Fix returning copies of a component instance from a prediction function (#6940)

* add test

* add changeset

---------

Co-authored-by: gradio-pr-bot <gradio-pr-bot@users.noreply.github.com>

.changeset/tangy-spoons-hug.md

@@ -0,0 +1,5 @@
+---
+"gradio": patch
+---
+
+fix:Fix returning copies of a component instance from a prediction function

gradio/blocks.py

@@ -1429,7 +1429,7 @@ Received outputs:
                     )
 
                 if isinstance(prediction_value, Block):
-                    prediction_value = prediction_value.constructor_args
+                    prediction_value = prediction_value.constructor_args.copy()
                     prediction_value["__type__"] = "update"
                 if utils.is_update(prediction_value):
                     if output_id in state:

test/test_blocks.py

@@ -1603,3 +1603,24 @@ def test_emptry_string_api_name_gets_set_as_fn_name():
         t1.change(test_fn, t1, t2, api_name="")
 
     assert demo.dependencies[0]["api_name"] == "test_fn"
+
+
+def test_blocks_postprocessing_with_copies_of_component_instance():
+    # Test for: https://github.com/gradio-app/gradio/issues/6608
+    with gr.Blocks() as demo:
+        chatbot = gr.Chatbot()
+        chatbot2 = gr.Chatbot()
+        chatbot3 = gr.Chatbot()
+        clear = gr.Button("Clear")
+
+        def clear_func():
+            return tuple([gr.Chatbot(value=[])] * 3)
+
+        clear.click(
+            fn=clear_func, outputs=[chatbot, chatbot2, chatbot3], api_name="clear"
+        )
+
+        assert (
+            demo.postprocess_data(0, [gr.Chatbot(value=[])] * 3, None)
+            == [{"value": [], "__type__": "update"}] * 3
+        )