How to develop Lark - Guide¶
There are many ways you can help the project:
Help solve issues
Improve the documentation
Write new grammars for Lark’s library
Write a blog post introducing Lark to your audience
Port Lark to another language
Help with code development
If you’re interested in taking one of these on, contact us on Gitter or Github Discussion, and we will provide more details and assist you in the process.
Lark does not follow a predefined code style. We accept any code style that makes sense, as long as it’s Pythonic and easy to read.
Lark comes with an extensive set of tests. Many of the tests will run several times, once for each parser configuration.
To run the tests, just go to the lark project root, and run the command:
python -m tests
pypy -m tests
For a list of supported interpreters, you can consult the
You can also run a single unittest using its class and method name, for example:
## test_package test_class_name.test_function_name python -m tests TestLalrBasic.test_keep_all_tokens
To run all Unit Tests with tox,
install tox and Python 2.7 up to the latest python interpreter supported (consult the file tox.ini).
run the command
tox on the root of this project (where the main setup.py file is on).
And, for example,
if you would like to only run the Unit Tests for Python version 2.7,
you can run the command
tox -e py27
You can also run the tests using pytest:
Another way to run the tests is using setup.py:
python setup.py test