From 96023296e503c20ccf6701fea13615c5afa96c0f Mon Sep 17 00:00:00 2001
From: Sydney Runkle <sydneymarierunkle@gmail.com>
Date: Wed, 29 Apr 2026 13:53:53 -0400
Subject: [PATCH] refactor: remove unnecessary variable extractions from
 checkpoint load paths

Revert pure-style refactors (local variable hoisting, redundant null
guards, Sequence/list annotation change) that cluttered the DeltaChannel
PR diff without any semantic change.
---
 .../langgraph/checkpoint/postgres/__init__.py |  3 +-
 .../langgraph/checkpoint/postgres/aio.py      | 17 ++-----
 .../langgraph/checkpoint/postgres/base.py     |  3 +-
 .../langgraph/checkpoint/memory/__init__.py   | 48 +++++++------------
 4 files changed, 23 insertions(+), 48 deletions(-)

diff --git a/libs/checkpoint-postgres/langgraph/checkpoint/postgres/__init__.py b/libs/checkpoint-postgres/langgraph/checkpoint/postgres/__init__.py
index 5f3e04af7..cd2fb33de 100644
--- a/libs/checkpoint-postgres/langgraph/checkpoint/postgres/__init__.py
+++ b/libs/checkpoint-postgres/langgraph/checkpoint/postgres/__init__.py
@@ -491,7 +491,6 @@ class PostgresSaver(BasePostgresSaver):
             including its configuration, metadata, parent checkpoint (if any),
             and pending writes.
         """
-        channel_values = self._load_blobs(value["channel_values"])
         return CheckpointTuple(
             {
                 "configurable": {
@@ -504,7 +503,7 @@ class PostgresSaver(BasePostgresSaver):
                 **value["checkpoint"],
                 "channel_values": {
                     **(value["checkpoint"].get("channel_values") or {}),
-                    **channel_values,
+                    **self._load_blobs(value["channel_values"]),
                 },
             },
             value["metadata"],
diff --git a/libs/checkpoint-postgres/langgraph/checkpoint/postgres/aio.py b/libs/checkpoint-postgres/langgraph/checkpoint/postgres/aio.py
index 9b0fd2100..bd3899f78 100644
--- a/libs/checkpoint-postgres/langgraph/checkpoint/postgres/aio.py
+++ b/libs/checkpoint-postgres/langgraph/checkpoint/postgres/aio.py
@@ -450,18 +450,11 @@ class AsyncPostgresSaver(BasePostgresSaver):
             including its configuration, metadata, parent checkpoint (if any),
             and pending writes.
         """
-        thread_id = value["thread_id"]
-        checkpoint_ns = value["checkpoint_ns"]
-        blob_values = value["channel_values"]
-        channel_values: dict[str, Any] = {}
-        if blob_values:
-            channel_values = self._load_blobs(blob_values)
-
         return CheckpointTuple(
             {
                 "configurable": {
-                    "thread_id": thread_id,
-                    "checkpoint_ns": checkpoint_ns,
+                    "thread_id": value["thread_id"],
+                    "checkpoint_ns": value["checkpoint_ns"],
                     "checkpoint_id": value["checkpoint_id"],
                 }
             },
@@ -469,15 +462,15 @@ class AsyncPostgresSaver(BasePostgresSaver):
                 **value["checkpoint"],
                 "channel_values": {
                     **(value["checkpoint"].get("channel_values") or {}),
-                    **channel_values,
+                    **self._load_blobs(value["channel_values"]),
                 },
             },
             value["metadata"],
             (
                 {
                     "configurable": {
-                        "thread_id": thread_id,
-                        "checkpoint_ns": checkpoint_ns,
+                        "thread_id": value["thread_id"],
+                        "checkpoint_ns": value["checkpoint_ns"],
                         "checkpoint_id": value["parent_checkpoint_id"],
                     }
                 }
diff --git a/libs/checkpoint-postgres/langgraph/checkpoint/postgres/base.py b/libs/checkpoint-postgres/langgraph/checkpoint/postgres/base.py
index 3ebafa6e1..50103b7c9 100644
--- a/libs/checkpoint-postgres/langgraph/checkpoint/postgres/base.py
+++ b/libs/checkpoint-postgres/langgraph/checkpoint/postgres/base.py
@@ -247,8 +247,7 @@ class BasePostgresSaver(BaseCheckpointSaver[str]):
         )
 
     def _load_blobs(
-        self,
-        blob_values: Sequence[tuple[bytes, bytes, bytes]],
+        self, blob_values: list[tuple[bytes, bytes, bytes]]
     ) -> dict[str, Any]:
         if not blob_values:
             return {}
diff --git a/libs/checkpoint/langgraph/checkpoint/memory/__init__.py b/libs/checkpoint/langgraph/checkpoint/memory/__init__.py
index 011f871e7..0b8593c3e 100644
--- a/libs/checkpoint/langgraph/checkpoint/memory/__init__.py
+++ b/libs/checkpoint/langgraph/checkpoint/memory/__init__.py
@@ -9,7 +9,7 @@ from collections import defaultdict
 from collections.abc import AsyncIterator, Iterator, Sequence
 from contextlib import AbstractAsyncContextManager, AbstractContextManager, ExitStack
 from types import TracebackType
-from typing import Any, cast
+from typing import Any
 
 from langchain_core.runnables import RunnableConfig
 
@@ -255,16 +255,13 @@ class InMemorySaver(
                 checkpoint, metadata, parent_checkpoint_id = saved
                 writes = self.writes[(thread_id, checkpoint_ns, checkpoint_id)].values()
                 checkpoint_: Checkpoint = self.serde.loads_typed(checkpoint)
-                channel_values = self._load_blobs(
-                    thread_id,
-                    checkpoint_ns,
-                    checkpoint_["channel_versions"],
-                )
                 return CheckpointTuple(
                     config=config,
                     checkpoint={
                         **checkpoint_,
-                        "channel_values": channel_values,
+                        "channel_values": self._load_blobs(
+                            thread_id, checkpoint_ns, checkpoint_["channel_versions"]
+                        ),
                     },
                     metadata=self.serde.loads_typed(metadata),
                     pending_writes=[
@@ -288,26 +285,19 @@ class InMemorySaver(
                 checkpoint, metadata, parent_checkpoint_id = checkpoints[checkpoint_id]
                 writes = self.writes[(thread_id, checkpoint_ns, checkpoint_id)].values()
                 checkpoint_ = self.serde.loads_typed(checkpoint)
-                resolved_config = cast(
-                    RunnableConfig,
-                    {
+                return CheckpointTuple(
+                    config={
                         "configurable": {
                             "thread_id": thread_id,
                             "checkpoint_ns": checkpoint_ns,
                             "checkpoint_id": checkpoint_id,
                         }
                     },
-                )
-                channel_values = self._load_blobs(
-                    thread_id,
-                    checkpoint_ns,
-                    checkpoint_["channel_versions"],
-                )
-                return CheckpointTuple(
-                    config=resolved_config,
                     checkpoint={
                         **checkpoint_,
-                        "channel_values": channel_values,
+                        "channel_values": self._load_blobs(
+                            thread_id, checkpoint_ns, checkpoint_["channel_versions"]
+                        ),
                     },
                     metadata=self.serde.loads_typed(metadata),
                     pending_writes=[
@@ -402,27 +392,21 @@ class InMemorySaver(
 
                     checkpoint_: Checkpoint = self.serde.loads_typed(checkpoint)
 
-                    list_config = cast(
-                        RunnableConfig,
-                        {
+                    yield CheckpointTuple(
+                        config={
                             "configurable": {
                                 "thread_id": thread_id,
                                 "checkpoint_ns": checkpoint_ns,
                                 "checkpoint_id": checkpoint_id,
                             }
                         },
-                    )
-                    channel_values = self._load_blobs(
-                        thread_id,
-                        checkpoint_ns,
-                        checkpoint_["channel_versions"],
-                    )
-
-                    yield CheckpointTuple(
-                        config=list_config,
                         checkpoint={
                             **checkpoint_,
-                            "channel_values": channel_values,
+                            "channel_values": self._load_blobs(
+                                thread_id,
+                                checkpoint_ns,
+                                checkpoint_["channel_versions"],
+                            ),
                         },
                         metadata=metadata,
                         parent_config=(