From d455bd841d43561ecf99d1ca553ce0cb66cdea82 Mon Sep 17 00:00:00 2001 From: Michael Li Date: Fri, 7 Nov 2025 23:54:22 +1100 Subject: [PATCH] fix: fix previoius edge cases such as 0 (#6379) Thank you for contributing to LangGraph! 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.** - [x] **PR title**: Follows the format: {TYPE}({SCOPE}): {DESCRIPTION} - Examples: - feat(core): add multi-tenant support - fix(cli): resolve flag parsing error - docs(openai): update API usage examples - Allowed `{TYPE}` values: - feat, fix, docs, style, refactor, perf, test, build, ci, chore, revert, release - Allowed `{SCOPE}` values (optional): - langgraph, docs, cli, checkpoint, checkpoint-postgres, checkpoint-sqlite, prebuilt, scheduler-kafka, sdk-py - Once you've written the title, please delete this checklist item; do not include it in the PR. - [x] **PR message**: ***Delete this entire checklist*** and replace with - **Description:** a description of the change. Include a [closing keyword](https://docs.github.com/en/issues/tracking-your-work-with-issues/using-issues/linking-a-pull-request-to-an-issue#linking-a-pull-request-to-an-issue-using-a-keyword) if applicable. - **Issue:** the issue # it fixes, if applicable - **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! - [x] **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. - [x] **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://github.com/langchain-ai/langgraph/blob/main/CONTRIBUTING.md) 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. --- libs/langgraph/langgraph/runtime.py | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/libs/langgraph/langgraph/runtime.py b/libs/langgraph/langgraph/runtime.py index 25fcecb53..0f23ec69a 100644 --- a/libs/langgraph/langgraph/runtime.py +++ b/libs/langgraph/langgraph/runtime.py @@ -111,7 +111,7 @@ class Runtime(Generic[ContextT]): stream_writer=other.stream_writer if other.stream_writer is not _no_op_stream_writer else self.stream_writer, - previous=other.previous or self.previous, + previous=self.previous if other.previous is None else other.previous, ) def override(