langchain: use mypy strict checking with exemptions (#31018)

* Use strict checking and exclude some rules as TODOs
* Fix imports not exposed in `__all__`

Co-authored-by: Eugene Yurtsev <eyurtsev@gmail.com>

libs/langchain/langchain/agents/initialize.py

@@ -11,7 +11,8 @@ from langchain_core.tools import BaseTool
 from langchain._api.deprecation import AGENT_DEPRECATION_WARNING
 from langchain.agents.agent import AgentExecutor
 from langchain.agents.agent_types import AgentType
-from langchain.agents.loading import AGENT_TO_CLASS, load_agent
+from langchain.agents.loading import load_agent
+from langchain.agents.types import AGENT_TO_CLASS
 
 
 @deprecated(

libs/langchain/langchain/agents/openai_functions_agent/base.py

@@ -13,11 +13,11 @@ from langchain_core.messages import (
 )
 from langchain_core.prompts import BasePromptTemplate
 from langchain_core.prompts.chat import (
-    BaseMessagePromptTemplate,
     ChatPromptTemplate,
     HumanMessagePromptTemplate,
     MessagesPlaceholder,
 )
+from langchain_core.prompts.message import BaseMessagePromptTemplate
 from langchain_core.runnables import Runnable, RunnablePassthrough
 from langchain_core.tools import BaseTool
 from langchain_core.utils.function_calling import convert_to_openai_function

libs/langchain/langchain/agents/openai_functions_multi_agent/base.py

@@ -17,11 +17,11 @@ from langchain_core.messages import (
 )
 from langchain_core.prompts import BasePromptTemplate
 from langchain_core.prompts.chat import (
-    BaseMessagePromptTemplate,
     ChatPromptTemplate,
     HumanMessagePromptTemplate,
     MessagesPlaceholder,
 )
+from langchain_core.prompts.message import BaseMessagePromptTemplate
 from langchain_core.tools import BaseTool
 from pydantic import model_validator
 from typing_extensions import Self

libs/langchain/langchain/agents/output_parsers/json.py

@@ -5,7 +5,7 @@ from typing import Union
 
 from langchain_core.agents import AgentAction, AgentFinish
 from langchain_core.exceptions import OutputParserException
-from langchain_core.output_parsers.json import parse_json_markdown
+from langchain_core.utils.json import parse_json_markdown
 
 from langchain.agents.agent import AgentOutputParser
 

libs/langchain/langchain/callbacks/manager.py

@@ -2,6 +2,7 @@ from __future__ import annotations
 
 from typing import TYPE_CHECKING, Any
 
+from langchain_core.callbacks import Callbacks
 from langchain_core.callbacks.manager import (
     AsyncCallbackManager,
     AsyncCallbackManagerForChainGroup,
@@ -18,7 +19,6 @@ from langchain_core.callbacks.manager import (
     CallbackManagerForLLMRun,
     CallbackManagerForRetrieverRun,
     CallbackManagerForToolRun,
-    Callbacks,
     ParentRunManager,
     RunManager,
     ahandle_event,

libs/langchain/langchain/callbacks/tracers/base.py

@@ -1,5 +1,6 @@
 """Base interfaces for tracing runs."""
 
-from langchain_core.tracers.base import BaseTracer, TracerException
+from langchain_core.exceptions import TracerException
+from langchain_core.tracers.base import BaseTracer
 
 __all__ = ["BaseTracer", "TracerException"]

libs/langchain/langchain/chains/base.py

@@ -27,7 +27,7 @@ from langchain_core.runnables import (
     ensure_config,
     run_in_executor,
 )
-from langchain_core.runnables.utils import create_model
+from langchain_core.utils.pydantic import create_model
 from pydantic import (
     BaseModel,
     ConfigDict,

libs/langchain/langchain/chains/combine_documents/base.py

@@ -11,7 +11,7 @@ from langchain_core.callbacks import (
 from langchain_core.documents import Document
 from langchain_core.prompts import BasePromptTemplate, PromptTemplate
 from langchain_core.runnables.config import RunnableConfig
-from langchain_core.runnables.utils import create_model
+from langchain_core.utils.pydantic import create_model
 from langchain_text_splitters import RecursiveCharacterTextSplitter, TextSplitter
 from pydantic import BaseModel, Field
 

libs/langchain/langchain/chains/combine_documents/map_reduce.py

@@ -8,7 +8,7 @@ from langchain_core._api import deprecated
 from langchain_core.callbacks import Callbacks
 from langchain_core.documents import Document
 from langchain_core.runnables.config import RunnableConfig
-from langchain_core.runnables.utils import create_model
+from langchain_core.utils.pydantic import create_model
 from pydantic import BaseModel, ConfigDict, model_validator
 
 from langchain.chains.combine_documents.base import BaseCombineDocumentsChain

libs/langchain/langchain/chains/combine_documents/map_rerank.py

@@ -9,7 +9,7 @@ from langchain_core._api import deprecated
 from langchain_core.callbacks import Callbacks
 from langchain_core.documents import Document
 from langchain_core.runnables.config import RunnableConfig
-from langchain_core.runnables.utils import create_model
+from langchain_core.utils.pydantic import create_model
 from pydantic import BaseModel, ConfigDict, model_validator
 from typing_extensions import Self
 

libs/langchain/langchain/evaluation/agents/trajectory_eval_chain.py

@@ -16,10 +16,10 @@ from typing import (
 )
 
 from langchain_core.agents import AgentAction
+from langchain_core.callbacks import Callbacks
 from langchain_core.callbacks.manager import (
     AsyncCallbackManagerForChainRun,
     CallbackManagerForChainRun,
-    Callbacks,
 )
 from langchain_core.exceptions import OutputParserException
 from langchain_core.language_models import BaseLanguageModel

libs/langchain/langchain/evaluation/comparison/eval_chain.py

@@ -6,7 +6,7 @@ import logging
 import re
 from typing import Any, Optional, Union
 
-from langchain_core.callbacks.manager import Callbacks
+from langchain_core.callbacks import Callbacks
 from langchain_core.language_models import BaseLanguageModel
 from langchain_core.output_parsers import BaseOutputParser
 from langchain_core.prompts.prompt import PromptTemplate

libs/langchain/langchain/evaluation/criteria/eval_chain.py

@@ -5,7 +5,7 @@ from collections.abc import Mapping
 from enum import Enum
 from typing import Any, Optional, Union
 
-from langchain_core.callbacks.manager import Callbacks
+from langchain_core.callbacks import Callbacks
 from langchain_core.language_models import BaseLanguageModel
 from langchain_core.output_parsers import BaseOutputParser
 from langchain_core.prompts import BasePromptTemplate

libs/langchain/langchain/evaluation/embedding_distance/base.py

@@ -6,10 +6,10 @@ from enum import Enum
 from importlib import util
 from typing import Any, Optional
 
+from langchain_core.callbacks import Callbacks
 from langchain_core.callbacks.manager import (
     AsyncCallbackManagerForChainRun,
     CallbackManagerForChainRun,
-    Callbacks,
 )
 from langchain_core.embeddings import Embeddings
 from langchain_core.utils import pre_init

libs/langchain/langchain/evaluation/qa/eval_chain.py

@@ -7,7 +7,7 @@ import string
 from collections.abc import Sequence
 from typing import Any, Optional
 
-from langchain_core.callbacks.manager import Callbacks
+from langchain_core.callbacks import Callbacks
 from langchain_core.language_models import BaseLanguageModel
 from langchain_core.prompts import PromptTemplate
 from pydantic import ConfigDict

libs/langchain/langchain/evaluation/scoring/eval_chain.py

@@ -6,7 +6,7 @@ import logging
 import re
 from typing import Any, Optional, Union
 
-from langchain_core.callbacks.manager import Callbacks
+from langchain_core.callbacks import Callbacks
 from langchain_core.language_models import BaseLanguageModel
 from langchain_core.output_parsers import BaseOutputParser
 from langchain_core.prompts.prompt import PromptTemplate

libs/langchain/langchain/evaluation/string_distance/base.py

@@ -3,10 +3,10 @@
 from enum import Enum
 from typing import Any, Callable, Optional
 
+from langchain_core.callbacks import Callbacks
 from langchain_core.callbacks.manager import (
     AsyncCallbackManagerForChainRun,
     CallbackManagerForChainRun,
-    Callbacks,
 )
 from langchain_core.utils import pre_init
 from pydantic import Field

libs/langchain/langchain/memory/buffer.py

@@ -1,10 +1,11 @@
 from typing import Any, Optional
 
 from langchain_core._api import deprecated
+from langchain_core.memory import BaseMemory
 from langchain_core.messages import BaseMessage, get_buffer_string
 from langchain_core.utils import pre_init
 
-from langchain.memory.chat_memory import BaseChatMemory, BaseMemory
+from langchain.memory.chat_memory import BaseChatMemory
 from langchain.memory.utils import get_prompt_input_key
 
 

libs/langchain/langchain/memory/vectorstore.py

@@ -5,10 +5,10 @@ from typing import Any, Optional, Union
 
 from langchain_core._api import deprecated
 from langchain_core.documents import Document
+from langchain_core.memory import BaseMemory
 from langchain_core.vectorstores import VectorStoreRetriever
 from pydantic import Field
 
-from langchain.memory.chat_memory import BaseMemory
 from langchain.memory.utils import get_prompt_input_key
 
 

libs/langchain/langchain/prompts/chat.py

@@ -2,7 +2,6 @@ from langchain_core.prompt_values import ChatPromptValue, ChatPromptValueConcret
 from langchain_core.prompts.chat import (
     AIMessagePromptTemplate,
     BaseChatPromptTemplate,
-    BaseMessagePromptTemplate,
     BaseStringMessagePromptTemplate,
     ChatMessagePromptTemplate,
     ChatPromptTemplate,
@@ -34,3 +33,5 @@ __all__ = [
     "MessageLike",
     "MessageLikeRepresentation",
 ]
+
+from langchain_core.prompts.message import BaseMessagePromptTemplate

libs/langchain/langchain/retrievers/contextual_compression.py

@@ -4,14 +4,10 @@ from langchain_core.callbacks import (
     AsyncCallbackManagerForRetrieverRun,
     CallbackManagerForRetrieverRun,
 )
-from langchain_core.documents import Document
+from langchain_core.documents import BaseDocumentCompressor, Document
 from langchain_core.retrievers import BaseRetriever, RetrieverLike
 from pydantic import ConfigDict
 
-from langchain.retrievers.document_compressors.base import (
-    BaseDocumentCompressor,
-)
-
 
 class ContextualCompressionRetriever(BaseRetriever):
     """Retriever that wraps a base retriever and compresses the results."""

libs/langchain/langchain/retrievers/document_compressors/__init__.py

@@ -34,9 +34,10 @@ def __getattr__(name: str) -> Any:
 __all__ = [
     "DocumentCompressorPipeline",
     "EmbeddingsFilter",
+    "FlashrankRerank",
     "LLMListwiseRerank",
     "LLMChainExtractor",
     "LLMChainFilter",
     "CohereRerank",
     "CrossEncoderReranker",
-] + list(_module_lookup.keys())
+]

libs/langchain/langchain/retrievers/document_compressors/base.py

@@ -2,7 +2,7 @@ from collections.abc import Sequence
 from inspect import signature
 from typing import Optional, Union
 
-from langchain_core.callbacks.manager import Callbacks
+from langchain_core.callbacks import Callbacks
 from langchain_core.documents import (
     BaseDocumentCompressor,
     BaseDocumentTransformer,

libs/langchain/langchain/retrievers/document_compressors/chain_extract.py

@@ -5,8 +5,8 @@ from __future__ import annotations
 from collections.abc import Sequence
 from typing import Any, Callable, Optional, cast
 
-from langchain_core.callbacks.manager import Callbacks
+from langchain_core.callbacks import Callbacks
-from langchain_core.documents import Document
+from langchain_core.documents import BaseDocumentCompressor, Document
 from langchain_core.language_models import BaseLanguageModel
 from langchain_core.output_parsers import BaseOutputParser, StrOutputParser
 from langchain_core.prompts import PromptTemplate
@@ -14,7 +14,6 @@ from langchain_core.runnables import Runnable
 from pydantic import ConfigDict
 
 from langchain.chains.llm import LLMChain
-from langchain.retrievers.document_compressors.base import BaseDocumentCompressor
 from langchain.retrievers.document_compressors.chain_extract_prompt import (
     prompt_template,
 )

libs/langchain/langchain/retrievers/document_compressors/chain_filter.py

@@ -3,8 +3,8 @@
 from collections.abc import Sequence
 from typing import Any, Callable, Optional
 
-from langchain_core.callbacks.manager import Callbacks
+from langchain_core.callbacks import Callbacks
-from langchain_core.documents import Document
+from langchain_core.documents import BaseDocumentCompressor, Document
 from langchain_core.language_models import BaseLanguageModel
 from langchain_core.output_parsers import StrOutputParser
 from langchain_core.prompts import BasePromptTemplate, PromptTemplate
@@ -14,7 +14,6 @@ from pydantic import ConfigDict
 
 from langchain.chains import LLMChain
 from langchain.output_parsers.boolean import BooleanOutputParser
-from langchain.retrievers.document_compressors.base import BaseDocumentCompressor
 from langchain.retrievers.document_compressors.chain_filter_prompt import (
     prompt_template,
 )

libs/langchain/langchain/retrievers/document_compressors/cohere_rerank.py

@@ -5,13 +5,11 @@ from copy import deepcopy
 from typing import Any, Optional, Union
 
 from langchain_core._api.deprecation import deprecated
-from langchain_core.callbacks.manager import Callbacks
+from langchain_core.callbacks import Callbacks
-from langchain_core.documents import Document
+from langchain_core.documents import BaseDocumentCompressor, Document
 from langchain_core.utils import get_from_dict_or_env
 from pydantic import ConfigDict, model_validator
 
-from langchain.retrievers.document_compressors.base import BaseDocumentCompressor
-
 
 @deprecated(
     since="0.0.30", removal="1.0", alternative_import="langchain_cohere.CohereRerank"

libs/langchain/langchain/retrievers/document_compressors/embeddings_filter.py

@@ -1,16 +1,12 @@
 from collections.abc import Sequence
 from typing import Callable, Optional
 
-from langchain_core.callbacks.manager import Callbacks
+from langchain_core.callbacks import Callbacks
-from langchain_core.documents import Document
+from langchain_core.documents import BaseDocumentCompressor, Document
 from langchain_core.embeddings import Embeddings
 from langchain_core.utils import pre_init
 from pydantic import ConfigDict, Field
 
-from langchain.retrievers.document_compressors.base import (
-    BaseDocumentCompressor,
-)
-
 
 def _get_similarity_function() -> Callable:
     try:

libs/langchain/langchain/runnables/hub.py

@@ -1,6 +1,7 @@
 from typing import Any, Optional
 
-from langchain_core.runnables.base import Input, Output, RunnableBindingBase
+from langchain_core.runnables.base import RunnableBindingBase
+from langchain_core.runnables.utils import Input, Output
 
 
 class HubRunnable(RunnableBindingBase[Input, Output]):

libs/langchain/langchain/schema/callbacks/tracers/base.py

@@ -1,3 +1,4 @@
-from langchain_core.tracers.base import BaseTracer, TracerException
+from langchain_core.exceptions import TracerException
+from langchain_core.tracers.base import BaseTracer
 
 __all__ = ["TracerException", "BaseTracer"]

libs/langchain/langchain/smith/evaluation/runner_utils.py

@@ -19,7 +19,7 @@ from typing import (
 )
 
 from langchain_core._api import warn_deprecated
-from langchain_core.callbacks.manager import Callbacks
+from langchain_core.callbacks import Callbacks
 from langchain_core.language_models import BaseLanguageModel
 from langchain_core.messages import BaseMessage, messages_from_dict
 from langchain_core.outputs import ChatResult, LLMResult
@@ -1226,7 +1226,7 @@ class _DatasetRunContainer:
 
 def _is_jupyter_environment() -> bool:
     try:
-        from IPython import get_ipython
+        from IPython.core.getipython import get_ipython
 
         res = get_ipython()
         return get_ipython() is not None and "zmqshell" in str(type(res))

libs/langchain/pyproject.toml

@@ -91,7 +91,7 @@ lint = [
     "cffi; python_version >= \"3.10\"",
 ]
 typing = [
-    "mypy<2.0,>=1.15",
+    "mypy<1.16,>=1.15",
     "types-pyyaml<7.0.0.0,>=6.0.12.2",
     "types-requests<3.0.0.0,>=2.28.11.5",
     "types-toml<1.0.0.0,>=0.10.8.1",
@@ -124,9 +124,18 @@ target-version = "py39"
 exclude = ["tests/integration_tests/examples/non-utf8-encoding.py"]
 
 [tool.mypy]
+strict = "True"
+strict_bytes = "True"
 ignore_missing_imports = "True"
-disallow_untyped_defs = "True"
+enable_error_code = "deprecated"
-warn_unused_ignores = "True"
+report_deprecated_as_note = "True"
+
+# TODO: activate for 'strict' checking
+disallow_untyped_calls = "False"
+disallow_any_generics = "False"
+disallow_untyped_decorators = "False"
+warn_return_any = "False"
+strict_equality = "False"
 
 [tool.codespell]
 skip = ".git,*.pdf,*.svg,*.pdf,*.yaml,*.ipynb,poetry.lock,*.min.js,*.css,package-lock.json,example_data,_dist,examples,*.trig"

libs/langchain/tests/unit_tests/callbacks/test_file.py

@@ -2,9 +2,10 @@ import pathlib
 from typing import Any, Optional
 
 import pytest
+from langchain_core.callbacks import CallbackManagerForChainRun
 
 from langchain.callbacks import FileCallbackHandler
-from langchain.chains.base import CallbackManagerForChainRun, Chain
+from langchain.chains.base import Chain
 
 
 class FakeChain(Chain):

libs/langchain/tests/unit_tests/callbacks/test_stdout.py

@@ -1,9 +1,10 @@
 from typing import Any, Optional
 
 import pytest
+from langchain_core.callbacks import CallbackManagerForChainRun
 
 from langchain.callbacks import StdOutCallbackHandler
-from langchain.chains.base import CallbackManagerForChainRun, Chain
+from langchain.chains.base import Chain
 
 
 class FakeChain(Chain):

libs/langchain/tests/unit_tests/evaluation/agents/test_eval_chain.py

@@ -3,9 +3,10 @@
 from typing import Any, Optional
 
 import pytest
-from langchain_core.agents import AgentAction, BaseMessage
+from langchain_core.agents import AgentAction
 from langchain_core.callbacks.manager import CallbackManagerForLLMRun
 from langchain_core.exceptions import OutputParserException
+from langchain_core.messages import BaseMessage
 from langchain_core.tools import tool
 from pydantic import Field
 

libs/langchain/tests/unit_tests/output_parsers/test_fix.py

@@ -4,12 +4,13 @@ from typing import Any, Callable, Optional, TypeVar
 import pytest
 from langchain_core.exceptions import OutputParserException
 from langchain_core.messages import AIMessage
+from langchain_core.output_parsers import BaseOutputParser
 from langchain_core.prompts.prompt import PromptTemplate
 from langchain_core.runnables import Runnable, RunnableLambda, RunnablePassthrough
 
 from langchain.output_parsers.boolean import BooleanOutputParser
 from langchain.output_parsers.datetime import DatetimeOutputParser
-from langchain.output_parsers.fix import BaseOutputParser, OutputFixingParser
+from langchain.output_parsers.fix import OutputFixingParser
 from langchain.output_parsers.prompts import NAIVE_FIX_PROMPT
 
 T = TypeVar("T")

libs/langchain/tests/unit_tests/output_parsers/test_retry.py

@@ -2,6 +2,8 @@ from datetime import datetime as dt
 from typing import Any, Callable, Optional, TypeVar
 
 import pytest
+from langchain_core.exceptions import OutputParserException
+from langchain_core.output_parsers import BaseOutputParser
 from langchain_core.prompt_values import PromptValue, StringPromptValue
 from langchain_core.runnables import Runnable, RunnableLambda, RunnablePassthrough
 
@@ -10,8 +12,6 @@ from langchain.output_parsers.datetime import DatetimeOutputParser
 from langchain.output_parsers.retry import (
     NAIVE_RETRY_PROMPT,
     NAIVE_RETRY_WITH_ERROR_PROMPT,
-    BaseOutputParser,
-    OutputParserException,
     RetryOutputParser,
     RetryWithErrorOutputParser,
 )

libs/langchain/tests/unit_tests/retrievers/sequential_retriever.py

@@ -1,4 +1,5 @@
-from langchain_core.retrievers import BaseRetriever, Document
+from langchain_core.documents import Document
+from langchain_core.retrievers import BaseRetriever
 
 
 class SequentialRetriever(BaseRetriever):

libs/langchain/tests/unit_tests/runnables/test_hub.py

@@ -2,7 +2,7 @@ from typing import Any
 from unittest.mock import Mock, patch
 
 from langchain_core.prompts import ChatPromptTemplate
-from langchain_core.runnables.base import ConfigurableField
+from langchain_core.runnables import ConfigurableField
 
 from langchain.runnables.hub import HubRunnable
 

libs/langchain/tests/unit_tests/runnables/test_openai_functions.py

@@ -5,7 +5,7 @@ from langchain_core.language_models.chat_models import BaseChatModel
 from langchain_core.messages import AIMessage, BaseMessage
 from langchain_core.outputs import ChatGeneration, ChatResult
 from pytest_mock import MockerFixture
-from syrupy import SnapshotAssertion
+from syrupy.assertion import SnapshotAssertion
 
 from langchain.runnables.openai_functions import OpenAIFunctionsRouter
 

libs/langchain/uv.lock

@@ -2566,7 +2566,7 @@ test-integration = [
 typing = [
     { name = "langchain-core", editable = "../core" },
     { name = "langchain-text-splitters", editable = "../text-splitters" },
-    { name = "mypy", specifier = ">=1.15,<2.0" },
+    { name = "mypy", specifier = ">=1.15,<1.16" },
     { name = "mypy-protobuf", specifier = ">=3.0.0,<4.0.0" },
     { name = "numpy", marker = "python_full_version < '3.13'", specifier = ">=1.26.4" },
     { name = "numpy", marker = "python_full_version >= '3.13'", specifier = ">=2.1.0" },