Help/variable/CMAKE_TEST_BUILD_DEPENDS.rst

CMAKE_TEST_BUILD_DEPENDS
------------------------

.. versionadded:: 4.4

.. versionchanged:: 4.5

  :generator:`FASTBuild` and the :ref:`Makefile Generators` gained support
  for ``test_prep/<name>`` targets.

Enable ``test_prep/<name>`` build targets for tests added by
:command:`add_test` when using the :ref:`Ninja Generators`,
:generator:`FASTBuild`, or :ref:`Makefile Generators`.

When this variable is set to a true value, CMake generates a
``test_prep/<name>`` target for each eligible test and a ``test_prep/all``
target for all such tests. Building these targets ensures the test executable,
targets referenced by test command generator expressions, and explicit
``BUILD_DEPENDS`` entries are up-to-date before the test runs.

Tests whose names are not valid target names are excluded from this behavior.
If multiple tests in different directories share the same name, their
dependencies are merged into a single ``test_prep/<name>`` target.

With the :ref:`Makefile Generators`, a ``BUILD_DEPENDS`` file is built by
building the target whose build produces it.  A generated file that is not the
unique output of a single target is reported with a warning, and a test whose
name contains a ``:`` character is excluded because it cannot be expressed as
a Makefile target.