test_kvtree_write_gather.c:3:10: mpi.h: No such file or directory

[tonyhutter]

Building master without MPI gives:

[ 47%] Building C object test/CMakeFiles/kvtree_write_gather_test.dir/test_kvtree_write_gather.c.o
/home/hutter/new-kvtree/test/test_kvtree_write_gather.c:3:10: fatal error: mpi.h: No such file or directory
    3 | #include "mpi.h"
      |          ^~~~~~~
compilation terminated.

This fixes it for me:

diff --git a/test/CMakeLists.txt b/test/CMakeLists.txt
index 7b76209..5bd817d 100644
--- a/test/CMakeLists.txt
+++ b/test/CMakeLists.txt
@@ -23,23 +23,24 @@ ADD_TEST(roundtrip_tests test_kvtree)
 # print test script
 FIND_PROGRAM(PRINT_TEST ${CMAKE_CURRENT_SOURCE_DIR}/print_test)
 ADD_TEST(NAME print_test COMMAND ${PRINT_TEST} ${PROJECT_BINARY_DIR}/src/kvtree_print_file ${CMAKE_CURRENT_SOURCE_DIR}/files)
-#ADD_TEST(NAME kvtree_bcast COMMAND "mpirun -np 2 ./kvtree_bcast_test)
+
+IF(MPI_FOUND)
 ADD_EXECUTABLE(kvtree_bcast_test test_kvtree_bcast.c)
 TARGET_LINK_LIBRARIES(kvtree_bcast_test ${KVTREE_EXTERNAL_LIBS} kvtree)
-#ADD_TEST(NAME kvtree_bcast_test COMMAND ${MPIEXEC} -n 3 ./kvtree_bcast_test)
 ADD_TEST(NAME kvtree_bcast_test COMMAND ${MPIEXEC} ${MPIEXEC_NUMPROC_FLAG} 3 ./kvtree_bcast_test)
+
 ADD_EXECUTABLE(kvtree_send_recv_test test_kvtree_send_recv.c)
 TARGET_LINK_LIBRARIES(kvtree_send_recv_test ${KVTREE_EXTERNAL_LIBS} kvtree)
-#ADD_TEST(NAME kvtree_send_recv_test COMMAND ${MPIEXEC} -n 3 ./kvtree_send_recv_test)
 ADD_TEST(NAME kvtree_send_recv_test COMMAND ${MPIEXEC} ${MPIEXEC_NUMPROC_FLAG} 3 ./kvtree_send_recv_test)
+
 ADD_EXECUTABLE(kvtree_exchange_test test_kvtree_exchange.c)
 TARGET_LINK_LIBRARIES(kvtree_exchange_test ${KVTREE_EXTERNAL_LIBS} kvtree)
-#ADD_TEST(NAME kvtree_exchange_test COMMAND ${MPIEXEC} -n 3 ./kvtree_exchange_test)
 ADD_TEST(NAME kvtree_exchange_test COMMAND ${MPIEXEC} ${MPIEXEC_NUMPROC_FLAG} 3 ./kvtree_exchange_test)
+
 ADD_EXECUTABLE(kvtree_write_gather_test test_kvtree_write_gather.c)
 TARGET_LINK_LIBRARIES(kvtree_write_gather_test ${KVTREE_EXTERNAL_LIBS} kvtree)
-#ADD_TEST(NAME kvtree_write_gather_test COMMAND ${MPIEXEC} -n 3 ./kvtree_write_gather_test
 ADD_TEST(NAME kvtree_write_gather_test COMMAND ${MPIEXEC} ${MPIEXEC_NUMPROC_FLAG} 3 ./kvtree_write_gather_test)
+ENDIF(MPI_FOUND)

I havn't tested it yet with MPI to see if that still works.