Revert "Revert preact signals support (#4843)" (#5015)

This reverts commit 25a5b9a89aee81c87affca64e1682ebc0c553eaf.

1 files changed, 24 insertions, 0 deletions

diff --git a/packages/integrations/preact/src/static-html.ts b/packages/integrations/preact/src/static-html.ts
new file mode 100644
index 000000000..e1127d226
--- /dev/null
+++ b/packages/integrations/preact/src/static-html.ts
@@ -0,0 +1,24 @@
+import { h } from 'preact';
+
+/**
+ * Astro passes `children` as a string of HTML, so we need
+ * a wrapper `div` to render that content as VNodes.
+ *
+ * As a bonus, we can signal to Preact that this subtree is
+ * entirely static and will never change via `shouldComponentUpdate`.
+ */
+const StaticHtml = ({ value, name }: { value: string; name?: string }) => {
+	if (!value) return null;
+	return h('astro-slot', { name, dangerouslySetInnerHTML: { __html: value } });
+};
+
+/**
+ * This tells Preact to opt-out of re-rendering this subtree,
+ * In addition to being a performance optimization,
+ * this also allows other frameworks to attach to `children`.
+ *
+ * See https://preactjs.com/guide/v8/external-dom-mutations
+ */
+StaticHtml.shouldComponentUpdate = () => false;
+
+export default StaticHtml;