Add Dumas JSON array iterator node

tests/test_dumas_json_nodes.py

@@ -2,6 +2,7 @@ import unittest
 
 from dumas_json_nodes import (
     DumasJSONArrayLengthNode,
+    DumasJSONArrayIteratorNode,
     DumasJSONGetValueNode,
     DumasJSONKeysNode,
     DumasJSONMergeObjectsNode,
@@ -73,6 +74,41 @@ class DumasJSONNodeTests(unittest.TestCase):
 
         self.assertEqual(result, (4,))
 
+    def test_array_iterator_fixed_mode_uses_given_index(self):
+        node = DumasJSONArrayIteratorNode()
+
+        result = node.iterate(["a", "b", "c"], 1, "fixed")
+
+        self.assertEqual(result, ("b", 1, 3))
+
+    def test_array_iterator_incr_mode_advances_index(self):
+        node = DumasJSONArrayIteratorNode()
+
+        result = node.iterate(["a", "b", "c"], 1, "incr")
+
+        self.assertEqual(result, ("c", 2, 3))
+
+    def test_array_iterator_decr_mode_decrements_index(self):
+        node = DumasJSONArrayIteratorNode()
+
+        result = node.iterate(["a", "b", "c"], 1, "decr")
+
+        self.assertEqual(result, ("a", 0, 3))
+
+    def test_array_iterator_clamps_out_of_range_index(self):
+        node = DumasJSONArrayIteratorNode()
+
+        result = node.iterate(["a", "b", "c"], 99, "fixed")
+
+        self.assertEqual(result, ("c", 2, 3))
+
+    def test_array_iterator_handles_empty_arrays(self):
+        node = DumasJSONArrayIteratorNode()
+
+        result = node.iterate([], 0, "fixed")
+
+        self.assertEqual(result, (None, -1, 0))
+
 
 if __name__ == "__main__":
     unittest.main()