[Testing] Externalize (find_package() or fetch) googletest/gtest

[fredroy]

Originally, the goal was not really to go for

• Use of embedded external dependencies #4221

But more to upgrade the gtest version, as the one in SOFA is really old (1.7.0 , Sep 19, 2013 ❗ ) and was throwing warnings for newer cmake.
So instead of simply update the source in extlibs, I took the liberty to go into the find/fetch mechanism.

A bit difficult as the CMakefile in the embedded version was heavily customized, so I am not 100% sure the install/package process is working well. But it should 😅

Last note: it is adding a target gtest_main which is always activated in the gtest cmake file. It is not used by SOFA as we have our own main for gtest.

[ci-depends-on https://github.com/sofa-framework/PluginExample/pull/5]

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[fredroy]

[ci-build][with-all-tests]

[fredroy]

[ci-build][with-all-tests][force-full-build]

[sofabot]

[ci-depends-on] detected during build #4.

To unlock the merge button, you must

• Merge or close Instanciate test suite PluginExample#5
  For this build, PluginExample/ExternalProjectConfig.cmake.in will be edited by builders with
  GIT_REPOSITORY https://github.com/sofa-framework/PluginExample
  GIT_TAG 56823196e7f8d1793d601707be1bd3efac4a056b

[sofabot]

[ci-depends-on] detected during build #5.

All dependencies are merged/closed and all ExternalProject pointers are up-to-date. Congrats! 👍

[olivier-roussel]

With the following adjustments, this compiles both using fetched gtest or using external gtest package from conda (tested on linux-x64 with gtest 1.14.0 from conda-forge).

[fredroy]

@olivier-roussel thanks for the conda test and the feedbacks 👍
You should have made suggestions and/or make a PR on my branch, as I cannot credit you your patches 😵

[sofabot]

[ci-depends-on] detected during build #6.

All dependencies are merged/closed and all ExternalProject pointers are up-to-date. Congrats! 👍

[sofabot]

[ci-depends-on] detected during build #7.

All dependencies are merged/closed and all ExternalProject pointers are up-to-date. Congrats! 👍

[sofabot]

[ci-depends-on] detected during build #8.

All dependencies are merged/closed and all ExternalProject pointers are up-to-date. Congrats! 👍

[fredroy]

[ci-build][with-all-tests][force-full-build]

[sofabot]

[ci-depends-on] detected during build #9.

All dependencies are merged/closed and all ExternalProject pointers are up-to-date. Congrats! 👍

[sofabot]

[ci-depends-on] detected during build #10.

All dependencies are merged/closed and all ExternalProject pointers are up-to-date. Congrats! 👍

[fredroy]

@olivier-roussel
The findGTest https://cmake.org/cmake/help/v3.19/module/FindGTest.html of cmake only works for CMake >= 3.20 😭
(tested with cmake 3.16 and 3.19 ❌ whereas cmake 3.20 and 3.28 ✅)

[olivier-roussel]

@olivier-roussel thanks for the conda test and the feedbacks 👍 You should have made suggestions and/or make a PR on my branch, as I cannot credit you your patches 😵

Indeed, sorry about that

[olivier-roussel]

@olivier-roussel The findGTest https://cmake.org/cmake/help/v3.19/module/FindGTest.html of cmake only works for CMake >= 3.20 😭 (tested with cmake 3.16 and 3.19 ❌ whereas cmake 3.20 and 3.28 ✅)

Indeed again 😢
Another option but maybe a bit conda-specific would be to switch to config mode find_package(GTest CONFIG QUIET), as the conda package comes with the GTest cmake config files. Tested with conda + cmake 3.19.

[olivier-roussel]

Ok so maybe I misunderstood your last comment, but the GTest find module you added in your last commit works fine on my side with cmake >= 3.12 (which is our min required version). So I guess you meant that the embedded GTest find module in recent cmake version (>=3.20) was required to have the correct targets defined, which is not the case in earlier <3.20 version of cmake (tested in 3.12), but this recent GTest find module was not building if used with cmake <3.20. In the end, your last commit seems to fix everything, so looks like a more generic option that relying on cmake config files as suggested in my last comment.

[fredroy]

Ok so maybe I misunderstood your last comment, but the GTest find module you added in your last commit works fine on my side with cmake >= 3.12 (which is our min required version). So I guess you meant that the embedded GTest find module in recent cmake version (>=3.20) was required to have the correct targets defined, which is not the case in earlier <3.20 version of cmake (tested in 3.12), but this recent GTest find module was not building if used with cmake <3.20. In the end, your last commit seems to fix everything, so looks like a more generic option that relying on cmake config files as suggested in my last comment.

I just added the cmake module from v3.20 for GTest directly in our cmake folder modules; not very clean but it does the job apparently 👍

[sofabot]

[ci-depends-on] detected during build #14.

All dependencies are merged/closed and all ExternalProject pointers are up-to-date. Congrats! 👍

[sofabot]

[ci-depends-on] detected during build #15.

All dependencies are merged/closed and all ExternalProject pointers are up-to-date. Congrats! 👍