It's possible to return a reference from __toString(), but this is not
handled and results in a (confusing) error telling that the return value
must be a string.
Properly handle this by unwrapping the reference.
Closes GH-18810.
- Property hooks may now throw exceptions, that seem to be forgotten to be handled by https://github.com/php/php-src/pull/18442
- The $previous and $trace properties are private, and they were not accessible from the constructor of a child class
Add directories for tests relating to
- halting the compiler
- `declare()` usage
- exception handlers
- `get_class_methods()`
- `get_class_vars()`
- `isset()`
- name collisions
As well as organizing a couple of tests into existing sub directories along the
way
Work towards GH-15631
Create new sub directories for tests related to backtraces and for tests
related to `$this` being reserved in different places and not being usable or
reassignable.
Work towards GH-15631
Second pass through `Zend/tests/bug*` to organize the tests.
Move tests to existing sub directories, and create some new sub directories:
* `ArrayAccess`
* `autoload`
* `clone`
* `serialize` (also covers `unserialize()`)
* `switch`
Work towards GH-15631
Move more low-hanging fruit, creating new directories for the tests for:
* comparisons
* dynamic calls
* error messages
* `error_reporting()`
* exceptions
* `foreach()`
* garbage collection
* group `use` statements
* heredoc and nowdoc
* `goto` jumps
* late static binding
* magic methods
* namespaces
* numeric literal separators
* objects
* `settype()`
* cleaning of temporary values
* `unset()`
Additionally, move some tests into the existing subdirectory for `list()`
tests.
Drive-by fixes of some test numbers in the names of the `goto` tests.
Work towards GH-15631
