[Qt] Avoid QApplication duplication via test main()

platform/qt/config.cmake

@@ -54,8 +54,6 @@ endmacro()
 
 macro(mbgl_platform_test)
     target_sources(mbgl-test
-        PRIVATE test/src/main.cpp
-        PRIVATE platform/qt/test/qmapboxgl.cpp
         PRIVATE platform/default/mbgl/gl/headless_backend.cpp
         PRIVATE platform/default/mbgl/gl/headless_backend.hpp
         PRIVATE platform/default/mbgl/gl/headless_display.cpp
@@ -63,10 +61,12 @@ macro(mbgl_platform_test)
         PRIVATE platform/default/mbgl/gl/offscreen_view.cpp
         PRIVATE platform/default/mbgl/gl/offscreen_view.hpp
         PRIVATE platform/qt/test/headless_backend_qt.cpp
+        PRIVATE platform/qt/test/main.cpp
+        PRIVATE platform/qt/test/qmapboxgl.cpp
     )
 
     set_source_files_properties(
-        test/src/main.cpp
+        platform/qt/test/main.cpp
         PROPERTIES COMPILE_FLAGS -DWORK_DIRECTORY="${CMAKE_SOURCE_DIR}"
     )
 

platform/qt/src/run_loop.cpp

@@ -31,22 +31,6 @@ RunLoop* RunLoop::Get() {
 }
 
 RunLoop::RunLoop(Type type) : impl(std::make_unique<Impl>()) {
-    // XXX: We should probably throw an runtime exception
-    // here instead of creating a QCoreApplication which is
-    // way too intrusive. This is a hack mostly for the unit
-    // tests to work, as you always need a QCoreApplication
-    // prior to run a Qt app.
-    if (!QCoreApplication::instance()) {
-        static const char* argv[] = { "mbgl" };
-        static int argc = 1;
-
-        // We need to keep this around because it would otherwise crash
-        // on Qt4 due to a bug on QNetworkConfigurationManager when recreating
-        // a QCoreApplication: https://bugreports.qt.io/browse/QTBUG-36897
-        static auto* app = new QCoreApplication(argc, const_cast<char**>(argv));
-        Q_UNUSED(app);
-    }
-
     switch (type) {
     case Type::New:
         impl->loop = std::make_unique<QEventLoop>();
@@ -80,6 +64,7 @@ void RunLoop::push(std::shared_ptr<WorkTask> task) {
 }
 
 void RunLoop::run() {
+    assert(QCoreApplication::instance());
     MBGL_VERIFY_THREAD(tid);
 
     if (impl->type == Type::Default) {
@@ -90,6 +75,7 @@ void RunLoop::run() {
 }
 
 void RunLoop::stop() {
+    assert(QCoreApplication::instance());
     invoke([&] {
         if (impl->type == Type::Default) {
             QCoreApplication::instance()->exit();
@@ -100,6 +86,7 @@ void RunLoop::stop() {
 }
 
 void RunLoop::runOnce() {
+    assert(QCoreApplication::instance());
     MBGL_VERIFY_THREAD(tid);
 
     if (impl->type == Type::Default) {

platform/qt/test/headless_backend_qt.cpp

@@ -1,6 +1,5 @@
 #include <mbgl/gl/headless_backend.hpp>
 
-#include <QApplication>
 #include <QGLContext>
 #include <QGLWidget>
 
@@ -40,13 +39,6 @@ bool HeadlessBackend::hasDisplay() {
 
 void HeadlessBackend::createContext() {
     assert(!hasContext());
-
-    static const char* argv[] = { "mbgl" };
-    static int argc = 1;
-    static auto* app = new QApplication(argc, const_cast<char**>(argv));
-
-    Q_UNUSED(app);
-
     impl.reset(new QtImpl);
 }
 

platform/qt/test/main.cpp

@@ -0,0 +1,24 @@
+#include <QApplication>
+
+#include <mbgl/test.hpp>
+#include <unistd.h>
+#include <cstring>
+#include <cerrno>
+#include <cstdio>
+
+#define xstr(s) str(s)
+#define str(s) #s
+
+int main(int argc, char *argv[]) {
+    QApplication app(argc, argv);
+
+#ifdef WORK_DIRECTORY
+    const int result = chdir(xstr(WORK_DIRECTORY));
+    if (result != 0) {
+        fprintf(stderr, "failed to change directory: %s\n", strerror(errno));
+        return errno;
+    }
+#endif
+
+    return mbgl::runTests(argc, argv);
+}

platform/qt/test/qmapboxgl.cpp

@@ -10,7 +10,7 @@ class QMapboxGLTest : public QObject, public ::testing::Test {
     Q_OBJECT
 
 public:
-    QMapboxGLTest() : app(argc, const_cast<char**>(&argv)), map(nullptr, settings) {
+    QMapboxGLTest() : map(nullptr, settings) {
         connect(&map, SIGNAL(mapChanged(QMapboxGL::MapChange)),
                 this, SLOT(onMapChanged(QMapboxGL::MapChange)));
         connect(&map, SIGNAL(needsRendering()),
@@ -26,19 +26,15 @@ public:
     void runUntil(QMapboxGL::MapChange status) {
         changeCallback = [&](QMapboxGL::MapChange change) {
             if (change == status) {
-                app.exit();
+                qApp->exit();
                 changeCallback = nullptr;
             }
         };
 
-        app.exec();
+        qApp->exec();
     }
 
 private:
-    int argc = 1;
-    const char* argv = "mbgl-test";
-
-    QApplication app;
     QGLWidget widget;
 
 protected: