added new test case for deleteStation() & code for saved station delete until there is only one station in savedPlaylist

src/main/java/device/radioPlayer/RadioPlayer.java

@@ -187,9 +187,19 @@ public class RadioPlayer implements Device {
 
     public String saveStation() {
         if (savedPlaylist.contains(playedStation)) return "Station " + playedStation + " is already saved";
-        else
-            savedPlaylist.add(playedStation);
+        else savedPlaylist.add(playedStation);
         regionPlaylist.clear();
         return "Station " + playedStation + " is saved in your Station list";
     }
+
+
+    public String deleteStation() {
+        String station = playedStation;
+        if ((savedPlaylist.size()) > 1) {
+            savedPlaylist.remove(playedStation);
+            playedStation = savedPlaylist.get(0);
+            return "Station: 0" + (savedPlaylist.indexOf(playedStation) + 1) + " " + station + " has been deleted";
+        } else return " Last Station: 01 " + station + " can´t by deleted";
+    }
+
 }

src/test/java/device/radioPlayer/RadioPlayerTest.java

@@ -199,8 +199,8 @@ class RadioPlayerTest {
     void testSaveStation(String testName, RadioPlayer testRp, String testTyp, String expectedResult) {
         String savedStation;
         if (testTyp.equals("normal")) {
-        savedStation = testRp.savedPlaylist.get(testRp.savedPlaylist.size() - 1);}
-        else savedStation = Boolean.toString(testRp.regionPlaylist.isEmpty());
+            savedStation = testRp.savedPlaylist.get(testRp.savedPlaylist.size() - 1);
+        } else savedStation = Boolean.toString(testRp.regionPlaylist.isEmpty());
         assertThat(savedStation).describedAs(testName).isEqualTo(expectedResult);
     }
 
@@ -221,4 +221,27 @@ class RadioPlayerTest {
         );
     }
 
+    @ParameterizedTest
+    @MethodSource("deleteStationOptions")
+    void testDeleteStation(String testName, RadioPlayer testRp, String testTyp, Boolean expectedResult) {
+        Boolean savedStation;
+        if (testTyp.equals("delete")) {
+            savedStation = testRp.savedPlaylist.contains("YouFM");
+        } else savedStation = testRp.savedPlaylist.contains("MegaHits");
+        assertThat(savedStation).describedAs(testName).isEqualTo(expectedResult);
+    }
+
+    static Stream<Arguments> deleteStationOptions() {
+        RadioPlayer rp = new RadioPlayer();
+        rp.deleteStation();
+        RadioPlayer rp1 = new RadioPlayer();
+        rp1.deleteStation();
+        rp1.deleteStation();
+        rp1.deleteStation();
+
+        return Stream.of(
+                Arguments.of("Test for delete station in saved playlist", rp, "delete", false),
+                Arguments.of("Test for not delete station in saved playlist if this is the last station", rp1, "noDelete", true)
+        );
+    }
 }