REFACTOR: Refactor langchain_core (#13627)

Changes:
- remove langchain_core/schema since no clear distinction b/n schema and
non-schema modules
- make every module that doesn't end in -y plural
- where easy have 1-2 classes per file
- no more than one level of nesting in directories
- only import from top level core modules in langchain

libs/core/tests/unit_tests/_api/test_imports.py

@@ -6,6 +6,8 @@ EXPECTED_ALL = [
     "suppress_langchain_deprecation_warning",
     "surface_langchain_deprecation_warnings",
     "warn_deprecated",
+    "as_import_path",
+    "get_relative_path",
 ]
 
 

libs/core/tests/unit_tests/example_selectors/test_length_based_example_selector.py

@@ -1,10 +1,10 @@
 """Test functionality related to length based selector."""
 import pytest
 
-from langchain_core.prompts.example_selector.length_based import (
+from langchain_core.example_selectors import (
     LengthBasedExampleSelector,
 )
-from langchain_core.prompts.prompt import PromptTemplate
+from langchain_core.prompts import PromptTemplate
 
 EXAMPLES = [
     {"question": "Question: who are you?\nAnswer: foo"},

libs/core/tests/unit_tests/fake/callbacks.py

@@ -4,8 +4,8 @@ from typing import Any, Dict, List, Optional, Union
 from uuid import UUID
 
 from langchain_core.callbacks.base import AsyncCallbackHandler, BaseCallbackHandler
+from langchain_core.messages import BaseMessage
 from langchain_core.pydantic_v1 import BaseModel
-from langchain_core.schema.messages import BaseMessage
 
 
 class BaseFakeCallbackHandler(BaseModel):

libs/core/tests/unit_tests/fake/chat_model.py

@@ -7,10 +7,9 @@ from langchain_core.callbacks.manager import (
     AsyncCallbackManagerForLLMRun,
     CallbackManagerForLLMRun,
 )
-from langchain_core.chat_model import BaseChatModel, SimpleChatModel
-from langchain_core.schema import ChatResult
-from langchain_core.schema.messages import AIMessageChunk, BaseMessage
-from langchain_core.schema.output import ChatGeneration, ChatGenerationChunk
+from langchain_core.language_models.chat_models import BaseChatModel, SimpleChatModel
+from langchain_core.messages import AIMessageChunk, BaseMessage
+from langchain_core.outputs import ChatGeneration, ChatGenerationChunk, ChatResult
 
 
 class FakeMessagesListChatModel(BaseChatModel):

libs/core/tests/unit_tests/fake/llm.py

@@ -6,9 +6,8 @@ from langchain_core.callbacks.manager import (
     AsyncCallbackManagerForLLMRun,
     CallbackManagerForLLMRun,
 )
-from langchain_core.llm import LLM
+from langchain_core.language_models import LLM, LanguageModelInput
 from langchain_core.runnables import RunnableConfig
-from langchain_core.schema.language_model import LanguageModelInput
 
 
 class FakeListLLM(LLM):

libs/core/tests/unit_tests/fake/memory.py

@@ -1,10 +1,10 @@
 from typing import List
 
-from langchain_core.pydantic_v1 import BaseModel, Field
-from langchain_core.schema import (
+from langchain_core.chat_history import (
     BaseChatMessageHistory,
 )
-from langchain_core.schema.messages import BaseMessage
+from langchain_core.messages import BaseMessage
+from langchain_core.pydantic_v1 import BaseModel, Field
 
 
 class ChatMessageHistory(BaseChatMessageHistory, BaseModel):

libs/core/tests/unit_tests/prompts/test_chat.py

@@ -3,6 +3,13 @@ from typing import Any, List, Union
 
 import pytest
 
+from langchain_core.messages import (
+    AIMessage,
+    BaseMessage,
+    HumanMessage,
+    SystemMessage,
+    get_buffer_string,
+)
 from langchain_core.prompts import PromptTemplate
 from langchain_core.prompts.chat import (
     AIMessagePromptTemplate,
@@ -15,13 +22,6 @@ from langchain_core.prompts.chat import (
     SystemMessagePromptTemplate,
     _convert_to_message,
 )
-from langchain_core.schema.messages import (
-    AIMessage,
-    BaseMessage,
-    HumanMessage,
-    SystemMessage,
-    get_buffer_string,
-)
 
 
 def create_messages() -> List[BaseMessagePromptTemplate]:

libs/core/tests/unit_tests/prompts/test_few_shot.py

@@ -3,19 +3,19 @@ from typing import Any, Dict, List, Sequence, Tuple
 
 import pytest
 
+from langchain_core.example_selectors import BaseExampleSelector
+from langchain_core.messages import AIMessage, HumanMessage, SystemMessage
 from langchain_core.prompts import (
     AIMessagePromptTemplate,
     ChatPromptTemplate,
     HumanMessagePromptTemplate,
 )
 from langchain_core.prompts.chat import SystemMessagePromptTemplate
-from langchain_core.prompts.example_selector.base import BaseExampleSelector
 from langchain_core.prompts.few_shot import (
     FewShotChatMessagePromptTemplate,
     FewShotPromptTemplate,
 )
 from langchain_core.prompts.prompt import PromptTemplate
-from langchain_core.schema import AIMessage, HumanMessage, SystemMessage
 
 EXAMPLE_PROMPT = PromptTemplate(
     input_variables=["question", "answer"], template="{question}: {answer}"

libs/core/tests/unit_tests/prompts/test_imports.py

@@ -6,20 +6,22 @@ EXPECTED_ALL = [
     "BasePromptTemplate",
     "ChatMessagePromptTemplate",
     "ChatPromptTemplate",
+    "ChatPromptValueConcrete",
     "FewShotPromptTemplate",
     "FewShotPromptWithTemplates",
+    "FewShotChatMessagePromptTemplate",
+    "format_document",
+    "ChatPromptValue",
+    "PromptValue",
+    "StringPromptValue",
     "HumanMessagePromptTemplate",
-    "LengthBasedExampleSelector",
-    "MaxMarginalRelevanceExampleSelector",
     "MessagesPlaceholder",
     "PipelinePromptTemplate",
     "Prompt",
     "PromptTemplate",
-    "SemanticSimilarityExampleSelector",
     "StringPromptTemplate",
     "SystemMessagePromptTemplate",
     "load_prompt",
-    "FewShotChatMessagePromptTemplate",
 ]
 
 

libs/core/tests/unit_tests/prompts/test_utils.py

@@ -1,5 +1,5 @@
 """Test functionality related to prompt utils."""
-from langchain_core.prompts.example_selector.semantic_similarity import sorted_values
+from langchain_core.example_selectors import sorted_values
 
 
 def test_sorted_vals() -> None:

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

@@ -1,8 +1,8 @@
 from langchain_core.callbacks.manager import CallbackManager
 from langchain_core.callbacks.stdout import StdOutCallbackHandler
 from langchain_core.callbacks.streaming_stdout import StreamingStdOutCallbackHandler
-from langchain_core.callbacks.tracers.stdout import ConsoleCallbackHandler
 from langchain_core.runnables.config import RunnableConfig, merge_configs
+from langchain_core.tracers.stdout import ConsoleCallbackHandler
 
 
 def test_merge_config_callbacks() -> None:

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

@@ -1,9 +1,10 @@
 from typing import Any, Callable, Sequence, Union
 
+from langchain_core.messages import AIMessage, BaseMessage, HumanMessage
 from langchain_core.pydantic_v1 import BaseModel
-from langchain_core.runnables import RunnableConfig, RunnableLambda
+from langchain_core.runnables.base import RunnableLambda
+from langchain_core.runnables.config import RunnableConfig
 from langchain_core.runnables.history import RunnableWithMessageHistory
-from langchain_core.schema import AIMessage, BaseMessage, HumanMessage
 from tests.unit_tests.fake.memory import ChatMessageHistory
 
 

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

@@ -26,53 +26,55 @@ from langchain_core.callbacks.manager import (
     collect_runs,
     trace_as_chain_group,
 )
-from langchain_core.callbacks.tracers.base import BaseTracer
-from langchain_core.callbacks.tracers.log_stream import RunLog, RunLogPatch
-from langchain_core.callbacks.tracers.schemas import Run
-from langchain_core.callbacks.tracers.stdout import ConsoleCallbackHandler
-from langchain_core.load.dump import dumpd, dumps
-from langchain_core.output_parsers.list import CommaSeparatedListOutputParser
-from langchain_core.prompts import PromptTemplate
-from langchain_core.prompts.base import StringPromptValue
-from langchain_core.prompts.chat import (
-    ChatPromptTemplate,
-    ChatPromptValue,
-    HumanMessagePromptTemplate,
-    MessagesPlaceholder,
-    SystemMessagePromptTemplate,
-)
-from langchain_core.pydantic_v1 import BaseModel
-from langchain_core.runnables import (
-    RouterRunnable,
-    Runnable,
-    RunnableBranch,
-    RunnableConfig,
-    RunnableLambda,
-    RunnableParallel,
-    RunnablePassthrough,
-    RunnableSequence,
-    RunnableWithFallbacks,
-)
-from langchain_core.runnables.base import (
-    ConfigurableField,
-    RunnableBinding,
-    RunnableGenerator,
-)
-from langchain_core.runnables.utils import (
-    ConfigurableFieldMultiOption,
-    ConfigurableFieldSingleOption,
-    add,
-)
-from langchain_core.schema.document import Document
-from langchain_core.schema.messages import (
+from langchain_core.documents import Document
+from langchain_core.load import dumpd, dumps
+from langchain_core.messages import (
     AIMessage,
     AIMessageChunk,
     HumanMessage,
     SystemMessage,
 )
-from langchain_core.schema.output_parser import BaseOutputParser, StrOutputParser
-from langchain_core.schema.retriever import BaseRetriever
-from langchain_core.tool import BaseTool, tool
+from langchain_core.output_parsers import (
+    BaseOutputParser,
+    CommaSeparatedListOutputParser,
+    StrOutputParser,
+)
+from langchain_core.prompts import (
+    ChatPromptTemplate,
+    ChatPromptValue,
+    HumanMessagePromptTemplate,
+    MessagesPlaceholder,
+    PromptTemplate,
+    StringPromptValue,
+    SystemMessagePromptTemplate,
+)
+from langchain_core.pydantic_v1 import BaseModel
+from langchain_core.retrievers import BaseRetriever
+from langchain_core.runnables import (
+    ConfigurableField,
+    ConfigurableFieldMultiOption,
+    ConfigurableFieldSingleOption,
+    RouterRunnable,
+    Runnable,
+    RunnableBinding,
+    RunnableBranch,
+    RunnableConfig,
+    RunnableGenerator,
+    RunnableLambda,
+    RunnableParallel,
+    RunnablePassthrough,
+    RunnableSequence,
+    RunnableWithFallbacks,
+    add,
+)
+from langchain_core.tools import BaseTool, tool
+from langchain_core.tracers import (
+    BaseTracer,
+    ConsoleCallbackHandler,
+    Run,
+    RunLog,
+    RunLogPatch,
+)
 from tests.unit_tests.fake.chat_model import FakeListChatModel
 from tests.unit_tests.fake.llm import FakeListLLM, FakeStreamingListLLM
 
@@ -1539,7 +1541,7 @@ def test_with_listeners(mocker: MockerFixture) -> None:
     )
     chat = FakeListChatModel(responses=["foo"])
 
-    chain = prompt | chat
+    chain: Runnable = prompt | chat
 
     mock_start = mocker.Mock()
     mock_end = mocker.Mock()
@@ -1572,7 +1574,7 @@ async def test_with_listeners_async(mocker: MockerFixture) -> None:
     )
     chat = FakeListChatModel(responses=["foo"])
 
-    chain = prompt | chat
+    chain: Runnable = prompt | chat
 
     mock_start = mocker.Mock()
     mock_end = mocker.Mock()
@@ -1608,7 +1610,7 @@ def test_prompt_with_chat_model(
     )
     chat = FakeListChatModel(responses=["foo"])
 
-    chain = prompt | chat
+    chain: Runnable = prompt | chat
 
     assert repr(chain) == snapshot
     assert isinstance(chain, RunnableSequence)
@@ -1712,7 +1714,7 @@ async def test_prompt_with_chat_model_async(
     )
     chat = FakeListChatModel(responses=["foo"])
 
-    chain = prompt | chat
+    chain: Runnable = prompt | chat
 
     assert repr(chain) == snapshot
     assert isinstance(chain, RunnableSequence)
@@ -1819,7 +1821,7 @@ async def test_prompt_with_llm(
     )
     llm = FakeListLLM(responses=["foo", "bar"])
 
-    chain = prompt | llm
+    chain: Runnable = prompt | llm
 
     assert isinstance(chain, RunnableSequence)
     assert chain.first == prompt
@@ -2325,13 +2327,13 @@ def test_seq_prompt_dict(mocker: MockerFixture, snapshot: SnapshotAssertion) ->
 async def test_router_runnable(
     mocker: MockerFixture, snapshot: SnapshotAssertion
 ) -> None:
-    chain1 = ChatPromptTemplate.from_template(
+    chain1: Runnable = ChatPromptTemplate.from_template(
         "You are a math genius. Answer the question: {question}"
     ) | FakeListLLM(responses=["4"])
-    chain2 = ChatPromptTemplate.from_template(
+    chain2: Runnable = ChatPromptTemplate.from_template(
         "You are an english major. Answer the question: {question}"
     ) | FakeListLLM(responses=["2"])
-    router = RouterRunnable({"math": chain1, "english": chain2})
+    router: Runnable = RouterRunnable({"math": chain1, "english": chain2})
     chain: Runnable = {
         "key": lambda x: x["key"],
         "input": {"question": lambda x: x["question"]},
@@ -2377,10 +2379,10 @@ async def test_router_runnable(
 async def test_higher_order_lambda_runnable(
     mocker: MockerFixture, snapshot: SnapshotAssertion
 ) -> None:
-    math_chain = ChatPromptTemplate.from_template(
+    math_chain: Runnable = ChatPromptTemplate.from_template(
         "You are a math genius. Answer the question: {question}"
     ) | FakeListLLM(responses=["4"])
-    english_chain = ChatPromptTemplate.from_template(
+    english_chain: Runnable = ChatPromptTemplate.from_template(
         "You are an english major. Answer the question: {question}"
     ) | FakeListLLM(responses=["2"])
     input_map: Runnable = RunnableParallel(
@@ -3096,7 +3098,7 @@ async def test_deep_astream_assign() -> None:
 def test_runnable_sequence_transform() -> None:
     llm = FakeStreamingListLLM(responses=["foo-lish"])
 
-    chain = llm | StrOutputParser()
+    chain: Runnable = llm | StrOutputParser()
 
     stream = chain.transform(llm.stream("Hi there!"))
 
@@ -3111,7 +3113,7 @@ def test_runnable_sequence_transform() -> None:
 async def test_runnable_sequence_atransform() -> None:
     llm = FakeStreamingListLLM(responses=["foo-lish"])
 
-    chain = llm | StrOutputParser()
+    chain: Runnable = llm | StrOutputParser()
 
     stream = chain.atransform(llm.astream("Hi there!"))
 

libs/core/tests/unit_tests/schema/test_imports.py

@@ -1,43 +0,0 @@
-from langchain_core.schema import __all__
-
-EXPECTED_ALL = [
-    "BaseCache",
-    "BaseMemory",
-    "BaseStore",
-    "AgentFinish",
-    "AgentAction",
-    "Document",
-    "BaseChatMessageHistory",
-    "BaseDocumentTransformer",
-    "BaseMessage",
-    "ChatMessage",
-    "FunctionMessage",
-    "HumanMessage",
-    "AIMessage",
-    "SystemMessage",
-    "messages_from_dict",
-    "messages_to_dict",
-    "_message_to_dict",
-    "_message_from_dict",
-    "get_buffer_string",
-    "RunInfo",
-    "LLMResult",
-    "ChatResult",
-    "ChatGeneration",
-    "Generation",
-    "PromptValue",
-    "LangChainException",
-    "BaseRetriever",
-    "RUN_KEY",
-    "Memory",
-    "OutputParserException",
-    "StrOutputParser",
-    "BaseOutputParser",
-    "BaseLLMOutputParser",
-    "BasePromptTemplate",
-    "format_document",
-]
-
-
-def test_all_imports() -> None:
-    assert set(__all__) == set(EXPECTED_ALL)

libs/core/tests/unit_tests/test_messages.py

@@ -1,6 +1,6 @@
 import pytest
 
-from langchain_core.schema.messages import (
+from langchain_core.messages import (
     AIMessageChunk,
     ChatMessageChunk,
     FunctionMessageChunk,

libs/core/tests/unit_tests/test_outputs.py

@@ -1,5 +1,5 @@
-from langchain_core.schema.messages import HumanMessageChunk
-from langchain_core.schema.output import ChatGenerationChunk, GenerationChunk
+from langchain_core.messages import HumanMessageChunk
+from langchain_core.outputs import ChatGenerationChunk, GenerationChunk
 
 
 def test_generation_chunk() -> None:

libs/core/tests/unit_tests/test_tools.py

@@ -7,12 +7,12 @@ from typing import Any, List, Optional, Type, Union
 
 import pytest
 
-from langchain_core.callbacks.manager import (
+from langchain_core.callbacks import (
     AsyncCallbackManagerForToolRun,
     CallbackManagerForToolRun,
 )
 from langchain_core.pydantic_v1 import BaseModel
-from langchain_core.tool import (
+from langchain_core.tools import (
     BaseTool,
     SchemaAnnotationError,
     StructuredTool,

libs/core/tests/unit_tests/utils/test_imports.py

@@ -14,6 +14,7 @@ EXPECTED_ALL = [
     "print_text",
     "raise_for_status_with_text",
     "xor_args",
+    "try_load_from_hub",
 ]