public FileSystemSnapshot Compute(IFileSystemNameFactory fileNameFactory,
FileSystemSnapshot oldSnapshot,
FullPathChanges pathChanges /* may be null */,
IList <IProject> projects,
int version,
CancellationToken cancellationToken)
{
cancellationToken.ThrowIfCancellationRequested(); // cancellation
using (var progress = _progressTrackerFactory.CreateIndeterminateTracker()) {
// Clear file name factory intern tables if no projects. We could be
// more aggressive at the expense of decreasing string interning.
if (projects.Count == 0)
{
fileNameFactory.ClearInternedStrings();
}
var projectRoots =
projects
.Distinct(new ProjectPathComparer())
.Select(project => {
cancellationToken.ThrowIfCancellationRequested(); // cancellation
var projectSnapshotBuilder = new ProjectRootSnapshotBuilder(
_fileSystem, fileNameFactory, oldSnapshot, project, progress,
(pathChanges == null ? null : new ProjectPathChanges(project.RootPath, pathChanges.Entries)),
cancellationToken);
var rootSnapshot = projectSnapshotBuilder.Build();
return(new ProjectRootSnapshot(project, rootSnapshot));
})
.OrderBy(projectRoot => projectRoot.Directory.DirectoryName)
.ToReadOnlyCollection();
return(new FileSystemSnapshot(version, projectRoots));
}
}
