From 58db77cd0ac101195af747411450e13aef568cd3 Mon Sep 17 00:00:00 2001
From: Gavin Ridley <gavin.keith.ridley@gmail.com>
Date: Wed, 10 Feb 2021 12:33:42 -0500
Subject: [PATCH] revert to original recursive submodule approach

---
 CMakeLists.txt | 37 ++++++++++++-------------------------
 1 file changed, 12 insertions(+), 25 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index f21ddf6485..692f97b9c5 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -144,40 +144,27 @@ endif()
 # Update git submodules as needed
 #===============================================================================
 
-# Function that updates a git submodule, and double-checks that it exists
-function(update_git_submodule git_submodule_name)
-  execute_process(COMMAND ${GIT_EXECUTABLE} submodule update --init vendor/${git_submodule_name}
-                  WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}
-                  RESULT_VARIABLE GIT_SUBMOD_RESULT)
-  if(NOT GIT_SUBMOD_RESULT EQUAL 0)
-    message(FATAL_ERROR "git submodule update --init failed with \
-      ${GIT_SUBMOD_RESULT} on ${git_submodule_name}, please checkout submodules")
-  endif()
-
-  # Double-check submodule indeed exists
-  if(NOT EXISTS "${CMAKE_CURRENT_SOURCE_DIR}/vendor/${git_submodule_name}/CMakeLists.txt")
-    message(FATAL_ERROR "The git submodule ${git_submodule_name} was not downloaded! GIT_SUBMODULE was \
-      turned off or failed. Please update the ${git_submodule_name} submodule and try again.")
-  endif()
-endfunction()
-
 find_package(Git)
 if(GIT_FOUND AND EXISTS "${CMAKE_CURRENT_SOURCE_DIR}/.git")
   option(GIT_SUBMODULE "Check submodules during build" ON)
   if(GIT_SUBMODULE)
     message(STATUS "Submodule update")
-    if (NOT fmt_FOUND)
-      update_git_submodule(fmt)
+    execute_process(COMMAND ${GIT_EXECUTABLE} submodule update --init --recursive
+                    WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}
+                    RESULT_VARIABLE GIT_SUBMOD_RESULT)
+    if(NOT GIT_SUBMOD_RESULT EQUAL 0)
+      message(FATAL_ERROR "git submodule update --init failed with \
+        ${GIT_SUBMOD_RESULT}, please checkout submodules")
     endif()
-    if (NOT pugixml_FOUND)
-      update_git_submodule(pugixml)
-    endif()
-    update_git_submodule(gsl-lite)
-    update_git_submodule(xtensor)
-    update_git_submodule(xtl)
   endif()
 endif()
 
+# Check to see if submodules exist (by checking one)
+if(NOT EXISTS "${CMAKE_CURRENT_SOURCE_DIR}/vendor/pugixml/CMakeLists.txt")
+  message(FATAL_ERROR "The git submodules were not downloaded! GIT_SUBMODULE was \
+    turned off or failed. Please update submodules and try again.")
+endif()
+
 #===============================================================================
 # pugixml library
 #===============================================================================