IWizardFactory: Factor out plugin feature set generation

Change-Id: I8e8c5ec691f7054e1c57994d3ee599a6942ddf8d
Reviewed-by: Daniel Teske <daniel.teske@digia.com>
Reviewed-by: Orgad Shaneh <orgads@gmail.com>

src/plugins/coreplugin/iwizardfactory.cpp

@@ -190,21 +190,7 @@ QList<IWizardFactory*> IWizardFactory::wizardFactoriesOfKind(WizardKind kind)
 
 bool IWizardFactory::isAvailable(const QString &platformName) const
 {
-    FeatureSet availableFeatures;
-
-    // Implicitly create a feature for each plugin loaded:
-    QList<ExtensionSystem::PluginSpec *> activeSpecs;
-    foreach (ExtensionSystem::PluginSpec *s, ExtensionSystem::PluginManager::plugins()) {
-        if (s->state() == ExtensionSystem::PluginSpec::Running)
-            activeSpecs << s;
-    }
-
-    QStringList plugins = Utils::transform(activeSpecs,
-                                           [](ExtensionSystem::PluginSpec *s) -> QString {
-                                               return QStringLiteral("Plugin.") + s->name();
-                                           });
-    foreach (const QString &n, plugins)
-        availableFeatures |= Feature(Core::Id::fromString(n));
+    FeatureSet availableFeatures = pluginFeatures();
 
     foreach (const Core::IFeatureProvider *featureManager, s_providerList)
         availableFeatures |= featureManager->availableFeatures(platformName);
@@ -255,3 +241,18 @@ void IWizardFactory::destroyFeatureProvider()
     qDeleteAll(s_providerList);
     s_providerList.clear();
 }
+
+FeatureSet IWizardFactory::pluginFeatures() const
+{
+    static FeatureSet plugins;
+    if (plugins.isEmpty()) {
+        QStringList list;
+        // Implicitly create a feature for each plugin loaded:
+        foreach (ExtensionSystem::PluginSpec *s, ExtensionSystem::PluginManager::plugins()) {
+            if (s->state() == ExtensionSystem::PluginSpec::Running)
+                list.append(QString::fromLatin1("Plugin.") + s->name());
+        }
+        plugins = FeatureSet::fromStringList(list);
+    }
+    return plugins;
+}

src/plugins/coreplugin/iwizardfactory.h

@@ -36,6 +36,7 @@
 
 #include <QIcon>
 #include <QObject>
+#include <QString>
 #include <QVariantMap>
 
 namespace Core {
@@ -98,6 +99,9 @@ public:
 
     static void registerFeatureProvider(IFeatureProvider *provider);
 
+protected:
+    Core::FeatureSet pluginFeatures() const;
+
 private:
     static void destroyFeatureProvider();