When dumping default values in ReflectionXXX::__toString(), for
expression initializers print the AST export instead of trying to
evaluate the expression. With the introduction of "new in
initializers" the result of the evaluation will commonly not be
printable at all, and "__toString" will throw an exception, which
is not particularly useful. Using the AST export also provides more
information on how the parameter was originally declared, e.g. it
preserves the fact that a certain constant was used.
Closes GH-7540.
RFC: https://wiki.php.net/rfc/tostring_exceptions
And convert some object to string conversion related recoverable
fatal errors into Error exceptions.
Improve exception safety of internal code performing string
conversions.
Access to undefined constants will now always result in an Error
exception being thrown.
This required quite a few test changes, because there were many
buggy tests that unintentionally used bareword fallback in combination
with error suppression.