Use superproject BOOST_INCLUDE_DIR if set

Extract unittest specific cmake into separate unit to clean up
the main CMakeLists.txt.

fixes codership/wsrep-lib#231

CMakeLists.txt

@@ -126,61 +126,7 @@ else()
   set(WSREP_LIB_LIBDL "")
 endif()
 
-set(MIN_BOOST_VERSION "1.54.0")
+include(cmake/unittests.cmake)
-if (WSREP_LIB_WITH_UNIT_TESTS)
-  if (WSREP_LIB_WITH_UNIT_TESTS_EXTRA)
-    message(STATUS "Compiling extra unit tests")
-    set(json_HEADER "boost/json/src.hpp")
-    # Extra tests may require packages from very recent boost which may be
-    # unavailable on the system. In such case download private boost distro.
-    check_include_file_cxx(${json_HEADER} system_json_FOUND)
-    if (NOT system_json_FOUND)
-      if (NOT WITH_BOOST)
-        set(WITH_BOOST "${CMAKE_SOURCE_DIR}/third_party/boost")
-      endif()
-      set(DOWNLOAD_BOOST ON)
-      include (cmake/boost.cmake)
-      set(MIN_BOOST_VERSION "${BOOST_MAJOR}.${BOOST_MINOR}.${BOOST_PATCH}")
-      message(STATUS "Boost includes: ${BOOST_INCLUDE_DIR}, ver: ${MIN_BOOST_VERSION}")
-      find_package(Boost ${MIN_BOOST_VERSION} REQUIRED
-        COMPONENTS json headers unit_test_framework
-        PATHS ${WITH_BOOST}/lib/cmake
-        NO_DEFAULT_PATH
-        )
-      # Include as system header to be more permissive about generated
-      # warnings.
-      set(CMAKE_REQUIRED_FLAGS "-isystem ${BOOST_INCLUDE_DIR}")
-      check_include_file_cxx(${json_HEADER} json_FOUND)
-      if (NOT json_FOUND)
-        message(FATAL_ERROR "Required header 'boost/json.hpp' not found: ${json_FOUND}")
-      else()
-        include_directories(SYSTEM ${BOOST_INCLUDE_DIR})
-      endif()
-    endif()
-  else()
-    find_package(Boost ${MIN_BOOST_VERSION}
-      COMPONENTS unit_test_framework
-      )
-
-    if (NOT Boost_UNIT_TEST_FRAMEWORK_FOUND)
-      # Check if we have header implementation available from
-      # extracted source tarball.
-      if (NOT WITH_BOOST)
-        message(FATAL_ERROR "System Boost not found, specify Boost installation with WITH_BOOST=<install_dir>")
-      endif()
-      CHECK_CXX_SOURCE_COMPILES(
-        "
-#define BOOST_TEST_ALTERNATIVE_INIT_API
-#include <boost/test/included/unit_test.hpp>
-bool init_unit_test() { return true; }
-"
-        FOUND_BOOST_TEST_INCLUDED_UNIT_TEST_HPP)
-      if (NOT FOUND_BOOST_TEST_INCLUDED_UNIT_TEST_HPP)
-        message(FATAL_ERROR "Boost unit test header not found")
-      endif()
-    endif()
-  endif()
-endif()
 
 if (WSREP_LIB_WITH_DBSIM)
   find_package(Boost ${MIN_BOOST_VERSION} REQUIRED

cmake/unittests.cmake

@@ -0,0 +1,87 @@
+# Copyright (c) 2024, Codership Oy.
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License, version 2.0,
+# as published by the Free Software Foundation.
+#
+# This program is also distributed with certain software (including
+# but not limited to OpenSSL) that is licensed under separate terms,
+# as designated in a particular file or component or in included license
+# documentation.  The authors of MySQL hereby grant you an additional
+# permission to link the program and your derivative works with the
+# separately licensed software that they have included with MySQL.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License, version 2.0, for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301  USA
+
+if (NOT WSREP_LIB_WITH_UNIT_TESTS)
+  return()
+endif()
+
+set(MIN_BOOST_VERSION "1.54.0")
+if (WSREP_LIB_WITH_UNIT_TESTS_EXTRA)
+  message(STATUS "Compiling extra unit tests")
+  set(json_HEADER "boost/json/src.hpp")
+  # Extra tests may require packages from very recent boost which may be
+  # unavailable on the system. In such case download private boost distro.
+  check_include_file_cxx(${json_HEADER} system_json_FOUND)
+  if (NOT system_json_FOUND)
+    if (NOT WITH_BOOST)
+      set(WITH_BOOST "${CMAKE_SOURCE_DIR}/third_party/boost")
+    endif()
+    set(DOWNLOAD_BOOST ON)
+    include (cmake/boost.cmake)
+    set(MIN_BOOST_VERSION "${BOOST_MAJOR}.${BOOST_MINOR}.${BOOST_PATCH}")
+    message(STATUS "Boost includes: ${BOOST_INCLUDE_DIR}, ver: ${MIN_BOOST_VERSION}")
+    find_package(Boost ${MIN_BOOST_VERSION} REQUIRED
+      COMPONENTS json headers unit_test_framework
+      PATHS ${WITH_BOOST}/lib/cmake
+      NO_DEFAULT_PATH
+      )
+    # Include as system header to be more permissive about generated
+    # warnings.
+    set(CMAKE_REQUIRED_FLAGS "-isystem ${BOOST_INCLUDE_DIR}")
+    check_include_file_cxx(${json_HEADER} json_FOUND)
+    if (NOT json_FOUND)
+      message(FATAL_ERROR "Required header 'boost/json.hpp' not found: ${json_FOUND}")
+    else()
+      include_directories(SYSTEM ${BOOST_INCLUDE_DIR})
+    endif()
+  endif()
+  return()
+endif() # WSREP_LIB_WITH_UNIT_TESTS_EXTRA
+
+# Superproject has already detected Boost. Most likely MySQL 8.0 or later.
+if (BOOST_INCLUDE_DIR)
+  message(STATUS "Boost include dir set to ${BOOST_INCLUDE_DIR}")
+  cmake_push_check_state()
+  list(APPEND CMAKE_REQUIRED_INCLUDES "${BOOST_INCLUDE_DIR}")
+  # Append -isystem to tolerate warnings from compiler
+  list(APPEND CMAKE_REQUIRED_FLAGS "-isystem ${BOOST_INCLUDE_DIR}")
+  check_cxx_source_compiles(
+    "
+#define BOOST_TEST_ALTERNATIVE_INIT_API
+#include <boost/test/included/unit_test.hpp>
+bool init_unit_test() { return true; }
+"
+    FOUND_BOOST_TEST_INCLUDED_UNIT_TEST_HPP)
+  if (NOT FOUND_BOOST_TEST_INCLUDED_UNIT_TEST_HPP)
+    message(FATAL_ERROR
+      "Boost unit test header file not found from ${CMAKE_REQUIRED_INCLUDES}")
+  endif()
+  cmake_pop_check_state()
+  include_directories(SYSTEM ${BOOST_INCLUDE_DIR})
+  return()
+endif() # BOOST_INCLUDE_DIR
+
+# System Boost.
+find_package(Boost ${MIN_BOOST_VERSION}
+  REQUIRED
+  COMPONENTS unit_test_framework
+  )