public void TestPreventsDoubleAdd()
{
var index = new FileIndex();
var testFileInfo = FileSystemTestingHelpers.CreateFileInfo("/dir/foo.txt");
index.Add(testFileInfo);
Assert.IsNotNull(index.GetFileInfo(testFileInfo.Path));
// Attempt to re-add the same file. Should throw.
Assert.ThrowsException <AegisInternalErrorException>(() => index.Add(testFileInfo));
// Remove the file, then add it back. Should not throw.
index.Remove(testFileInfo.Path);
index.Add(testFileInfo);
// Attempt to add another file with the same virtual path. Should throw.
var fileInfoSamePath = FileSystemTestingHelpers.CreateFileInfo(testFileInfo.Path.ToString());
Assert.ThrowsException <AegisInternalErrorException>(() => index.Add(fileInfoSamePath));
// Attempt to add another file with the same ID, different virtual path. Should throw.
var fileInfoSameId = FileSystemTestingHelpers.CreateFileInfo("/dir/bar.txt", testFileInfo.FileId);
Assert.ThrowsException <AegisInternalErrorException>(() => index.Add(fileInfoSameId));
}