The ParseError#to_s implementation was not returning the correct result since it was not using the @msg instance variable to build the error message. However, that ivar is not set in the constructor, nor by the constructor of the superclass, so the error message was always empty.
The
ParseError#to_simplementation was not returning the correct result since it was not using the@msginstance variable to build the error message. However, that ivar is not set in the constructor, nor by the constructor of the superclass, so the error message was always empty.