DunePythonVirtualenv

This module manages the creation of virtual python environment during configuration. Execution of this module must be explicitly enabled by setting the variable DUNE_PYTHON_VIRTUALENV_SETUP. Note that some downstream modules will require you to set this variable. The purpose of this virtual environment is to be able to run python code from cmake in situations such as python-based code generation, running postprocessing in python during testing etc.

Although designed for internal use, this virtualenv can also be manually inspected. A symlink to the activation script is placed in the top level build directory of all Dune modules in the stack. To directly execute a command in the virtualenv, you can use the script run-in-dune-env <command>, which is also placed into every build directory.

All packages installed with dune_python_install_package are automatically installed into the virtualenv.

After execution of this module, the following are available for use in downstream modules:

• DUNE_PYTHON_VIRTUALENV_PATH The path of the virtual environment

• DUNE_PYTHON_VIRTUALENV_EXECUTABLE The python interpreter in the virtual environment

By default, the created virtualenv resides in the first non-installed Dune module of the module stack (if no installation is performed: dune-common). Be aware that mixing installed and non-installed modules may result in a situation, where multiple such environments are created, although only one should. You can change this behavior by either specifying a fixed path for the virtualenv using DUNE_PYTHON_VIRTUALENV_PATH or by enabling DUNE_PYTHON_EXTERNAL_VIRTUALENV_FOR_ABSOLUTE_BUILDDIR if you are using an absolute build directory with dunecontrol. Note that this flag is enabled by default starting from Dune 2.7.