======================= Development Environment

.. warning::

These instructions have some inaccuracies on Windows.

Get the code and Mamba

Clone the repo

Fork and clone the repository in your preferred manner. Refer to GitHub documentation for how to do so.

Install micromamba

Setting the development environment requires conda, mamba, or micromamba. Since some commands are automated with micromamba, and to avoid any runtime linking issue, it is best to work with micromamba.

Refer to the :ref:installation<umamba-install> page for how to install micromamba or mamba.

Running commands manually

.. note::

The CI files in .github/workflow provide an alternative way of developing Mamba.

Install development dependencies

.. code:: bash

micromamba create -n mamba -c conda-forge -f dev/environment-dev.yml
micromamba activate mamba

Compile libmamba and other artifacts

libmamba is built using CMake. Typically during development, we build everything dynamically using dependencies from Conda-Forge.

The first step is to configure the build options. A recommended set is already provided as CMake Preset, but feel free to use any variations.

.. note:: If you do choose to use the provided CMake Preset, you may need to install ccache as an extra requirement as specified in dev/environment-dev-extra.yml.

.. note:: All cmake commands listed below use bash multi-line syntax. On Windows, replace \ trailing character with ^.

.. code:: bash

cmake -B build/ -G Ninja --preset mamba-unix-shared-debug-dev

Compilation can then be launched with:

.. code:: bash

cmake --build build/ --parallel

libmamba tests

The tests for libmamba are written in C++.

.. code:: bash

./build/libmamba/tests/test_libmamba

mamba/micromamba integration tests

Many mamba integration tests are written through a pytest Python wrapper. The environment variable TEST_MAMBA_EXE controls which executable is being tested.

.. code:: bash

export TEST_MAMBA_EXE="${PWD}/build/micromamba/mamba" python -m pytest micromamba/tests

libmambapy tests

To run the libmambapy tests, the Python package needs to be properly installed first.

.. warning::

This needs to be done every time libmamba changes.

.. code:: bash

cmake --install build/ --prefix "${CONDA_PREFIX}"

Then the Python bindings can be installed

.. code:: bash

python -m pip install --no-deps --no-build-isolation libmambapy/

Finally the tests can be run:

.. code:: bash

python -m pytest libmambapy/tests

Code Formatting

Code formatting is done using Pre-Commit hooks. Whichever way you decided to install development dependencies, we recommend installing Pre-Commit hooks with

.. code:: bash

pre-commit install

Alternatively, the checks can be run manually

.. code:: bash

pre-commit run --all-files