcardComponent = new FlashcardComponent(
+                new ArrayList<>());
+
+        assertFalse(flashcardComponent.isResponsible("dfdfdfdfdf"));
+        assertFalse(flashcardComponent.isResponsible("help me"));
+        assertFalse(flashcardComponent.isResponsible(" "));
+    }
+
+    @Test
+    public void testFlashcardComponent_isResponsible_responsible() {
+        FlashcardComponent flashcardComponent = new FlashcardComponent(
+                new ArrayList<>());
+
+        assertTrue(flashcardComponent.isResponsible("create flashcard"));
+        assertTrue(flashcardComponent.isResponsible("create flashcard  "));
+        assertTrue(flashcardComponent.isResponsible("list flashcards"));
+    }
 }