File 0001-Optionally-use-system-provided-Catch2.patch of Package netgen

From 2aa63672c1ec26a96a4d0ce111370e333fb78e6f Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Stefan=20Br=C3=BCns?= <stefan.bruens@rwth-aachen.de>
Date: Wed, 3 Mar 2021 18:45:22 +0100
Subject: [PATCH] Optionally use system provided Catch2

---
 CMakeLists.txt         | 12 +++++++++++-
 cmake/SuperBuild.cmake |  1 +
 2 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 8e5ade9b..036ccc01 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -31,6 +31,8 @@ option( DEBUG_LOG "Enable more debug output (may increase computation time) - on
 option( CHECK_RANGE "Check array range access, automatically enabled if built in debug mode" OFF)
 option( BUILD_STUB_FILES "Build stub files for better autocompletion" ON)
 option( BUILD_FOR_CONDA "Link python libraries only to executables" OFF)
+option( DOWNLOAD_DEPENDENCIES "Download any dependencies not found on the system" ON)
+
 
 option( USE_SUPERBUILD       "use ccache" ON)
 option( TRACE_MEMORY     "Enable memory tracing" OFF)
@@ -378,7 +380,16 @@ enable_testing()
 include(CTest)
 
 if(ENABLE_UNIT_TESTS)
-  include(${CMAKE_CURRENT_LIST_DIR}/cmake/external_projects/catch.cmake)
+  if(DOWNLOAD_DEPENDENCIES)
+    include(${CMAKE_CURRENT_LIST_DIR}/cmake/external_projects/catch.cmake)
+  else(DOWNLOAD_DEPENDENCIES)
+    find_package(Catch2 REQUIRED)
+    set_target_properties(Catch2::Catch2 PROPERTIES IMPORTED_GLOBAL TRUE)
+    add_library(project_catch ALIAS Catch2::Catch2)
+    get_target_property(_CATCH_INCLUDE_DIR_BASE Catch2::Catch2 INTERFACE_INCLUDE_DIRECTORIES)
+    string(CONCAT CATCH_INCLUDE_DIR ${_CATCH_INCLUDE_DIR_BASE} "/catch2")
+  endif(DOWNLOAD_DEPENDENCIES)
+  message(STATUS "Catch2 include dir: ${CATCH_INCLUDE_DIR}")
 endif(ENABLE_UNIT_TESTS)
 
 
diff --git a/cmake/SuperBuild.cmake b/cmake/SuperBuild.cmake
index 6e9600df..da6e3a96 100644
--- a/cmake/SuperBuild.cmake
+++ b/cmake/SuperBuild.cmake
@@ -139,6 +139,7 @@ set_vars( NETGEN_CMAKE_ARGS
   CMAKE_PREFIX_PATH
   CMAKE_INSTALL_PREFIX
   ENABLE_UNIT_TESTS
+  DOWNLOAD_DEPENDENCIES
   ENABLE_CPP_CORE_GUIDELINES_CHECK
   USE_SPDLOG
   DEBUG_LOG
-- 
2.30.1