refactor(core): handle NO_CHANGE in bindingUpdated (#61557)

crisbeto · thePunderWoman · commit 1650a8572a36 · 2025-05-21T15:13:47.000Z
Updates the `bindingUpdated` function to handle `NO_CHANGE` instead of throwing. This will allow us to reuse instructions across more cases. PR Close #61557
diff --git a/packages/core/src/render3/bindings.ts b/packages/core/src/render3/bindings.ts
@@ -42,9 +42,13 @@ export function getBinding(lView: LView, bindingIndex: number): any {
  *          `CheckNoChangesMode`)
  */
 export function bindingUpdated(lView: LView, bindingIndex: number, value: any): boolean {
-  ngDevMode && assertNotSame(value, NO_CHANGE, 'Incoming value should never be NO_CHANGE.');
   ngDevMode &&
     assertLessThan(bindingIndex, lView.length, `Slot should have been initialized to NO_CHANGE`);
+
+  if (value === NO_CHANGE) {
+    return false;
+  }
+
   const oldValue = lView[bindingIndex];
 
   if (Object.is(oldValue, value)) {
diff --git a/packages/core/src/render3/instructions/attribute.ts b/packages/core/src/render3/instructions/attribute.ts
@@ -8,7 +8,6 @@
 import {bindingUpdated} from '../bindings';
 import {SanitizerFn} from '../interfaces/sanitization';
 import {getLView, getSelectedTNode, getTView, nextBindingIndex} from '../state';
-import {NO_CHANGE} from '../tokens';
 import {elementAttributeInternal, storePropertyBindingMetadata} from './shared';
 
 /**
@@ -30,17 +29,13 @@ export function ɵɵattribute(
   sanitizer?: SanitizerFn | null,
   namespace?: string,
 ): typeof ɵɵattribute {
+  const lView = getLView();
   const bindingIndex = nextBindingIndex();
-
-  // Value can be `NO_CHANGE` in case of an interpolation.
-  if (value !== NO_CHANGE) {
-    const lView = getLView();
-    if (bindingUpdated(lView, bindingIndex, value)) {
-      const tView = getTView();
-      const tNode = getSelectedTNode();
-      elementAttributeInternal(tNode, lView, name, value, sanitizer, namespace);
-      ngDevMode && storePropertyBindingMetadata(tView.data, tNode, 'attr.' + name, bindingIndex);
-    }
+  if (bindingUpdated(lView, bindingIndex, value)) {
+    const tView = getTView();
+    const tNode = getSelectedTNode();
+    elementAttributeInternal(tNode, lView, name, value, sanitizer, namespace);
+    ngDevMode && storePropertyBindingMetadata(tView.data, tNode, 'attr.' + name, bindingIndex);
   }
 
   return ɵɵattribute;
