Original itemspec is returned when:
- illegal filespec contains
- both wildcards and escaped wildcards (
%2a,%3f) - illegal file chars
...- a
:anywhere but the second character - a
..after a wildcard - a path fragment which contains
**and other characters (e.g./**f/)
- both wildcards and escaped wildcards (
- Any IO related exception is thrown during file walking: https://github.com/dotnet/msbuild/blob/c1d949558b4808ca9381d09af384b66b31cde2b2/src/Shared/ExceptionHandling.cs#L125-L140
- System.UnauthorizedAccessException and System.Security.SecurityException from directory enumeration (Directory.EnumerateFileSystemEntries) are ignored, and the files / directories which cause it are excluded from the results.