lsp-types 0.14.0

Zero-dependency Python library for Language Server Protocol types

LSP Types

Publish the excellent work of Sublime LSP as a PyPI package.

LSP Types is a Python package that aims to provide a fully typed interface to Language Server Protocol (LSP) interactions. It can be used to simply utilize the types, or to interact with an LSP server over stdio.

The library has minimal dependencies (tomli-w for TOML config serialization).

Installation

pip install lsp-types

Usage

Using the LSP types:

import lsp_types

# Use the types

Using an LSP process through stdio:

[!TIP] Recommend using basedpyright for extended features.

from lsp_types.process import LSPProcess, ProcessLaunchInfo

process_info = ProcessLaunchInfo(cmd=[
    "pyright-langserver", "--stdio"
])

async with LSPProcess(process_info) as process:
    # Initialize the process
    ...

    # Grab a typed listener
    diagnostics_listener = process.notify.on_publish_diagnostics(timeout=1.0)

    # Send a notification (`await` is optional. It ensures messages have been drained)
    await process.notify.did_open_text_document(...)

    # Wait for diagnostics to come in
    diagnostics = await diagnostics_listener

LSPs

The following LSPs are available out of the box:

• Pyright
• Pyrefly
• ty - Astral's fast Python type checker

Pyright Example

from lsp_types import Session
from lsp_types.pyright.backend import PyrightBackend

async def test_pyright_session():
    code = """\
def greet(name: str) -> str:
    return 123
"""

    session = await Session.create(PyrightBackend(), initial_code=code)
    diagnostics = await session.get_diagnostics()

    assert diagnostics != []

    code = """\
def greet(name: str) -> str:
    return f"Hello, {name}"
"""

    await session.update_code(code)
    diagnostics = await session.get_diagnostics()
    assert diagnostics == []

    await session.shutdown()

Development

• Requires Python 3.12+.
• Requires uv for dev dependencies.

Generate latest types in one go:

make generate-latest-types

Download the latest json schema:

make download-schemas

Generate the types:

make generate-types

Copy the lsp_types/types.py file to your project.

NOTE: Do not import types that begin with __. These types are internal types and are not meant to be used.

TODOs

• Support server request handlers.