[script] install gtest and gmock (#11358)

.github/workflows/unit.yml

@@ -77,7 +77,7 @@ jobs:
     - name: Bootstrap
       run: |
         sudo apt-get update
-        sudo apt-get --no-install-recommends install -y ninja-build lcov
+        sudo apt-get --no-install-recommends install -y ninja-build lcov libgtest-dev libgmock-dev
     - name: Build Simulation
       run: ./script/cmake-build simulation -DOT_BUILD_GTEST=ON -DOT_BORDER_ROUTING=ON -DOT_BORDER_ROUTING_DHCP6_PD=ON
     - name: Test Simulation

script/bootstrap

@@ -56,7 +56,7 @@ install_packages_apt()
 
     # apt-get update and install dependencies
     sudo apt-get update
-    sudo apt-get --no-install-recommends install -y g++ lsb-release cmake ninja-build shellcheck
+    sudo apt-get --no-install-recommends install -y g++ lsb-release cmake ninja-build shellcheck libgtest-dev libgmock-dev
 
     echo 'Installing GNU Arm Embedded Toolchain...'
 

tests/gtest/CMakeLists.txt

@@ -29,19 +29,12 @@
 cmake_minimum_required(VERSION 3.14)
 project(openthread-gtest)
 
+find_package(GTest CONFIG REQUIRED COMPONENTS GTest GMock Main)
+
 # GoogleTest requires at least C++14
 set(CMAKE_CXX_STANDARD 14)
 set(CMAKE_CXX_STANDARD_REQUIRED ON)
 
-include(FetchContent)
-FetchContent_Declare(
-    googletest
-    URL https://github.com/google/googletest/archive/03597a01ee50ed33e9dfd640b249b4be3799d395.zip
-)
-# For Windows: Prevent overriding the parent project's compiler/linker settings
-set(gtest_force_shared_crt ON CACHE BOOL "" FORCE)
-FetchContent_MakeAvailable(googletest)
-
 include(GoogleTest)
 
 add_library(ot-fake-platform
@@ -62,7 +55,9 @@ add_executable(ot-ftd-gtest
 )
 target_link_libraries(ot-ftd-gtest
     ot-fake-ftd
-    GTest::gmock_main
+    GTest::gtest
+    GTest::gmock
+    GTest::gtest_main
 )
 gtest_discover_tests(ot-ftd-gtest)
 
@@ -82,7 +77,9 @@ add_executable(ot-radio-spinel-rcp-gtest
 )
 target_link_libraries(ot-radio-spinel-rcp-gtest
     ot-fake-rcp
-    GTest::gmock_main
+    GTest::gtest
+    GTest::gmock
+    GTest::gtest_main
 )
 
 gtest_discover_tests(ot-radio-spinel-rcp-gtest)