path.toUri preserves trailing slashes for relative paths.Context.relative - don't call current if from is not relative.context field that provides access to a Context object for the current system.Many members on Style that provided access to patterns and functions used internally for parsing paths have been deprecated.
Manually parse paths (rather than using RegExps to do so) for better performance.
path.prettyUri, which produces a human-readable representation of a URI.path.fromUri now accepts strings as well as Uri objects.