Compile SCSS added through AssetCollector

[ww-ysg]

Compile SCSS added through AssetCollector

Is your feature request related to a problem? Please describe

In TYPO3 Version 10 the AssetCollector was introduced. It offers an easy way to include JavaScript and CSS Files. It would be great if SCSS Files included by the AssetCollector will be compiled just like SCSS Files included in TypoScript right now.

Describe the solution you'd like

With the AssetCollector the Event BeforeStylesheetsRenderingEvent was introduced, which could be used to compile the SCSS File. A possible Implementation could look like this:

public function __invoke(
        BeforeStylesheetsRenderingEvent $event,
    ): void {
        if(ApplicationType::fromRequest($GLOBALS['TYPO3_REQUEST'])->isFrontend()) {
            $assetCollector = $event->getAssetCollector();
            $stylesheets = $assetCollector->getStyleSheets();
            foreach ($stylesheets as $identifier => $stylesheet) {
                if(isset($stylesheet['source'])) {
                    if(str_contains($stylesheet['source'], 'EXT:')) {
                        $compiledFile = $this->compileService->getCompiledFile($GLOBALS['TYPO3_REQUEST'], $stylesheet['source']);
                        if($compiledFile) {
                            $assetCollector->addStyleSheet($identifier, $compiledFile);
                        }
                    }
                }
            }
        }
    }