core[patch]: Fix runnable map ser/de (#20631)

libs/core/langchain_core/runnables/base.py

@@ -2136,7 +2136,7 @@ def _seq_input_schema(
                 **{
                     k: (v.annotation, v.default)
                     for k, v in next_input_schema.__fields__.items()
-                    if k not in first.mapper.steps
+                    if k not in first.mapper.steps__
                 },
             )
     elif isinstance(first, RunnablePick):
@@ -2981,11 +2981,11 @@ def mul_three(x: int) -> int:
                 print(output)  # noqa: T201
     """
 
-    steps: Mapping[str, Runnable[Input, Any]]
+    steps__: Mapping[str, Runnable[Input, Any]]
 
     def __init__(
         self,
-        __steps: Optional[
+        steps__: Optional[
             Mapping[
                 str,
                 Union[
@@ -3001,10 +3001,10 @@ def __init__(
             Mapping[str, Union[Runnable[Input, Any], Callable[[Input], Any]]],
         ],
     ) -> None:
-        merged = {**__steps} if __steps is not None else {}
+        merged = {**steps__} if steps__ is not None else {}
         merged.update(kwargs)
         super().__init__(  # type: ignore[call-arg]
-            steps={key: coerce_to_runnable(r) for key, r in merged.items()}
+            steps__={key: coerce_to_runnable(r) for key, r in merged.items()}
         )
 
     @classmethod
@@ -3022,12 +3022,12 @@ class Config:
     def get_name(
         self, suffix: Optional[str] = None, *, name: Optional[str] = None
     ) -> str:
-        name = name or self.name or f"RunnableParallel<{','.join(self.steps.keys())}>"
+        name = name or self.name or f"RunnableParallel<{','.join(self.steps__.keys())}>"
         return super().get_name(suffix, name=name)
 
     @property
     def InputType(self) -> Any:
-        for step in self.steps.values():
+        for step in self.steps__.values():
             if step.InputType:
                 return step.InputType
 
@@ -3038,14 +3038,14 @@ def get_input_schema(
     ) -> Type[BaseModel]:
         if all(
             s.get_input_schema(config).schema().get("type", "object") == "object"
-            for s in self.steps.values()
+            for s in self.steps__.values()
         ):
             # This is correct, but pydantic typings/mypy don't think so.
             return create_model(  # type: ignore[call-overload]
                 self.get_name("Input"),
                 **{
                     k: (v.annotation, v.default)
-                    for step in self.steps.values()
+                    for step in self.steps__.values()
                     for k, v in step.get_input_schema(config).__fields__.items()
                     if k != "__root__"
                 },
@@ -3059,13 +3059,13 @@ def get_output_schema(
         # This is correct, but pydantic typings/mypy don't think so.
         return create_model(  # type: ignore[call-overload]
             self.get_name("Output"),
-            **{k: (v.OutputType, None) for k, v in self.steps.items()},
+            **{k: (v.OutputType, None) for k, v in self.steps__.items()},
         )
 
     @property
     def config_specs(self) -> List[ConfigurableFieldSpec]:
         return get_unique_config_specs(
-            spec for step in self.steps.values() for spec in step.config_specs
+            spec for step in self.steps__.values() for spec in step.config_specs
         )
 
     def get_graph(self, config: Optional[RunnableConfig] = None) -> Graph:
@@ -3074,7 +3074,7 @@ def get_graph(self, config: Optional[RunnableConfig] = None) -> Graph:
         graph = Graph()
         input_node = graph.add_node(self.get_input_schema(config))
         output_node = graph.add_node(self.get_output_schema(config))
-        for step in self.steps.values():
+        for step in self.steps__.values():
             step_graph = step.get_graph()
             step_graph.trim_first_node()
             step_graph.trim_last_node()
@@ -3096,7 +3096,7 @@ def get_graph(self, config: Optional[RunnableConfig] = None) -> Graph:
     def __repr__(self) -> str:
         map_for_repr = ",\n  ".join(
             f"{k}: {indent_lines_after_first(repr(v), '  ' + k + ': ')}"
-            for k, v in self.steps.items()
+            for k, v in self.steps__.items()
         )
         return "{\n  " + map_for_repr + "\n}"
 
@@ -3127,7 +3127,7 @@ def invoke(
         # gather results from all steps
         try:
             # copy to avoid issues from the caller mutating the steps during invoke()
-            steps = dict(self.steps)
+            steps = dict(self.steps__)
             with get_executor_for_config(config) as executor:
                 futures = [
                     executor.submit(
@@ -3170,7 +3170,7 @@ async def ainvoke(
         # gather results from all steps
         try:
             # copy to avoid issues from the caller mutating the steps during invoke()
-            steps = dict(self.steps)
+            steps = dict(self.steps__)
             results = await asyncio.gather(
                 *(
                     step.ainvoke(
@@ -3199,7 +3199,7 @@ def _transform(
         config: RunnableConfig,
     ) -> Iterator[AddableDict]:
         # Shallow copy steps to ignore mutations while in progress
-        steps = dict(self.steps)
+        steps = dict(self.steps__)
         # Each step gets a copy of the input iterator,
         # which is consumed in parallel in a separate thread.
         input_copies = list(safetee(input, len(steps), lock=threading.Lock()))
@@ -3264,7 +3264,7 @@ async def _atransform(
         config: RunnableConfig,
     ) -> AsyncIterator[AddableDict]:
         # Shallow copy steps to ignore mutations while in progress
-        steps = dict(self.steps)
+        steps = dict(self.steps__)
         # Each step gets a copy of the input iterator,
         # which is consumed in parallel in a separate thread.
         input_copies = list(atee(input, len(steps), lock=asyncio.Lock()))

libs/core/langchain_core/runnables/passthrough.py

@@ -369,7 +369,9 @@ def get_name(
         self, suffix: Optional[str] = None, *, name: Optional[str] = None
     ) -> str:
         name = (
-            name or self.name or f"RunnableAssign<{','.join(self.mapper.steps.keys())}>"
+            name
+            or self.name
+            or f"RunnableAssign<{','.join(self.mapper.steps__.keys())}>"
         )
         return super().get_name(suffix, name=name)
 
@@ -488,7 +490,7 @@ def _transform(
         **kwargs: Any,
     ) -> Iterator[Dict[str, Any]]:
         # collect mapper keys
-        mapper_keys = set(self.mapper.steps.keys())
+        mapper_keys = set(self.mapper.steps__.keys())
         # create two streams, one for the map and one for the passthrough
         for_passthrough, for_map = safetee(input, 2, lock=threading.Lock())
 
@@ -544,7 +546,7 @@ async def _atransform(
         **kwargs: Any,
     ) -> AsyncIterator[Dict[str, Any]]:
         # collect mapper keys
-        mapper_keys = set(self.mapper.steps.keys())
+        mapper_keys = set(self.mapper.steps__.keys())
         # create two streams, one for the map and one for the passthrough
         for_passthrough, for_map = atee(input, 2, lock=asyncio.Lock())
         # create map output stream

libs/core/tests/unit_tests/runnables/__snapshots__/test_fallbacks.ambr

@@ -21,7 +21,7 @@
           "RunnableParallel"
         ],
         "kwargs": {
-          "steps": {
+          "steps__": {
             "buz": {
               "lc": 1,
               "type": "not_implemented",
@@ -569,7 +569,7 @@
           "RunnableParallel"
         ],
         "kwargs": {
-          "steps": {
+          "steps__": {
             "text": {
               "lc": 1,
               "type": "constructor",

libs/core/tests/unit_tests/runnables/__snapshots__/test_runnable.ambr

@@ -2051,7 +2051,7 @@
           "RunnableParallel"
         ],
         "kwargs": {
-          "steps": {
+          "steps__": {
             "key": {
               "lc": 1,
               "type": "not_implemented",
@@ -2073,7 +2073,7 @@
                 "RunnableParallel"
               ],
               "kwargs": {
-                "steps": {
+                "steps__": {
                   "question": {
                     "lc": 1,
                     "type": "not_implemented",
@@ -4459,7 +4459,7 @@
           "RunnableParallel"
         ],
         "kwargs": {
-          "steps": {
+          "steps__": {
             "key": {
               "lc": 1,
               "type": "not_implemented",
@@ -4481,7 +4481,7 @@
                 "RunnableParallel"
               ],
               "kwargs": {
-                "steps": {
+                "steps__": {
                   "question": {
                     "lc": 1,
                     "type": "not_implemented",
@@ -8760,7 +8760,7 @@
           "RunnableParallel"
         ],
         "kwargs": {
-          "steps": {
+          "steps__": {
             "question": {
               "lc": 1,
               "type": "constructor",
@@ -9860,7 +9860,7 @@
           "RunnableParallel"
         ],
         "kwargs": {
-          "steps": {
+          "steps__": {
             "chat": {
               "lc": 1,
               "type": "not_implemented",
@@ -10352,7 +10352,7 @@
           "RunnableParallel"
         ],
         "kwargs": {
-          "steps": {
+          "steps__": {
             "chat": {
               "lc": 1,
               "type": "constructor",

libs/core/tests/unit_tests/runnables/test_runnable.py

@@ -35,6 +35,7 @@
     FakeStreamingListLLM,
 )
 from langchain_core.load import dumpd, dumps
+from langchain_core.load.load import loads
 from langchain_core.messages import (
     AIMessage,
     AIMessageChunk,
@@ -76,7 +77,7 @@
     add,
     chain,
 )
-from langchain_core.runnables.base import RunnableSerializable
+from langchain_core.runnables.base import RunnableMap, RunnableSerializable
 from langchain_core.runnables.utils import Input, Output
 from langchain_core.tools import BaseTool, tool
 from langchain_core.tracers import (
@@ -3553,6 +3554,9 @@ async def test_map_astream_iterator_input() -> None:
     assert final_value.get("llm") == "i'm a textbot"
     assert final_value.get("passthrough") == llm_res
 
+    simple_map = RunnableMap(passthrough=RunnablePassthrough())
+    assert loads(dumps(simple_map)) == simple_map
+
 
 def test_with_config_with_config() -> None:
     llm = FakeListLLM(responses=["i'm a textbot"])