Merge pull request #3571 from JacksonM8/issue_3570

Issue 3570 (CMake Policy violations on MSVC)

CMakeLists.txt

@@ -261,7 +261,7 @@ IF ((CMAKE_C_COMPILER_ID MATCHES "GNU") AND NOT CMAKE_COMPILER_IS_MINGW)
   ENDIF()
 ELSEIF(MSVC)
   # enable multi-core compilation with MSVC
-  IF( "${CMAKE_CXX_COMPILER_ID}" MATCHES "Clang" ) # clang-cl
+  IF(CMAKE_CXX_COMPILER_ID MATCHES "Clang" ) # clang-cl
     ADD_COMPILE_OPTIONS(/bigobj /W4 /WX )
   ELSE() # msvc
     ADD_COMPILE_OPTIONS(/MP /bigobj /W4 /WX)
@@ -271,7 +271,7 @@ ELSEIF(MSVC)
     ADD_COMPILE_OPTIONS(/wd4351)
   ENDIF()
   SET(CMAKE_CXX_FLAGS_DEBUG "${CMAKE_CXX_FLAGS_DEBUG} /D_DEBUG /Zi /Od")
-ELSEIF ( "${CMAKE_CXX_COMPILER_ID}" MATCHES "Clang" )
+ELSEIF (CMAKE_CXX_COMPILER_ID MATCHES "Clang" )
   IF(NOT ASSIMP_HUNTER_ENABLED)
     SET(CMAKE_CXX_STANDARD 11)
     SET(CMAKE_POSITION_INDEPENDENT_CODE ON)

test/CMakeLists.txt

@@ -220,7 +220,7 @@ if(ASSIMP_HUNTER_ENABLED)
     find_package(GTest CONFIG REQUIRED)
     target_link_libraries(unit GTest::gtest_main GTest::gmock)
 else()
-    target_sources(unit PUBLIC ../contrib/gtest/src/gtest-all.cc)
+    target_sources(unit PUBLIC ${Assimp_SOURCE_DIR}/contrib/gtest/src/gtest-all.cc)
 endif()
 
 TARGET_USE_COMMON_OUTPUT_DIRECTORY(unit)