Merge commit 'd5b13dadc8b57b1d4ebb73dce23c7b406e771cf9' into HEAD

src/main/java/device/cdPlayer/CDPlayer.java

@@ -52,7 +52,14 @@ public class CDPlayer implements Device {
 
     @Override
     public void prev() {
-
+        List<String> playList =  Arrays.asList(loadedCD.getPlayList());
+        int actualIndex=playList.indexOf(actualPlayTrack);
+        if(actualIndex>0){
+            actualIndex-=1;
+        }else{
+            actualIndex=0;
+        }
+        this.actualPlayTrack=playList.get(actualIndex);
     }
 
     @Override

src/test/java/device/cdPlayer/CDPlayerTest.java

@@ -197,4 +197,35 @@ class CDPlayerTest {
         );
     }
 
+    @ParameterizedTest
+    @MethodSource("prevTestData")
+    void prevTest(String testName,String testDirection, CDPlayer _cdPlayer,int anzClicks, String expectedResult){
+        if(testDirection.equals("StartingBySecondSong")) {
+            _cdPlayer.next();
+        }
+        if(testDirection.equals("StartingByThirdSong")) {
+            _cdPlayer.next();
+            _cdPlayer.next();
+        }
+        for (int i = 0; i < anzClicks; i++) {
+            _cdPlayer.prev();
+        }
+        assertThat(_cdPlayer.getActualPlayTrack()).describedAs(testName).isEqualTo(expectedResult);
+    }
+    static Stream<Arguments> prevTestData () {
+
+        String[] audioPlayList = new String[]{"Audio 01", "Audio 02", "Audio 03", "Audio 04", "Audio 05"};
+        CD audioCD = new CD("Audio", audioPlayList);
+
+        CDPlayer cdPlayer1 = new CDPlayer();
+        cdPlayer1.tapOnCdFlap();
+        cdPlayer1.setCD(audioCD);
+        cdPlayer1.tapOnCdFlap();
+
+        return Stream.of(
+                Arguments.of("[getActualPlayTrack() after 1x prev() starting by secondSong] => FirstSongSelected", "StartingBySecondSong", cdPlayer1, 1, cdPlayer1.getSongByNumber(0)),
+                Arguments.of("[getActualPlayTrack() after 2x prev() starting by thirdSong] => FirstSongSelected", "StartingByThirdSong", cdPlayer1, 2, cdPlayer1.getSongByNumber(0)),
+                Arguments.of("[getActualPlayTrack() after 1x prev() starting by firstSong] => FirstSongSelected", "StartingByFirstSong", cdPlayer1, 1, cdPlayer1.getSongByNumber(0))
+        );
+    }
 }