CppTools: Add dedicated settings and settings page for clangd

We plan to add more clangd settings, and it makes sense to have a
dedicated place for them both in the code and the UI.

Change-Id: Ideb92935b7a5a6a98e07980f4011736fb82042d1
Reviewed-by: David Schulz <david.schulz@qt.io>

6 files changed, 153 insertions, 70 deletions

diff --git a/src/plugins/cpptools/cppcodemodelsettings.cpp b/src/plugins/cpptools/cppcodemodelsettings.cpp
index 5c5113d004..aa09d40918 100644
--- a/src/plugins/cpptools/cppcodemodelsettings.cpp
+++ b/src/plugins/cpptools/cppcodemodelsettings.cpp
@@ -29,6 +29,8 @@
 #include "cpptoolsconstants.h"
 #include "cpptoolsreuse.h"
 
+#include <coreplugin/icore.h>
+
 #include <utils/algorithm.h>
 #include <utils/qtcassert.h>
 
@@ -172,9 +174,6 @@ void CppCodeModelSettings::fromSettings(QSettings *s)
     const QVariant indexerFileSizeLimit = s->value(indexerFileSizeLimitKey(), 5);
     setIndexerFileSizeLimitInMb(indexerFileSizeLimit.toInt());
 
-    setUseClangd(s->value(useClangdKey(), false).toBool());
-    setClangdFilePath(FilePath::fromString(s->value(clangdPathKey()).toString()));
-
     s->endGroup();
 
     if (write)
@@ -198,8 +197,6 @@ void CppCodeModelSettings::toSettings(QSettings *s)
     s->setValue(interpretAmbiguousHeadersAsCHeadersKey(), interpretAmbigiousHeadersAsCHeaders());
     s->setValue(skipIndexingBigFilesKey(), skipIndexingBigFiles());
     s->setValue(indexerFileSizeLimitKey(), indexerFileSizeLimitInMb());
-    s->setValue(useClangdKey(), useClangd());
-    s->setValue(clangdPathKey(), m_clangdFilePath.toString());
 
     s->endGroup();
 
@@ -300,14 +297,60 @@ void CppCodeModelSettings::setEnableLowerClazyLevels(bool yesno)
     m_enableLowerClazyLevels = yesno;
 }
 
-void CppCodeModelSettings::setDefaultClangdPath(const Utils::FilePath &filePath)
+
+static bool operator==(const ClangdSettings::Data &s1, const ClangdSettings::Data &s2)
+{
+    return s1.useClangd == s2.useClangd && s1.executableFilePath == s2.executableFilePath;
+}
+static bool operator!=(const ClangdSettings::Data &s1, const ClangdSettings::Data &s2)
+{
+    return !(s1 == s2);
+}
+
+ClangdSettings &ClangdSettings::instance()
+{
+    static ClangdSettings settings;
+    return settings;
+}
+
+void ClangdSettings::setDefaultClangdPath(const Utils::FilePath &filePath)
 {
     g_defaultClangdFilePath = filePath;
 }
 
-FilePath CppCodeModelSettings::clangdFilePath() const
+FilePath ClangdSettings::clangdFilePath()
 {
-    if (!m_clangdFilePath.isEmpty())
-        return m_clangdFilePath;
+    if (!instance().m_data.executableFilePath.isEmpty())
+        return instance().m_data.executableFilePath;
     return fallbackClangdFilePath();
 }
+
+void ClangdSettings::setData(const Data &data)
+{
+    if (data != instance().m_data) {
+        instance().m_data = data;
+        instance().saveSettings();
+    }
+}
+
+void ClangdSettings::loadSettings()
+{
+    QSettings * const s = Core::ICore::settings();
+    m_data.useClangd = s->value(useClangdKey(), false).toBool();
+    m_data.executableFilePath = FilePath::fromString(s->value(clangdPathKey()).toString());
+}
+
+void ClangdSettings::saveSettings()
+{
+    QSettings * const s = Core::ICore::settings();
+    s->setValue(useClangdKey(), useClangd());
+    s->setValue(clangdPathKey(), m_data.executableFilePath.toString());
+}
+
+#ifdef WITH_TESTS
+void ClangdSettings::setUseClangd(bool use) { instance().m_data.useClangd = use; }
+void ClangdSettings::setClangdFilePath(const Utils::FilePath &filePath)
+{
+    instance().m_data.executableFilePath = filePath;
+}
+#endif
diff --git a/src/plugins/cpptools/cppcodemodelsettings.h b/src/plugins/cpptools/cppcodemodelsettings.h
index 5fc981e543..a84d20186f 100644
--- a/src/plugins/cpptools/cppcodemodelsettings.h
+++ b/src/plugins/cpptools/cppcodemodelsettings.h
@@ -78,13 +78,6 @@ public:
     int indexerFileSizeLimitInMb() const;
     void setIndexerFileSizeLimitInMb(int sizeInMB);
 
-    void setUseClangd(bool use) { m_useClangd = use; }
-    bool useClangd() const { return m_useClangd; }
-
-    static void setDefaultClangdPath(const Utils::FilePath &filePath);
-    void setClangdFilePath(const Utils::FilePath &filePath) { m_clangdFilePath = filePath; }
-    Utils::FilePath clangdFilePath() const;
-
     void setCategorizeFindReferences(bool categorize) { m_categorizeFindReferences = categorize; }
     bool categorizeFindReferences() const { return m_categorizeFindReferences; }
 
@@ -100,9 +93,40 @@ private:
     ClangDiagnosticConfigs m_clangCustomDiagnosticConfigs;
     Utils::Id m_clangDiagnosticConfigId;
     bool m_enableLowerClazyLevels = true; // For UI behavior only
-    Utils::FilePath m_clangdFilePath;
-    bool m_useClangd = false;
     bool m_categorizeFindReferences = false; // Ephemeral!
 };
 
+class CPPTOOLS_EXPORT ClangdSettings
+{
+public:
+    class Data
+    {
+    public:
+        bool useClangd = false;
+        Utils::FilePath executableFilePath;
+    };
+
+    static bool useClangd() { return instance().m_data.useClangd; }
+
+    static void setDefaultClangdPath(const Utils::FilePath &filePath);
+    static Utils::FilePath clangdFilePath();
+
+    static void setData(const Data &data);
+    static Data data() { return instance().m_data; }
+
+#ifdef WITH_TESTS
+    static void setUseClangd(bool use);
+    static void setClangdFilePath(const Utils::FilePath &filePath);
+#endif
+
+private:
+    ClangdSettings() { loadSettings(); }
+    static ClangdSettings &instance();
+
+    void loadSettings();
+    void saveSettings();
+
+    Data m_data;
+};
+
 } // namespace CppTools
diff --git a/src/plugins/cpptools/cppcodemodelsettingspage.cpp b/src/plugins/cpptools/cppcodemodelsettingspage.cpp
index 00e7b8081a..7d9fc2078e 100644
--- a/src/plugins/cpptools/cppcodemodelsettingspage.cpp
+++ b/src/plugins/cpptools/cppcodemodelsettingspage.cpp
@@ -33,7 +33,9 @@
 
 #include <coreplugin/icore.h>
 #include <utils/algorithm.h>
+#include <utils/pathchooser.h>
 
+#include <QFormLayout>
 #include <QTextStream>
 
 namespace CppTools {
@@ -100,8 +102,6 @@ void CppCodeModelSettingsWidget::setupClangCodeModelWidgets()
     const bool isClangActive = CppModelManager::instance()->isClangCodeModelActive();
     m_ui->clangCodeModelIsDisabledHint->setVisible(!isClangActive);
     m_ui->clangCodeModelIsEnabledHint->setVisible(isClangActive);
-    m_ui->clangdCheckBox->setVisible(isClangActive);
-    m_ui->clangdChooser->setVisible(isClangActive);
 
     for (int i = 0; i < m_ui->clangDiagnosticConfigsSelectionWidget->layout()->count(); ++i) {
         QWidget *widget = m_ui->clangDiagnosticConfigsSelectionWidget->layout()->itemAt(i)->widget();
@@ -120,16 +120,6 @@ void CppCodeModelSettingsWidget::setupGeneralWidgets()
 
     const bool ignorePch = m_settings->pchUsage() == CppCodeModelSettings::PchUse_None;
     m_ui->ignorePCHCheckBox->setChecked(ignorePch);
-
-    m_ui->clangdCheckBox->setChecked(m_settings->useClangd());
-    m_ui->clangdCheckBox->setToolTip(tr("Use clangd for locators and \"Find References\".\n"
-        "Changing this option does not affect projects that are already open."));
-    m_ui->clangdChooser->setExpectedKind(Utils::PathChooser::ExistingCommand);
-    m_ui->clangdChooser->setFilePath(codeModelSettings()->clangdFilePath());
-    m_ui->clangdChooser->setEnabled(m_ui->clangdCheckBox->isChecked());
-    connect(m_ui->clangdCheckBox, &QCheckBox::toggled, m_ui->clangdChooser, [this](bool checked) {
-        m_ui->clangdChooser->setEnabled(checked);
-    });
 }
 
 bool CppCodeModelSettingsWidget::applyClangCodeModelWidgetsToSettings() const
@@ -176,16 +166,6 @@ bool CppCodeModelSettingsWidget::applyGeneralWidgetsToSettings() const
         m_settings->setIndexerFileSizeLimitInMb(newFileSizeLimit);
         settingsChanged = true;
     }
-    const bool newUseClangd = m_ui->clangdCheckBox->isChecked();
-    if (m_settings->useClangd() != newUseClangd) {
-        m_settings->setUseClangd(newUseClangd);
-        settingsChanged = true;
-    }
-    const Utils::FilePath newClangdPath = m_ui->clangdChooser->rawFilePath();
-    if (m_settings->clangdFilePath() != newClangdPath) {
-        m_settings->setClangdFilePath(newClangdPath);
-        settingsChanged = true;
-    }
 
     const bool newIgnorePch = m_ui->ignorePCHCheckBox->isChecked();
     const bool previousIgnorePch = m_settings->pchUsage() == CppCodeModelSettings::PchUse_None;
@@ -210,5 +190,60 @@ CppCodeModelSettingsPage::CppCodeModelSettingsPage(CppCodeModelSettings *setting
     setWidgetCreator([settings] { return new CppCodeModelSettingsWidget(settings); });
 }
 
+
+class ClangdSettingsWidget final : public Core::IOptionsPageWidget
+{
+    Q_DECLARE_TR_FUNCTIONS(CppTools::Internal::ClangdSettingsWidget)
+
+public:
+    ClangdSettingsWidget()
+    {
+        m_useClangdCheckBox.setText(tr("Use clangd (EXPERIMENTAL)"));
+        m_useClangdCheckBox.setChecked(ClangdSettings::useClangd());
+        m_useClangdCheckBox.setToolTip(tr("Changing this option does not affect projects "
+                                          "that are already open."));
+        m_clangdChooser.setExpectedKind(Utils::PathChooser::ExistingCommand);
+        m_clangdChooser.setFilePath(ClangdSettings::clangdFilePath());
+        m_clangdChooser.setEnabled(m_useClangdCheckBox.isChecked());
+
+        const auto layout = new QVBoxLayout(this);
+        layout->addWidget(&m_useClangdCheckBox);
+        const auto formLayout = new QFormLayout;
+        const auto chooserLabel = new QLabel(tr("Path to executable:"));
+        formLayout->addRow(chooserLabel, &m_clangdChooser);
+        layout->addLayout(formLayout);
+        layout->addStretch(1);
+
+        const auto toggleEnabled = [=](const bool checked) {
+            chooserLabel->setEnabled(checked);
+            m_clangdChooser.setEnabled(checked);
+        };
+        connect(&m_useClangdCheckBox, &QCheckBox::toggled, toggleEnabled);
+        toggleEnabled(m_useClangdCheckBox.isChecked());
+    }
+
+private:
+    void apply() final
+    {
+        ClangdSettings::Data data;
+        data.useClangd = m_useClangdCheckBox.isChecked();
+        data.executableFilePath = m_clangdChooser.filePath();
+        ClangdSettings::setData(data);
+    }
+
+    QCheckBox m_useClangdCheckBox;
+    Utils::PathChooser m_clangdChooser;
+};
+
+ClangdSettingsPage::ClangdSettingsPage()
+{
+    setId("K.Clangd");
+    setDisplayName(ClangdSettingsWidget::tr("Clangd"));
+    setCategory(Constants::CPP_SETTINGS_CATEGORY);
+    setWidgetCreator([] { return new ClangdSettingsWidget; });
+}
+
+
+
 } // Internal
 } // CppTools
diff --git a/src/plugins/cpptools/cppcodemodelsettingspage.h b/src/plugins/cpptools/cppcodemodelsettingspage.h
index dd297af020..5e48be1ffe 100644
--- a/src/plugins/cpptools/cppcodemodelsettingspage.h
+++ b/src/plugins/cpptools/cppcodemodelsettingspage.h
@@ -38,5 +38,11 @@ public:
     explicit CppCodeModelSettingsPage(CppCodeModelSettings *settings);
 };
 
+class ClangdSettingsPage final : public Core::IOptionsPage
+{
+public:
+    explicit ClangdSettingsPage();
+};
+
 } // Internal namespace
 } // CppTools namespace
diff --git a/src/plugins/cpptools/cppcodemodelsettingspage.ui b/src/plugins/cpptools/cppcodemodelsettingspage.ui
index 2362131cbe..90136f81bd 100644
--- a/src/plugins/cpptools/cppcodemodelsettingspage.ui
+++ b/src/plugins/cpptools/cppcodemodelsettingspage.ui
@@ -81,31 +81,7 @@
        </layout>
       </item>
       <item>
-       <layout class="QHBoxLayout" name="horizontalLayout_3">
-        <item>
-         <widget class="QCheckBox" name="clangdCheckBox">
-          <property name="text">
-           <string>Use clangd (EXPERIMENTAL)</string>
-          </property>
-         </widget>
-        </item>
-        <item>
-         <widget class="Utils::PathChooser" name="clangdChooser"/>
-        </item>
-        <item>
-         <spacer name="horizontalSpacer_3">
-          <property name="orientation">
-           <enum>Qt::Horizontal</enum>
-          </property>
-          <property name="sizeHint" stdset="0">
-           <size>
-            <width>40</width>
-            <height>20</height>
-           </size>
-          </property>
-         </spacer>
-        </item>
-       </layout>
+       <layout class="QHBoxLayout" name="horizontalLayout_3"/>
       </item>
      </layout>
     </widget>
@@ -174,11 +150,6 @@
    <extends>QWidget</extends>
    <header>cpptools/clangdiagnosticconfigsselectionwidget.h</header>
   </customwidget>
-  <customwidget>
-   <class>Utils::PathChooser</class>
-   <extends>QLineEdit</extends>
-   <header location="global">utils/pathchooser.h</header>
-  </customwidget>
  </customwidgets>
  <resources/>
  <connections/>
diff --git a/src/plugins/cpptools/cpptoolsplugin.cpp b/src/plugins/cpptools/cpptoolsplugin.cpp
index c5796e0dba..87ecc25d71 100644
--- a/src/plugins/cpptools/cpptoolsplugin.cpp
+++ b/src/plugins/cpptools/cpptoolsplugin.cpp
@@ -86,6 +86,7 @@ public:
     ~CppToolsPluginPrivate()
     {
         ExtensionSystem::PluginManager::removeObject(&m_cppProjectUpdaterFactory);
+        delete m_clangdSettingsPage;
     }
 
     StringTable stringTable;
@@ -95,6 +96,7 @@ public:
     CppFileSettings m_fileSettings;
     CppFileSettingsPage m_cppFileSettingsPage{&m_fileSettings};
     CppCodeModelSettingsPage m_cppCodeModelSettingsPage{&m_codeModelSettings};
+    ClangdSettingsPage *m_clangdSettingsPage = nullptr;
     CppCodeStyleSettingsPage m_cppCodeStyleSettingsPage;
     CppProjectUpdaterFactory m_cppProjectUpdaterFactory;
 };
@@ -218,6 +220,8 @@ void CppToolsPlugin::extensionsInitialized()
     d->m_fileSettings.fromSettings(ICore::settings());
     if (!d->m_fileSettings.applySuffixesToMimeDB())
         qWarning("Unable to apply cpp suffixes to mime database (cpp mime types not found).\n");
+    if (CppModelManager::instance()->isClangCodeModelActive())
+        d->m_clangdSettingsPage = new ClangdSettingsPage;
 }
 
 CppCodeModelSettings *CppToolsPlugin::codeModelSettings()