style(langgraph): make format make lint

libs/langgraph/langgraph/_internal/_constants.py

@@ -24,6 +24,7 @@ PREVIOUS = sys.intern("__previous__")
 
 # --- Reserved cache namespaces ---
 CACHE_NS_WRITES = sys.intern("__pregel_ns_writes")
+
 # cache namespace for node writes
 
 # --- Reserved config.configurable keys ---
@@ -77,6 +78,8 @@ CONF = cast(Literal["configurable"], sys.intern("configurable"))
 # key for the configurable dict in RunnableConfig
 NULL_TASK_ID = sys.intern("00000000-0000-0000-0000-000000000000")
 # the task_id to use for writes that are not associated with a task
+RUNTIME_PLACEHOLDER = "__pregel_runtime_placeholder__"
+# placeholder for untracked values replaced at runtime
 
 # redefined to avoid circular import with langgraph.constants
 _TAG_HIDDEN = sys.intern("langsmith:hidden")

libs/langgraph/langgraph/pregel/_algo.py

@@ -57,6 +57,7 @@ from langgraph._internal._constants import (
     RESERVED,
     RESUME,
     RETURN,
+    RUNTIME_PLACEHOLDER,
     TASKS,
 )
 from langgraph._internal._scratchpad import PregelScratchpad
@@ -72,7 +73,6 @@ from langgraph.pregel._log import logger
 from langgraph.pregel._read import INPUT_CACHE_KEY_TYPE, PregelNode
 from langgraph.runtime import DEFAULT_RUNTIME, Runtime
 from langgraph.types import (
-    RUNTIME_PLACEHOLDER,
     All,
     CacheKey,
     CachePolicy,
@@ -1112,11 +1112,14 @@ class LazyAtomicCounter:
                     self._counter = itertools.count(0).__next__
         return self._counter()
 
-def sanitize_untracked_values_in_send(packet: Send, channels: Mapping[str, BaseChannel]) -> Send:
+
+def sanitize_untracked_values_in_send(
+    packet: Send, channels: Mapping[str, BaseChannel]
+) -> Send:
     """Replace any UntrackedValue contents in Send.arg with RUNTIME_PLACEHOLDER for checkpointing.
-    
+
     Send is not typed and arg may be a nested dict."""
-    
+
     if not isinstance(packet.arg, dict):
         # Command
         return packet
@@ -1133,7 +1136,10 @@ def sanitize_untracked_values_in_send(packet: Send, channels: Mapping[str, BaseC
     sanitized_arg = replace(packet.arg)
     return Send(node=packet.node, arg=sanitized_arg)
 
-def rehydrate_untracked_values_in_send(packet: Send, channels: Mapping[str, BaseChannel]) -> Send:
+
+def rehydrate_untracked_values_in_send(
+    packet: Send, channels: Mapping[str, BaseChannel]
+) -> Send:
     """Replace RUNTIME_PLACEHOLDERs in Send.arg with actual untracked values from UntrackedValue channels."""
 
     if not isinstance(packet.arg, dict):
@@ -1141,13 +1147,18 @@ def rehydrate_untracked_values_in_send(packet: Send, channels: Mapping[str, Base
         return packet
 
     # deepcopy to avoid mutating the original packet, as it is later persisted in checkpoints
-    arg_deepcopy = deepcopy(packet.arg) 
+    arg_deepcopy = deepcopy(packet.arg)
+
     def replace(obj: dict[str, Any]) -> dict[str, Any]:
         for k, v in obj.items():
             if isinstance(v, dict):
                 # arg can be nested dicts
                 v = replace(v)
-            if v is RUNTIME_PLACEHOLDER and k in channels and isinstance(channels[k], UntrackedValue):
+            if (
+                v is RUNTIME_PLACEHOLDER
+                and k in channels
+                and isinstance(channels[k], UntrackedValue)
+            ):
                 obj[k] = channels[k].get()
         return obj
 

libs/langgraph/langgraph/pregel/_loop.py

@@ -20,7 +20,6 @@ from typing import (
     TypeVar,
     cast,
 )
-from langgraph.channels.untracked_value import UntrackedValue
 
 from langchain_core.callbacks import AsyncParentRunManager, ParentRunManager
 from langchain_core.runnables import RunnableConfig
@@ -62,6 +61,7 @@ from langgraph._internal._constants import (
 from langgraph._internal._scratchpad import PregelScratchpad
 from langgraph._internal._typing import EMPTY_SEQ, MISSING
 from langgraph.channels.base import BaseChannel
+from langgraph.channels.untracked_value import UntrackedValue
 from langgraph.constants import TAG_HIDDEN
 from langgraph.errors import (
     EmptyInputError,
@@ -75,12 +75,12 @@ from langgraph.pregel._algo import (
     Call,
     GetNextVersion,
     PregelTaskWrites,
-    sanitize_untracked_values_in_send,
     apply_writes,
     checkpoint_null_version,
     increment,
     prepare_next_tasks,
     prepare_single_task,
+    sanitize_untracked_values_in_send,
     should_interrupt,
     task_path_str,
 )
@@ -327,20 +327,15 @@ class PregelLoop:
 
         # We never want to persist untracked values in checkpoints
         # because there is no guarantee that they are serializable
-        def _sanitize(group: WritesT) -> WritesT:
-            out: WritesT = []
-            for c, v in group:
-                # Do not persist UntrackedValue channel writes
-                if isinstance(self.specs.get(c), UntrackedValue):
-                    continue
-                # Sanitize UntrackedValues that are nested within Send packets
-                if c == TASKS and isinstance(v, Send):
-                    out.append((c, sanitize_untracked_values_in_send(v, self.channels)))
-                else:
-                    out.append((c, v))
-            return out
-
-        writes_to_save = _sanitize(writes_to_save)
+        writes_to_save = [
+            # Sanitize UntrackedValues that are nested within Send packets
+            (c, sanitize_untracked_values_in_send(v, self.channels))
+            if c == TASKS and isinstance(v, Send)
+            else (c, v)
+            for c, v in writes_to_save
+            # Do not persist UntrackedValue channel writes
+            if not isinstance(self.specs.get(c), UntrackedValue)
+        ]
 
         # save writes
         self.checkpoint_pending_writes.extend((task_id, c, v) for c, v in writes)

libs/langgraph/langgraph/pregel/main.py

@@ -106,11 +106,11 @@ from langgraph.errors import (
 from langgraph.managed.base import ManagedValueSpec
 from langgraph.pregel._algo import (
     PregelTaskWrites,
-    sanitize_untracked_values_in_send,
     _scratchpad,
     apply_writes,
     local_read,
     prepare_next_tasks,
+    sanitize_untracked_values_in_send,
 )
 from langgraph.pregel._call import identifier
 from langgraph.pregel._checkpoint import (

libs/langgraph/langgraph/types.py

@@ -27,9 +27,6 @@ from langgraph._internal._retry import default_retry_on
 from langgraph._internal._typing import MISSING, DeprecatedKwargs
 from langgraph.warnings import LangGraphDeprecatedSinceV10
 
-# placeholder for untracked values replaced at runtime
-RUNTIME_PLACEHOLDER = "__pregel_runtime_placeholder__"
-
 if TYPE_CHECKING:
     from langgraph.pregel.protocol import PregelProtocol
 

libs/langgraph/tests/test_pregel.py

@@ -13,7 +13,6 @@ from concurrent.futures import ThreadPoolExecutor
 from dataclasses import dataclass, field
 from random import randrange
 from typing import Annotated, Any, Literal, get_type_hints
-from langgraph.channels.untracked_value import UntrackedValue
 
 import pytest
 from langchain_core.language_models import GenericFakeChatModel
@@ -45,6 +44,7 @@ from langgraph.channels.binop import BinaryOperatorAggregate
 from langgraph.channels.ephemeral_value import EphemeralValue
 from langgraph.channels.last_value import LastValue
 from langgraph.channels.topic import Topic
+from langgraph.channels.untracked_value import UntrackedValue
 from langgraph.config import get_stream_writer
 from langgraph.errors import GraphRecursionError, InvalidUpdateError, ParentCommand
 from langgraph.func import entrypoint, task
@@ -8599,6 +8599,7 @@ def test_multiple_writes_same_channel_from_same_node(
         },
     ]
 
+
 def test_send_with_untracked_value(sync_checkpointer: BaseCheckpointSaver):
     """Test that Send objects work correctly with untracked values in state."""
 
@@ -8648,6 +8649,4 @@ def test_send_with_untracked_value(sync_checkpointer: BaseCheckpointSaver):
 
     # Check that the untracked resource is NOT in the final state checkpoint
     state = app.get_state(config)
-    assert (
-        "session_resource" not in state.values
-    )
+    assert "session_resource" not in state.values