$NetBSD: patch-tree_CMakeLists.txt,v 1.1 2024/08/05 20:38:39 adam Exp $

Use system pybind11 and absl.
https://github.com/google-deepmind/tree/pull/73

--- tree/CMakeLists.txt.orig	2024-08-05 19:44:05.774867683 +0000
+++ tree/CMakeLists.txt
@@ -51,68 +51,12 @@ if(APPLE)
 endif()
 
 # Fetch pybind to be able to use pybind11_add_module symbol.
-set(PYBIND_VER v2.10.1)
-include(FetchContent)
-FetchContent_Declare(
-  pybind11
-  GIT_REPOSITORY https://github.com/pybind/pybind11
-  GIT_TAG        ${PYBIND_VER}
-)
-if(NOT pybind11_POPULATED)
-    FetchContent_Populate(pybind11)
-    add_subdirectory(${pybind11_SOURCE_DIR} ${pybind11_BINARY_DIR})
-    include_directories(${pybind11_INCLUDE_DIR})
-endif()
-
-# Needed to disable Abseil tests.
-set (BUILD_TESTING OFF)
-
-# Include abseil-cpp.
-set(ABSEIL_VER 20210324.2)
-include(ExternalProject)
-set(ABSEIL_CMAKE_ARGS
-    "-DCMAKE_INSTALL_PREFIX=${CMAKE_SOURCE_DIR}/abseil-cpp"
-    "-DCMAKE_CXX_STANDARD=${CMAKE_CXX_STANDARD}"
-    "-DCMAKE_CXX_COMPILER=${CMAKE_CXX_COMPILER}"
-    "-DCMAKE_CXX_FLAGS=${CMAKE_CXX_FLAGS}"
-    "-DCMAKE_BUILD_TYPE=${CMAKE_BUILD_TYPE}"
-    "-DCMAKE_POSITION_INDEPENDENT_CODE=${CMAKE_POSITION_INDEPENDENT_CODE}"
-    "-DLIBRARY_OUTPUT_PATH=${CMAKE_SOURCE_DIR}/abseil-cpp/lib")
-if(DEFINED CMAKE_OSX_ARCHITECTURES)
-    set(ABSEIL_CMAKE_ARGS
-        ${ABSEIL_CMAKE_ARGS}
-        "-DCMAKE_OSX_ARCHITECTURES=${CMAKE_OSX_ARCHITECTURES}")
-endif()
-ExternalProject_Add(abseil-cpp
-  GIT_REPOSITORY    https://github.com/abseil/abseil-cpp.git
-  GIT_TAG           ${ABSEIL_VER}
-  PREFIX            ${CMAKE_SOURCE_DIR}/abseil-cpp
-  CMAKE_ARGS        ${ABSEIL_CMAKE_ARGS}
-)
-ExternalProject_Get_Property(abseil-cpp install_dir)
-set(abseil_install_dir ${install_dir})
-include_directories (${abseil_install_dir}/include)
-
+find_package(pybind11 REQUIRED CONFIG)
+find_package(absl REQUIRED)
 
 # Define pybind11 tree module.
 pybind11_add_module(_tree tree.h tree.cc)
-add_dependencies(_tree abseil-cpp)
-
-if (WIN32 OR MSVC)
-    set(ABSEIL_LIB_PREF "absl")
-    set(LIB_SUFF "lib")
-else()
-    set(ABSEIL_LIB_PREF "libabsl")
-    set(LIB_SUFF "a")
-endif()
-
-# Link abseil static libs.
-# We don't use find_library here to force cmake to build abseil before linking.
-set(ABSEIL_LIBS int128 raw_hash_set raw_logging_internal strings throw_delegate)
-foreach(ABSEIL_LIB IN LISTS ABSEIL_LIBS)
-  target_link_libraries(_tree PRIVATE
-      "${abseil_install_dir}/lib/${ABSEIL_LIB_PREF}_${ABSEIL_LIB}.${LIB_SUFF}")
-endforeach()
+target_link_libraries(_tree PRIVATE absl::int128 absl::raw_hash_set absl::raw_logging_internal absl::strings absl::throw_delegate)
 
 # Make the module private to tree package.
 set_target_properties(_tree PROPERTIES OUTPUT_NAME tree/_tree)