Modernize CMake support

Author: d-frey

CMakeLists.txt

@@ -1,42 +1,66 @@
-cmake_minimum_required (VERSION 3.2.0 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.2.0 FATAL_ERROR)
 
-project (taocpp-operators VERSION 1.1.1 LANGUAGES CXX)
+project(taocpp-operators VERSION 1.2.0 LANGUAGES CXX)
+
+if(${PROJECT_NAME}_FOUND)
+  # multiple versions can't co-exist
+  if(NOT ${PROJECT_NAME}_VERSION STREQUAL ${PROJECT_VERSION})
+    message(FATAL_ERROR "Multiple mismatched versions")
+  endif()
+
+  # only include if this is the first include
+  if(NOT ${PROJECT_NAME}_DIR STREQUAL "${PROJECT_BINARY_DIR}")
+    return()
+  endif()
+endif()
+
+# keep track of version
+set(${PROJECT_NAME}_FOUND TRUE CACHE BOOL "" FORCE)
+set(${PROJECT_NAME}_VERSION "${PROJECT_VERSION}" CACHE STRING "" FORCE)
+set(${PROJECT_NAME}_DIR "${PROJECT_BINARY_DIR}" CACHE PATH "" FORCE)
+
+mark_as_advanced(${PROJECT_NAME}_FOUND)
+mark_as_advanced(${PROJECT_NAME}_VERSION)
+mark_as_advanced(${PROJECT_NAME}_DIR)
 
 # installation directories
-set (TAOCPP_OPERATORS_INSTALL_INCLUDE_DIR "include" CACHE STRING "The installation include directory")
-set (TAOCPP_OPERATORS_INSTALL_DOC_DIR "share/doc/tao/operators" CACHE STRING "The installation doc directory")
-set (TAOCPP_OPERATORS_INSTALL_CMAKE_DIR "share/taocpp-operators/cmake" CACHE STRING "The installation cmake directory")
+set(TAOCPP_OPERATORS_INSTALL_INCLUDE_DIR "include" CACHE STRING "The installation include directory")
+set(TAOCPP_OPERATORS_INSTALL_DOC_DIR "share/doc/tao/operators" CACHE STRING "The installation doc directory")
+set(TAOCPP_OPERATORS_INSTALL_CMAKE_DIR "share/taocpp-operators/cmake" CACHE STRING "The installation cmake directory")
 
 # define a header-only library
-add_library (operators INTERFACE)
-add_library (taocpp::operators ALIAS operators)
-target_include_directories (operators INTERFACE
+add_library(taocpp-operators INTERFACE)
+add_library(taocpp::operators ALIAS taocpp-operators)
+target_include_directories(taocpp-operators INTERFACE
   $<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}/include>
   $<INSTALL_INTERFACE:${TAOCPP_OPERATORS_INSTALL_INCLUDE_DIR}>
 )
 
 # features used by taocpp/operators
-target_compile_features (operators INTERFACE
+target_compile_features(taocpp-operators INTERFACE
   cxx_constexpr
   cxx_noexcept
   cxx_rvalue_references
 )
 
 # testing
-enable_testing ()
-option (TAOCPP_OPERATORS_BUILD_TESTS "Build test programs" ON)
-if (TAOCPP_OPERATORS_BUILD_TESTS)
-  add_subdirectory (src/test/operators)
-endif ()
+enable_testing()
+option(TAOCPP_OPERATORS_BUILD_TESTS "Build test programs" ON)
+if(TAOCPP_OPERATORS_BUILD_TESTS)
+  add_subdirectory(src/test/operators)
+endif()
+
+# make package findable
+configure_file(cmake/dummy-config.cmake.in taocpp-operators-config.cmake @ONLY)
 
 # install and export target
-install (TARGETS operators EXPORT operators-targets)
+install(TARGETS taocpp-operators EXPORT taocpp-operators-targets)
 
-install (EXPORT operators-targets
+install(EXPORT taocpp-operators-targets
   FILE taocpp-operators-config.cmake
   NAMESPACE taocpp::
   DESTINATION ${TAOCPP_OPERATORS_INSTALL_CMAKE_DIR}
 )
 
-install (DIRECTORY include/ DESTINATION ${TAOCPP_OPERATORS_INSTALL_INCLUDE_DIR})
-install (FILES LICENSE DESTINATION ${TAOCPP_OPERATORS_INSTALL_DOC_DIR})
+install(DIRECTORY include/ DESTINATION ${TAOCPP_OPERATORS_INSTALL_INCLUDE_DIR})
+install(FILES LICENSE DESTINATION ${TAOCPP_OPERATORS_INSTALL_DOC_DIR})

cmake/dummy-config.cmake.in

@@ -0,0 +1,5 @@
+# Dummy config file
+# When a dependency is added with add_subdirectory, but searched with find_package
+
+# Redirect to the directory added with add_subdirectory
+add_subdirectory(@PROJECT_SOURCE_DIR@ @PROJECT_BINARY_DIR@)

src/test/operators/CMakeLists.txt

@@ -1,39 +1,39 @@
-cmake_minimum_required (VERSION 3.3.0 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.3.0 FATAL_ERROR)
 
-set (test_sources
+set(test_sources
   no_rvalue_reference_results.cpp
   test_operators.cpp
 )
 
-# file (GLOB ...) is used to validate the above list of test_sources
-file (GLOB glob_test_sources RELATIVE ${CMAKE_CURRENT_LIST_DIR} *.cpp)
+# file(GLOB ...) is used to validate the above list of test_sources
+file(GLOB glob_test_sources RELATIVE ${CMAKE_CURRENT_LIST_DIR} *.cpp)
 
-foreach (testsourcefile ${test_sources})
-  if (${testsourcefile} IN_LIST glob_test_sources)
-    list (REMOVE_ITEM glob_test_sources ${testsourcefile})
-  else ()
-    message (SEND_ERROR "File ${testsourcefile} is missing from src/test/operators")
-  endif ()
+foreach(testsourcefile ${test_sources})
+  if(${testsourcefile} IN_LIST glob_test_sources)
+    list(REMOVE_ITEM glob_test_sources ${testsourcefile})
+  else()
+    message(SEND_ERROR "File ${testsourcefile} is missing from src/test/operators")
+  endif()
 
-  get_filename_component (exename ${testsourcefile} NAME_WE)
-  set (exename "tao-operators-test-${exename}")
-  add_executable (${exename} ${testsourcefile})
-  target_link_libraries (${exename} PRIVATE taocpp::operators)
-  set_target_properties (${exename} PROPERTIES
+  get_filename_component(exename ${testsourcefile} NAME_WE)
+  set(exename "tao-operators-test-${exename}")
+  add_executable(${exename} ${testsourcefile})
+  target_link_libraries(${exename} PRIVATE taocpp::operators)
+  set_target_properties(${exename} PROPERTIES
     CXX_STANDARD 11
     CXX_STANDARD_REQUIRED ON
     CXX_EXTENSIONS OFF
   )
-  if (MSVC)
-    target_compile_options (${exename} PRIVATE /W4 /WX /utf-8)
-  else ()
-    target_compile_options (${exename} PRIVATE -pedantic -Wall -Wextra -Wshadow -Werror)
-  endif ()
-  add_test (NAME ${exename} WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}/../../.. COMMAND ${CMAKE_CURRENT_BINARY_DIR}/${exename})
-endforeach (testsourcefile)
+  if(MSVC)
+    target_compile_options(${exename} PRIVATE /W4 /WX /utf-8)
+  else()
+    target_compile_options(${exename} PRIVATE -pedantic -Wall -Wextra -Wshadow -Werror)
+  endif()
+  add_test(NAME ${exename} WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}/../../.. COMMAND ${exename})
+endforeach(testsourcefile)
 
-if (glob_test_sources)
-  foreach (ignored_source_file ${glob_test_sources})
-    message (SEND_ERROR "File ${ignored_source_file} in src/test/operators is ignored")
-  endforeach (ignored_source_file)
-endif ()
+if(glob_test_sources)
+  foreach(ignored_source_file ${glob_test_sources})
+    message(SEND_ERROR "File ${ignored_source_file} in src/test/operators is ignored")
+  endforeach(ignored_source_file)
+endif()