1# How to develop Lark - Guide 2 3There are many ways you can help the project: 4 5* Help solve issues 6* Improve the documentation 7* Write new grammars for Lark's library 8* Write a blog post introducing Lark to your audience 9* Port Lark to another language 10* Help me with code development 11 12If you're interested in taking one of these on, let me know and I will provide more details and assist you in the process. 13 14 15## Unit Tests 16 17Lark comes with an extensive set of tests. Many of the tests will run several times, once for each parser configuration. 18 19To run the tests, just go to the lark project root, and run the command: 20```bash 21python -m tests 22``` 23 24or 25 26```bash 27pypy -m tests 28``` 29 30For a list of supported interpreters, you can consult the `tox.ini` file. 31 32You can also run a single unittest using its class and method name, for example: 33```bash 34## test_package test_class_name.test_function_name 35python -m tests TestLalrStandard.test_lexer_error_recovering 36``` 37 38### tox 39 40To run all Unit Tests with tox, 41install tox and Python 2.7 up to the latest python interpreter supported (consult the file tox.ini). 42Then, 43run the command `tox` on the root of this project (where the main setup.py file is on). 44 45And, for example, 46if you would like to only run the Unit Tests for Python version 2.7, 47you can run the command `tox -e py27` 48 49### pytest 50 51You can also run the tests using pytest: 52 53```bash 54pytest tests 55``` 56 57### Using setup.py 58 59Another way to run the tests is using setup.py: 60 61```bash 62python setup.py test 63``` 64