Code Modernization: Fix trigger_error() with E_USER_ERROR deprecation in Text_Diff::_check().
PHP 8.4 deprecates the use of trigger_errror() with E_USER_ERROR as the error level, as there are a number of gotchas to this way of creating a Fatal Error (finally blocks not executing, destructors not executing). The recommended replacements are either to use exceptions or to do a hard exit.
This is an unmaintained external dependency; thus, the fix is made in the WP specific copy of the dependency.
Now, there were basically three options:
- Silence the deprecation until PHP 9.0 and delay properly solving this until then.
This would lead to an awkward solution, as prior to PHP 8.0, error silencing would apply to all errors, while, as of PHP 8.0, it will no longer apply to fatal errors.
It also would only buy us some time and wouldn't actually solve anything.
This would make the code untestable and would disable handling of these errors via custom error handlers, which makes this an undesirable solution.
This makes for the most elegant solution with the least BC-breaking impact.
The third option is implemented which:
- Introduces a new
Text_Exception class.
- Starts using that in the
Text_Diff::_check() method in all applicable places.
- Adds tests for the first two error conditions.
References:
Follow-up to [59070], [52978], [7747].
Props jrf.
See #62061.