Correct behavior of $append function

Author: rayokota

src/jsonata/functions.py

@@ -2010,15 +2010,9 @@ def append(arg1: Optional[Any], arg2: Optional[Any]) -> Optional[Any]:
             arg1 = utils.Utils.create_sequence(arg1)
         if not (isinstance(arg2, list)):
             arg2 = utils.Utils.JList([arg2])
-        # else
-        #     // Arg2 was a list: add it as a list element (don't flatten)
-        #     ((List)arg1).add((List)arg2)
 
         arg1 = utils.Utils.JList(arg1)  # create a new copy!
-        if isinstance(arg2, utils.Utils.JList) and arg2.cons:
-            arg1.append(arg2)
-        else:
-            arg1.extend(arg2)
+        arg1.extend(arg2)
         return arg1
 
     @staticmethod

tests/array_test.py

@@ -0,0 +1,7 @@
+import jsonata
+
+
+class TestArray:
+
+    def test_array(self):
+        assert jsonata.Jsonata("$.[{ }] ~> $reduce($append)").evaluate([True, True]) == [{}, {}]