From 112e626760265233919cd3457ba82b1602d434b5 Mon Sep 17 00:00:00 2001
From: Emily Boudreaux <emily@boudreauxmail.com>
Date: Wed, 12 Feb 2025 16:24:13 -0500
Subject: [PATCH] feat(mfem): added mfem into source tree along with patch
 based build system

MFEM is a dependency of our code and we want to build it with our code for portability, here I add a meson subproject which fetches mfem and builds it. Because of some issues with CMake and meson I apply a patch which manually disables running tests and building examples and miniapps in mfem. This is okay as mfem here is not intenteded to be linked against other programs (though it still can be).
---
 build-config/meson.build                      |  1 +
 .../mfem/disable_mfem_selfcheck.patch         | 41 +++++++++++++++++++
 build-config/mfem/meson.build                 | 24 +++++++++++
 meson.build                                   |  3 ++
 subprojects/mfem.wrap                         |  5 +++
 5 files changed, 74 insertions(+)
 create mode 100644 build-config/meson.build
 create mode 100644 build-config/mfem/disable_mfem_selfcheck.patch
 create mode 100644 build-config/mfem/meson.build
 create mode 100644 subprojects/mfem.wrap

diff --git a/build-config/meson.build b/build-config/meson.build
new file mode 100644
index 0000000..cefc100
--- /dev/null
+++ b/build-config/meson.build
@@ -0,0 +1 @@
+subdir('mfem')
\ No newline at end of file
diff --git a/build-config/mfem/disable_mfem_selfcheck.patch b/build-config/mfem/disable_mfem_selfcheck.patch
new file mode 100644
index 0000000..8e438c0
--- /dev/null
+++ b/build-config/mfem/disable_mfem_selfcheck.patch
@@ -0,0 +1,41 @@
+--- subprojects/mfem/CMakeLists.txt	2025-02-12 15:54:52.454728232 -0500
++++ CMakeLists.txt.bak	2025-02-12 16:08:06.654542689 -0500
+@@ -765,7 +765,7 @@
+ if (MFEM_ENABLE_EXAMPLES)
+   add_subdirectory(examples) #install examples if enabled
+ else()
+-  add_subdirectory(examples EXCLUDE_FROM_ALL)
++  # add_subdirectory(examples EXCLUDE_FROM_ALL)
+ endif()
+ 
+ # Create a target for all miniapps and, optionally, enable it.
+@@ -774,7 +774,7 @@
+ if (MFEM_ENABLE_MINIAPPS)
+   add_subdirectory(miniapps) #install miniapps if enabled
+ else()
+-  add_subdirectory(miniapps EXCLUDE_FROM_ALL)
++  # add_subdirectory(miniapps EXCLUDE_FROM_ALL)
+ endif()
+ 
+ # Target to build all executables, i.e. everything.
+@@ -801,19 +801,7 @@
+   add_dependencies(${MFEM_EXEC_PREREQUISITES_TARGET_NAME} copy_data)
+ endif()
+ 
+-# Add 'check' target - quick test
+-set(MFEM_CHECK_TARGET_NAME ${MFEM_CUSTOM_TARGET_PREFIX}check)
+-if (NOT MFEM_USE_MPI)
+-  add_custom_target(${MFEM_CHECK_TARGET_NAME}
+-    ${CMAKE_CTEST_COMMAND} -R \"^ex1_ser\" -C ${CMAKE_CFG_INTDIR}
+-    USES_TERMINAL)
+-  add_dependencies(${MFEM_CHECK_TARGET_NAME} ex1)
+-else()
+-  add_custom_target(${MFEM_CHECK_TARGET_NAME}
+-    ${CMAKE_CTEST_COMMAND} -R \"^ex1p\" -C ${CMAKE_CFG_INTDIR}
+-    USES_TERMINAL)
+-  add_dependencies(${MFEM_CHECK_TARGET_NAME} ex1p)
+-endif()
++message(STATUS "MFEM Miniapps and Examples disabled by patch!")
+ 
+ #-------------------------------------------------------------------------------
+ # Documentation
diff --git a/build-config/mfem/meson.build b/build-config/mfem/meson.build
new file mode 100644
index 0000000..84f69c8
--- /dev/null
+++ b/build-config/mfem/meson.build
@@ -0,0 +1,24 @@
+cmake = import('cmake')
+patchFile = files('disable_mfem_selfcheck.patch')
+
+patch_check = run_command('grep', '-q', 'MFEM_CHECK_TARGET_NAME', 'subprojects/mfem/CMakeLists.txt', check: false)
+if patch_check.returncode() == 0
+    message('Patching MFEM CMakeLists.txt to remove self checks')
+    run_command('patch', '-p4', '-d', '../../subprojects/mfem', '-i', patchFile[0].full_path(), check: true)
+else
+    message('MFEM CMakeLists.txt already patched')
+endif
+
+mfem_cmake_options = cmake.subproject_options()
+mfem_cmake_options.add_cmake_defines({
+    'MFEM_ENABLE_EXAMPLES': 'OFF',
+    'MFEM_ENABLE_TESTING': 'OFF',
+    'MFEM_ENABLE_MINIAPPS': 'OFF',
+    'MFEM_USE_BENCMARK': 'OFF',
+})
+
+mfem_sp = cmake.subproject(
+    'mfem',
+    options: mfem_cmake_options)
+mfem_dep = mfem_sp.dependency('mfem')
+add_project_arguments('-I' + meson.current_build_dir() + '/subprojects/mfem/__CMake_build/config', language: 'cpp')
\ No newline at end of file
diff --git a/meson.build b/meson.build
index 43145c8..fa228b5 100644
--- a/meson.build
+++ b/meson.build
@@ -3,7 +3,10 @@ project('4DSSE', 'cpp', version: '0.0.1a', default_options: ['cpp_std=c++23'])
 # Add default visibility for all C++ targets
 add_project_arguments('-fvisibility=default', language: 'cpp')
 
+# Build external dependencies
+subdir('build-config')
 
+# Build the main project
 subdir('src')
 if get_option('build_tests')
     subdir('tests')
diff --git a/subprojects/mfem.wrap b/subprojects/mfem.wrap
new file mode 100644
index 0000000..43c167b
--- /dev/null
+++ b/subprojects/mfem.wrap
@@ -0,0 +1,5 @@
+[wrap-git]
+url = https://github.com/mfem/mfem.git
+revision = master
+
+[cmake]
\ No newline at end of file