Important: #82763 - Fluid config for ExpressionNodeType and TemplatePreProcessor made global

See Issue #82763

Description

Before, Fluid's arrays of class names for ExpressionNodeType and TemplatePreProcessor were hardcoded into the RenderingContext constructor and were not possible to modify except when having access to the RenderingContext.

Now, these two arrays of class names are possible to configure in TYPO3_CONF_VARS which allows extensions or site administrators to add and remove such Fluid components on a global level.

Example:

// Add one new ExpressionNodeType and one new TemplatePreProcessor to be used in every RenderingContext
// For example from an ext_localconf.php file in an extension.
$GLOBALS['TYPO3_CONF_VARS']['SYS']['fluid']['expressionNodeTypes'][] = \MyVendor\MyExtension\MyFluidExpressionNodeType::class;
$GLOBALS['TYPO3_CONF_VARS']['SYS']['fluid']['preProcessors'][] = \MyVendor\MyExtension\MyFluidTemplatePreProcessor::class;

These classes will then be added to the list of existing implementations and will be automatically used as defaults when new RenderingContext instances are created.

See for reference how to create such implementations:

  • \TYPO3Fluid\Fluid\Core\Parser\TemplateProcessorInterface
  • \TYPO3Fluid\Fluid\Core\Parser\SyntaxTree\Expression\ExpressionNodeInterface

Both interfaces contain the documentation for how they must be implemented, when/why functions get called and what the expected return types are. The interfaces must of course be implemented by classes you add to TYPO3_CONF_VARS in these configuration sections. Due to their global nature you should be very careful to implement the classes and in particular observe the return types.