[TEST] Use gtest_discover_tests to prevent false-positive test passes

CHANGELOG.md

@@ -15,6 +15,10 @@ Increment the:
 
 ## [Unreleased]
 
+* [TEST] Replace `gtest_add_tests()` with `gtest_discover_tests()` to prevent
+  false-positive test passes for tests compiled out by preprocessor conditionals.
+  [#4341](https://github.com/open-telemetry/opentelemetry-cpp/issues/4341)
+
 ## [1.30.0] 2026-10-22
 
 This release contains:

api/test/baggage/CMakeLists.txt

@@ -7,10 +7,7 @@ foreach(testname baggage_test)
   add_executable(${testname} "${testname}.cc")
   target_link_libraries(${testname} ${GTEST_BOTH_LIBRARIES}
                         ${CMAKE_THREAD_LIBS_INIT} opentelemetry_api)
-  gtest_add_tests(
-    TARGET ${testname}
-    TEST_PREFIX baggage.
-    TEST_LIST ${testname})
+  gtest_discover_tests(${testname} TEST_PREFIX baggage.)
 endforeach()
 
 if(OTELCPP_WITH_BENCHMARK)

api/test/baggage/propagation/CMakeLists.txt

@@ -5,8 +5,5 @@ foreach(testname baggage_propagator_test)
   add_executable(${testname} "${testname}.cc")
   target_link_libraries(${testname} ${GTEST_BOTH_LIBRARIES}
                         ${CMAKE_THREAD_LIBS_INIT} opentelemetry_api)
-  gtest_add_tests(
-    TARGET ${testname}
-    TEST_PREFIX baggage.
-    TEST_LIST ${testname})
+  gtest_discover_tests(${testname} TEST_PREFIX baggage.)
 endforeach()

api/test/common/CMakeLists.txt

@@ -7,10 +7,7 @@ foreach(testname ascii_test kv_properties_test string_util_test)
   add_executable(${testname} "${testname}.cc")
   target_link_libraries(${testname} ${GTEST_BOTH_LIBRARIES}
                         ${CMAKE_THREAD_LIBS_INIT} opentelemetry_api)
-  gtest_add_tests(
-    TARGET ${testname}
-    TEST_PREFIX common.
-    TEST_LIST ${testname})
+  gtest_discover_tests(${testname} TEST_PREFIX common.)
 endforeach()
 
 if(OTELCPP_WITH_BENCHMARK)

api/test/context/CMakeLists.txt

@@ -9,8 +9,5 @@ foreach(testname context_test runtime_context_test)
   add_executable(${testname} "${testname}.cc")
   target_link_libraries(${testname} ${GTEST_BOTH_LIBRARIES}
                         ${CMAKE_THREAD_LIBS_INIT} opentelemetry_api)
-  gtest_add_tests(
-    TARGET ${testname}
-    TEST_PREFIX context.
-    TEST_LIST ${testname})
+  gtest_discover_tests(${testname} TEST_PREFIX context.)
 endforeach()

api/test/context/propagation/CMakeLists.txt

@@ -6,8 +6,5 @@ foreach(testname composite_propagator_test environment_carrier_test
   add_executable(${testname} "${testname}.cc")
   target_link_libraries(${testname} ${GTEST_BOTH_LIBRARIES}
                         ${CMAKE_THREAD_LIBS_INIT} opentelemetry_api)
-  gtest_add_tests(
-    TARGET ${testname}
-    TEST_PREFIX trace.
-    TEST_LIST ${testname})
+  gtest_discover_tests(${testname} TEST_PREFIX trace.)
 endforeach()

api/test/core/CMakeLists.txt

@@ -6,15 +6,9 @@ include(GoogleTest)
 add_executable(timestamp_test timestamp_test.cc)
 target_link_libraries(timestamp_test ${GTEST_BOTH_LIBRARIES}
                       ${CMAKE_THREAD_LIBS_INIT} opentelemetry_api)
-gtest_add_tests(
-  TARGET timestamp_test
-  TEST_PREFIX trace.
-  TEST_LIST timestamp_test)
+gtest_discover_tests(timestamp_test TEST_PREFIX trace.)
 
 add_executable(version_test version_test.cc)
 target_link_libraries(version_test ${GTEST_BOTH_LIBRARIES}
                       ${CMAKE_THREAD_LIBS_INIT} opentelemetry_api)
-gtest_add_tests(
-  TARGET version_test
-  TEST_PREFIX version.
-  TEST_LIST version_test)
+gtest_discover_tests(version_test TEST_PREFIX version.)

api/test/logs/CMakeLists.txt

@@ -5,10 +5,7 @@ foreach(testname provider_test logger_test)
   add_executable(logs_api_${testname} "${testname}.cc")
   target_link_libraries(logs_api_${testname} ${GTEST_BOTH_LIBRARIES}
                         ${CMAKE_THREAD_LIBS_INIT} opentelemetry_api)
-  gtest_add_tests(
-    TARGET logs_api_${testname}
-    TEST_PREFIX logs.
-    TEST_LIST logs_api_${testname})
+  gtest_discover_tests(logs_api_${testname} TEST_PREFIX logs.)
 endforeach()
 
 if(OTELCPP_WITH_BENCHMARK)

api/test/metrics/CMakeLists.txt

@@ -5,8 +5,5 @@ foreach(testname meter_provider_test noop_sync_instrument_test)
   add_executable(${testname} "${testname}.cc")
   target_link_libraries(${testname} ${GTEST_BOTH_LIBRARIES}
                         ${CMAKE_THREAD_LIBS_INIT} opentelemetry_api)
-  gtest_add_tests(
-    TARGET ${testname}
-    TEST_PREFIX metrics_new.
-    TEST_LIST ${testname})
+  gtest_discover_tests(${testname} TEST_PREFIX metrics_new.)
 endforeach()

api/test/nostd/CMakeLists.txt

@@ -15,8 +15,5 @@ foreach(
   add_executable(${testname} "${testname}.cc")
   target_link_libraries(${testname} ${GTEST_BOTH_LIBRARIES}
                         ${CMAKE_THREAD_LIBS_INIT} opentelemetry_api)
-  gtest_add_tests(
-    TARGET ${testname}
-    TEST_PREFIX nostd.
-    TEST_LIST ${testname})
+  gtest_discover_tests(${testname} TEST_PREFIX nostd.)
 endforeach()

api/test/singleton/CMakeLists.txt

@@ -49,7 +49,4 @@ target_link_libraries(
   ${CMAKE_DL_LIBS}
   opentelemetry_api)
 
-gtest_add_tests(
-  TARGET singleton_test
-  TEST_PREFIX singleton.
-  TEST_LIST singleton_test)
+gtest_discover_tests(singleton_test TEST_PREFIX singleton.)

api/test/trace/CMakeLists.txt

@@ -19,10 +19,7 @@ foreach(
   add_executable(api_${testname} "${testname}.cc")
   target_link_libraries(api_${testname} ${GTEST_BOTH_LIBRARIES}
                         ${CMAKE_THREAD_LIBS_INIT} opentelemetry_api)
-  gtest_add_tests(
-    TARGET api_${testname}
-    TEST_PREFIX trace.
-    TEST_LIST api_${testname})
+  gtest_discover_tests(api_${testname} TEST_PREFIX trace.)
 endforeach()
 
 if(OTELCPP_WITH_BENCHMARK)

api/test/trace/propagation/CMakeLists.txt

@@ -8,10 +8,7 @@ foreach(testname http_text_format_test b3_propagation_test
   add_executable(${testname} "${testname}.cc")
   target_link_libraries(${testname} ${GTEST_BOTH_LIBRARIES}
                         ${CMAKE_THREAD_LIBS_INIT} opentelemetry_api)
-  gtest_add_tests(
-    TARGET ${testname}
-    TEST_PREFIX trace.
-    TEST_LIST ${testname})
+  gtest_discover_tests(${testname} TEST_PREFIX trace.)
 endforeach()
 
 if(OTELCPP_WITH_BENCHMARK)

api/test/trace/propagation/detail/CMakeLists.txt

@@ -5,8 +5,5 @@ foreach(testname hex_test string_test)
   add_executable(${testname} "${testname}.cc")
   target_link_libraries(${testname} ${GTEST_BOTH_LIBRARIES}
                         ${CMAKE_THREAD_LIBS_INIT} opentelemetry_api)
-  gtest_add_tests(
-    TARGET ${testname}
-    TEST_PREFIX trace.
-    TEST_LIST ${testname})
+  gtest_discover_tests(${testname} TEST_PREFIX trace.)
 endforeach()

docs/google-test.md

@@ -229,7 +229,7 @@ foreach(
   target_link_libraries(
     ${testname} ${GTEST_BOTH_LIBRARIES} ${CMAKE_THREAD_LIBS_INIT}
     opentelemetry_common opentelemetry_trace)
-  gtest_add_tests(TARGET ${testname} TEST_PREFIX trace. TEST_LIST ${testname})
+  gtest_discover_tests(${testname} TEST_PREFIX trace.)
 endforeach()
 
 add_executable(sampler_benchmark sampler_benchmark.cc)
@@ -238,6 +238,8 @@ target_link_libraries(sampler_benchmark benchmark::benchmark
 
 ```
 
+**Note:** The project uses `gtest_discover_tests()` instead of `gtest_add_tests()` to ensure that tests compiled out by preprocessor conditionals are not registered in CTest. This prevents false-positive test passes for tests that were never actually run.
+
 This is how a `CMakeLists.txt` file will be written with the purpose of unit
 testing. After writing a unit test, navigate to the `CMakeLists.txt` file for
 that subdirectory and add the test name to the list of test names in

exporters/elasticsearch/CMakeLists.txt

@@ -54,8 +54,5 @@ if(OTELCPP_BUILD_TESTING)
     es_log_record_exporter_test ${GTEST_BOTH_LIBRARIES}
     ${CMAKE_THREAD_LIBS_INIT} opentelemetry_exporter_elasticsearch_logs)
 
-  gtest_add_tests(
-    TARGET es_log_record_exporter_test
-    TEST_PREFIX exporter.
-    TEST_LIST es_log_record_exporter_test)
+  gtest_discover_tests(es_log_record_exporter_test TEST_PREFIX exporter.)
 endif() # OTELCPP_BUILD_TESTING

exporters/etw/CMakeLists.txt

@@ -68,29 +68,10 @@ if(OTELCPP_BUILD_TESTING)
       opentelemetry_exporter_etw ${CMAKE_THREAD_LIBS_INIT})
   endif()
 
-  gtest_add_tests(
-    TARGET etw_provider_test
-    TEST_PREFIX exporter.
-    TEST_LIST etw_provider_test)
-  gtest_add_tests(
-    TARGET etw_tracer_test
-    TEST_PREFIX exporter.
-    TEST_LIST etw_tracer_test)
-  gtest_add_tests(
-    TARGET etw_logger_test
-    TEST_PREFIX exporter.
-    TEST_LIST etw_logger_test)
-  gtest_add_tests(
-    TARGET etw_properties_test
-    TEST_PREFIX exporter.
-    TEST_LIST etw_properties_test)
-  gtest_add_tests(
-    TARGET etw_tracer_test_enable_env_properties
-    TEST_PREFIX exporter.with_env_properties.
-    TEST_LIST etw_tracer_test_enable_env_properties)
-  gtest_add_tests(
-    TARGET etw_logger_test_enable_env_properties
-    TEST_PREFIX exporter.with_env_properties.
-    TEST_LIST etw_logger_test_enable_env_properties)
+  gtest_discover_tests(etw_provider_test TEST_PREFIX exporter.)
+  gtest_discover_tests(etw_tracer_test TEST_PREFIX exporter.)
+  gtest_discover_tests(etw_logger_test TEST_PREFIX exporter.)
+  gtest_discover_tests(etw_tracer_test_enable_env_properties TEST_PREFIX exporter.with_env_properties.)
+  gtest_discover_tests(etw_logger_test_enable_env_properties TEST_PREFIX exporter.with_env_properties.)
 
 endif() # OTELCPP_BUILD_TESTING

exporters/memory/CMakeLists.txt

@@ -86,20 +86,8 @@ if(OTELCPP_BUILD_TESTING)
     ${CMAKE_THREAD_LIBS_INIT} opentelemetry_exporter_in_memory_metric
     opentelemetry_resources)
 
-  gtest_add_tests(
-    TARGET in_memory_span_data_test
-    TEST_PREFIX exporter.
-    TEST_LIST in_memory_span_data_test)
-  gtest_add_tests(
-    TARGET in_memory_span_exporter_test
-    TEST_PREFIX exporter.
-    TEST_LIST in_memory_span_exporter_test)
-  gtest_add_tests(
-    TARGET in_memory_metric_data_test
-    TEST_PREFIX exporter.
-    TEST_LIST in_memory_metric_data_test)
-  gtest_add_tests(
-    TARGET in_memory_metric_exporter_test
-    TEST_PREFIX exporter.
-    TEST_LIST in_memory_metric_exporter_test)
+  gtest_discover_tests(in_memory_span_data_test TEST_PREFIX exporter.)
+  gtest_discover_tests(in_memory_span_exporter_test TEST_PREFIX exporter.)
+  gtest_discover_tests(in_memory_metric_data_test TEST_PREFIX exporter.)
+  gtest_discover_tests(in_memory_metric_exporter_test TEST_PREFIX exporter.)
 endif()

exporters/ostream/CMakeLists.txt

@@ -28,10 +28,7 @@ if(OTELCPP_BUILD_TESTING)
   add_executable(ostream_span_test test/ostream_span_test.cc)
   target_link_libraries(ostream_span_test ${GTEST_BOTH_LIBRARIES}
                         opentelemetry_exporter_ostream_span)
-  gtest_add_tests(
-    TARGET ostream_span_test
-    TEST_PREFIX exporter.
-    TEST_LIST ostream_span_test)
+  gtest_discover_tests(ostream_span_test TEST_PREFIX exporter.)
 endif() # OTELCPP_BUILD_TESTING
 
 #
@@ -84,10 +81,7 @@ if(OTELCPP_BUILD_TESTING)
   target_link_libraries(
     ostream_metric_test ${GTEST_BOTH_LIBRARIES}
     opentelemetry_exporter_ostream_metrics opentelemetry_resources)
-  gtest_add_tests(
-    TARGET ostream_metric_test
-    TEST_PREFIX exporter.
-    TEST_LIST ostream_metric_test)
+  gtest_discover_tests(ostream_metric_test TEST_PREFIX exporter.)
 endif()
 
 #
@@ -134,10 +128,7 @@ if(OTELCPP_BUILD_TESTING)
   add_executable(ostream_log_test test/ostream_log_test.cc)
   target_link_libraries(ostream_log_test ${GTEST_BOTH_LIBRARIES}
                         opentelemetry_exporter_ostream_logs)
-  gtest_add_tests(
-    TARGET ostream_log_test
-    TEST_PREFIX exporter.
-    TEST_LIST ostream_log_test)
+  gtest_discover_tests(ostream_log_test TEST_PREFIX exporter.)
 endif()
 
 #