Skip install gtest when build with test

Signed-off-by: XuanYang-cn <xuan.yang@zilliz.com>

.gitignore

@@ -67,6 +67,8 @@ cwrapper_build
 **/.lint
 typescript
 **/.pytest_cache/
+.root
+gtags.conf
 
 # Delve generated file
 **/__debug_bin

internal/core/thirdparty/google_benchmark/CMakeLists.txt

@@ -1,4 +1,3 @@
-include(FetchContent)
 FetchContent_Declare(google_benchmark
     URL             https://github.com/google/benchmark/archive/v1.5.2.tar.gz
     URL_MD5         084b34aceaeac11a6607d35220ca2efa

internal/core/thirdparty/gtest/CMakeLists.txt

@@ -29,7 +29,17 @@ FetchContent_Declare(
         BINARY_DIR      ${CMAKE_CURRENT_BINARY_DIR}/googletest-build
         DOWNLOAD_DIR    ${THIRDPARTY_DOWNLOAD_PATH} )
 
-FetchContent_MakeAvailable(googletest)
+FetchContent_GetProperties( googletest )
+if ( NOT googletest_POPULATED )
+
+    FetchContent_Populate( googletest )
+
+    # Adding the following targets:
+    # gtest, gtest_main, gmock, gmock_main
+    add_subdirectory( ${googletest_SOURCE_DIR}
+                      ${googletest_BINARY_DIR}
+                      EXCLUDE_FROM_ALL )
+endif()
 # include(GoogleTest)
 
 # ****************************************************************

internal/core/unittest/CMakeLists.txt

@@ -55,3 +55,4 @@ target_link_libraries(all_tests
         )
 
 install (TARGETS all_tests DESTINATION unittest)
+install (TARGETS index_builder_test DESTINATION unittest)