[calamares] Refactor Settings initialization

- add a Settings::init() to do actual work
 - remove the same kind of code from CalamaresApplication
 - make constructor of Settings private
 - initialize settings before the application

src/calamares/CalamaresApplication.cpp

@@ -76,7 +76,11 @@ CalamaresApplication::init()
     cDebug() << "Calamares version:" << CALAMARES_VERSION;
     cDebug() << "        languages:" << QString( CALAMARES_TRANSLATION_LANGUAGES ).replace( ";", ", " );
 
-    initSettings();
+    if ( !Calamares::Settings::instance() )
+    {
+        cError() << "Must create Calamares::Settings before the application.";
+        ::exit( 1 );
+    }
     initQmlPath();
     initBranding();
 
@@ -142,35 +146,6 @@ qmlDirCandidates( bool assumeBuilddir )
 }
 
 
-static QStringList
-settingsFileCandidates( bool assumeBuilddir )
-{
-    static const char settings[] = "settings.conf";
-
-    QStringList settingsPaths;
-    if ( CalamaresUtils::isAppDataDirOverridden() )
-    {
-        settingsPaths << CalamaresUtils::appDataDir().absoluteFilePath( settings );
-    }
-    else
-    {
-        if ( assumeBuilddir )
-        {
-            settingsPaths << QDir::current().absoluteFilePath( settings );
-        }
-        if ( CalamaresUtils::haveExtraDirs() )
-            for ( auto s : CalamaresUtils::extraConfigDirs() )
-            {
-                settingsPaths << ( s + settings );
-            }
-        settingsPaths << CMAKE_INSTALL_FULL_SYSCONFDIR "/calamares/settings.conf";  // String concat
-        settingsPaths << CalamaresUtils::appDataDir().absoluteFilePath( settings );
-    }
-
-    return settingsPaths;
-}
-
-
 static QStringList
 brandingFileCandidates( bool assumeBuilddir, const QString& brandingFilename )
 {
@@ -236,49 +211,6 @@ CalamaresApplication::initQmlPath()
 }
 
 
-void
-CalamaresApplication::initSettings()
-{
-    QStringList settingsFileCandidatesByPriority = settingsFileCandidates( isDebug() );
-
-    QFileInfo settingsFile;
-    bool found = false;
-
-    foreach ( const QString& path, settingsFileCandidatesByPriority )
-    {
-        QFileInfo pathFi( path );
-        if ( pathFi.exists() && pathFi.isReadable() )
-        {
-            settingsFile = pathFi;
-            found = true;
-            break;
-        }
-    }
-
-    if ( !found || !settingsFile.exists() || !settingsFile.isReadable() )
-    {
-        cError() << "Cowardly refusing to continue startup without settings."
-                 << Logger::DebugList( settingsFileCandidatesByPriority );
-        if ( CalamaresUtils::isAppDataDirOverridden() )
-        {
-            cError() << "FATAL: explicitly configured application data directory is missing settings.conf";
-        }
-        else
-        {
-            cError() << "FATAL: none of the expected configuration file paths exist.";
-        }
-        ::exit( EXIT_FAILURE );
-    }
-
-    auto* settings = new Calamares::Settings( settingsFile.absoluteFilePath(), isDebug(), this );  // Creates singleton
-    if ( settings->modulesSequence().count() < 1 )
-    {
-        cError() << "FATAL: no sequence set.";
-        ::exit( EXIT_FAILURE );
-    }
-}
-
-
 void
 CalamaresApplication::initBranding()
 {

src/calamares/CalamaresApplication.h

@@ -61,7 +61,6 @@ private slots:
 
 private:
     // Initialization steps happen in this order
-    void initSettings();
     void initQmlPath();
     void initBranding();
     void initModuleManager();

src/calamares/main.cpp

@@ -20,7 +20,7 @@
 
 #include "CalamaresApplication.h"
 
-#include "CalamaresConfig.h"
+#include "Settings.h"
 #include "utils/Dirs.h"
 #include "utils/Logger.h"
 
@@ -83,6 +83,7 @@ handle_args( CalamaresApplication& a )
         CalamaresUtils::setXdgDirs();
     }
 
+    Calamares::Settings::init( parser.isSet( debugOption ) );
     a.init();
 }
 

src/calamares/testmain.cpp

@@ -225,7 +225,7 @@ main( int argc, char* argv[] )
         return 1;
     }
 
-    std::unique_ptr< Calamares::Settings > settings_p( new Calamares::Settings( QString(), true ) );
+    std::unique_ptr< Calamares::Settings > settings_p( Calamares::Settings::init( QString() ) );
     std::unique_ptr< Calamares::JobQueue > jobqueue_p( new Calamares::JobQueue( nullptr ) );
     QMainWindow* mw = nullptr;
 

src/libcalamares/Settings.cpp

@@ -21,6 +21,7 @@
 
 #include "Settings.h"
 
+#include "CalamaresConfig.h"
 #include "utils/Dirs.h"
 #include "utils/Logger.h"
 #include "utils/Yaml.h"
@@ -193,8 +194,8 @@ interpretSequence( const YAML::Node& node, Settings::ModuleSequence& moduleSeque
     }
 }
 
-Settings::Settings( const QString& settingsFilePath, bool debugMode, QObject* parent )
-    : QObject( parent )
+Settings::Settings( const QString& settingsFilePath, bool debugMode )
+    : QObject()
     , m_debug( debugMode )
     , m_doChroot( true )
     , m_promptInstall( false )
@@ -265,4 +266,93 @@ Settings::brandingComponentName() const
     return m_brandingComponentName;
 }
 
+static QStringList
+settingsFileCandidates( bool assumeBuilddir )
+{
+    static const char settings[] = "settings.conf";
+
+    QStringList settingsPaths;
+    if ( CalamaresUtils::isAppDataDirOverridden() )
+    {
+        settingsPaths << CalamaresUtils::appDataDir().absoluteFilePath( settings );
+    }
+    else
+    {
+        if ( assumeBuilddir )
+        {
+            settingsPaths << QDir::current().absoluteFilePath( settings );
+        }
+        if ( CalamaresUtils::haveExtraDirs() )
+            for ( auto s : CalamaresUtils::extraConfigDirs() )
+            {
+                settingsPaths << ( s + settings );
+            }
+        settingsPaths << CMAKE_INSTALL_FULL_SYSCONFDIR "/calamares/settings.conf";  // String concat
+        settingsPaths << CalamaresUtils::appDataDir().absoluteFilePath( settings );
+    }
+
+    return settingsPaths;
+}
+
+Settings*
+Settings::init( bool debugMode )
+{
+    if ( s_instance )
+    {
+        cWarning() << "Calamares::Settings already created";
+        return s_instance;
+    }
+    
+    QStringList settingsFileCandidatesByPriority = settingsFileCandidates( debugMode );
+
+    QFileInfo settingsFile;
+    bool found = false;
+
+    foreach ( const QString& path, settingsFileCandidatesByPriority )
+    {
+        QFileInfo pathFi( path );
+        if ( pathFi.exists() && pathFi.isReadable() )
+        {
+            settingsFile = pathFi;
+            found = true;
+            break;
+        }
+    }
+
+    if ( !found || !settingsFile.exists() || !settingsFile.isReadable() )
+    {
+        cError() << "Cowardly refusing to continue startup without settings."
+                 << Logger::DebugList( settingsFileCandidatesByPriority );
+        if ( CalamaresUtils::isAppDataDirOverridden() )
+        {
+            cError() << "FATAL: explicitly configured application data directory is missing settings.conf";
+        }
+        else
+        {
+            cError() << "FATAL: none of the expected configuration file paths exist.";
+        }
+        ::exit( EXIT_FAILURE );
+    }
+
+    auto* settings = new Calamares::Settings( settingsFile.absoluteFilePath(), debugMode );  // Creates singleton
+    if ( settings->modulesSequence().count() < 1 )
+    {
+        cError() << "FATAL: no sequence set.";
+        ::exit( EXIT_FAILURE );
+    }
+    
+    return settings;
+}
+
+Settings*
+Settings::init( const QString& path )
+{
+    if ( s_instance )
+    {
+        cWarning() << "Calamares::Settings already created";
+        return s_instance;
+    }
+    return new Calamares::Settings( path, true );
+}
+
 }  // namespace Calamares

src/libcalamares/Settings.h

@@ -35,11 +35,14 @@ namespace Calamares
 class DLLEXPORT Settings : public QObject
 {
     Q_OBJECT
+    explicit Settings( const QString& settingsFilePath, bool debugMode );
 public:
-    explicit Settings( const QString& settingsFilePath, bool debugMode, QObject* parent = nullptr );
-
     static Settings* instance();
-
+    /// @brief Find a settings.conf, following @p debugMode
+    static Settings* init( bool debugMode );
+    /// @brief Explicif filename, debug is always true (for testing)
+    static Settings* init( const QString& filename );
+    
     QStringList modulesSearchPaths() const;
 
     using InstanceDescription = QMap< QString, QString >;

src/modules/shellprocess/Tests.cpp

@@ -176,7 +176,7 @@ script:
     if ( !Calamares::JobQueue::instance() )
         (void)new Calamares::JobQueue( nullptr );
     if ( !Calamares::Settings::instance() )
-        (void)new Calamares::Settings( QString(), true );
+        (void)Calamares::Settings::init( QString() );
 
     Calamares::GlobalStorage* gs = Calamares::JobQueue::instance()->globalStorage();
     QVERIFY( gs != nullptr );