core: Add ruff rules for error messages (EM) (#26965)

All auto-fixes

Co-authored-by: Erick Friis <[email protected]>

libs/core/langchain_core/_api/deprecation.py

@@ -51,15 +51,18 @@ def _validate_deprecation_params(
 ) -> None:
     """Validate the deprecation parameters."""
     if pending and removal:
-        raise ValueError("A pending deprecation cannot have a scheduled removal")
+        msg = "A pending deprecation cannot have a scheduled removal"
+        raise ValueError(msg)
     if alternative and alternative_import:
-        raise ValueError("Cannot specify both alternative and alternative_import")
+        msg = "Cannot specify both alternative and alternative_import"
+        raise ValueError(msg)
 
     if alternative_import and "." not in alternative_import:
-        raise ValueError(
+        msg = (
             "alternative_import must be a fully qualified module path. Got "
             f" {alternative_import}"
         )
+        raise ValueError(msg)
 
 
 def deprecated(
@@ -222,7 +225,8 @@ def warn_if_direct_instance(
             if not _obj_type:
                 _obj_type = "attribute"
             if not _name:
-                raise ValueError(f"Field {obj} must have a name to be deprecated.")
+                msg = f"Field {obj} must have a name to be deprecated."
+                raise ValueError(msg)
             old_doc = obj.description
 
             def finalize(wrapper: Callable[..., Any], new_doc: str) -> T:
@@ -241,7 +245,8 @@ def finalize(wrapper: Callable[..., Any], new_doc: str) -> T:
             if not _obj_type:
                 _obj_type = "attribute"
             if not _name:
-                raise ValueError(f"Field {obj} must have a name to be deprecated.")
+                msg = f"Field {obj} must have a name to be deprecated."
+                raise ValueError(msg)
             old_doc = obj.description
 
             def finalize(wrapper: Callable[..., Any], new_doc: str) -> T:
@@ -428,10 +433,11 @@ def warn_deprecated(
     if not pending:
         if not removal:
             removal = f"in {removal}" if removal else "within ?? minor releases"
-            raise NotImplementedError(
+            msg = (
                 f"Need to determine which default deprecation schedule to use. "
                 f"{removal}"
             )
+            raise NotImplementedError(msg)
         else:
             removal = f"in {removal}"
 
@@ -523,9 +529,8 @@ def decorator(f: Callable[_P, _R]) -> Callable[_P, _R]:
         @functools.wraps(f)
         def wrapper(*args: _P.args, **kwargs: _P.kwargs) -> _R:
             if new in kwargs and old in kwargs:
-                raise TypeError(
-                    f"{f.__name__}() got multiple values for argument {new!r}"
-                )
+                msg = f"{f.__name__}() got multiple values for argument {new!r}"
+                raise TypeError(msg)
             if old in kwargs:
                 warn_deprecated(
                     since,

libs/core/langchain_core/beta/runnables/context.py

@@ -59,7 +59,8 @@ def _key_from_id(id_: str) -> str:
     elif wout_prefix.endswith(CONTEXT_CONFIG_SUFFIX_SET):
         return wout_prefix[: -len(CONTEXT_CONFIG_SUFFIX_SET)]
     else:
-        raise ValueError(f"Invalid context config id {id_}")
+        msg = f"Invalid context config id {id_}"
+        raise ValueError(msg)
 
 
 def _config_with_context(
@@ -103,16 +104,15 @@ def _config_with_context(
 
         for dep in deps_by_key[key]:
             if key in deps_by_key[dep]:
-                raise ValueError(
-                    f"Deadlock detected between context keys {key} and {dep}"
-                )
+                msg = f"Deadlock detected between context keys {key} and {dep}"
+                raise ValueError(msg)
         if len(setters) != 1:
-            raise ValueError(f"Expected exactly one setter for context key {key}")
+            msg = f"Expected exactly one setter for context key {key}"
+            raise ValueError(msg)
         setter_idx = setters[0][1]
         if any(getter_idx < setter_idx for _, getter_idx in getters):
-            raise ValueError(
-                f"Context setter for key {key} must be defined after all getters."
-            )
+            msg = f"Context setter for key {key} must be defined after all getters."
+            raise ValueError(msg)
 
         if getters:
             context_funcs[getters[0][0].id] = partial(getter, events[key], values)
@@ -271,9 +271,8 @@ def config_specs(self) -> list[ConfigurableFieldSpec]:
             if spec.id.endswith(CONTEXT_CONFIG_SUFFIX_GET):
                 getter_key = spec.id.split("/")[1]
                 if getter_key in self.keys:
-                    raise ValueError(
-                        f"Circular reference in context setter for key {getter_key}"
-                    )
+                    msg = f"Circular reference in context setter for key {getter_key}"
+                    raise ValueError(msg)
         return super().config_specs + [
             ConfigurableFieldSpec(
                 id=id_,

libs/core/langchain_core/caches.py

@@ -160,7 +160,8 @@ def __init__(self, *, maxsize: Optional[int] = None) -> None:
         """
         self._cache: dict[tuple[str, str], RETURN_VAL_TYPE] = {}
         if maxsize is not None and maxsize <= 0:
-            raise ValueError("maxsize must be greater than 0")
+            msg = "maxsize must be greater than 0"
+            raise ValueError(msg)
         self._maxsize = maxsize
 
     def lookup(self, prompt: str, llm_string: str) -> Optional[RETURN_VAL_TYPE]:

libs/core/langchain_core/callbacks/base.py

@@ -275,9 +275,8 @@ def on_chat_model_start(
         """
         # NotImplementedError is thrown intentionally
         # Callback handler will fall back to on_llm_start if this is exception is thrown
-        raise NotImplementedError(
-            f"{self.__class__.__name__} does not implement `on_chat_model_start`"
-        )
+        msg = f"{self.__class__.__name__} does not implement `on_chat_model_start`"
+        raise NotImplementedError(msg)
 
     def on_retriever_start(
         self,
@@ -523,9 +522,8 @@ async def on_chat_model_start(
         """
         # NotImplementedError is thrown intentionally
         # Callback handler will fall back to on_llm_start if this is exception is thrown
-        raise NotImplementedError(
-            f"{self.__class__.__name__} does not implement `on_chat_model_start`"
-        )
+        msg = f"{self.__class__.__name__} does not implement `on_chat_model_start`"
+        raise NotImplementedError(msg)
 
     async def on_llm_new_token(
         self,

libs/core/langchain_core/callbacks/manager.py

@@ -1510,11 +1510,12 @@ def on_custom_event(
         .. versionadded:: 0.2.14
         """
         if kwargs:
-            raise ValueError(
+            msg = (
                 "The dispatcher API does not accept additional keyword arguments."
                 "Please do not pass any additional keyword arguments, instead "
                 "include them in the data field."
             )
+            raise ValueError(msg)
         if run_id is None:
             run_id = uuid.uuid4()
 
@@ -1989,11 +1990,12 @@ async def on_custom_event(
             run_id = uuid.uuid4()
 
         if kwargs:
-            raise ValueError(
+            msg = (
                 "The dispatcher API does not accept additional keyword arguments."
                 "Please do not pass any additional keyword arguments, instead "
                 "include them in the data field."
             )
+            raise ValueError(msg)
         await ahandle_event(
             self.handlers,
             "on_custom_event",
@@ -2336,11 +2338,12 @@ def _configure(
 
     if v1_tracing_enabled_ and not tracing_v2_enabled_:
         # if both are enabled, can silently ignore the v1 tracer
-        raise RuntimeError(
+        msg = (
             "Tracing using LangChainTracerV1 is no longer supported. "
             "Please set the LANGCHAIN_TRACING_V2 environment variable to enable "
             "tracing instead."
         )
+        raise RuntimeError(msg)
 
     tracer_project = _get_tracer_project()
     debug = _get_debug()
@@ -2519,13 +2522,14 @@ async def foo(inputs):
     # within a tool or a lambda and have the metadata events associated
     # with the parent run rather than have a new run id generated for each.
     if callback_manager.parent_run_id is None:
-        raise RuntimeError(
+        msg = (
             "Unable to dispatch an adhoc event without a parent run id."
             "This function can only be called from within an existing run (e.g.,"
             "inside a tool or a RunnableLambda or a RunnableGenerator.)"
             "If you are doing that and still seeing this error, try explicitly"
             "passing the config parameter to this function."
         )
+        raise RuntimeError(msg)
 
     await callback_manager.on_custom_event(
         name,
@@ -2588,13 +2592,14 @@ def foo(inputs):
     # within a tool or a lambda and have the metadata events associated
     # with the parent run rather than have a new run id generated for each.
     if callback_manager.parent_run_id is None:
-        raise RuntimeError(
+        msg = (
             "Unable to dispatch an adhoc event without a parent run id."
             "This function can only be called from within an existing run (e.g.,"
             "inside a tool or a RunnableLambda or a RunnableGenerator.)"
             "If you are doing that and still seeing this error, try explicitly"
             "passing the config parameter to this function."
         )
+        raise RuntimeError(msg)
     callback_manager.on_custom_event(
         name,
         data,

libs/core/langchain_core/chat_history.py

@@ -157,10 +157,11 @@ def add_message(self, message: BaseMessage) -> None:
             # method, so we should use it.
             self.add_messages([message])
         else:
-            raise NotImplementedError(
+            msg = (
                 "add_message is not implemented for this class. "
                 "Please implement add_message or add_messages."
             )
+            raise NotImplementedError(msg)
 
     def add_messages(self, messages: Sequence[BaseMessage]) -> None:
         """Add a list of messages.

libs/core/langchain_core/document_loaders/base.py

@@ -53,11 +53,12 @@ def load_and_split(
             try:
                 from langchain_text_splitters import RecursiveCharacterTextSplitter
             except ImportError as e:
-                raise ImportError(
+                msg = (
                     "Unable to import from langchain_text_splitters. Please specify "
                     "text_splitter or install langchain_text_splitters with "
                     "`pip install -U langchain-text-splitters`."
-                ) from e
+                )
+                raise ImportError(msg) from e
 
             _text_splitter: TextSplitter = RecursiveCharacterTextSplitter()
         else:
@@ -71,9 +72,8 @@ def lazy_load(self) -> Iterator[Document]:
         """A lazy loader for Documents."""
         if type(self).load != BaseLoader.load:
             return iter(self.load())
-        raise NotImplementedError(
-            f"{self.__class__.__name__} does not implement lazy_load()"
-        )
+        msg = f"{self.__class__.__name__} does not implement lazy_load()"
+        raise NotImplementedError(msg)
 
     async def alazy_load(self) -> AsyncIterator[Document]:
         """A lazy loader for Documents."""

libs/core/langchain_core/documents/base.py

@@ -142,7 +142,8 @@ def source(self) -> Optional[str]:
     def check_blob_is_valid(cls, values: dict[str, Any]) -> Any:
         """Verify that either data or path is provided."""
         if "data" not in values and "path" not in values:
-            raise ValueError("Either data or path must be provided")
+            msg = "Either data or path must be provided"
+            raise ValueError(msg)
         return values
 
     def as_string(self) -> str:
@@ -155,7 +156,8 @@ def as_string(self) -> str:
         elif isinstance(self.data, str):
             return self.data
         else:
-            raise ValueError(f"Unable to get string for blob {self}")
+            msg = f"Unable to get string for blob {self}"
+            raise ValueError(msg)
 
     def as_bytes(self) -> bytes:
         """Read data as bytes."""
@@ -167,7 +169,8 @@ def as_bytes(self) -> bytes:
             with open(str(self.path), "rb") as f:
                 return f.read()
         else:
-            raise ValueError(f"Unable to get bytes for blob {self}")
+            msg = f"Unable to get bytes for blob {self}"
+            raise ValueError(msg)
 
     @contextlib.contextmanager
     def as_bytes_io(self) -> Generator[Union[BytesIO, BufferedReader], None, None]:
@@ -178,7 +181,8 @@ def as_bytes_io(self) -> Generator[Union[BytesIO, BufferedReader], None, None]:
             with open(str(self.path), "rb") as f:
                 yield f
         else:
-            raise NotImplementedError(f"Unable to convert blob {self}")
+            msg = f"Unable to convert blob {self}"
+            raise NotImplementedError(msg)
 
     @classmethod
     def from_path(

libs/core/langchain_core/exceptions.py

@@ -41,10 +41,11 @@ def __init__(
     ):
         super().__init__(error)
         if send_to_llm and (observation is None or llm_output is None):
-            raise ValueError(
+            msg = (
                 "Arguments 'observation' & 'llm_output'"
                 " are required if 'send_to_llm' is True"
             )
+            raise ValueError(msg)
         self.observation = observation
         self.llm_output = llm_output
         self.send_to_llm = send_to_llm