test

# CMake strategy to find the C library libyaml using multiple approaches:

# The goal is to set the final target to 'YAML::YAML' in all successful cases.

# - Find libyaml

# Find the native Yaml headers and libraries.

#

#  YAML_INCLUDE_DIRS - where to find yaml.h

#  YAML_LIBRARIES    - List of libraries when using libyaml

#  YAML_FOUND        - True if libyaml is found.

#

# 1. CONFIG Package Search (e.g., vcpkg, Conan)

# Check for both 'yaml' (common vcpkg) and 'LibYAML' (sometimes provided by system)

find_package(yaml CONFIG QUIET)

find_package(LibYAML CONFIG QUIET)

find_path(YAML_INCLUDE_DIR yaml.h PATH_SUFFIXES yaml)

find_library(YAML_LIBRARY NAMES yaml)

# Determine if the CONFIG search succeeded

if(yaml_FOUND OR LibYAML_FOUND)

    message(STATUS "Found libyaml via CONFIG.")

# handle the QUIET and REQUIRED arguments and

# set YAML_FOUND to TRUE if all variables are non-zero

include(FindPackageHandleStandardArgs)

find_package_handle_standard_args(YAML DEFAULT_MSG YAML_LIBRARY YAML_INCLUDE_DIR)

    # --- ENSURE UPPERCASE ALIAS ---

    # Most vcpkg/Conan config files define 'yaml::yaml' (lowercase).

    # We must ensure the required 'YAML::YAML' (uppercase) target exists.

# Copy the results to the output variables and target.

if(YAML_FOUND)

  set(YAML_LIBRARIES ${YAML_LIBRARY})

  set(YAML_INCLUDE_DIRS ${YAML_INCLUDE_DIR})

    # 1. If the lowercase target exists, create the uppercase alias

    if(TARGET yaml::yaml AND NOT TARGET YAML::YAML)

        add_library(YAML::YAML ALIAS yaml::yaml)

        message(STATUS "Created ALIAS target YAML::YAML -> yaml::yaml.")

    # 2. Check if the uppercase target already exists (e.g., from LibYAML config)

    elseif(TARGET LibYAML::LibYAML AND NOT TARGET YAML::YAML)

        add_library(YAML::YAML ALIAS LibYAML::LibYAML)

        message(STATUS "Created ALIAS target YAML::YAML -> LibYAML::LibYAML.")

    # 3. Handle the case where the CONFIG script already defined YAML::YAML

    elseif(TARGET YAML::YAML)

        # Target already exists, no action needed.

    else()

        message(FATAL_ERROR "libyaml found via CONFIG, but no recognizable target (yaml::yaml or YAML::YAML) was created.")

    endif()

# Fallback to Manual Search

else() 

    # 2. pkg-config Search (Common on Linux/MSYS)

    find_package(PkgConfig QUIET)

    if(PkgConfig_FOUND)

        pkg_check_modules(LIBYAML QUIET yaml-0.1)

    endif()

    # Determine if a manual search is necessary

    if(NOT LIBYAML_FOUND)

        # 3. Classic CMake Search (Manual Fallback)

        find_path(LIBYAML_INCLUDE_DIR yaml.h

                     HINTS $ENV{LIBYAML_ROOT} ${CMAKE_PREFIX_PATH}

                     PATH_SUFFIXES include include/yaml

                     )

        # Note: 'HINTS ... "${CMAKE_PREFIX_PATH}"' is redundant with PATH_SUFFIXES 'lib' and CMAKE_PREFIX_PATH

        find_library(LIBYAML_LIBRARY NAMES yaml libyaml

                     HINTS $ENV{LIBYAML_ROOT} ${CMAKE_PREFIX_PATH} 

                     PATH_SUFFIXES lib

                     )

        # 4. Check results from the classic search

        if(NOT (LIBYAML_INCLUDE_DIR AND LIBYAML_LIBRARY))

            message(FATAL_ERROR "libyaml (C) not found. Please set LIBYAML_ROOT or install it.")

        endif()

    endif()

    # --- UNIFIED TARGET CREATION (For pkg-config and Classic) ---

    # This block runs only if we successfully found it manually or via pkg-config

    # 5. Create the final modern target 'YAML::YAML' (Uppercase)

    if(NOT TARGET YAML::YAML) # Only create if not already handled by CONFIG (unlikely here, but safe)

        add_library(YAML::YAML INTERFACE IMPORTED) 

        if(LIBYAML_FOUND) # pkg-config results

            target_include_directories(YAML::YAML INTERFACE ${LIBYAML_INCLUDE_DIRS})

            target_link_libraries(YAML::YAML INTERFACE ${LIBYAML_LIBRARIES})

        else() # Classic Search results

            target_include_directories(YAML::YAML INTERFACE ${LIBYAML_INCLUDE_DIR})

            target_link_libraries(YAML::YAML INTERFACE ${LIBYAML_LIBRARY})

        endif()

  if(NOT TARGET Yaml::Yaml)

    add_library(Yaml::Yaml UNKNOWN IMPORTED)

    set_target_properties(Yaml::Yaml PROPERTIES

      IMPORTED_LOCATION "${YAML_LIBRARY}"

      INTERFACE_INCLUDE_DIRECTORIES "${YAML_INCLUDE_DIR}")

  endif()

endif()

# In your custom FindYAML logic, *immediately* after find_package(yaml CONFIG QUIET)

if(yaml_FOUND)

    # Check if the CONFIG file created the lowercase target

    if(TARGET yaml::yaml AND NOT TARGET YAML::YAML)

        # Create the ALIAS that backends/CMakeLists.txt needs

        add_library(YAML::YAML ALIAS yaml::yaml) 

        message(STATUS "SUCCESS: Created ALIAS target YAML::YAML -> yaml::yaml.")

    # ... (Other checks for LibYAML::LibYAML, etc.) ...

    elseif(NOT TARGET YAML::YAML)

        # If the CONFIG search found the package but didn't create a target we recognize, 

        # the build will fail. Log this for debugging.

        message(WARNING "libyaml found via CONFIG, but failed to create or find target YAML::YAML.")

    endif()

endif()

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mark_as_advanced(YAML_INCLUDE_DIR YAML_LIBRARY)

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