Fix static builds and optimize test compilation

Signed-off-by: Addisu Z. Taddese <addisu@openrobotics.org>

src/CMakeLists.txt

@@ -5,10 +5,9 @@ ign_get_libsources_and_unittests(sources gtest_sources)
 # Add the source file auto-generated into the build folder from sdf/CMakeLists.txt
 list(APPEND sources EmbeddedSdf.cc)
 
-# Use interface library to deduplicate cmake logic for URDF linking
-add_library(using_parser_urdf INTERFACE)
+# When using the internal URDF parser, we build its sources with the core library
 if (USE_INTERNAL_URDF)
-  set(sources ${sources}
+  set(urdf_internal_sources
     urdf/urdf_parser/model.cpp
     urdf/urdf_parser/link.cpp
     urdf/urdf_parser/joint.cpp
@@ -17,14 +16,7 @@ if (USE_INTERNAL_URDF)
     urdf/urdf_parser/urdf_model_state.cpp
     urdf/urdf_parser/urdf_sensor.cpp
     urdf/urdf_parser/world.cpp)
-  target_include_directories(using_parser_urdf INTERFACE
-    ${CMAKE_CURRENT_SOURCE_DIR}/urdf)
-  if (WIN32)
-    target_compile_definitions(using_parser_urdf INTERFACE -D_USE_MATH_DEFINES)
-  endif()
-else()
-  target_link_libraries(using_parser_urdf INTERFACE
-    IgnURDFDOM::IgnURDFDOM)
+  set(sources ${sources} ${urdf_internal_sources})
 endif()
 
 ign_create_core_library(SOURCES ${sources}
@@ -37,8 +29,18 @@ target_link_libraries(${PROJECT_LIBRARY_TARGET_NAME}
     ignition-math${IGN_MATH_VER}::ignition-math${IGN_MATH_VER}
     ignition-utils${IGN_UTILS_VER}::ignition-utils${IGN_UTILS_VER}
   PRIVATE
-    TINYXML2::TINYXML2
-    using_parser_urdf)
+    TINYXML2::TINYXML2)
+
+  if (USE_INTERNAL_URDF)
+    target_include_directories(${PROJECT_LIBRARY_TARGET_NAME} PRIVATE
+      ${CMAKE_CURRENT_SOURCE_DIR}/urdf)
+    if (WIN32)
+      target_compile_definitions(${PROJECT_LIBRARY_TARGET_NAME} PRIVATE -D_USE_MATH_DEFINES)
+    endif()
+  else()
+    target_link_libraries(${PROJECT_LIBRARY_TARGET_NAME} PRIVATE
+      IgnURDFDOM::IgnURDFDOM)
+  endif()
 
 if (WIN32)
   target_compile_definitions(${PROJECT_LIBRARY_TARGET_NAME} PRIVATE URDFDOM_STATIC)
@@ -55,43 +57,7 @@ if (BUILD_TESTING)
     list(REMOVE_ITEM gtest_sources ign_TEST.cc)
   endif()
 
-  # Skip tests that don't work on Windows
-  if (WIN32)
-    list(REMOVE_ITEM gtest_sources Converter_TEST.cc)
-    list(REMOVE_ITEM gtest_sources FrameSemantics_TEST.cc)
-    list(REMOVE_ITEM gtest_sources ParamPassing_TEST.cc)
-    list(REMOVE_ITEM gtest_sources Utils_TEST.cc)
-    list(REMOVE_ITEM gtest_sources XmlUtils_TEST.cc)
-    list(REMOVE_ITEM gtest_sources parser_urdf_TEST.cc)
-  endif()
-
-  ign_build_tests(
-    TYPE UNIT
-    SOURCES ${gtest_sources}
-    INCLUDE_DIRS
-      ${CMAKE_CURRENT_SOURCE_DIR}
-      ${PROJECT_SOURCE_DIR}/test
-  )
-
-  if (TARGET UNIT_Converter_TEST)
-    target_link_libraries(UNIT_Converter_TEST
-      TINYXML2::TINYXML2)
-    target_sources(UNIT_Converter_TEST PRIVATE
-      Converter.cc
-      EmbeddedSdf.cc
-      XmlUtils.cc)
-  endif()
-
-  if (TARGET UNIT_FrameSemantics_TEST)
-    target_sources(UNIT_FrameSemantics_TEST PRIVATE FrameSemantics.cc Utils.cc)
-    target_link_libraries(UNIT_FrameSemantics_TEST TINYXML2::TINYXML2)
-  endif()
-
-  if (TARGET UNIT_ParamPassing_TEST)
-    target_link_libraries(UNIT_ParamPassing_TEST
-      TINYXML2::TINYXML2
-      using_parser_urdf)
-    target_sources(UNIT_ParamPassing_TEST PRIVATE
+  add_library(library_for_tests STATIC
       Converter.cc
       EmbeddedSdf.cc
       FrameSemantics.cc
@@ -100,29 +66,45 @@ if (BUILD_TESTING)
       Utils.cc
       XmlUtils.cc
       parser.cc
-      parser_urdf.cc)
-  endif()
+      parser_urdf.cc
+  )
 
-  if (TARGET UNIT_Utils_TEST)
-    target_sources(UNIT_Utils_TEST PRIVATE Utils.cc)
-    target_link_libraries(UNIT_Utils_TEST TINYXML2::TINYXML2)
+  if (USE_INTERNAL_URDF)
+    target_sources(library_for_tests PRIVATE ${urdf_internal_sources})
   endif()
 
-  if (TARGET UNIT_XmlUtils_TEST)
-    target_link_libraries(UNIT_XmlUtils_TEST
-      TINYXML2::TINYXML2)
-    target_sources(UNIT_XmlUtils_TEST PRIVATE XmlUtils.cc)
-  endif()
+  # MSVC will fail saying there are some symbols are defined multiple times. This is true
+  # since some of the symbols in the static library are public symbols and will also be in the
+  # dynamic library (core library). But this is okay since they will be exactly the same definitions,
+  # so here, we set `/FORCE:MULTIPLE` to disable the error.
+  target_link_options(library_for_tests PUBLIC $<$<CXX_COMPILER_ID:MSVC>:/FORCE:MULTIPLE>)
+
+  target_link_libraries(library_for_tests PUBLIC
+    ${PROJECT_LIBRARY_TARGET_NAME}
+    # Also link against the privately linked libraries of the core library
+    $<TARGET_PROPERTY:${PROJECT_LIBRARY_TARGET_NAME},LINK_LIBRARIES>
+  )
+
+  # Use the private include flags from the core library
+  target_include_directories(library_for_tests PUBLIC
+    $<TARGET_PROPERTY:${PROJECT_LIBRARY_TARGET_NAME},INCLUDE_DIRECTORIES>
+  )
+
+  # Use the private comopile flags from the core library
+  target_compile_definitions(library_for_tests PUBLIC
+    $<TARGET_PROPERTY:${PROJECT_LIBRARY_TARGET_NAME},COMPILE_DEFINITIONS>
+  )
+
+  ign_build_tests(
+    TYPE UNIT
+    SOURCES ${gtest_sources}
+    INCLUDE_DIRS
+      ${CMAKE_CURRENT_SOURCE_DIR}
+      ${PROJECT_SOURCE_DIR}/test
+    LIB_DEPS
+      library_for_tests
+  )
 
-  if (TARGET UNIT_parser_urdf_TEST)
-    target_link_libraries(UNIT_parser_urdf_TEST
-      TINYXML2::TINYXML2
-      using_parser_urdf)
-    target_sources(UNIT_parser_urdf_TEST PRIVATE
-      SDFExtension.cc
-      XmlUtils.cc
-      parser_urdf.cc)
-  endif()
 endif()
 
 if(NOT WIN32)