From c95cd5b147b7a7028b02584c77216441078bdec8 Mon Sep 17 00:00:00 2001
From: Arne Morten Kvarving <arne.morten.kvarving@sintef.no>
Date: Tue, 19 Dec 2023 10:34:24 +0100
Subject: [PATCH] added: bool param to flag that Main.hpp should not
 initialize/finalize MPI

needed for tests
---
 opm/simulators/flow/Main.cpp | 16 +++++++++++-----
 opm/simulators/flow/Main.hpp |  3 ++-
 2 files changed, 13 insertions(+), 6 deletions(-)

diff --git a/opm/simulators/flow/Main.cpp b/opm/simulators/flow/Main.cpp
index c75fef642..a9de12950 100644
--- a/opm/simulators/flow/Main.cpp
+++ b/opm/simulators/flow/Main.cpp
@@ -40,10 +40,12 @@
 
 namespace Opm {
 
-Main::Main(int argc, char** argv)
-    : argc_(argc), argv_(argv)
+Main::Main(int argc, char** argv, bool ownMPI)
+    : argc_(argc), argv_(argv), ownMPI_(ownMPI)
 {
-    initMPI();
+    if (ownMPI_) {
+        initMPI();
+    }
 }
 
 Main::Main(const std::string& filename)
@@ -83,7 +85,9 @@ Main::~Main()
     }
 #endif // HAVE_MPI
 
-    EclGenericVanguard::setCommunication(nullptr);
+    if (ownMPI_) {
+        EclGenericVanguard::setCommunication(nullptr);
+    }
 
 #if HAVE_DAMARIS
     if (enableDamarisOutput_) {
@@ -102,7 +106,9 @@ Main::~Main()
 #endif // HAVE_DAMARIS
 
 #if HAVE_MPI && !HAVE_DUNE_FEM
-    MPI_Finalize();
+    if (ownMPI_) {
+        MPI_Finalize();
+    }
 #endif
 }
 
diff --git a/opm/simulators/flow/Main.hpp b/opm/simulators/flow/Main.hpp
index 9b0487376..13125825d 100644
--- a/opm/simulators/flow/Main.hpp
+++ b/opm/simulators/flow/Main.hpp
@@ -127,7 +127,7 @@ int flowEbosMain(int argc, char** argv, bool outputCout, bool outputFiles)
 class Main
 {
 public:
-    Main(int argc, char** argv);
+    Main(int argc, char** argv, bool ownMPI = true);
 
     // This constructor can be called from Python
     Main(const std::string& filename);
@@ -727,6 +727,7 @@ private:
 
     int argc_{0};
     char** argv_{nullptr};
+    bool ownMPI_{true}; //!< True if we "own" MPI and should init / finalize
     bool outputCout_{false};
     bool outputFiles_{false};
     double setupTime_{0.0};