create mrpt_data with example config files and small datasets for unit tests

Author: jlblancoc

modules/mrpt_common/cmake/mrpt_cmake_functions.cmake

@@ -665,7 +665,25 @@ function(mrpt_add_test)
       # Use relative paths for embedded files:
       target_compile_definitions(${MRPT_ADD_TEST_TARGET} PRIVATE CMAKE_UNITTEST_BASEDIR=".")
     endif()
-  
+
+    # Path to mrpt_data shared test data (config_files/, datasets/, tests/):
+    if (NOT DEFINED MRPT_DATA_SOURCE_DIR)
+      # Try to find it as a sibling module (colcon layout):
+      if (EXISTS "${CMAKE_SOURCE_DIR}/../mrpt_data")
+        get_filename_component(MRPT_DATA_SOURCE_DIR "${CMAKE_SOURCE_DIR}/../mrpt_data" ABSOLUTE)
+        set(MRPT_DATA_SOURCE_DIR "${MRPT_DATA_SOURCE_DIR}" CACHE PATH "Path to mrpt_data module")
+      else()
+        # Fallback: try installed package:
+        find_package(mrpt_data QUIET)
+        if (mrpt_data_FOUND)
+          set(MRPT_DATA_SOURCE_DIR "${mrpt_data_DATA_DIR}" CACHE PATH "Path to mrpt_data (installed)")
+        endif()
+      endif()
+    endif()
+    if (MRPT_DATA_SOURCE_DIR)
+      target_compile_definitions(${MRPT_ADD_TEST_TARGET} PRIVATE MRPT_DATA_DIR="${MRPT_DATA_SOURCE_DIR}")
+    endif()
+
     # Run it:
     #add_custom_target(run_${MRPT_ADD_TEST_TARGET} COMMAND $<TARGET_FILE:${MRPT_ADD_TEST_TARGET}>)
     add_test(${MRPT_ADD_TEST_TARGET}_build "${CMAKE_COMMAND}" --build ${CMAKE_CURRENT_BINARY_DIR} --target ${MRPT_ADD_TEST_TARGET})

modules/mrpt_common/common_headers/test_mrpt_common.h

@@ -15,4 +15,5 @@
 namespace mrpt
 {
 std::string UNITTEST_BASEDIR();
+std::string mrpt_data_dir();
 }

modules/mrpt_common/common_sources/mrpt_test_main.cpp

@@ -13,6 +13,14 @@
 
 std::string mrpt::UNITTEST_BASEDIR() { return CMAKE_UNITTEST_BASEDIR; }
 
+#ifdef MRPT_DATA_DIR
+static const std::string mrpt_data_dir_value = MRPT_DATA_DIR;
+#undef MRPT_DATA_DIR
+std::string mrpt::mrpt_data_dir() { return mrpt_data_dir_value; }
+#else
+std::string mrpt::mrpt_data_dir() { return CMAKE_UNITTEST_BASEDIR; }
+#endif
+
 int main(int argc, char** argv)
 {
 	testing::InitGoogleTest(&argc, argv);

modules/mrpt_data/CMakeLists.txt

@@ -0,0 +1,34 @@
+cmake_minimum_required(VERSION 3.16)
+project(mrpt_data LANGUAGES NONE)
+
+# This package ships no code, only data files for unit tests and
+# example configuration files.
+#
+# After find_package(mrpt_data), the following variable is defined:
+#   mrpt_data_DATA_DIR  - Absolute path to the installed data root directory
+#                         containing: config_files/, datasets/, tests/
+
+# Install data files preserving directory structure:
+install(DIRECTORY
+  config_files
+  datasets
+  tests
+  DESTINATION share/${PROJECT_NAME}
+)
+
+# Generate and install a CMake config file so that downstream packages
+# can do find_package(mrpt_data) and get mrpt_data_DATA_DIR:
+include(CMakePackageConfigHelpers)
+
+# The config file will compute the data dir relative to its own location.
+file(WRITE "${CMAKE_CURRENT_BINARY_DIR}/mrpt_dataConfig.cmake"
+"# mrpt_data CMake config file
+# Provides: mrpt_data_DATA_DIR
+get_filename_component(_mrpt_data_CONFIG_DIR \"\${CMAKE_CURRENT_LIST_DIR}\" ABSOLUTE)
+get_filename_component(mrpt_data_DATA_DIR \"\${_mrpt_data_CONFIG_DIR}/../../../share/mrpt_data\" ABSOLUTE)
+unset(_mrpt_data_CONFIG_DIR)
+")
+
+install(FILES "${CMAKE_CURRENT_BINARY_DIR}/mrpt_dataConfig.cmake"
+  DESTINATION lib/cmake/${PROJECT_NAME}
+)