Fix reloading of plugins

Unloading and reloading a plugin didn't work correctly,
because we didn't reset instance to 0 on unload.

Task-number: QTBUG-26098
Change-Id: Ic3e4497f359b1ca455be949dce9cafa9d67d8039
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>

1 files changed, 24 insertions, 0 deletions

diff --git a/tests/auto/corelib/plugin/qpluginloader/tst_qpluginloader.cpp b/tests/auto/corelib/plugin/qpluginloader/tst_qpluginloader.cpp
index b79479ace8..58081cc6e3 100644
--- a/tests/auto/corelib/plugin/qpluginloader/tst_qpluginloader.cpp
+++ b/tests/auto/corelib/plugin/qpluginloader/tst_qpluginloader.cpp
@@ -109,6 +109,7 @@ private slots:
     void loadDebugObj();
     void loadCorruptElf();
     void loadGarbage();
+    void reloadPlugin();
 };
 
 void tst_QPluginLoader::errorString()
@@ -291,5 +292,28 @@ void tst_QPluginLoader::loadGarbage()
 #endif
 }
 
+void tst_QPluginLoader::reloadPlugin()
+{
+    QPluginLoader loader;
+    loader.setFileName( sys_qualifiedLibraryName("theplugin"));     //a plugin
+    loader.load(); // not recommended, instance() should do the job.
+    PluginInterface *instance = qobject_cast<PluginInterface*>(loader.instance());
+    QVERIFY(instance);
+    QCOMPARE(instance->pluginName(), QLatin1String("Plugin ok"));
+
+    QSignalSpy spy(loader.instance(), SIGNAL(destroyed()));
+    QVERIFY(spy.isValid());
+    QVERIFY(loader.unload());   // refcount reached 0, did really unload
+    QCOMPARE(spy.count(), 1);
+
+    // reload plugin
+    QVERIFY(loader.load());
+    QVERIFY(loader.isLoaded());
+
+    PluginInterface *instance2 = qobject_cast<PluginInterface*>(loader.instance());
+    QVERIFY(instance2);
+    QCOMPARE(instance2->pluginName(), QLatin1String("Plugin ok"));
+}
+
 QTEST_MAIN(tst_QPluginLoader)
 #include "tst_qpluginloader.moc"