a2e53fda73
Switches type checking for `langchain-text-splitters` from `mypy` to [`ty`](https://docs.astral.sh/ty/), which is much faster. The `ollama` package already [switched to `ty`](https://github.com/langchain-ai/langchain/pull/36571). ## What changed The core of this PR is the config swap (`[tool.mypy]` → `[tool.ty.rules]`/`[tool.ty.analysis]`, `Makefile`, and the `typing` dependency group). Because `ty` runs with `all = "error"`, a few modules also needed source-level adjustments to satisfy the stricter analysis. These are **behavior-preserving refactors** except for one intentional fix, called out below so reviewers know where to look. ### Behavioral change (intentional fix) - `SentenceTransformersTokenTextSplitter` now raises a clear `ValueError` when the underlying model reports no maximum sequence length **and** no `tokens_per_chunk` was provided. Previously this combination reached a `None > None` comparison and surfaced as an opaque `TypeError`. As a consequence, the public `maximum_tokens_per_chunk` attribute is now honestly typed as `int | None` — it can remain `None` when the caller supplies `tokens_per_chunk` explicitly for a model without a limit. ### Behavior-preserving refactors (no user-visible change) - `TokenTextSplitter.from_tiktoken_encoder` is now an explicit override rather than the base method dispatching on `issubclass(cls, TokenTextSplitter)`. The shared length-function logic moved into a private helper. Public signatures and return types are unchanged. - `NLTKTextSplitter` builds its tokenizer once at construction, so `_tokenizer` is now always a `Callable[[str], list[str]]`. The private attributes `_language` and `_use_span_tokenize` are no longer stored — flagging in case any downstream code read those (they are underscore-private). Tokenization output is unchanged. - `HTMLSemanticPreservingSplitter` text extraction was rewritten from a `cast`-based check to `isinstance(element, Tag)` narrowing; output is equivalent for tags, text nodes, and comments. --------- Co-authored-by: Mason Daugherty <github@mdrxy.com>
🦜✂️ LangChain Text Splitters
Looking for the JS/TS version? Check out LangChain.js.
Quick Install
uv add langchain-text-splitters
🤔 What is this?
LangChain Text Splitters contains utilities for splitting into chunks a wide variety of text documents.
📖 Documentation
For full documentation, see the API reference.
📕 Releases & Versioning
See our Releases and Versioning policies.
We encourage pinning your version to a specific version in order to avoid breaking your CI when we publish new tests. We recommend upgrading to the latest version periodically to make sure you have the latest tests.
Not pinning your version will ensure you always have the latest tests, but it may also break your CI if we introduce tests that your integration doesn't pass.
💁 Contributing
As an open-source project in a rapidly developing field, we are extremely open to contributions, whether it be in the form of a new feature, improved infrastructure, or better documentation.
For detailed information on how to contribute, see the Contributing Guide.
Resources
- LangChain Academy — comprehensive, free courses on LangChain libraries and products, made by the LangChain team
- Code of Conduct — community guidelines and standards