migration: use thunks

Otherwise we get QCoreApplication used before
QApplication instance is created.

Requesting the sorted migration data will force the
thunks.

2 files changed, 94 insertions, 69 deletions

diff --git a/migration/migration.cpp b/migration/migration.cpp
index b92d6384..569dff99 100644
--- a/migration/migration.cpp
+++ b/migration/migration.cpp
@@ -26,11 +26,14 @@ namespace migrations {
 
 namespace detail {
 
-void migrator::register_migration(migration* m)
+static std::vector<mptr> migration_list;
+static std::vector<mfun> migration_thunks;
+
+void migrator::register_migration(mptr m)
 {
     const QString date = m->unique_date();
 
-    for (migration* m2 : migrations())
+    for (mptr m2 : migration_list)
         if (m2->unique_date() == date)
             std::abort();
 
@@ -64,13 +67,38 @@ void migrator::register_migration(migration* m)
     if (day_ < 1 || day_ > 31)
         abort();
 
-    migrations().push_back(m);
+    migration_list.push_back(m);
 }
 
-std::vector<migration*>& migrator::migrations()
+void migrator::eval_thunks()
 {
-    static std::vector<migration*> ret;
-    return ret;
+    for (auto& fun : migration_thunks)
+    {
+        mptr m = fun();
+        register_migration(m);
+    }
+    if (migration_thunks.size())
+        sort_migrations();
+    migration_thunks.clear();
+}
+
+void migrator::add_migration_thunk(mfun& thunk)
+{
+    migration_thunks.push_back(thunk);
+}
+
+std::vector<mptr>& migrator::migrations()
+{
+    eval_thunks();
+    return migration_list;
+}
+
+void migrator::sort_migrations()
+{
+    std::sort(migration_list.begin(), migration_list.end(),
+              [](const mptr x, const mptr y) {
+        return x->unique_date() < y->unique_date();
+    });
 }
 
 QString migrator::last_migration_time()
@@ -88,7 +116,7 @@ QString migrator::last_migration_time()
 
 QString migrator::time_after_migrations()
 {
-    const std::vector<migration*> list = sorted_migrations();
+    const std::vector<mptr>& list = migrations();
 
     if (list.size() == 0u)
         return QStringLiteral("19700101_00");
@@ -113,16 +141,6 @@ void migrator::set_last_migration_time(const QString& val)
     });
 }
 
-std::vector<migration*> migrator::sorted_migrations()
-{
-    std::vector<migration*> list(migrations());
-
-    using mm = migration*;
-
-    std::sort(list.begin(), list.end(), [](const mm x, const mm y) { return x->unique_date() < y->unique_date(); });
-    return list;
-}
-
 int migrator::to_int(const QString& str, bool& ok)
 {
     bool tmp = false;
@@ -133,46 +151,37 @@ int migrator::to_int(const QString& str, bool& ok)
 
 std::vector<QString> migrator::run()
 {
-    std::vector<migration*> migrations = sorted_migrations();
     std::vector<QString> done;
 
     const QString last_migration = last_migration_time();
 
-    for (migration* m_ : migrations)
-    {
-        migration& m(*m_);
-
-        const QString date = m.unique_date();
-
-        if (date <= last_migration)
-            continue;
-
-        if (m.should_run())
-        {
-            m.run();
-            done.push_back(m.name());
-        }
-    }
-
-    mark_config_as_not_needing_migration();
-
-    if (done.size())
-    {
-        for (const QString& name : done)
-        {
-            const QByteArray data = name.toUtf8();
-            qDebug() << "migrate:" << data.constData();
-        }
-    }
+    options::group::with_global_settings_object([&](QSettings&) {
+        options::group::with_settings_object([&](QSettings&) {
+            for (mptr m : migrations())
+            {
+                const QString date = m->unique_date();
+
+                if (date <= last_migration)
+                    continue;
+
+                if (m->should_run())
+                {
+                    const QByteArray name = m->name().toUtf8();
+                    const QByteArray date = m->unique_date().toUtf8();
+                    qDebug() << "migrate:" << date.constData() << name.constData();
+                    m->run();
+                    done.push_back(m->name());
+                }
+            }
+            mark_config_as_not_needing_migration();
+        });
+    });
 
     return done;
 }
 
 }
 
-migration::migration() {}
-migration::~migration() {}
-
 } // ns
 
 std::vector<QString> run_migrations()
diff --git a/migration/migration.hpp b/migration/migration.hpp
index 5f99de7a..e81e0ae5 100644
--- a/migration/migration.hpp
+++ b/migration/migration.hpp
@@ -13,25 +13,36 @@
 
 #include "export.hpp"
 
+#include <functional>
+
 namespace migrations {
 
-class migration;
+struct migration;
 class registrator;
 
 namespace detail {
-    class migrator final
+    using mptr = std::shared_ptr<migration>;
+    using mfun = std::function<mptr ()>;
+
+    struct migrator
     {
-        static std::vector<migration*>& migrations();
+        static std::vector<QString> run();
+        static void add_migration_thunk(std::function<mptr()>& thunk);
+        static void mark_config_as_not_needing_migration();
+
+    private:
+        static void sort_migrations();
+
+        static void register_migration(mptr m);
+        static std::vector<mptr>& migrations();
+
+        static void eval_thunks();
+
         static QString last_migration_time();
         static QString time_after_migrations();
+
         static void set_last_migration_time(const QString& val);
-        migrator() = delete;
-        static std::vector<migration*> sorted_migrations();
         static int to_int(const QString& str, bool& ok);
-    public:
-        static std::vector<QString> run();
-        static void register_migration(migration* m);
-        static void mark_config_as_not_needing_migration();
     };
 
     template<typename t>
@@ -39,8 +50,9 @@ namespace detail {
     {
         registrator()
         {
-            static t m;
-            migrator::register_migration(static_cast<migration*>(&m));
+            mfun f { []() { return std::shared_ptr<migration>(new t); } };
+
+            migrator::add_migration_thunk(f);
         }
     };
 }
@@ -49,29 +61,33 @@ namespace detail {
 #   error "oops, need __COUNTER__ extension for preprocessor"
 #endif
 
-#define OPENTRACK_MIGRATION(type) static ::migrations::detail::registrator<type> opentrack_migration_registrator__ ## __COUNTER__ ## _gensym
+#define MIGRATE_EXPAND2(x) x
+#define MIGRATE_EXPAND1(x) MIGRATE_EXPAND2(x)
+#define MIGRATE_EXPANDED2(type, ctr) \
+    static ::migrations::detail::registrator<type> opentrack_migration_registrator_ ## ctr
+#define MIGRATE_EXPANDED1(type, ctr) \
+    MIGRATE_EXPANDED2(type, ctr)
+
+#define OPENTRACK_MIGRATION(type) \
+    MIGRATE_EXPANDED1(type, MIGRATE_EXPAND1(__COUNTER__))
 
 #ifdef Q_CREATOR_RUN
 #   pragma clang diagnostic ignored "-Wweak-vtables"
 #endif
 
-class migration
+struct migration
 {
-    migration& operator=(const migration&) = delete;
-    migration(const migration&) = delete;
-    migration& operator=(migration&&) = delete;
-    migration(migration&&) = delete;
-
-public:
-    migration();
-    virtual ~migration();
+    migration() = default;
+    inline virtual ~migration();
     virtual QString unique_date() const = 0;
     virtual QString name() const = 0;
     virtual bool should_run() const = 0;
     virtual void run() = 0;
 };
 
-}
+inline migration::~migration() {}
+
+} // ns migrations
 
 OTR_MIGRATION_EXPORT std::vector<QString> run_migrations();
 OTR_MIGRATION_EXPORT void mark_config_as_not_needing_migration();