Make sure we load translations on the main thread.

Because the old implementation (accidentally) worked when you put the
ecm_create_qm_loader call in a different CMakeLists.txt file to the
target the file was added to, some projects did this.

This won't work with build-time-generated files, though, like moc files.
So we (ab)use QTimer events to make the loading happen on the main
thread.

BUG: 346188
REVIEW: 126000

1 files changed, 69 insertions, 0 deletions

diff --git a/tests/ECMPoQmToolsTest/tr_thread_test.cpp b/tests/ECMPoQmToolsTest/tr_thread_test.cpp
new file mode 100644
index 00000000..40e4d1eb
--- /dev/null
+++ b/tests/ECMPoQmToolsTest/tr_thread_test.cpp
@@ -0,0 +1,69 @@
+#include <QCoreApplication>
+#include <QLibrary>
+#include <QMetaObject>
+#include <QThread>
+
+class Thread : public QThread
+{
+    Q_OBJECT
+
+    QLibrary *m_lib;
+
+public:
+    Thread()
+        : m_lib(0)
+    {}
+    ~Thread()
+    {
+        delete m_lib;
+    }
+
+Q_SIGNALS:
+    void libraryLoaded();
+
+public Q_SLOTS:
+    void printStrings()
+    {
+        Q_ASSERT(QThread::currentThread() == QCoreApplication::instance()->thread());
+
+        QFunctionPointer print_strings = m_lib->resolve("print_strings");
+        if (print_strings) {
+            print_strings();
+        } else {
+            qFatal("Could not resolve print_strings: %s", qPrintable(m_lib->errorString()));
+        }
+
+        QCoreApplication::instance()->quit();
+    }
+protected:
+    void run()
+    {
+        m_lib = new QLibrary(MODULE_PATH);
+
+        if (!m_lib->load()) {
+            qFatal("Could not load module: %s", m_lib->errorString().toUtf8().data());
+        }
+
+        // Queue a call to printStrings() on the main event loop (giving the
+        // translations a chance to be loaded).
+        QMetaObject::invokeMethod(this, "printStrings", Qt::QueuedConnection);
+    }
+};
+
+int main(int argc, char** argv)
+{
+    QCoreApplication app(argc, argv);
+
+    Thread thread;
+
+    // Start the thread *after* QCoreApplication is started (otherwise the
+    // plugin's startup function won't be run on the Thread, and we won't test
+    // what we wanted to test).
+    QMetaObject::invokeMethod(&thread, "start", Qt::QueuedConnection);
+
+    app.exec();
+
+    return 0;
+}
+
+#include "tr_thread_test.moc"