protected override ImmutableArray <NamespaceOrTypeAndUsingDirective> GetConsolidatedUsings()
{
var currentSubmissionUsings = this.Compilation.GetSubmissionImports().Usings;
// find the first preceding non-empty submission (has InteractiveUsingsBinder):
CSharpCompilation previous = this.Compilation.PreviousSubmission;
InteractiveUsingsBinder previousBinder = null;
while (previous != null && previousBinder == null)
{
previousBinder = previous.GetInteractiveUsingsBinder();
previous = previous.PreviousSubmission;
}
if (previousBinder != null)
{
// TODO (tomat):
// optimization: do this only if additional references are added to the submission:
return(RebindAndAddUsings(previousBinder.ConsolidatedUsings, currentSubmissionUsings));
}
return(currentSubmissionUsings);
}