[R] Remove dependency on gendef for Visual Studio builds (fixes #5608) (#5764)

* [R-package] Remove dependency on gendef for Visual Studio builds (fixes #5608)

* clarify docs

* removed debugging print statement

* Make R CMake install more robust

* Fix doc format; add ToC

* Update build.rst

* Fix AppVeyor

Co-authored-by: Hyunsu Cho <chohyu01@cs.washington.edu>

cmake/RPackageInstall.cmake.in

@@ -0,0 +1,34 @@
+# Commands to install the R package as a CMake install target
+
+function(check_call)
+  set(cmd COMMAND)
+  cmake_parse_arguments(
+    PARSE_ARGV 0
+    CALL_ARG "" "" "${cmd}"
+  )
+  string(REPLACE ";" " " commands "${CALL_ARG_COMMAND}")
+  message("Command: ${commands}")
+  execute_process(COMMAND ${CALL_ARG_COMMAND}
+                  OUTPUT_VARIABLE _out
+				  ERROR_VARIABLE _err
+				  RESULT_VARIABLE _res)
+  if(NOT "${_res}" EQUAL "0")
+    message(FATAL_ERROR "out: ${_out}, err: ${_err}, res: ${_res}")
+  endif()
+endfunction()
+
+# Important paths
+set(build_dir "@build_dir@")
+set(LIBR_EXECUTABLE "@LIBR_EXECUTABLE@")
+
+# Back up cmake_install.cmake
+file(WRITE "${build_dir}/R-package/src/Makevars" "all:")
+file(WRITE "${build_dir}/R-package/src/Makevars.win" "all:")
+
+# Install dependencies
+set(XGB_DEPS_SCRIPT
+    "deps = setdiff(c('data.table', 'magrittr', 'stringi'), rownames(installed.packages())); if(length(deps)>0) install.packages(deps, repo = 'https://cloud.r-project.org/')")
+check_call(COMMAND "${LIBR_EXECUTABLE}" -q -e "${XGB_DEPS_SCRIPT}")
+
+# Install the XGBoost R package
+check_call(COMMAND "${LIBR_EXECUTABLE}" CMD INSTALL --no-multiarch --build "${build_dir}/R-package")

cmake/RPackageInstallTargetSetup.cmake

@@ -0,0 +1,16 @@
+# Assembles the R-package files in build_dir;
+# if necessary, installs the main R package dependencies;
+# runs R CMD INSTALL.
+function(setup_rpackage_install_target rlib_target build_dir)
+  configure_file(${PROJECT_SOURCE_DIR}/cmake/RPackageInstall.cmake.in ${PROJECT_BINARY_DIR}/RPackageInstall.cmake @ONLY)
+  install(
+    DIRECTORY "${xgboost_SOURCE_DIR}/R-package"
+    DESTINATION "${build_dir}"
+    REGEX "src/*" EXCLUDE
+    REGEX "R-package/configure" EXCLUDE
+  )
+  install(TARGETS ${rlib_target}
+    LIBRARY DESTINATION "${build_dir}/R-package/src/"
+    RUNTIME DESTINATION "${build_dir}/R-package/src/")
+  install(SCRIPT ${PROJECT_BINARY_DIR}/RPackageInstall.cmake)
+endfunction()

cmake/Utils.cmake

@@ -110,38 +110,6 @@ function(format_gencode_flags flags out)
   set(${out} "${${out}}" PARENT_SCOPE)
 endfunction(format_gencode_flags flags)
 
-# Assembles the R-package files in build_dir;
-# if necessary, installs the main R package dependencies;
-# runs R CMD INSTALL.
-function(setup_rpackage_install_target rlib_target build_dir)
-  # backup cmake_install.cmake
-  install(CODE "file(COPY \"${build_dir}/R-package/cmake_install.cmake\"
-DESTINATION \"${build_dir}/bak\")")
-
-  install(CODE "file(REMOVE_RECURSE \"${build_dir}/R-package\")")
-  install(
-    DIRECTORY "${xgboost_SOURCE_DIR}/R-package"
-    DESTINATION "${build_dir}"
-    REGEX "src/*" EXCLUDE
-    REGEX "R-package/configure" EXCLUDE
-  )
-  install(TARGETS ${rlib_target}
-    LIBRARY DESTINATION "${build_dir}/R-package/src/"
-    RUNTIME DESTINATION "${build_dir}/R-package/src/")
-  install(CODE "file(WRITE \"${build_dir}/R-package/src/Makevars\" \"all:\")")
-  install(CODE "file(WRITE \"${build_dir}/R-package/src/Makevars.win\" \"all:\")")
-  set(XGB_DEPS_SCRIPT
-    "deps = setdiff(c('data.table', 'magrittr', 'stringi'), rownames(installed.packages()));\
-    if(length(deps)>0) install.packages(deps, repo = 'https://cloud.r-project.org/')")
-  install(CODE "execute_process(COMMAND \"${LIBR_EXECUTABLE}\" \"-q\" \"-e\" \"${XGB_DEPS_SCRIPT}\")")
-  install(CODE "execute_process(COMMAND \"${LIBR_EXECUTABLE}\" CMD INSTALL\
-    \"--no-multiarch\" \"--build\" \"${build_dir}/R-package\")")
-
-  # restore cmake_install.cmake
-  install(CODE "file(RENAME \"${build_dir}/bak/cmake_install.cmake\"
- \"${build_dir}/R-package/cmake_install.cmake\")")
-endfunction(setup_rpackage_install_target)
-
 macro(enable_nvtx target)
   find_package(NVTX REQUIRED)
   target_include_directories(${target} PRIVATE "${NVTX_INCLUDE_DIR}")

cmake/modules/FindLibR.cmake

@@ -23,7 +23,7 @@
 
 # Windows users might want to change this to their R version:
 if(NOT R_VERSION)
-  set(R_VERSION "3.4.1")
+  set(R_VERSION "4.0.0")
 endif()
 if(NOT R_ARCH)
   if("${CMAKE_SIZEOF_VOID_P}" STREQUAL "4")
@@ -43,16 +43,26 @@ function(create_rlib_for_msvc)
   if(NOT EXISTS "${LIBR_LIB_DIR}")
     message(FATAL_ERROR "LIBR_LIB_DIR was not set!")
   endif()
-  find_program(GENDEF_EXE gendef)
   find_program(DLLTOOL_EXE dlltool)
-  if(NOT GENDEF_EXE OR NOT DLLTOOL_EXE)
-    message(FATAL_ERROR "\nEither gendef.exe or dlltool.exe not found!\
+  if(NOT DLLTOOL_EXE)
+    message(FATAL_ERROR "\ndlltool.exe not found!\
       \nDo you have Rtools installed with its MinGW's bin/ in PATH?")
-  endif()  
+  endif()
+
   # extract symbols from R.dll into R.def and R.lib import library
-  execute_process(COMMAND ${GENDEF_EXE}
-    "-" "${LIBR_LIB_DIR}/R.dll"
-    OUTPUT_FILE "${CMAKE_CURRENT_BINARY_DIR}/R.def")
+  get_filename_component(
+    LIBR_RSCRIPT_EXECUTABLE_DIR
+    ${LIBR_EXECUTABLE}
+    DIRECTORY
+  )
+  set(LIBR_RSCRIPT_EXECUTABLE "${LIBR_RSCRIPT_EXECUTABLE_DIR}/Rscript")
+
+  execute_process(
+    COMMAND ${LIBR_RSCRIPT_EXECUTABLE}
+    "${CMAKE_CURRENT_BINARY_DIR}/../../R-package/inst/make-r-def.R"
+    "${LIBR_LIB_DIR}/R.dll" "${CMAKE_CURRENT_BINARY_DIR}/R.def"
+  )
+
   execute_process(COMMAND ${DLLTOOL_EXE}
     "--input-def" "${CMAKE_CURRENT_BINARY_DIR}/R.def"
     "--output-lib" "${CMAKE_CURRENT_BINARY_DIR}/R.lib")