Clangd: Handle settings changes

Users no longer have to re-load a project for settings changes to take
effect.

Change-Id: I86dccccac14a30514c8dac292c7765ee4806f6ba
Reviewed-by: David Schulz <david.schulz@qt.io>

src/plugins/cpptools/cppcodemodelsettings.cpp

@@ -303,18 +303,6 @@ void CppCodeModelSettings::setEnableLowerClazyLevels(bool yesno)
 }
 
 
-static bool operator==(const ClangdSettings::Data &s1, const ClangdSettings::Data &s2)
-{
-    return s1.useClangd == s2.useClangd
-            && s1.executableFilePath == s2.executableFilePath
-            && s1.workerThreadLimit == s2.workerThreadLimit
-            && s1.enableIndexing == s2.enableIndexing;
-}
-static bool operator!=(const ClangdSettings::Data &s1, const ClangdSettings::Data &s2)
-{
-    return !(s1 == s2);
-}
-
 ClangdSettings &ClangdSettings::instance()
 {
     static ClangdSettings settings;
@@ -338,6 +326,7 @@ void ClangdSettings::setData(const Data &data)
     if (this == &instance() && data != m_data) {
         m_data = data;
         saveSettings();
+        emit changed();
     }
 }
 
@@ -364,23 +353,25 @@ ClangdProjectSettings::ClangdProjectSettings(ProjectExplorer::Project *project)
     loadSettings();
 }
 
-ClangdSettings ClangdProjectSettings::settings() const
+ClangdSettings::Data ClangdProjectSettings::settings() const
 {
     if (m_useGlobalSettings)
-        return ClangdSettings::instance();
-    return ClangdSettings(m_customSettings);
+        return ClangdSettings::instance().data();
+    return m_customSettings;
 }
 
 void ClangdProjectSettings::setSettings(const ClangdSettings::Data &data)
 {
     m_customSettings = data;
     saveSettings();
+    emit ClangdSettings::instance().changed();
 }
 
 void ClangdProjectSettings::setUseGlobalSettings(bool useGlobal)
 {
     m_useGlobalSettings = useGlobal;
     saveSettings();
+    emit ClangdSettings::instance().changed();
 }
 
 void ClangdProjectSettings::loadSettings()

src/plugins/cpptools/cppcodemodelsettings.h

@@ -98,10 +98,11 @@ private:
     bool m_categorizeFindReferences = false; // Ephemeral!
 };
 
-class CPPTOOLS_EXPORT ClangdSettings
+class CPPTOOLS_EXPORT ClangdSettings : public QObject
 {
+    Q_OBJECT
 public:
-    class Data
+    class CPPTOOLS_EXPORT Data
     {
     public:
         QVariantMap toMap() const;
@@ -131,6 +132,9 @@ public:
     static void setClangdFilePath(const Utils::FilePath &filePath);
 #endif
 
+signals:
+    void changed();
+
 private:
     ClangdSettings() { loadSettings(); }
 
@@ -140,12 +144,24 @@ private:
     Data m_data;
 };
 
+inline bool operator==(const ClangdSettings::Data &s1, const ClangdSettings::Data &s2)
+{
+    return s1.useClangd == s2.useClangd
+            && s1.executableFilePath == s2.executableFilePath
+            && s1.workerThreadLimit == s2.workerThreadLimit
+            && s1.enableIndexing == s2.enableIndexing;
+}
+inline bool operator!=(const ClangdSettings::Data &s1, const ClangdSettings::Data &s2)
+{
+    return !(s1 == s2);
+}
+
 class CPPTOOLS_EXPORT ClangdProjectSettings
 {
 public:
     ClangdProjectSettings(ProjectExplorer::Project *project);
 
-    ClangdSettings settings() const;
+    ClangdSettings::Data settings() const;
     void setSettings(const ClangdSettings::Data &data);
     bool useGlobalSettings() const { return m_useGlobalSettings; }
     void setUseGlobalSettings(bool useGlobal);

src/plugins/cpptools/cppcodemodelsettingspage.cpp

@@ -200,12 +200,12 @@ public:
     Utils::PathChooser clangdChooser;
 };
 
-ClangdSettingsWidget::ClangdSettingsWidget(const ClangdSettings &settings) : d(new Private)
+ClangdSettingsWidget::ClangdSettingsWidget(const ClangdSettings::Data &settingsData)
+    : d(new Private)
 {
+    const ClangdSettings settings(settingsData);
     d->useClangdCheckBox.setText(tr("Use clangd (EXPERIMENTAL)"));
     d->useClangdCheckBox.setChecked(settings.useClangd());
-    d->useClangdCheckBox.setToolTip(tr("Changing this option does not affect projects "
-                                      "that are already open."));
     d->clangdChooser.setExpectedKind(Utils::PathChooser::ExistingCommand);
     d->clangdChooser.setFilePath(settings.clangdFilePath());
     d->clangdChooser.setEnabled(d->useClangdCheckBox.isChecked());
@@ -273,9 +273,8 @@ class ClangdSettingsPageWidget final : public Core::IOptionsPageWidget
     Q_DECLARE_TR_FUNCTIONS(CppTools::Internal::ClangdSettingsWidget)
 
 public:
-    ClangdSettingsPageWidget() : m_widget(ClangdSettings::instance())
+    ClangdSettingsPageWidget() : m_widget(ClangdSettings::instance().data())
     {
-
         const auto layout = new QVBoxLayout(this);
         layout->addWidget(&m_widget);
     }

src/plugins/cpptools/cppcodemodelsettingspage.h

@@ -49,7 +49,7 @@ class ClangdSettingsWidget : public QWidget
     Q_OBJECT
 
 public:
-    ClangdSettingsWidget(const ClangdSettings &settings);
+    ClangdSettingsWidget(const ClangdSettings::Data &settingsData);
     ~ClangdSettingsWidget();
 
     ClangdSettings::Data settingsData() const;