We need to inform CTest that tests need to be terminated if they go into overtime, as follows:

1. We define the project name, enable testing, and define the test:

# set minimum cmake version
cmake_minimum_required(VERSION 3.5 FATAL_ERROR)

# project name
project(recipe-07 LANGUAGES NONE)

# detect python
find_package(PythonInterp REQUIRED)

# define tests
enable_testing()

# we expect this test to run for 2 seconds
add_test(example ${PYTHON_EXECUTABLE} ${CMAKE_CURRENT_SOURCE_DIR}/test.py)

2. In addition, we specify a TIMEOUT for the test, and set it to 10 seconds:

set_tests_properties(example PROPERTIES TIMEOUT 10)

3. We know how to configure and build, and we expect the test to pass:

$ ctest

Test project /home/user/cmake-recipes/chapter-04/recipe-07/example/build
    Start 1: example
1/1 Test #1: example .......................... Passed 2.01 sec

100% tests passed, 0 tests failed out of 1

Total Test time (real) = 2.01 sec

4. Now, to verify that the TIMEOUT works, we increase the sleep command in test.py to 11 seconds, and rerun the test:

$ ctest

Test project /home/user/cmake-recipes/chapter-04/recipe-07/example/build
    Start 1: example
1/1 Test #1: example ..........................***Timeout 10.01 sec

0% tests passed, 1 tests failed out of 1

Total Test time (real) = 10.01 sec

The following tests FAILED:
          1 - example (Timeout)
Errors while running CTest