ExtensionSystem: Allow opt-in plugin loading without restart

Change-Id: I682e51d047c43ff5bf4647ef7e015222707f3204
Reviewed-by: Marcus Tillmanns <marcus.tillmanns@qt.io>
Reviewed-by: Eike Ziller <eike.ziller@qt.io>

src/libs/extensionsystem/pluginmanager.cpp

@@ -322,6 +322,13 @@ void PluginManager::loadPlugins()
     d->loadPlugins();
 }
 
+void PluginManager::loadPlugin(PluginSpec *spec)
+{
+    d->loadPlugin(spec, PluginSpec::Loaded);
+    d->loadPlugin(spec, PluginSpec::Initialized);
+    d->loadPlugin(spec, PluginSpec::Running);
+}
+
 /*!
     Returns \c true if any plugin has errors even though it is enabled.
     Most useful to call after loadPlugins().
@@ -1616,17 +1623,19 @@ void PluginManagerPrivate::loadPlugin(PluginSpec *spec, PluginSpec::State destSt
         break;
     }
     // check if dependencies have loaded without error
-    const QHash<PluginDependency, PluginSpec *> deps = spec->dependencySpecs();
+    if (!spec->isSoftLoadable()) {
-    for (auto it = deps.cbegin(), end = deps.cend(); it != end; ++it) {
+        const QHash<PluginDependency, PluginSpec *> deps = spec->dependencySpecs();
-        if (it.key().type != PluginDependency::Required)
+        for (auto it = deps.cbegin(), end = deps.cend(); it != end; ++it) {
-            continue;
+            if (it.key().type != PluginDependency::Required)
-        PluginSpec *depSpec = it.value();
+                continue;
-        if (depSpec->state() != destState) {
+            PluginSpec *depSpec = it.value();
-            spec->d->hasError = true;
+            if (depSpec->state() != destState) {
-            spec->d->errorString =
+                spec->d->hasError = true;
-                Tr::tr("Cannot load plugin because dependency failed to load: %1(%2)\nReason: %3")
+                spec->d->errorString =
-                    .arg(depSpec->name(), depSpec->version(), depSpec->errorString());
+                    Tr::tr("Cannot load plugin because dependency failed to load: %1(%2)\nReason: %3")
-            return;
+                        .arg(depSpec->name(), depSpec->version(), depSpec->errorString());
+                return;
+            }
         }
     }
     switch (destState) {

src/libs/extensionsystem/pluginmanager.h

@@ -68,6 +68,7 @@ public:
     // Plugin operations
     static QVector<PluginSpec *> loadQueue();
     static void loadPlugins();
+    static void loadPlugin(PluginSpec *);
     static QStringList pluginPaths();
     static void setPluginPaths(const QStringList &paths);
     static QString pluginIID();

src/libs/extensionsystem/pluginspec.cpp

@@ -386,6 +386,11 @@ bool PluginSpec::isForceDisabled() const
     return d->forceDisabled;
 }
 
+bool PluginSpec::isSoftLoadable() const
+{
+    return d->softLoadable;
+}
+
 /*!
     The plugin dependencies. This is valid after the PluginSpec::Read state is reached.
 */
@@ -570,6 +575,7 @@ namespace {
     const char PLUGIN_REQUIRED[] = "Required";
     const char PLUGIN_EXPERIMENTAL[] = "Experimental";
     const char PLUGIN_DISABLED_BY_DEFAULT[] = "DisabledByDefault";
+    const char PLUGIN_SOFTLOADABLE[] = "SoftLoadable";
     const char VENDOR[] = "Vendor";
     const char COPYRIGHT[] = "Copyright";
     const char LICENSE[] = "License";
@@ -683,6 +689,11 @@ void PluginSpecPrivate::setForceDisabled(bool value)
     forceDisabled = value;
 }
 
+void PluginSpecPrivate::setSoftLoadable(bool value)
+{
+    softLoadable = value;
+}
+
 /*!
     \internal
 */
@@ -796,6 +807,12 @@ bool PluginSpecPrivate::readMetaData(const QJsonObject &pluginMetaData)
         enabledByDefault = false;
     enabledBySettings = enabledByDefault;
 
+    value = metaData.value(QLatin1String(PLUGIN_SOFTLOADABLE));
+    if (!value.isUndefined() && !value.isBool())
+        return reportError(msgValueIsNotABool(PLUGIN_SOFTLOADABLE));
+    softLoadable = value.toBool(false);
+    qCDebug(pluginLog) << "softLoadable =" << softLoadable;
+
     value = metaData.value(QLatin1String(VENDOR));
     if (!value.isUndefined() && !value.isString())
         return reportError(msgValueIsNotAString(VENDOR));

src/libs/extensionsystem/pluginspec.h

@@ -100,6 +100,7 @@ public:
     bool isEnabledIndirectly() const;
     bool isForceEnabled() const;
     bool isForceDisabled() const;
+    bool isSoftLoadable() const;
     QVector<PluginDependency> dependencies() const;
     QJsonObject metaData() const;
     const PerformanceData &performanceData() const;

src/libs/extensionsystem/pluginspec_p.h

@@ -45,6 +45,7 @@ public:
     void setEnabledByDefault(bool value);
     void setForceEnabled(bool value);
     void setForceDisabled(bool value);
+    void setSoftLoadable(bool value);
 
     std::optional<QPluginLoader> loader;
     std::optional<QStaticPlugin> staticPlugin;
@@ -69,6 +70,7 @@ public:
     bool enabledIndirectly = false;
     bool forceEnabled = false;
     bool forceDisabled = false;
+    bool softLoadable = false;
 
     QString location;
     QString filePath;

src/libs/extensionsystem/pluginview.cpp

@@ -237,9 +237,7 @@ public:
         if (column == LoadedColumn && role == Qt::CheckStateRole) {
             const QVector<PluginSpec *> affectedPlugins
                 = Utils::filtered(m_plugins, [](PluginSpec *spec) { return !spec->isRequired(); });
-            if (m_view->setPluginsEnabled(Utils::transform<QSet>(affectedPlugins,
+            if (m_view->setPluginsEnabled(toSet(affectedPlugins), data.toBool())) {
-                                                                 [](PluginSpec *s) { return s; }),
-                                          data.toBool())) {
                 update();
                 return true;
             }
@@ -419,8 +417,8 @@ bool PluginView::setPluginsEnabled(const QSet<PluginSpec *> &plugins, bool enabl
         spec->d->setEnabledBySettings(enable);
         item->updateColumn(LoadedColumn);
         item->parent()->updateColumn(LoadedColumn);
-        emit pluginSettingsChanged(spec);
     }
+    emit pluginsChanged(affectedPlugins, enable);
     return true;
 }
 

src/libs/extensionsystem/pluginview.h

@@ -7,6 +7,7 @@
 
 #include <utils/treemodel.h>
 
+#include <QSet>
 #include <QWidget>
 
 #include <unordered_map>
@@ -40,7 +41,7 @@ public:
 signals:
     void currentPluginChanged(ExtensionSystem::PluginSpec *spec);
     void pluginActivated(ExtensionSystem::PluginSpec *spec);
-    void pluginSettingsChanged(ExtensionSystem::PluginSpec *spec);
+    void pluginsChanged(const QSet<ExtensionSystem::PluginSpec *> &spec, bool enabled);
 
 private:
     PluginSpec *pluginForIndex(const QModelIndex &index) const;

src/plugins/coreplugin/plugindialog.cpp

@@ -14,6 +14,7 @@
 #include <extensionsystem/pluginspec.h>
 #include <extensionsystem/pluginview.h>
 
+#include <utils/algorithm.h>
 #include <utils/fancylineedit.h>
 #include <utils/layoutbuilder.h>
 
@@ -21,6 +22,7 @@
 #include <QDialogButtonBox>
 #include <QPushButton>
 
+using namespace ExtensionSystem;
 using namespace Utils;
 
 namespace Core {
@@ -59,8 +61,16 @@ PluginDialog::PluginDialog(QWidget *parent)
             this, &PluginDialog::updateButtons);
     connect(m_view, &ExtensionSystem::PluginView::pluginActivated,
             this, &PluginDialog::openDetails);
-    connect(m_view, &ExtensionSystem::PluginView::pluginSettingsChanged, this, [this] {
+    connect(m_view, &ExtensionSystem::PluginView::pluginsChanged,
-        m_isRestartRequired = true;
+            this, [this](const QSet<PluginSpec *> &plugins, bool enable) {
+        for (PluginSpec *plugin : plugins) {
+            if (enable && plugin->isSoftLoadable()) {
+                m_softLoad.insert(plugin);
+            } else {
+                m_softLoad.remove(plugin); // In case it was added, harmless otherwise.
+                m_isRestartRequired = true;
+            }
+        }
     });
     connect(m_detailsButton, &QAbstractButton::clicked, this,
             [this]  { openDetails(m_view->currentPlugin()); });
@@ -75,7 +85,11 @@ PluginDialog::PluginDialog(QWidget *parent)
 
 void PluginDialog::closeDialog()
 {
-    ExtensionSystem::PluginManager::writeSettings();
+    PluginManager::writeSettings();
+
+    for (PluginSpec *plugin : m_softLoad)
+        PluginManager::loadPlugin(plugin);
+
     if (m_isRestartRequired) {
         RestartDialog restartDialog(ICore::dialogParent(),
                                     Tr::tr("Plugin changes will take effect after restart."));

src/plugins/coreplugin/plugindialog.h

@@ -38,6 +38,7 @@ private:
     QPushButton *m_errorDetailsButton;
     QPushButton *m_installButton;
     bool m_isRestartRequired = false;
+    QSet<ExtensionSystem::PluginSpec *> m_softLoad;
 };
 
 } // namespace Internal