ONNX will build googletest from a Git checkout.  Patch CMake to use our
googletest package and enable tests by default.

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 0aa9fda2..a573170c 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -22,7 +22,7 @@ option(BUILD_ONNX_PYTHON "Build Python binaries" OFF)
 option(ONNX_GEN_PB_TYPE_STUBS "Generate protobuf python type stubs" ON)
 option(ONNX_WERROR "Build with Werror" OFF)
 option(ONNX_COVERAGE "Build with coverage instrumentation" OFF)
-option(ONNX_BUILD_TESTS "Build ONNX C++ APIs Tests" OFF)
+option(ONNX_BUILD_TESTS "Build ONNX C++ APIs Tests" ON)
 option(ONNX_USE_LITE_PROTO "Use lite protobuf instead of full." OFF)
 option(ONNXIFI_ENABLE_EXT "Enable onnxifi extensions." OFF)
 if(NOT DEFINED ONNX_ML)
@@ -82,8 +82,10 @@ if(CMAKE_SYSTEM_NAME STREQUAL "AIX")
 endif()

 if(ONNX_BUILD_TESTS)
-  list(APPEND CMAKE_MODULE_PATH ${ONNX_ROOT}/cmake/external)
-  include(googletest)
+  find_package(GTest REQUIRED)
+  if(NOT GTest_FOUND)
+    message(FATAL_ERROR "cannot find googletest")
+  endif()
 endif()

 if((ONNX_USE_LITE_PROTO AND TARGET protobuf::libprotobuf-lite) OR ((NOT ONNX_USE_LITE_PROTO) AND TARGET protobuf::libprotobuf))
diff --git a/cmake/unittest.cmake b/cmake/unittest.cmake
index e29a93ff..ae146390 100644
--- a/cmake/unittest.cmake
+++ b/cmake/unittest.cmake
@@ -6,8 +6,8 @@ include(${ONNX_ROOT}/cmake/Utils.cmake)

 find_package(Threads)

-set(${UT_NAME}_libs ${googletest_STATIC_LIBRARIES})
-set(${ONNXIFI_TEST_DRIVER}_libs ${googletest_STATIC_LIBRARIES})
+set(${UT_NAME}_libs ${GTEST_LIBRARIES})
+set(${ONNXIFI_TEST_DRIVER}_libs ${GTEST_LIBRARIES})

 list(APPEND ${UT_NAME}_libs onnx)
 list(APPEND ${UT_NAME}_libs onnx_proto)
@@ -31,10 +31,10 @@ function(AddTest)
   list(REMOVE_DUPLICATES _UT_SOURCES)

   add_executable(${_UT_TARGET} ${_UT_SOURCES})
-  add_dependencies(${_UT_TARGET} onnx onnx_proto googletest)
+  add_dependencies(${_UT_TARGET} onnx onnx_proto)

   target_include_directories(${_UT_TARGET}
-                             PUBLIC ${googletest_INCLUDE_DIRS}
+                             PUBLIC ${GTEST_INCLUDE_DIRS}
                                     ${ONNX_INCLUDE_DIRS}
                                     ${PROTOBUF_INCLUDE_DIRS}
                                     ${ONNX_ROOT}
09929fa0860e17aa15de4'>pam.scm</a></div><div class='content'><table class='list nowrap'><tr class='nohover'><th class='left'>Age</th><th class='left'>Commit message (<a href='/guix/log/gnu/tests/pam.scm?id=0be51fe03bf2b8f3ef009929fa0860e17aa15de4&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>
<tr><td><span title='2023-08-15 23:30:43 +0200'>2023-08-15</span></td><td><a href='/guix/commit/gnu/tests/pam.scm?id=465c328c82345fcd87fcbc7f1a538be009894601'>tests: pam-limits: Confirm actual ulimits are installed.</a><span class='msg-avail'>...<span class='msg-tooltip'>This revised system test is superior to the one accepted when #61744 was
closed because it confirms whether the configured limits are actually being
enforced upon login.

The previous test merely validated the serialization of one particular config
in the config file.

* gnu/tests/pam.scm (pam-limits-service): Revise test to confirm limits on
login.
(%test-pam-limits)[description]: Update.
(%test-pam-limits-deprecated): Remove.

Signed-off-by: Ludovic Courtès &lt;ludo@gnu.org&gt;
</span></span></td><td>Felix Lechner</td></tr>
<tr><td><span title='2023-05-06 17:12:45 +0200'>2023-05-06</span></td><td><a href='/guix/commit/gnu/tests/pam.scm?id=f51888272558d98cf5c196b93fb6c499056fbf6c'>tests: Add missing module imports for marionette-evaluated code.</a><span class='msg-avail'>...<span class='msg-tooltip'>This missing imports became apparent with commit
a09c7da8f8d8e732f969cf0a09aaa78f87032ab1, which runs the marionette
service in a fresh Guile process with fewer imports.

* gnu/tests/databases.scm (run-postgresql-test, run-timescaledb-test)
(run-mysql-test): Add missing module imports for code passed to
'marionette-eval'.
* gnu/tests/docker.scm (run-docker-test, run-docker-system-test): Likewise.
* gnu/tests/mail.scm (run-dovecot-test, run-getmail-test): Likewise.
* gnu/tests/monitoring.scm (run-zabbix-server-test): Likewise.
* gnu/tests/pam.scm (run-test-pam-limits): Likewise.
* gnu/tests/reconfigure.scm (run-switch-to-system-test)
(run-install-bootloader-test): Likewise.
* gnu/tests/security-token.scm (run-pcscd-test): Likewise.
* gnu/tests/install.scm (gui-test-program): Likewise.
* gnu/tests/telephony.scm (run-jami-test): Add modules to
the #:imported-modules argument of 'marionette-operating-system'.
[test]: Remove them from 'with-imported-modules'; remove
'with-extensions'.  Add "d-bus tooling loaded" test to set up %load-path
and %load-compiled-path so the marionette process can find
guile-ac-d-bus and guile-packrat.
</span></span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2023-03-30 23:18:16 +0200'>2023-03-30</span></td><td><a href='/guix/commit/gnu/tests/pam.scm?id=6d0ad930206dccf382ec65c6504df51b5c798a34'>services: pam-limits-service-type: Deprecate file-like object support in favo...</a><span class='msg-avail'>...<span class='msg-tooltip'>* doc/guix.texi (Base Services): Document it.
* gnu/local.mk: Register test.
* gnu/services/base.scm (pam-limits-service-type): Accept both lists and
file-like objects. Deprecate file-like object support.
* gnu/tests/pam.scm: New file.

Signed-off-by: Ludovic Courtès &lt;ludo@gnu.org&gt;
</span></span></td><td>Bruno Victal</td></tr>