Cherry-picking some external run routines

Mostly from c6bcb85562 but trees have
diverged sufficiently that there are others mixed in.  This removes the
system() call on MacOS when opening a directory

common/CMakeLists.txt

@@ -327,6 +327,7 @@ set( COMMON_SRCS
     kiway_express.cpp
     kiway_holder.cpp
     kiway_player.cpp
+    launch_ext.cpp
     lib_id.cpp
     lib_table_base.cpp
     lib_table_keywords.cpp

common/launch_ext.cpp

@@ -0,0 +1,42 @@
+/*
+ * This program source code file is part of KiCad, a free EDA CAD application.
+ *
+ * Copyright (C) 2020 Jon Evans <jon@craftyjon.com>
+ * Copyright (C) 2020 KiCad Developers, see AUTHORS.txt for contributors.
+ *
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation, either version 3 of the License, or (at your
+ * option) any later version.
+ *
+ * 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 for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <gestfich.h>
+#include <launch_ext.h>
+
+
+void LaunchExternal( const wxString& aPath )
+{
+#ifdef __WXMAC__
+    wxExecute( wxString::Format( "open \"%s\"", aPath ) );
+#else
+    wxString path( aPath );
+
+#if !wxCHECK_VERSION( 3, 1, 0 )
+    // Quote in case there are spaces in the path.
+    // Not needed on 3.1.4, but needed in 3.0 versions
+    // Moreover, on Linux, on 3.1.4 wx version, adding quotes breaks
+    // wxLaunchDefaultApplication
+    AddDelimiterString( path );
+#endif
+
+    wxLaunchDefaultApplication( path );
+#endif
+}

include/launch_ext.h

@@ -0,0 +1,32 @@
+/*
+ * This program source code file is part of KiCad, a free EDA CAD application.
+ *
+ * Copyright (C) 2020 Jon Evans <jon@craftyjon.com>
+ * Copyright (C) 2020 KiCad Developers, see AUTHORS.txt for contributors.
+ *
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation, either version 3 of the License, or (at your
+ * option) any later version.
+ *
+ * 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 for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef LAUNCH_EXT_H
+#define LAUNCH_EXT_H
+
+class wxString;
+
+/**
+ * Launches the given file or folder in the host OS
+ * @param aPath is a path to a file or folder
+ */
+void LaunchExternal( const wxString& aPath );
+
+#endif

kicad/mainframe.cpp

@@ -40,6 +40,7 @@
 #include <build_version.h>
 #include <dialog_configure_paths.h>
 #include <dialog_edit_library_tables.h>
+#include <launch_ext.h>
 #include "pgm_kicad.h"
 #include "tree_project_frame.h"
 
@@ -536,21 +537,7 @@ void KICAD_MANAGER_FRAME::OnOpenFileInTextEditor( wxCommandEvent& event )
 void KICAD_MANAGER_FRAME::OnBrowseInFileExplorer( wxCommandEvent& event )
 {
     // open project directory in host OS's file explorer
-    wxString project_dir = Prj().GetProjectPath();
-
-#ifdef __WXMAC__
-    wxString msg;
-
-    // Quote in case there are spaces in the path.
-    msg.Printf( "open \"%s\"", project_dir );
-
-    system( msg.c_str() );
-#else
-    // Quote in case there are spaces in the path.
-    AddDelimiterString( project_dir );
-
-    wxLaunchDefaultApplication( project_dir );
-#endif
+    LaunchExternal( Prj().GetProjectPath() );
 }