From 0d0bd1168bb96ded8dfe5ab3ca60588dec5d2949 Mon Sep 17 00:00:00 2001
From: wmayer <wmayer@users.sourceforge.net>
Date: Thu, 28 Apr 2022 12:58:58 +0200
Subject: [PATCH] Mesh: handle exceptions when running FreeCAD in headless mode

---
 src/Mod/Mesh/Gui/AppMeshGui.cpp               | 5 ++++-
 src/Mod/MeshPart/Gui/MeshFlatteningCommand.py | 3 +++
 2 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/src/Mod/Mesh/Gui/AppMeshGui.cpp b/src/Mod/Mesh/Gui/AppMeshGui.cpp
index d06e3d6f0a..9f8ab0a3be 100644
--- a/src/Mod/Mesh/Gui/AppMeshGui.cpp
+++ b/src/Mod/Mesh/Gui/AppMeshGui.cpp
@@ -27,6 +27,7 @@
 # include <Inventor/SoInput.h>
 # include <Inventor/nodes/SoSeparator.h>
 # include <Inventor/annex/ForeignFiles/SoSTLFileKit.h>
+# include <QApplication>
 #endif
 
 #include <Base/Interpreter.h>
@@ -147,7 +148,9 @@ PyMOD_INIT_FUNC(MeshGui)
 
     // instantiating the commands
     CreateMeshCommands();
-    (void)new MeshGui::CleanupHandler;
+    if (qApp) {
+        (void)new MeshGui::CleanupHandler;
+    }
     
     // try to instantiate flat-mesh commands
     try{
diff --git a/src/Mod/MeshPart/Gui/MeshFlatteningCommand.py b/src/Mod/MeshPart/Gui/MeshFlatteningCommand.py
index 3b4a910de4..86eb8b8fbe 100644
--- a/src/Mod/MeshPart/Gui/MeshFlatteningCommand.py
+++ b/src/Mod/MeshPart/Gui/MeshFlatteningCommand.py
@@ -117,3 +117,6 @@ try:
 except ImportError:
     App.Console.PrintLog("flatmesh-commands are not available\n")
     App.Console.PrintLog("flatmesh needs pybind11 as build dependency\n")
+except AttributeError:
+    # Can happen when running FreeCAD in headless mode
+    pass