Fix bug in reload mode equality check. Better equality conversion for state variables (#8385)

* Add code

* Add deep equality

* add changeset

* Add code

* add changeset

* Update gradio/utils.py

Co-authored-by: Abubakar Abid <abubakar@huggingface.co>

* Add code

* Add code

* add code

---------

Co-authored-by: gradio-pr-bot <gradio-pr-bot@users.noreply.github.com>
Co-authored-by: Abubakar Abid <abubakar@huggingface.co>

.changeset/ripe-tools-jam.md

@@ -0,0 +1,5 @@
+---
+"gradio": patch
+---
+
+fix:Fix bug in reload mode equality check. Better equality conversion for state variables

gradio/blocks.py

@@ -1726,7 +1726,15 @@ Received outputs:
 
             if block.stateful:
                 if not utils.is_update(predictions[i]):
-                    if block._id not in state or state[block._id] != predictions[i]:
+                    has_change_event = False
+                    for dep in state.blocks_config.fns.values():
+                        if block._id in [t[0] for t in dep.targets if t[1] == "change"]:
+                            has_change_event = True
+                            break
+                    if has_change_event and (
+                        block._id not in state
+                        or not utils.deep_equal(state[block._id], predictions[i])
+                    ):
                         changed_state_ids.append(block._id)
                     state[block._id] = predictions[i]
                 output.append(None)

gradio/utils.py

@@ -46,6 +46,7 @@ from typing import (
 import anyio
 import gradio_client.utils as client_utils
 import httpx
+import orjson
 from gradio_client.documentation import document
 from typing_extensions import ParamSpec
 
@@ -290,6 +291,29 @@ def watchfn(reloader: SourceFileReloader):
         time.sleep(0.05)
 
 
+def deep_equal(a: Any, b: Any) -> bool:
+    """
+    Deep equality check for component values.
+
+    Prefer orjson for performance and compatibility with numpy arrays/dataframes/torch tensors.
+    If objects are not serializable by orjson, fall back to regular equality check.
+    """
+
+    def _serialize(a: Any) -> bytes:
+        return orjson.dumps(
+            a,
+            option=orjson.OPT_SERIALIZE_NUMPY | orjson.OPT_PASSTHROUGH_DATETIME,
+        )
+
+    try:
+        return _serialize(a) == _serialize(b)
+    except TypeError:
+        try:
+            return a == b
+        except Exception:
+            return False
+
+
 def reassign_keys(old_blocks: Blocks, new_blocks: Blocks):
     from gradio.blocks import BlockContext
 
@@ -310,8 +334,10 @@ def reassign_keys(old_blocks: Blocks, new_blocks: Blocks):
                     old_block.__class__ == new_block.__class__
                     and old_block is not None
                     and old_block.key not in assigned_keys
-                    and json.dumps(getattr(old_block, "value", None))
+                    and deep_equal(
-                    == json.dumps(getattr(new_block, "value", None))
+                        getattr(old_block, "value", None),
+                        getattr(new_block, "value", None),
+                    )
                 ):
                     new_block.key = old_block.key
                 else: