fails:Ruby character strings taints the result of interpolation when an interpolated value is tainted
fails:Ruby character strings untrusts the result of interpolation when an interpolated value is untrusted
fails:Ruby character strings call #to_s when the object is not a String
fails:Ruby character strings call #to_s as a private method
fails:Ruby character strings Unicode escaping can be done with \u{} and one to six hex digits
fails:Ruby character strings Unicode escaping can be done with \u and four hex digits
fails:Ruby character strings Unicode escaping with US-ASCII source encoding produces a UTF-8-encoded string when escaping non-ASCII characters via \u
fails:Ruby character strings Unicode escaping with US-ASCII source encoding produces a UTF-8-encoded string when escaping non-ASCII characters via \u{}
fails:Ruby String interpolation creates a String having an Encoding compatible with all components
fails:Ruby String interpolation creates a String having the Encoding of the components when all are the same Encoding
fails:Ruby String interpolation raises an Encoding::CompatibilityError if the Encodings are not compatible
fails:Ruby character strings uses an internal representation when #to_s doesn't return a String
fails:Ruby character strings calls #to_s as a private method
