build_helpers.sh

function _helper_conda_available() {
    $(command -v conda &> /dev/null) && \
    $(command -v conda activate &> /dev/null)
}

function _helper_fail {
    printf '%s\n' "FAIL: $1" >&2
    : "${__fail_fast:?$1}";
}

function _helper_assert_in_env() {
    _helper_conda_available || _helper_fail "Conda is not available."
    if [ ! "${CONDA_PREFIX}" ]; then _helper_fail "Not in a conda env."; fi
    if [[ "${CONDA_DEFAULT_ENV}" == "base" ]]; then _helper_fail "Do not mess with the base env."; fi
}

function make_clean_env() {
    ENV_NAME="$1"
    if [ ! "${ENV_NAME}" ]; then
        echo "Usage: make_clean_env ENV_NAME [PY_VERSION]"
        echo "Create a new conda environment and configure for PyTorch."
        echo "Example: make_clean_env my_env 3.8"
    fi

    # Make sure we are in a clean state. (10 deep should be plenty...)
    _helper_conda_available || _helper_fail "Conda is not available"
    for i in {1..10}; do
        if [ ! -z $CONDA_PREFIX ]; then
            conda deactivate || true
        fi
    done

    PY_VERSION="${2:-3.10}"
    conda env remove --name "${ENV_NAME}" 2> /dev/null || _helper_fail "Cleanup old env: ${ENV_NAME}"
    conda create --no-default-packages -y -n "${ENV_NAME}" python="${PY_VERSION}" || _helper_fail "Make env: ${ENV_NAME}"

    # Drop back to base env.
    conda deactivate && conda activate
    printf "\nENV:    ${ENV_NAME}\nPython: ${PY_VERSION}\n\n"
}