# print list of tests via TEST\_LIST variable
**URL:** https://discourse.cmake.org/t/print-list-of-tests-via-test-list-variable/5277
**Category:** Usage
**Tags:** os:linux, tool:ctest
**Created:** [March 24, 2022, 12:17am UTC](https://discourse.cmake.org/t/print-list-of-tests-via-test-list-variable/5277 "2022-03-24T00:17:36Z")
**Posts on this page:** 8
**Page:** 1
### Author:  [@yisseamake](https://discourse.cmake.org/u/yisseamake)
#### Post date: [March 24, 2022, 12:17am UTC](https://discourse.cmake.org/t/print-list-of-tests-via-test-list-variable/5277/1 "2022-03-24T00:17:36Z")
Could you please advise how view/print list of tests discovered by gtest\_discover\_tests. As per 3.17.5 user guide the option `TEST_LIST var` Make the list of tests available in the variable `var`… Note that this variable is only available in CTest."
```cmake
gtest_discover_tests(lib_gtest
WORKING_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR}
TEST_LIST lib_test_list
PROPERTIES ENVIRONMENT
MYCONFIG_PATH=${CMAKE_CURRENT_SOURCE_DIR}
)
```
What does it mean “available in CTest”? is there example to print it?
The way ctest is executed is as the following template:
```cmake
add_custom_command(TARGET lib_gtest
POST_BUILD
COMMAND ${CMAKE_COMMAND} -E env ... ctest -j4 --output-on-failure --gtest_output=xml:lib_gtest_report.xml
....
)
```
So could you please advise on:
1. How to print TEST\_LIST variable lib\_test\_list ?
2. What does this mean " `gtest_discover_tests` sets up a post-build command on the test executable that generates the list of tests by parsing the output from running the test with the `--gtest_list_tests` argument" ? Is --gtest\_list\_tests argument to ctest needed?
3. What does this mean " Additionally, setting properties on tests is somewhat less convenient, since the tests are not available at CMake time. Additional test properties may be assigned to the set of tests as a whole using the `PROPERTIES` option." - does it mean set\_tests\_properties() wont work on discovered tests? I tried it and got error that test is not found.
4. What is proper use of PROPERTIES ENVIRONMENT ? Is it really parameter value like MYCONFIG\_PATH ${NEWPATH} or parameter=value “MYCONFIG\_PATH=${NEWPATH}”? , see [googletest - With CMake, how can I set environment properties on the gtest\_discover\_tests --gtest\_list\_tests call? - Stack Overflow](https://stackoverflow.com/questions/57541741/with-cmake-how-can-i-set-environment-properties-on-the-gtest-discover-tests-g)
. Note, OS Linux, cmake 3.17
---
### Author:  [@craig.scott](https://discourse.cmake.org/u/craig.scott)
#### Post date: [March 24, 2022, 7:44am UTC](https://discourse.cmake.org/t/print-list-of-tests-via-test-list-variable/5277/2 "2022-03-24T07:44:58Z")
> [@yisseamake](#):
>
> How to print TEST\_LIST variable lib\_test\_list ?
You need to create a custom ctest file, which will be processed when `ctest` runs. It uses the same syntax language as CMake, but it is run at test time, not at configure time. Put something like this in your `CMakeLists.txt` file to tell CMake to process it at test time:
```cmake
set_property(DIRECTORY APPEND PROPERTY
TEST_INCLUDE_FILES ${CMAKE_CURRENT_LIST_DIR}/customTestManip.cmake
)
```
Then in `customTestManip.cmake`, you’d have code like this:
```cmake
message(STATUS "List of tests: ${lib_test_list}")
```
The above is untested, but should be in the ballpark.
> [@yisseamake](#):
>
> What does this mean " `gtest_discover_tests` sets up a post-build command on the test executable that generates the list of tests by parsing the output from running the test with the `--gtest_list_tests` argument" ? Is --gtest\_list\_tests argument to ctest needed?
No you don’t need to add `--gtest_list_tests`. That sentence is just telling you what the command does internally.
---
### Author:  [@yisseamake](https://discourse.cmake.org/u/yisseamake)
#### Post date: [March 24, 2022, 3:22pm UTC](https://discourse.cmake.org/t/print-list-of-tests-via-test-list-variable/5277/3 "2022-03-24T15:22:21Z")
Thank you for quick response.
> [@craig.scott](#):
>
> ` ` You need to create a custom ctest file, which will be processed when `ctest` runs
Does this mean that add\_custom\_command(TARGET lib\_gtest
POST\_BUILD …
better be removed as well and all ctest processing be concentrated in customTestManip.cmake ?
4. Could you please respond to item 4. above?
I tried the above solution and it did not produce any list. However I do see a file created by ctest:
`${CMAKE_BINARY_DIR}/Testing/Temporary/CTestCostData.txt` This file stores data for each test in a row. So effectively it provides list of tests. However this list has been created without suggested change to set TEST\_INCLUDE\_FILES.
I still want to get your advise on printing this list but I dont like using non-target specific command like set\_property so can this be done with set\_target\_properties or set\_tests\_properties? The latter seems does not work with gtest\_discover\_tests as I am getting no tests found error message.
Therefore the bigger question is how to set properties (e.g. environment variables to pass to test .cpp etc. ) if test are discovered with gtest\_discover\_tests?
---
### Author:  [@craig.scott](https://discourse.cmake.org/u/craig.scott)
#### Post date: [March 25, 2022, 4:28am UTC](https://discourse.cmake.org/t/print-list-of-tests-via-test-list-variable/5277/4 "2022-03-25T04:28:11Z")
> [@yisseamake](#):
>
> Does this mean that add\_custom\_command(TARGET lib\_gtest
> POST\_BUILD …
> better be removed as well
Yes
> [@yisseamake](#):
>
> What is proper use of PROPERTIES ENVIRONMENT ? Is it really parameter value like MYCONFIG\_PATH ${NEWPATH} or parameter=value “MYCONFIG\_PATH=${NEWPATH}”? , see [googletest - With CMake, how can I set environment properties on the gtest\_discover\_tests --gtest\_list\_tests call? - Stack Overflow](https://stackoverflow.com/questions/57541741/with-cmake-how-can-i-set-environment-properties-on-the-gtest-discover-tests-g)
Opening a big can of worms! This is also mostly why I didn’t have time to respond to this item in my earlier reply. 😉 First point, there’s no easy way to pass through a property that contains a value that is a list. There are multiple levels of CMake parsing involved, which results in making it unreliable to try to preserve the list. This is what the stackoverflow issue you linked to is mostly about, but I wouldn’t recommend the approach given in that answer. I’ll refer you to the following recently submitted issue for a deeper discussion, very relevant to your problem:
[https://gitlab.kitware.com/cmake/cmake/-/issues/23329](https://gitlab.kitware.com/cmake/cmake/-/issues/23329)
As recommended in that issue, take a look at the [`ENVIRONMENT_MODIFICATION`](https://cmake.org/cmake/help/latest/prop_test/ENVIRONMENT_MODIFICATION.html) test property, which became available in CMake 3.22.
But ultimately, I think you’re still in trouble. Here’s another issue which I think captures the crux of the problem you’re facing:
[https://gitlab.kitware.com/cmake/cmake/-/issues/21453](https://gitlab.kitware.com/cmake/cmake/-/issues/21453)
In short, test discovery on Windows is a real bummer when the target needs to find DLLs at discovery time.
---
### Author:  [@yisseamake](https://discourse.cmake.org/u/yisseamake)
#### Post date: [March 28, 2022, 2:16pm UTC](https://discourse.cmake.org/t/print-list-of-tests-via-test-list-variable/5277/5 "2022-03-28T14:16:19Z")
Thank you Sir. Luckily these 2 links refers to complications which I might not affected by. I need to pass single (not a list) tuple variable-value for single path MYCONFIG\_PATH string from cmake PROPERTIES ENVIRONMENT to test cpp and I do not need to support Windows at the moment, just Linux. So with this limitation what would be the correct solution?
Still what is the proper way to set properties (e.g. environment variables to pass to test .cpp etc. ) if test are discovered with gtest\_discover\_tests?
---
### Author:  [@craig.scott](https://discourse.cmake.org/u/craig.scott)
#### Post date: [March 30, 2022, 4:47am UTC](https://discourse.cmake.org/t/print-list-of-tests-via-test-list-variable/5277/6 "2022-03-30T04:47:31Z")
If all you need to is to set `MYCONFIG_PATH` to a value that will never contain a semicolon, and that’s the only environment variable you need to set, then specifying it with the `PROPERTIES` keyword in the call to `gtest_discover_tests()` like in your original post would be the simplest method.
---
### Author:  [@yisseamake](https://discourse.cmake.org/u/yisseamake)
#### Post date: [March 30, 2022, 2:15pm UTC](https://discourse.cmake.org/t/print-list-of-tests-via-test-list-variable/5277/7 "2022-03-30T14:15:11Z")
That’s what I did in the “PROPERTIES ENVIRONMENT” line in my sample code above but the question I have is about syntax as I tried to use it per documentation “[PROPERTIES name1 value1…” first and itr did not work and example I referred uses “PROPERTIES name1 value1” like in my sample above MYCONFIG\_PATH=${CMAKE\_CURRENT\_SOURCE\_DIR}
---
### Author:  [@craig.scott](https://discourse.cmake.org/u/craig.scott)
#### Post date: [April 2, 2022, 12:57am UTC](https://discourse.cmake.org/t/print-list-of-tests-via-test-list-variable/5277/8 "2022-04-02T00:57:38Z")
> [@yisseamake](#):
>
> ```auto
> gtest_discover_tests(lib_gtest
> WORKING_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR}
> TEST_LIST lib_test_list
> PROPERTIES ENVIRONMENT
> MYCONFIG_PATH=${CMAKE_CURRENT_SOURCE_DIR}
> )
>
> ```
The above should work. It should set the `ENVIRONMENT` property of each discovered test such that the tests see `MYCONFIG_PATH` set to `${CMAKE_CURRENT_SOURCE_DIR}`. If that isn’t happening for you, please open an issue in the [CMake issue tracker](https://gitlab.kitware.com/cmake/cmake/-/issues/new) with a minimal project that reproduces the problem.