Remove redundant/outdated `@pytest.mark.requires("jinja2")` decorator
Pytest marks (like `@pytest.mark.requires(...)`) applied directly to
fixtures have no effect and are deprecated.
Excluded pydantic_v1 module from import testing
Acceptable since this pydantic_v1 is explicitly deprecated. Testing its
importability at this stage serves little purpose since users should
migrate away from it.
## Summary
Adds test coverage for the `stringify_value` utility function to handle
complex nested data structures that weren't previously tested.
## Changes
- Added `test_stringify_value_nested_structures()` to `test_strings.py`
- Tests nested dictionaries within lists
- Tests mixed-type lists with various data types
- Verifies proper stringification of complex nested structures
## Why This Matters
- Fills a gap in test coverage for edge cases
- Ensures `stringify_value` handles complex data structures correctly
- Improves confidence in string utility functions used throughout the
codebase
- Low risk addition that strengthens existing test suite
## Testing
```bash
uv run --group test pytest libs/core/tests/unit_tests/utils/test_strings.py::test_stringify_value_nested_structures -v
```
This test addition follows the project's testing patterns and adds
meaningful coverage without introducing any breaking changes.
---------
Co-authored-by: Mason Daugherty <mason@langchain.dev>
### Description
* Replace the Mermaid graph node label escaping logic
(`_escape_node_label`) with `_to_safe_id`, which converts a string into
a unique, Mermaid-compatible node id. Ensures nodes with special
characters always render correctly.
**Before**
* Invalid characters (e.g. `开`) replaced with `_`. Causes collisions
between nodes with names that are the same length and contain all
non-safe characters:
```python
_escape_node_label("开") # '_'
_escape_node_label("始") # '_' same as above, but different character passed in. not a unique mapping.
```
**After**
```python
_to_safe_id("开") # \5f00
_to_safe_id("始") # \59cb unique!
```
### Tests
* Rename `test_graph_mermaid_escape_node_label()` to
`test_graph_mermaid_to_safe_id()` and update function logic to use
`_to_safe_id`
* Add `test_graph_mermaid_special_chars()`
### Issue
Fixeslangchain-ai/langgraph#6036
Description: Fixes a bug in RunnableRetry where .batch / .abatch could
return misordered outputs (e.g. inputs [0,1,2] yielding [1,1,2]) when
some items succeeded on an earlier attempt and others were retried. Root
cause: successful results were stored keyed by the index within the
shrinking “pending” subset rather than the original input index, causing
collisions and reordered/duplicated outputs after retries. Fix updates
_batch and _abatch to:
- Track remaining original indices explicitly.
- Call underlying batch/abatch only on remaining inputs.
- Map results back to original indices.
- Preserve final ordering by reconstructing outputs in original
positional order.
Issue: Fixes#21326
Tests:
- Added regression tests: test_retry_batch_preserves_order and
test_async_retry_batch_preserves_order asserting correct ordering after
a single controlled failure + retry.
- Existing retry tests still pass.
Dependencies:
- None added or changed.
---------
Co-authored-by: Eugene Yurtsev <eyurtsev@gmail.com>
**Description:** Fixes infinite recursion issue in JSON schema
dereferencing when objects contain both $ref and other properties (e.g.,
nullable, description, additionalProperties). This was causing Apollo
MCP server schemas to hang indefinitely during tool binding.
**Problem:**
- Commit fb5da8384 changed the condition from `set(obj.keys()) ==
{"$ref"}` to `"$ref" in set(obj.keys())`
- This caused objects with $ref + other properties to be treated as pure
$ref nodes
- Result: other properties were lost and infinite recursion occurred
with complex schemas
**Solution:**
- Restore pure $ref detection for objects with only $ref key
- Add proper handling for mixed $ref objects that preserves all
properties
- Merge resolved reference content with other properties
- Maintain cycle detection to prevent infinite recursion
**Impact:**
- Fixes Apollo MCP server schema integration
- Resolves tool binding infinite recursion with complex GraphQL schemas
- Preserves backward compatibility with existing functionality
- No performance impact - actually improves handling of complex schemas
**Issue:** Fixes#32511
**Dependencies:** None
**Testing:**
- Added comprehensive unit tests covering mixed $ref scenarios
- All existing tests pass (1326 passed, 0 failed)
- Tested with realistic Apollo GraphQL schemas
- Stress tested with 100 iterations of complex schemas
**Verification:**
- ✅ `make format` - All files properly formatted
- ✅ `make lint` - All linting checks pass
- ✅ `make test` - All 1326 unit tests pass
- ✅ No breaking changes - full backwards compatibility maintained
---------
Co-authored-by: Marcus <marcus@Marcus-M4-MAX.local>
Co-authored-by: Eugene Yurtsev <eyurtsev@gmail.com>
# Description
This PR fixes a bug in _recursive_set_additional_properties_false used
in function_calling.convert_to_openai_function.
Previously, schemas with "additionalProperties=True" were not correctly
overridden when strict validation was expected, which could lead to
invalid OpenAI function schemas.
The updated implementation ensures that:
- Any schema with "additionalProperties" already set will now be forced
to False under strict mode.
- Recursive traversal of properties, items, and anyOf is preserved.
- Function signature remains unchanged for backward compatibility.
# Issue
When using tool calling in OpenAI structured output strict mode
(strict=True), 400: "Invalid schema for response_format XXXXX
'additionalProperties' is required to be supplied and to be false" error
raises for the parameter that contains dict type. OpenAI requires
additionalProperties to be set to False.
Some PRs try to resolved the issue.
- PR #25169 introduced _recursive_set_additional_properties_false to
recursively set additionalProperties=False.
- PR #26287 fixed handling of empty parameter tools for OpenAI function
generation.
- PR #30971 added support for Union type arguments in strict mode of
OpenAI function calling / structured output.
Despite these improvements, since Pydantic 2.11, it will always add
`additionalProperties: True` for arbitrary dictionary schemas dict or
Any (https://pydantic.dev/articles/pydantic-v2-11-release#changes).
Schemas that already had additionalProperties=True in such cases were
not being overridden, which this PR addresses to ensure strict mode
behaves correctly in all cases.
# Dependencies
No Changes
---------
Co-authored-by: Zhong, Yu <yzhong@freewheel.com>
**Description:**
Raise a more descriptive OutputParserException when JSON parsing results
in a non-dict type. This improves debugging and aligns behavior with
expectations when using expected_keys.
**Issue:**
Fixes#32233
**Twitter handle:**
@yashvtobre
**Testing:**
- Ran make format and make lint from the root directory; both passed
cleanly.
- Attempted make test but no such target exists in the root Makefile.
- Executed tests directly via pytest targeting the relevant test file,
confirming all tests pass except for unrelated async test failures
outside the scope of this change.
**Notes:**
- No additional dependencies introduced.
- Changes are backward compatible and isolated within the output parser
module.
---------
Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>
Co-authored-by: Mason Daugherty <mason@langchain.dev>
Co-authored-by: Mason Daugherty <github@mdrxy.com>
- **Description:** Currently,
`langchain_core.runnables.graph_mermaid.py` is hardcoded to use
mermaid.ink to render graph diagrams. It would be nice to allow users to
specify a custom URL, e.g. for self-hosted instances of the Mermaid
server.
- **Issue:** [Langchain Forum: allow custom mermaid API
URL](https://forum.langchain.com/t/feature-request-allow-custom-mermaid-api-url/1472)
- **Dependencies:** None
- [X] **Add tests and docs**: Added unit tests using mock requests.
- [X] **Lint and test**: Run `make format`, `make lint` and `make test`.
Minimal example using the feature:
```python
import os
import operator
from pathlib import Path
from typing import Any, Annotated, TypedDict
from langgraph.graph import StateGraph
class State(TypedDict):
messages: Annotated[list[dict[str, Any]], operator.add]
def hello_node(state: State) -> State:
return {"messages": [{"role": "assistant", "content": "pong!"}]}
builder = StateGraph(State)
builder.add_node("hello_node", hello_node)
builder.add_edge("__start__", "hello_node")
builder.add_edge("hello_node", "__end__")
graph = builder.compile()
# Run graph
output = graph.invoke({"messages": [{"role": "user", "content": "ping?"}]})
# Draw graph
Path("graph.png").write_bytes(graph.get_graph().draw_mermaid_png(base_url="https://custom-mermaid.ink"))
```
---------
Co-authored-by: Eugene Yurtsev <eyurtsev@gmail.com>
This pull request introduces a failing unit test to reproduce the bug
reported in issue #32028.
The test asserts the expected behavior: `BaseCallbackManager.merge()`
should combine `handlers` and `inheritable_handlers` independently,
without mixing them. This test will fail on the current codebase and is
intended to guide the fix and prevent future regressions.
---------
Co-authored-by: Eugene Yurtsev <eyurtsev@gmail.com>
Co-authored-by: Mason Daugherty <mason@langchain.dev>
This is better than using a subclass as returning a `property` works
with `ClassWithBetaMethods.beta_property.__doc__`
Co-authored-by: Mason Daugherty <mason@langchain.dev>
Added an id field to the Document passed to filter for
InMemoryVectorStore similarity search. This allows filtering by Document
id and brings the input to the filter in line with the result returned
by the vector similarity search.
---------
Co-authored-by: Eugene Yurtsev <eyurtsev@gmail.com>
Supersedes #32408
Description:
This PR ensures that tool calls without explicitly provided `args` will
default to an empty dictionary (`{}`), allowing tools with no parameters
(e.g. `def foo() -> str`) to be registered and invoked without
validation errors. This change improves compatibility with agent
frameworks that may omit the `args` field when generating tool calls.
Issue:
See
[langgraph#5722](https://github.com/langchain-ai/langgraph/issues/5722)
–
LangGraph currently emits tool calls without `args`, which leads to
validation errors
when tools with no parameters are invoked. This PR ensures compatibility
by defaulting
`args` to `{}` when missing.
Dependencies:
None
---------
Thank you for contributing to LangChain! Follow these steps to mark your
pull request as ready for review. **If any of these steps are not
completed, your PR will not be considered for review.**
- [ ] **PR title**: Follows the format: {TYPE}({SCOPE}): {DESCRIPTION}
- Examples:
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- fix(cli): resolve flag parsing error
- docs(openai): update API usage examples
- Allowed `{TYPE}` values:
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- Allowed `{SCOPE}` values (optional):
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- Note: the `{DESCRIPTION}` must not start with an uppercase letter.
- Once you've written the title, please delete this checklist item; do
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- **Description:** a description of the change. Include a [closing
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if applicable to a relevant issue.
- **Issue:** the issue # it fixes, if applicable (e.g. Fixes#123)
- **Dependencies:** any dependencies required for this change
- **Twitter handle:** if your PR gets announced, and you'd like a
mention, we'll gladly shout you out!
- [ ] **Add tests and docs**: If you're adding a new integration, you
must include:
1. A test for the integration, preferably unit tests that do not rely on
network access,
2. An example notebook showing its use. It lives in
`docs/docs/integrations` directory.
- [ ] **Lint and test**: Run `make format`, `make lint` and `make test`
from the root of the package(s) you've modified. **We will not consider
a PR unless these three are passing in CI.** See [contribution
guidelines](https://python.langchain.com/docs/contributing/) for more.
Additional guidelines:
- Make sure optional dependencies are imported within a function.
- Please do not add dependencies to `pyproject.toml` files (even
optional ones) unless they are **required** for unit tests.
- Most PRs should not touch more than one package.
- Changes should be backwards compatible.
---------
Signed-off-by: jitokim <pigberger70@gmail.com>
Co-authored-by: jito <pigberger70@gmail.com>
Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>
**Description:** fix an issue I discovered when attempting to merge
messages in which one message has an `index` key in its content
dictionary and another does not.
Fixes a streaming bug where models like Qwen3 (using OpenAI interface)
send tool call chunks with inconsistent indices, resulting in
duplicate/erroneous tool calls instead of a single merged tool call.
## Problem
When Qwen3 streams tool calls, it sends chunks with inconsistent `index`
values:
- First chunk: `index=1` with tool name and partial arguments
- Subsequent chunks: `index=0` with `name=None`, `id=None` and argument
continuation
The existing `merge_lists` function only merges chunks when their
`index` values match exactly, causing these logically related chunks to
remain separate, resulting in multiple incomplete tool calls instead of
one complete tool call.
```python
# Before fix: Results in 1 valid + 1 invalid tool call
chunk1 = AIMessageChunk(tool_call_chunks=[
{"name": "search", "args": '{"query":', "id": "call_123", "index": 1}
])
chunk2 = AIMessageChunk(tool_call_chunks=[
{"name": None, "args": ' "test"}', "id": None, "index": 0}
])
merged = chunk1 + chunk2 # Creates 2 separate tool calls
# After fix: Results in 1 complete tool call
merged = chunk1 + chunk2 # Creates 1 merged tool call: search({"query": "test"})
```
## Solution
Enhanced the `merge_lists` function in `langchain_core/utils/_merge.py`
with intelligent tool call chunk merging:
1. **Preserves existing behavior**: Same-index chunks still merge as
before
2. **Adds special handling**: Tool call chunks with
`name=None`/`id=None` that don't match any existing index are now merged
with the most recent complete tool call chunk
3. **Maintains backward compatibility**: All existing functionality
works unchanged
4. **Targeted fix**: Only affects tool call chunks, doesn't change
behavior for other list items
The fix specifically handles the pattern where:
- A continuation chunk has `name=None` and `id=None` (indicating it's
part of an ongoing tool call)
- No matching index is found in existing chunks
- There exists a recent tool call chunk with a valid name or ID to merge
with
## Testing
Added comprehensive test coverage including:
- ✅ Qwen3-style chunks with different indices now merge correctly
- ✅ Existing same-index behavior preserved
- ✅ Multiple distinct tool calls remain separate
- ✅ Edge cases handled (empty chunks, orphaned continuations)
- ✅ Backward compatibility maintained
Fixes#31511.
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---------
Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: mdrxy <61371264+mdrxy@users.noreply.github.com>
Co-authored-by: Mason Daugherty <github@mdrxy.com>
Co-authored-by: Mason Daugherty <mason@langchain.dev>
