Merge pull request #8148 from QwikDev/computed-only-fire-when-changed

perf: computed signals only trigger when changed

Author: wmertens

.changeset/loud-cars-run.md

@@ -0,0 +1,5 @@
+---
+'@builder.io/qwik': minor
+---
+
+PERF: Computed signals now only trigger listeners if their value has changed

packages/qwik/src/core/use/use-task.ts

@@ -750,8 +750,10 @@ export const runComputed = (
     untrack(() => {
       const signal = task.$state$! as SignalInternal<unknown>;
       signal[QObjectSignalFlags] &= ~SIGNAL_UNASSIGNED;
-      signal.untrackedValue = returnValue;
-      signal[QObjectManagerSymbol].$notifySubs$();
+      if (signal.untrackedValue !== returnValue) {
+        signal.untrackedValue = returnValue;
+        signal[QObjectManagerSymbol].$notifySubs$();
+      }
     });
   };
   const fail = (reason: unknown) => {

packages/qwik/src/server/preload-impl.ts

@@ -66,7 +66,7 @@ export const preloaderPre = (
        * We add modulepreloads even when the script is at the top because they already fire during
        * html download
        */
-      jsx('link', { rel: 'modulepreload', href: preloaderPath, nonce }),
+      jsx('link', { rel: 'modulepreload', href: preloaderPath, nonce, crossorigin: 'anonymous' }),
       jsx('link', {
         rel: 'preload',
         href: bundleGraphPath,