Don't create a transaction for every revision that we don't replay.

This had a significant performance impact when i.e. syncing a folder
with 10k messages.

1 files changed, 12 insertions, 4 deletions

diff --git a/common/sourcewriteback.cpp b/common/sourcewriteback.cpp
index 7d21ea6..fe996cb 100644
--- a/common/sourcewriteback.cpp
+++ b/common/sourcewriteback.cpp
@@ -55,18 +55,26 @@ RemoteIdMap &SourceWriteBack::syncStore()
     return *mSyncStore;
 }
 
-KAsync::Job<void> SourceWriteBack::replay(const QByteArray &type, const QByteArray &key, const QByteArray &value)
+bool SourceWriteBack::canReplay(const QByteArray &type, const QByteArray &key, const QByteArray &value)
 {
-    SinkTrace() << "Replaying" << type << key;
-
     Sink::EntityBuffer buffer(value);
     const Sink::Entity &entity = buffer.entity();
     const auto metadataBuffer = Sink::EntityBuffer::readBuffer<Sink::Metadata>(entity.metadata());
     Q_ASSERT(metadataBuffer);
     if (!metadataBuffer->replayToSource()) {
         SinkTrace() << "Change is coming from the source";
-        return KAsync::null<void>();
     }
+    return metadataBuffer->replayToSource();
+}
+
+KAsync::Job<void> SourceWriteBack::replay(const QByteArray &type, const QByteArray &key, const QByteArray &value)
+{
+    SinkTrace() << "Replaying" << type << key;
+
+    Sink::EntityBuffer buffer(value);
+    const Sink::Entity &entity = buffer.entity();
+    const auto metadataBuffer = Sink::EntityBuffer::readBuffer<Sink::Metadata>(entity.metadata());
+    Q_ASSERT(metadataBuffer);
     Q_ASSERT(!mSyncStore);
     Q_ASSERT(!mEntityStore);
     Q_ASSERT(!mTransaction);