Enable target aliasing on dependencies that are brought in from the system / FORCE_SYSTEM_<content-name>

cmake/modules/hfc_cmake_targets_cache.cmake

@@ -106,6 +106,15 @@ function(hfc_cmake_targets_cache_isolated)
   set(HERMETIC_FETCHCONTENT_CMAKE_ADDITIONAL_EXPORTS "${FN_ARG_CMAKE_ADDITIONAL_EXPORTS}")
   set(HERMETIC_FETCHCONTENT_TARGETS_FILE_PATTERN "${FN_ARG_TARGETS_FILE_PATTERN}")
 
+  # forward the ENABLED_LANGUAGES information to the dump project
+  # so that libraries forced to be found on system can take that
+  # info into account
+  set(TEMPLATE_ENABLE_LANGUAGES "NONE")
+  if(FORCE_SYSTEM_${content_name})
+    get_property(languages GLOBAL PROPERTY ENABLED_LANGUAGES)
+    set(TEMPLATE_ENABLE_LANGUAGES ${languages})
+  endif()
+
   string(RANDOM LENGTH 10 rand_str)
   set(tmp_proj_dir "${FN_ARG_TEMP_DIR}/tmp_${rand_str}")
 

cmake/modules/hfc_make_available_single.cmake

@@ -201,6 +201,7 @@ function(hfc_make_available_single content_name build_at_configure_time)
         ${content_name}
         LOAD_TARGETS_CMAKE "[==[find_package(${content_name} REQUIRED ${__PARAMS_FIND_PACKAGE_ARGS} ) \n]==]"
         CACHE_DESTINATION_FILE "${target_cache_file}"
+        CREATE_TARGET_ALIASES "${__PARAMS_HERMETIC_CREATE_TARGET_ALIASES}"
         TEMP_DIR "${HERMETIC_FETCHCONTENT_INSTALL_DIR}/targets_dump_tmp"
         TOOLCHAIN_FILE ${proxy_toolchain_path}
       )

cmake/templates/create_imported_cmake_targets_cache.CMakeLists.txt.in

@@ -14,7 +14,7 @@ function(create_target_aliases target_name OUT_aliases_name)
 
   block(PROPAGATE TARGET_NAME TARGET_ALIASES)
   # injected code
-  @TEMPLATE_CREATE_TARGET_ALIASES@
+  @CREATE_TARGET_ALIASES@
 
   endblock()
 

cmake/templates/dump_build_targets.CMakeLists.txt.in

@@ -13,7 +13,7 @@
 
 
 cmake_minimum_required(VERSION 3.27.0)
-project(dump_build_targets LANGUAGES NONE)
+project(dump_build_targets LANGUAGES @TEMPLATE_ENABLE_LANGUAGES@)
 
 
 list(APPEND CMAKE_MODULE_PATH "@HERMETIC_FETCHCONTENT_ROOT_DIR@")

test/targets_cache_test.cpp

@@ -56,7 +56,13 @@ namespace hfc::test {
     targets_cache_test_data_set{ "hfc_targets_cache/autotools_export_declaration", "Iconv.cmake", true },
     targets_cache_test_data_set{ "hfc_targets_cache/cmake_no_install", "mathslib.cmake", false },
     targets_cache_test_data_set{ "hfc_targets_cache/alternate_exports_naming", "mathslib.cmake", true },
-    targets_cache_test_data_set{ "hfc_targets_cache/alternate_exports_naming", "mathslib.cmake", false, false /* expect configure failure */, false, "-DHFCTEST_NEGATIVE_CASE=ON" /* enable the negative test in the project */ }
+    targets_cache_test_data_set{ "hfc_targets_cache/alternate_exports_naming", "mathslib.cmake", false, false /* expect configure failure */, false, "-DHFCTEST_NEGATIVE_CASE=ON" /* enable the negative test in the project */ },
+
+    // aliasing tests
+    targets_cache_test_data_set{ "hfc_targets_cache/target_aliasing", "mathslib.cmake", true, true , true /* expect build and  configure success */, "-D=HFC_TEST_RENAMETARGET=OFF" }, 
+    targets_cache_test_data_set{ "hfc_targets_cache/target_aliasing", "mathslib.cmake", true, true , true /* expect build and  configure success */, "-D=HFC_TEST_RENAMETARGET=ON" }, // rename instead of just adding an alias
+    targets_cache_test_data_set{ "hfc_targets_cache/target_aliasing", "mathslib.cmake", true, true , true /* expect build and  configure success */, "-D=HFC_TEST_FORCE_SYSTEM_RENAME_TARGET=OFF" }, 
+    targets_cache_test_data_set{ "hfc_targets_cache/target_aliasing", "mathslib.cmake", true, true , true /* expect build and  configure success */, "-D=HFC_TEST_FORCE_SYSTEM_RENAME_TARGET=ON" }, // rename instead of just adding an alias
   };
 
   static auto TEST_DATA_hfc_makeAvailableAt_type = {

test/test_project_templates/hfc_targets_cache/target_aliasing/CMakeLists.txt

@@ -0,0 +1,147 @@
+#
+# Base hfc targets cache functionality test 
+# ensures that packages and properties can be read from package config exports 
+#
+
+cmake_minimum_required(VERSION 3.27.6)
+project(
+  ModernCMakeExample
+  VERSION 1.0
+  LANGUAGES CXX)
+
+
+set(CMAKE_MODULE_PATH
+  "${CMAKE_CURRENT_SOURCE_DIR}/cmake"
+  "${CMAKE_CURRENT_SOURCE_DIR}/cmake/modules"
+  ${CMAKE_MODULE_PATH}
+)
+
+include(FetchContent)
+include(HermeticFetchContent)
+
+
+if(HFC_TEST_RENAMETARGET) 
+  set(mathlib_alias_fn
+    [==[
+    if("${TARGET_NAME}" STREQUAL "MathFunctionscbrt::MathFunctionscbrt")
+      set(TARGET_ALIASES "RenamedMathFunctionscbrt::MathFunctionscbrt") # rename
+    endif()
+    ]==]
+  )
+else()
+  set(mathlib_alias_fn
+    [==[
+    if("${TARGET_NAME}" STREQUAL "MathFunctionscbrt::MathFunctionscbrt")
+      list(APPEND TARGET_ALIASES "MathFunctionscbrt::MathFunctionscbrt" "AliasedMathFunctionscbrt::MathFunctionscbrt") # alias
+    endif()
+    ]==]
+  )
+endif()
+
+FetchContent_Declare(
+  mathslib
+  GIT_REPOSITORY "https://github.com/tipi-build/unit-test-cmake-template-2libs.git"
+  GIT_TAG "ecc756a4c3f1811cdfd637bd6d8f4e3feb6aff92"
+)
+
+FetchContent_MakeHermetic(mathslib  
+  HERMETIC_CREATE_TARGET_ALIASES "${mathlib_alias_fn}"
+)
+
+
+if(HFC_TEST_FORCE_SYSTEM_RENAME_TARGET)
+  set(iconv_alias_fn
+    [==[
+    if("${TARGET_NAME}" STREQUAL "Iconv::Iconv")
+      set(TARGET_ALIASES "RenamedIconv::Iconv") # rename
+    endif()
+    ]==]
+  )
+else()
+  set(iconv_alias_fn
+    [==[
+    if("${TARGET_NAME}" STREQUAL "Iconv::Iconv")
+      list(APPEND TARGET_ALIASES "Iconv::Iconv" "AliasedIconv::Iconv") # alias
+    endif()
+    ]==]
+  )
+endif()
+
+set(FORCE_SYSTEM_Iconv ON)
+
+FetchContent_Declare(
+  Iconv
+  GIT_REPOSITORY https://github.com/tipi-build/unittest-autotools-sample.git
+  GIT_TAG ad80b024eeda8f4c0a96eedf669dc453ed33a094 
+)
+
+FetchContent_MakeHermetic(
+  Iconv
+  HERMETIC_CMAKE_EXPORT_LIBRARY_DECLARATION 
+    [=[
+      message(FATAL_ERROR "This bit of code should not have been executed because we FORCE_SYSTEM_Iconv")
+    ]=]
+  HERMETIC_CREATE_TARGET_ALIASES "${iconv_alias_fn}"
+  HERMETIC_BUILD_SYSTEM autotools
+)
+
+if(HFCTEST_CONFIGURETIME_DEPENDENCY AND HFCTEST_BUILDTIME_DEPENDENCY)
+  set(param_error ON)
+else()
+  if(HFCTEST_CONFIGURETIME_DEPENDENCY) 
+    HermeticFetchContent_MakeAvailableAtConfigureTime(mathslib)
+    HermeticFetchContent_MakeAvailableAtConfigureTime(Iconv)
+  elseif(HFCTEST_BUILDTIME_DEPENDENCY)
+    HermeticFetchContent_MakeAvailableAtBuildTime(mathslib)
+    HermeticFetchContent_MakeAvailableAtBuildTime(Iconv)
+  else()
+    set(param_error ON)
+  endif()
+endif()
+
+if(param_error)
+  message(FATAL_ERROR "This project needs either HFCTEST_CONFIGURETIME_DEPENDENCY or HFCTEST_BUILDTIME_DEPENDENCY defined")
+endif()
+
+
+set(exampleTargetLinkLibs "MathFunctions::MathFunctions") # this one should always exist as we don't alias/rename it (we do that only for MathFunctionscbrt::MathFunctionscbrt)
+
+
+# check for expected targets of our mathlib content
+if(HFC_TEST_RENAMETARGET)
+  list(APPEND exampleTargetLinkLibs "RenamedMathFunctionscbrt::MathFunctionscbrt")
+
+  if(TARGET MathFunctionscbrt::MathFunctionscbrt)
+    message(FATAL_ERROR "Found target MathFunctionscbrt::MathFunctionscbrt which should not exist")
+  endif()
+else()
+  list(APPEND exampleTargetLinkLibs "AliasedMathFunctionscbrt::MathFunctionscbrt")
+
+  if(NOT TARGET MathFunctionscbrt::MathFunctionscbrt)
+    message(FATAL_ERROR "Didn't find target MathFunctionscbrt::MathFunctionscbrt which should still exist despite aliasing")
+  endif()
+endif()
+
+# check for expected targets of our Iconv content
+if(HFC_TEST_FORCE_SYSTEM_RENAME_TARGET)
+  list(APPEND exampleTargetLinkLibs "RenamedIconv::Iconv")
+
+  if(TARGET Iconv::Iconv)
+    message(FATAL_ERROR "Found target Iconv::Iconv which should not exist")
+  endif()
+
+else()
+
+  list(APPEND exampleTargetLinkLibs "AliasedIconv::Iconv")
+
+  if(NOT TARGET Iconv::Iconv)
+    message(FATAL_ERROR "Didn't find target Iconv::Iconv which should still exist despite aliasing")
+  endif()
+
+endif()
+
+
+add_executable(MyExample simple_example.cpp)
+target_link_libraries(MyExample PRIVATE ${exampleTargetLinkLibs})
+
+

test/test_project_templates/hfc_targets_cache/target_aliasing/simple_example.cpp

@@ -0,0 +1,5 @@
+#include <MathFunctions.h>
+
+int main() {
+    return MathFunctions::sqrt(4.0) == 2.0;
+}