public Task <BuildResult> Clean(ProgressMonitor monitor, ConfigurationSelector configuration, OperationContext operationContext = null) { var slnConf = ParentSolution?.GetConfiguration(configuration); if (slnConf == null) { return(Task.FromResult(new BuildResult())); } //don't collect dependencies, CleanItems will do it var collected = new HashSet <SolutionItem> (); CollectBuildableEntries(collected, configuration, slnConf, false); return(ParentSolution.CleanItems( monitor, configuration, collected, operationContext, IsRoot ? GettextCatalog.GetString("Cleaning solution {0} ({1})", Name, configuration.ToString()) : null )); }