#247 -- Add failed test

src/test/java/ru/ulstu/StreamApiUtilsTest.java

@@ -16,4 +16,12 @@ public class StreamApiUtilsTest {
 
         assertEquals(integersInitial, integers);
     }
+
+    @Test
+    public void filedTestMappingByDay() {
+        List<Integer> integersInitial = List.of(1);
+        List<Integer> integers = StreamApiUtils.convert(List.of("1", "2"), Integer::valueOf);
+
+        assertEquals(integersInitial, integers);
+    }
 }