Use a console app for Qt5 unit testing so it can be run headless.

test cases/frameworks/4 qt5/main.cpp

@@ -10,9 +10,7 @@ int main(int argc, char **argv) {
   }
   win->setWindowTitle("Meson Qt5 build test");
 
-  // Don't actually start the GUI so this
-  // can be run as a unit test.
-  //win->show();
-  //return app.exec();
+  win->show();
+  return app.exec();
   return 0;
 }

test cases/frameworks/4 qt5/meson.build

@@ -2,11 +2,17 @@ project('qt5 build test', 'cpp')
 
 qt5dep = dependency('qt5', modules : 'Widgets')
 
-q5exe = executable('qt5test',
+q5exe = executable('qt5app',
 sources : ['main.cpp', 'mainWindow.cpp'], # Sources that don't need preprocessing.
 moc_headers : ['mainWindow.h'], # These need to be fed through the moc tool before use. 
 ui_files : 'mainWindow.ui', # XML files that need to be compiled with the uic tol.
 resources : 'stuff.qrc', # Resource file for rcc compiler.
 deps : qt5dep)
 
-test('qt5test', q5exe)
+# We need a console test application because some test environments
+# do not have an X server.
+
+q5core = executable('q5core', 'q5core.cpp',
+deps : dependency('qt5', modules : 'Core'))
+
+test('qt5test', q5core)

test cases/frameworks/4 qt5/q5core.cpp

@@ -0,0 +1,10 @@
+#include <QCoreApplication>
+
+int main(int argc, char **argv) {
+  QCoreApplication app(argc, argv);
+
+  // Don't actually start the main loop so this
+  // can be run as a unit test.
+  //return app.exec();
+  return 0;
+}