fixing a bug where streams were removed from playlist during Clementine's startup

src/core/player.cpp

@@ -154,7 +154,7 @@ void Player::TrackEnded() {
   }
 
   if (current_item_ && current_item_->IsLocalLibraryItem() &&
-      !playlists_->active()->has_scrobbled()) {
+      current_item_->Metadata().id() != -1 && !playlists_->active()->has_scrobbled()) {
     // The track finished before its scrobble point (30 seconds), so increment
     // the play count now.
     playlists_->library_backend()->IncrementPlayCountAsync(

src/library/libraryplaylistitem.h

@@ -34,7 +34,7 @@ class LibraryPlaylistItem : public PlaylistItem {
 
   QUrl Url() const;
 
-  bool IsLocalLibraryItem() const { return song_.id() != -1; }
+  bool IsLocalLibraryItem() const { return true; }
 
  protected:
   QVariant DatabaseValue(DatabaseColumn column) const;

src/playlist/playlist.cpp

@@ -235,7 +235,8 @@ QVariant Playlist::data(const QModelIndex& index, int role) const {
 
     case Role_CanSetRating:
       return index.column() == Column_Rating &&
-             items_[index.row()]->IsLocalLibraryItem();
+             items_[index.row()]->IsLocalLibraryItem() &&
+             items_[index.row()]->Metadata().id() != -1;
 
     case Qt::EditRole:
     case Qt::ToolTipRole:
@@ -1130,11 +1131,13 @@ void Playlist::ItemsLoaded() {
 
   PlaylistItemList items = watcher->future().results();
 
-  // backend returns empty elements for items which it couldn't 
+  // backend returns empty elements for library items which it couldn't 
   // match (because they got deleted); we don't need those
   QMutableListIterator<PlaylistItemPtr> it(items);
   while (it.hasNext()) {
-    if (it.next()->Metadata().filename().isEmpty()) {
+    PlaylistItemPtr item = it.next();
+
+    if (item->IsLocalLibraryItem() && item->Metadata().filename().isEmpty()) {
       it.remove();
     }
   }
@@ -1402,7 +1405,7 @@ void Playlist::RateSong(const QModelIndex& index, double rating) {
 
   if(has_item_at(row)) {
     PlaylistItemPtr item = item_at(row);
-    if (item && item->IsLocalLibraryItem()) {
+    if (item && item->IsLocalLibraryItem() && item->Metadata().id() != -1) {
       library_->UpdateSongRatingAsync(item->Metadata().id(), rating);
     }
   }

src/playlist/playlistitem.h

@@ -130,6 +130,9 @@ class PlaylistItem : public boost::enable_shared_from_this<PlaylistItem> {
 
   // Convenience function to find out whether this item is from the local
   // library, as opposed to a device, a file on disk, or a stream.
+  // Remember that even if this returns true, the library item might be
+  // invalid so you might want to check that it's id is not equal to -1
+  // before actually using it.
   virtual bool IsLocalLibraryItem() const { return false; }
 
  protected:

src/scripting/python/playlistitem.sip

@@ -177,8 +177,11 @@ Returns true if L{SetTemporaryMetadata()} has been called.
   bool IsLocalLibraryItem() const;
 %Docstring
 IsLocalLibraryItem() -> bool
-Convenience function to check whether this item is from the local library (the
-list of songs appearing in the Library tab).
+Convenience function to check whether this item is from the local
+library, as opposed to a device, a file on disk or a stream.
+Remember that even if this returns true, the library item might be
+invalid so you might want to check that it's id is not equal to -1
+before actually using it.
 %End
 
   void SetBackgroundColor(short priority, const QColor& color);

src/ui/mainwindow.cpp

@@ -847,7 +847,8 @@ void MainWindow::SongChanged(const Song& song) {
 void MainWindow::TrackSkipped(PlaylistItemPtr item) {
   // If it was a library item then we have to increment its skipped count in
   // the database.
-  if (item && item->IsLocalLibraryItem() && !playlists_->active()->has_scrobbled()) {
+  if (item && item->IsLocalLibraryItem() &&
+      item->Metadata().id() != -1 && !playlists_->active()->has_scrobbled()) {
     Song song = item->Metadata();
     const qint64 position = player_->engine()->position_nanosec();
     const qint64 length = player_->engine()->length_nanosec();
@@ -989,7 +990,7 @@ void MainWindow::UpdateTrackPosition() {
     playlists_->active()->set_scrobbled(true);
 
     // Update the play count for the song if it's from the library
-    if (item->IsLocalLibraryItem()) {
+    if (item->IsLocalLibraryItem() && item->Metadata().id() != -1) {
       library_->backend()->IncrementPlayCountAsync(item->Metadata().id());
     }
   }
@@ -1191,7 +1192,8 @@ void MainWindow::PlaylistRightClick(const QPoint& global_pos, const QModelIndex&
     ui_->action_edit_value->setText(tr("Edit tag \"%1\"...").arg(column_name));
 
     // Is it a library item?
-    if (playlists_->current()->item_at(source_index.row())->IsLocalLibraryItem()) {
+    PlaylistItemPtr item = playlists_->current()->item_at(source_index.row());
+    if (item->IsLocalLibraryItem() && item->Metadata().id() != -1) {
       playlist_organise_->setVisible(editable);
     } else {
       playlist_copy_to_library_->setVisible(editable);