F handle null input to ArrayUtils.combine

Author: actions-user

approvaltests-util-tests/src/test/java/com/spun/util/ArrayUtilsTest.java

@@ -43,6 +43,9 @@ public void testCombineArrays()
     Integer[] ints = new Integer[]{5, 6, 7};
     assertEquals("[1, 5, 6, 7]", Arrays.toString(ArrayUtils.combine(1, ints)));
     assertEquals("[1]", Arrays.toString(ArrayUtils.combine(1)));
+    assertEquals("[null, a, b, c]", Arrays.toString(ArrayUtils.combine(null, "a", "b", "c")));
+    String empty = null;
+    assertEquals("[null]", Arrays.toString(ArrayUtils.combine(empty)));
   }
   @Test
   void testToArray()

approvaltests-util/src/main/java/com/spun/util/ArrayUtils.java

@@ -213,7 +213,9 @@ else if (isEmpty(b))
   }
   public static <T> T[] combine(T a, T... b)
   {
-    final T[] toArray = (T[]) Array.newInstance(a.getClass(), 1);
+    final Class<?> type = a != null ? a.getClass() : b.getClass().getComponentType();
+
+    final T[] toArray = (T[]) Array.newInstance(type, 1);
     toArray[0] = a;
     return combine(toArray, b);
   }