Fix PreviewAny escaping non-ASCII text in dict and list previews (#15513)

comfy_extras/nodes_preview_any.py

@@ -29,7 +29,7 @@ class PreviewAny():
             value = str(source)
         elif source is not None:
             try:
-                value = json.dumps(source, indent=4)
+                value = json.dumps(source, indent=4, ensure_ascii=False)
             except Exception:
                 try:
                     value = str(source)

tests-unit/comfy_extras_test/nodes_preview_any_test.py

@@ -0,0 +1,30 @@
+from unittest.mock import patch, MagicMock
+
+mock_nodes = MagicMock()
+mock_nodes.MAX_RESOLUTION = 16384
+mock_server = MagicMock()
+
+with patch.dict("sys.modules", {"nodes": mock_nodes, "server": mock_server}):
+    from comfy_extras.nodes_preview_any import PreviewAny
+
+
+class TestPreviewAnyMain:
+    @staticmethod
+    def _exec(source) -> dict:
+        return PreviewAny().main(source)
+
+    def test_dict_keeps_non_ascii(self):
+        result = self._exec({"greeting": "你好"})
+        assert "你好" in result["ui"]["text"][0]
+        assert "\\u" not in result["ui"]["text"][0]
+        assert result["result"][0] == result["ui"]["text"][0]
+
+    def test_list_keeps_non_ascii(self):
+        result = self._exec(["你好", "こんにちは"])
+        assert "こんにちは" in result["result"][0]
+        assert "\\u" not in result["result"][0]
+
+    def test_string_passthrough(self):
+        result = self._exec("你好")
+        assert result["ui"]["text"][0] == "你好"
+        assert result["result"][0] == "你好"