Issue #3383449 by catch, Wim Leers, Kingdutch: Add Fibers support to Drupal\Core\Render\Renderer (d41f1a01) · Commits · project / drupal

core/lib/Drupal/Core/Render/Renderer.php

+74 −9

Original line number	Diff line number	Diff line
		@@ -162,22 +162,43 @@ public function renderPlain(&$elements) {
		}

		/**
		* {@inheritdoc}
		* Renders a placeholder into markup.
		*
		* @param array $placeholder_element
		* The placeholder element by reference.
		*
		* @return \Drupal\Component\Render\MarkupInterface\|string
		* The rendered HTML.
		*/
		public function renderPlaceholder($placeholder, array $elements) {
		// Get the render array for the given placeholder
		$placeholder_elements = $elements['#attached']['placeholders'][$placeholder];

		protected function doRenderPlaceholder(array &$placeholder_element): MarkupInterface\|string {
		// Prevent the render array from being auto-placeholdered again.
		$placeholder_elements['#create_placeholder'] = FALSE;
		$placeholder_element['#create_placeholder'] = FALSE;

		// Render the placeholder into markup.
		$markup = $this->renderPlain($placeholder_elements);
		$markup = $this->renderPlain($placeholder_element);
		return $markup;
		}

		/**
		* Replaces a placeholder with its markup.
		*
		* @param string $placeholder
		* The placeholder HTML.
		* @param \Drupal\Component\Render\MarkupInterface\|string $markup
		* The markup to replace the placeholder with.
		* @param array $elements
		* The render array that the placeholder is from.
		* @param array $placeholder_element
		* The placeholder element render array.
		*
		* @return \Drupal\Component\Render\MarkupInterface\|string
		* The rendered HTML.
		*/
		protected function doReplacePlaceholder(string $placeholder, string\|MarkupInterface $markup, array $elements, array $placeholder_element): array {
		// Replace the placeholder with its rendered markup, and merge its
		// bubbleable metadata with the main elements'.
		$elements['#markup'] = Markup::create(str_replace($placeholder, $markup, $elements['#markup']));
		$elements = $this->mergeBubbleableMetadata($elements, $placeholder_elements);
		$elements = $this->mergeBubbleableMetadata($elements, $placeholder_element);

		// Remove the placeholder that we've just rendered.
		unset($elements['#attached']['placeholders'][$placeholder]);
		@@ -185,6 +206,16 @@ public function renderPlaceholder($placeholder, array $elements) {
		return $elements;
		}

		/**
		* {@inheritdoc}
		*/
		public function renderPlaceholder($placeholder, array $elements) {
		// Get the render array for the given placeholder
		$placeholder_element = $elements['#attached']['placeholders'][$placeholder];
		$markup = $this->doRenderPlaceholder($placeholder_element);
		return $this->doReplacePlaceholder($placeholder, $markup, $elements, $placeholder_element);
		}

		/**
		* {@inheritdoc}
		*/
		@@ -665,13 +696,47 @@ protected function replacePlaceholders(array &$elements) {

		// First render all placeholders except 'status messages' placeholders.
		$message_placeholders = [];
		$fibers = [];
		foreach ($elements['#attached']['placeholders'] as $placeholder => $placeholder_element) {
		if (isset($placeholder_element['#lazy_builder']) && $placeholder_element['#lazy_builder'][0] === 'Drupal\Core\Render\Element\StatusMessages::renderMessages') {
		$message_placeholders[] = $placeholder;
		}
		else {
		$elements = $this->renderPlaceholder($placeholder, $elements);
		// Get the render array for the given placeholder
		$fibers[$placeholder] = new \Fiber(function () use ($placeholder_element) {
		return [$this->doRenderPlaceholder($placeholder_element), $placeholder_element];
		});
		}
		}
		while (count($fibers) > 0) {
		$iterations = 0;
		foreach ($fibers as $placeholder => $fiber) {
		if (!$fiber->isStarted()) {
		$fiber->start();
		}
		elseif ($fiber->isSuspended()) {
		$fiber->resume();
		}
		// If the Fiber hasn't terminated by this point, move onto the next
		// placeholder, we'll resume this fiber again when we get back here.
		if (!$fiber->isTerminated()) {
		// If we've gone through the placeholders once already, and they're
		// still not finished, then start to allow code higher up the stack to
		// get on with something else.
		if ($iterations) {
		$fiber = \Fiber::getCurrent();
		if ($fiber !== NULL) {
		$fiber->suspend();
		}
		}
		continue;
		}
		[$markup, $placeholder_element] = $fiber->getReturn();

		$elements = $this->doReplacePlaceholder($placeholder, $markup, $elements, $placeholder_element);
		unset($fibers[$placeholder]);
		}
		$iterations++;
		}

		// Then render 'status messages' placeholders.

core/tests/Drupal/Tests/Core/Render/RendererTestBase.php

+5 −0

Original line number	Diff line number	Diff line
		@@ -314,6 +314,11 @@ public static function callback($animal, $use_animal_as_array_key = FALSE) {
		* A renderable array.
		*/
		public static function callbackPerUser($animal) {
		// As well as adding the user cache context, additionally suspend the
		// current Fiber if there is one.
		if ($fiber = \Fiber::getCurrent()) {
		$fiber->suspend();
		}
		$build = static::callback($animal);
		$build['#cache']['contexts'][] = 'user';
		return $build;