vscode-cython

Main Repository

Cyright LSP Repository

Cython Language Extension for VS Code

Features

• Syntax highlighting
• Static syntax checking for C and CPP syntax
• Go to definitions
• Import resolver for .pxd files
• Typestub generation (.pyi) for .pyx files (Experimental)

About

This extension provides syntax highlighting and a Static Syntax checker for the Cython language. Cython is a superset of Python with it's own C-styled syntax mixed with Python syntax.

The static checker is based on Pyright and will only support Cython/Python syntax version 3.0 and above.

This extension uses the configured Python interpreter/venv path from the VS Code Python extension.

Commands

cython.compileCurrentFile

Runs cythonize to build current/selected .pyx file inplace. Useful for smaller files that can be built without setuptools or other build system.

Availability

• Command Palette
• Explorer context menu

cython.createTypeStub

Experimental.

Create a typestub (.pyi) file for current/selected .pyx file. These files can be used within Python for static typing.

Availability

• Command Palette
• Explorer context menu

Limitations

• Only cimports that are .pxd files will be recognized
• The 'Pure Python' syntax is not supported
• Directives will not be considered. This is because directives can be set in multiple places such as in a setup.py file and cannot be analyzed statically
• Pyright options are not supported. i.e. pyrightconfig.json

Possible features

These features would be nice to have but are not implemented.

• Strict type analysis
• C headers analysis / inline C code analysis
• Python interaction highlighting

FAQ

• If no problems are reported will my code compile?

  No. There are no guarantees that code will be compiled correctly

Issues

Please report any issues in this repo.

Installing

Install with VS Code

Install normally through the extensions tab.

Install from source

• Clone repo. For installation clone in the <user home>/.vscode/extensions folder.

• Ensure submodules are fetched with:

  git submodule update --init --recursive
  

• Install npm

Building source

• To build extension run:

  npm install --include=dev
  npm run build:extension
  

Building vsix package

Alternatively, a vsix package can be built:

npm install vsce
npx vsce package
code --install-extension vscode-cython-<version>.vsix

Development

Setup

To setup development environment:

• Follow the instructions for Installing from source (repo can be cloned anywhere on filesystem) (build step can be skipped).

• Install development npm packages:

  npm install --include=dev
  

• To rebuild lang-server and syntax file, Run:

  npm run build:extension:dev
  

Debugging

Run the Watch extension task. This can be done in vscode by clicking view->Command Palette and then selecting Tasks: Run Build Task and then selecting Watch extension.

This will build the language server and the source code will be watched for changes

You can then run the launch task: Extension which will launch the extension in debug mode.

After the extension has been launched run the launch task Attach server, which will attach the debugger to the extension.

Syntax highlighting changes

Any changes should be made to ./grammars/cython.syntax.yaml

The syntax file will need to be re-generated for VS Code to see changes.

To re-generate syntax file run:

npm run build:syntax

Language Server (Cyright) Development

Pull requests should be created under the Cyright Repository.

There is a 'Watch Extension' task to aid in development. The language server can be debugged by launching the 'Extension' launch target and then launching the 'Attach Server' target.