Add CMake support for chpl-shim

Signed-off-by: Danila Fedorin <daniel.fedorin@hpe.com>

Author: DanilaFe

util/cmake/CMakeCHPLInformation.cmake

@@ -19,7 +19,25 @@
 # TODO: this is a hack, how do we tell cmake that we can't compile to object files?
 # TODO: how do we respect <DEFINES> and <INCLUDES>, CMake will only fill that in for CMAKE_*_COMPILER_OBJECT
 set(CMAKE_CHPL_COMPILE_OBJECT "test -f <OBJECT> || ln -s <SOURCE> <OBJECT>")
+
+# Support for CMAKE_EXPORT_CHPL_COMMANDS (similar to CMAKE_EXPORT_COMPILE_COMMANDS)
 set(CMAKE_CHPL_LINK_EXECUTABLE "<CMAKE_CHPL_COMPILER> -o <TARGET> <OBJECTS> <FLAGS> <LINK_FLAGS> <LINK_LIBRARIES>")
+if(CMAKE_EXPORT_CHPL_COMMANDS)
+  # Get the directory containing the chpl compiler to find chpl-shim
+  get_filename_component(CHPL_BIN_DIR "${CMAKE_CHPL_COMPILER}" DIRECTORY)
+  set(CHPL_SHIM_SCRIPT "${CHPL_BIN_DIR}/chpl-shim")
+
+  message(STATUS "CMAKE_EXPORT_CHPL_COMMANDS is ON, checking for chpl-shim at ${CHPL_SHIM_SCRIPT}")
+
+  if(EXISTS "${CHPL_SHIM_SCRIPT}")
+    # Use chpl-shim as a wrapper to generate .cls-commands.json
+    # Note: chpl-shim expects to be called as 'chpl-shim chpl <args>', not with full path
+    message(STATUS "Using chpl-shim to generate .cls-commands.json")
+    set(CMAKE_CHPL_LINK_EXECUTABLE "<CMAKE_COMMAND> -E env CHPL_SHIM_REAL_COMPILER_PATH=${CMAKE_CHPL_COMPILER} ${CHPL_SHIM_SCRIPT} chpl -o <TARGET> <OBJECTS> <FLAGS> <LINK_FLAGS> <LINK_LIBRARIES>")
+  else()
+    message(WARNING "CMAKE_EXPORT_CHPL_COMMANDS is set but chpl-shim not found at ${CHPL_SHIM_SCRIPT}")
+  endif()
+endif()
 
 # TODO: support --library directly to build Chapel shared libs for interoperability
 # CMAKE_*_CREATE_SHARED_LIBRARY