Development¶

Prerequisites:

Install task;
Install docker, with buildkit;

Spin up docker compose based dev env - task dev:up
Run jlpm watch inside dev container - task dev:jlpm-watch
In another terminal, run jupyter lab inside dev container - task dev:jupyter-lab

This watches the source directory and run JupyterLab at the same time in different terminals to watch for changes in the extension’s source and automatically rebuild the extension inside the dev docker container.

With the watch command running, every saved change will immediately be built locally and available in your running JupyterLab. Refresh JupyterLab to load the change in your browser (you may need to wait several seconds for the extension to be rebuilt).

Development install¶

Note: You will need NodeJS to build the extension package.

The jlpm command is JupyterLab’s pinned version of yarn that is installed with JupyterLab. You may use yarn or npm in lieu of jlpm below.

# Clone the repo to your local environment
# Change directory to the jupyterlab_code_formatter directory

# Set up a virtual environment and install package in development mode
python -m venv .venv
source .venv/bin/activate
pip install --editable ".[dev,test]"

# Link your development version of the extension with JupyterLab
jupyter labextension develop . --overwrite
# Server extension must be manually installed in develop mode
jupyter server extension enable jupyterlab_code_formatter

# Rebuild extension Typescript source after making changes
# IMPORTANT: Unlike the steps above which are performed only once, do this step
# every time you make a change.
jlpm build

You can watch the source directory and run JupyterLab at the same time in different terminals to watch for changes in the extension’s source and automatically rebuild the extension.

# Watch the source directory in one terminal, automatically rebuilding when needed
jlpm watch
# Run JupyterLab in another terminal
jupyter lab

By default, the jlpm build command generates the source maps for this extension to make it easier to debug using the browser dev tools. To also generate source maps for the JupyterLab core extensions, you can run the following command:

jupyter lab build --minimize=False

Development uninstall¶

# Server extension must be manually disabled in develop mode
jupyter server extension disable jupyterlab_code_formatter
pip uninstall jupyterlab_code_formatter

In development mode, you will also need to remove the symlink created by jupyter labextension develop command. To find its location, you can run jupyter labextension list to figure out where the labextensions folder is located. Then you can remove the symlink named jupyterlab-code-formatter within that folder.

Testing the extension¶

Server tests¶

This extension is using Pytest for Python code testing.

Install test dependencies (needed only once):

pip install -e ".[test]"
# Each time you install the Python package, you need to restore the front-end extension link
jupyter labextension develop . --overwrite

To execute them, run:

pytest -vv -r ap --cov jupyterlab_code_formatter

Frontend tests¶

This extension is using Jest for JavaScript code testing.

To execute them, execute:

jlpm
jlpm test

Integration tests¶

This extension uses Playwright for the integration tests (aka user level tests). More precisely, the JupyterLab helper Galata is used to handle testing the extension in JupyterLab.

More information are provided within ./ui-tests/README.md.

Packaging the extension¶

See ./RELEASE.md