CI lint jobs use `uv run --all-groups` for all tools, but ruff doesn't
need dependency resolution — only mypy does. By splitting into
`UV_RUN_LINT` (ruff) and `UV_RUN_TYPE` (mypy), the CI-facing targets run
ruff with `--group lint` only, giving fast-fail feedback before mypy
triggers the full environment sync.
For packages where source code only conditionally imports heavy deps
(text-splitters, huggingface), `lint_package` also overrides
`UV_RUN_TYPE` to `--group lint --group typing`, skipping the ~3.5GB
`test_integration` download entirely. `lint_tests` keeps `--all-groups`
since test code legitimately imports those deps.
Additionally, `lint_imports.sh` was inconsistently wired — most packages
had the script but weren't calling it.
## Changes
**Makefile optimization**
- Introduce `UV_RUN_LINT` and `UV_RUN_TYPE` Make variables, both
defaulting to `uv run --all-groups`. For `lint_package` and
`lint_tests`, `UV_RUN_LINT` is overridden to `uv run --group lint` so
ruff runs instantly without syncing heavy deps
- For `text-splitters` and `huggingface`, override `UV_RUN_TYPE` on
`lint_package` to `uv run --group lint --group typing` — mypy runs
without downloading torch, CUDA, spacy, etc.
**mypy config for lean groups**
- Add `transformers` and `transformers.*` to `ignore_missing_imports` in
`text-splitters` pyproject.toml (conditional `try/except` import, same
treatment as existing `konlpy`/`nltk` entries)
- Add `torch`, `torch.*`, `langchain_community`, `langchain_community.*`
to `ignore_missing_imports` in `huggingface` pyproject.toml
- Add dual `# type: ignore[unreachable, unused-ignore]` in
`text-splitters/base.py` to handle the `PreTrainedTokenizerBase`
isinstance check that behaves differently depending on whether
transformers is installed
**lint_imports.sh consistency**
- Add `./scripts/lint_imports.sh` to the lint recipe in every package
that wasn't calling it (standard-tests, model-profiles, all 15
partners), and create the script for the two packages missing it
entirely (`model-profiles`, `openrouter`)
- Update all `lint_imports.sh` scripts to allow `from langchain.agents`
and `from langchain.tools` imports (legitimate v1 middleware
dependencies used by `langchain-anthropic` and `langchain-openai`)
it looks scary but i promise it is not
improving documentation consistency across core. primarily update
docstrings and comments for better formatting, readability, and
accuracy, as well as add minor clarifications and formatting
improvements to user-facing documentation.
As mentioned in #18322, the current PydanticOutputParser won't work for
anyone trying to parse to pydantic v2 models. This PR adds a separate
`PydanticV2OutputParser`, as well as a `langchain_core.pydantic_v2`
namespace that will fail on import to any projects using pydantic<2.
Happy to update the docs for output parsers if this is something we're
interesting in adding.
On a separate note, I also updated `check_pydantic.sh` to detect
pydantic imports with leading whitespace and excluded the internal
namespaces. That change can be separated into its own PR if needed.
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Co-authored-by: Jan Nissen <jan23@gmail.com>