refactor(ivy): remove dynamicViewCount from LContainer (#23963)

PR Close #23963

packages/core/src/render3/di.ts

@@ -572,7 +572,7 @@ export function getOrCreateContainerRef(di: LInjector): viewEngine_ViewContainer
 
     ngDevMode && assertNodeOfPossibleTypes(vcRefHost, TNodeType.Container, TNodeType.Element);
     const hostParent = getParentLNode(vcRefHost) !;
-    const lContainer = createLContainer(hostParent, vcRefHost.view);
+    const lContainer = createLContainer(hostParent, vcRefHost.view, undefined, true);
     const lContainerNode: LContainerNode = createLNodeObject(
         TNodeType.Container, vcRefHost.view, hostParent, undefined, lContainer, null);
 
@@ -644,19 +644,6 @@ class ViewContainerRef implements viewEngine_ViewContainerRef {
 
     this._viewRefs.splice(adjustedIdx, 0, viewRef);
 
-    // If the view is dynamic (has a template), it needs to be counted both at the container
-    // level and at the node above the container.
-    if (lViewNode.data.template !== null) {
-      // Increment the container view count.
-      this._lContainerNode.data.dynamicViewCount++;
-
-      // Look for the parent node and increment its dynamic view count.
-      const containerParent = getParentLNode(this._lContainerNode) as LElementNode;
-      if (containerParent !== null && containerParent.data !== null) {
-        ngDevMode && assertNodeOfPossibleTypes(containerParent, TNodeType.View, TNodeType.Element);
-        containerParent.data.dynamicViewCount++;
-      }
-    }
     return viewRef;
   }
 

packages/core/src/render3/instructions.ts

@@ -321,7 +321,6 @@ export function createLView<T>(
     bindingIndex: -1,
     template: template,
     context: context,
-    dynamicViewCount: 0,
     lifecycleStage: LifecycleStage.Init,
     queries: null,
     injector: currentView && currentView.injector,
@@ -1455,19 +1454,28 @@ function generateInitialInputs(
 //// ViewContainer & View
 //////////////////////////
 
+/**
+ * Creates a LContainer, either from a container instruction, or for a ViewContainerRef.
+ *
+ * @param parentLNode the LNode in which the container's content will be rendered
+ * @param currentView The parent view of the LContainer
+ * @param template Optional the inline template (ng-template instruction case)
+ * @param isForViewContainerRef Optional a flag indicating the ViewContainerRef case
+ * @returns LContainer
+ */
 export function createLContainer(
-    parentLNode: LNode, currentView: LView, template?: ComponentTemplate<any>): LContainer {
+    parentLNode: LNode, currentView: LView, template?: ComponentTemplate<any>,
+    isForViewContainerRef?: boolean): LContainer {
   ngDevMode && assertNotNull(parentLNode, 'containers should have a parent');
   return <LContainer>{
     views: [],
-    nextIndex: 0,
+    nextIndex: isForViewContainerRef ? null : 0,
     // If the direct parent of the container is a view, its views will need to be added
     // through insertView() when its parent view is being inserted:
     renderParent: canInsertNativeNode(parentLNode, currentView) ? parentLNode : null,
     template: template == null ? null : template,
     next: null,
     parent: currentView,
-    dynamicViewCount: 0,
     queries: null
   };
 }
@@ -1553,7 +1561,7 @@ export function containerRefreshEnd(): void {
   const container = previousOrParentNode as LContainerNode;
   container.native = undefined;
   ngDevMode && assertNodeType(container, TNodeType.Container);
-  const nextIndex = container.data.nextIndex;
+  const nextIndex = container.data.nextIndex !;
 
   // remove extra views at the end of the container
   while (nextIndex < container.data.views.length) {
@@ -1563,7 +1571,9 @@ export function containerRefreshEnd(): void {
 
 function refreshDynamicChildren() {
   for (let current = currentView.child; current !== null; current = current.next) {
-    if (current.dynamicViewCount !== 0 && (current as LContainer).views) {
+    // Note: current can be a LView or a LContainer, but here we are only interested in LContainer.
+    // The distinction is made because nextIndex and views do not exist on LView.
+    if (isLContainer(current)) {
       const container = current as LContainer;
       for (let i = 0; i < container.views.length; i++) {
         const lViewNode = container.views[i];
@@ -1577,6 +1587,10 @@ function refreshDynamicChildren() {
   }
 }
 
+function isLContainer(node: LView | LContainer): node is LContainer {
+  return (node as LContainer).nextIndex == null && (node as LContainer).views != null;
+}
+
 /**
  * Looks for a view with a given view block id inside a provided LContainer.
  * Removes views that need to be deleted in the process.
@@ -1617,7 +1631,7 @@ export function embeddedViewStart(viewBlockId: number): RenderFlags {
       (isParent ? previousOrParentNode : getParentLNode(previousOrParentNode)) as LContainerNode;
   ngDevMode && assertNodeType(container, TNodeType.Container);
   const lContainer = container.data;
-  let viewNode: LViewNode|null = scanForView(container, lContainer.nextIndex, viewBlockId);
+  let viewNode: LViewNode|null = scanForView(container, lContainer.nextIndex !, viewBlockId);
 
   if (viewNode) {
     previousOrParentNode = viewNode;
@@ -1630,7 +1644,7 @@ export function embeddedViewStart(viewBlockId: number): RenderFlags {
         viewBlockId, renderer, getOrCreateEmbeddedTView(viewBlockId, container), null, null,
         LViewFlags.CheckAlways, getCurrentSanitizer());
     if (lContainer.queries) {
-      newView.queries = lContainer.queries.enterView(lContainer.nextIndex);
+      newView.queries = lContainer.queries.enterView(lContainer.nextIndex !);
     }
 
     enterView(
@@ -1678,10 +1692,10 @@ export function embeddedViewEnd(): void {
       // used by the ViewContainerRef must be set.
       setRenderParentInProjectedNodes(lContainer.renderParent, viewNode);
       // it is a new view, insert it into collection of views for a given container
-      insertView(containerNode, viewNode, lContainer.nextIndex);
+      insertView(containerNode, viewNode, lContainer.nextIndex !);
     }
 
-    lContainer.nextIndex++;
+    lContainer.nextIndex !++;
   }
   leaveView(currentView !.parent !);
   ngDevMode && assertEqual(isParent, false, 'isParent');

packages/core/src/render3/interfaces/container.ts

@@ -18,8 +18,11 @@ export interface LContainer {
   /**
    * The next active index in the views array to read or write to. This helps us
    * keep track of where we are in the views array.
+   * In the case the LContainer is created for a ViewContainerRef,
+   * it is set to null to identify this scenario, as indices are "absolute" in that case,
+   * i.e. provided directly by the user of the ViewContainerRef API.
    */
-  nextIndex: number;
+  nextIndex: number|null;
 
   /**
    * This allows us to jump from a container to a sibling container or
@@ -69,12 +72,6 @@ export interface LContainer {
    */
   readonly template: ComponentTemplate<any>|null;
 
-  /**
-   * A count of dynamic views rendered into this container. If this is non-zero, the `views` array
-   * will be traversed when refreshing dynamic views on this container.
-   */
-  dynamicViewCount: number;
-
   /**
    * Queries active for this container - all the views inserted to / removed from
    * this container are reported to queries referenced here.

packages/core/src/render3/interfaces/view.ts

@@ -181,14 +181,6 @@ export interface LView {
    */
   context: {}|RootContext|null;
 
-  /**
-   * A count of dynamic views that are children of this view (indirectly via containers).
-   *
-   * This is used to decide whether to scan children of this view when refreshing dynamic views
-   * after refreshing the view itself.
-   */
-  dynamicViewCount: number;
-
   /**
    * Queries active for this view - nodes from a view are reported to those queries
    */

packages/core/test/bundling/hello_world/bundle.golden_symbols.json

@@ -125,6 +125,9 @@
   {
     "name": "invertObject"
   },
+  {
+    "name": "isLContainer"
+  },
   {
     "name": "isProceduralRenderer"
   },

packages/core/test/bundling/todo/bundle.golden_symbols.json

@@ -494,6 +494,9 @@
   {
     "name": "isJsObject"
   },
+  {
+    "name": "isLContainer"
+  },
   {
     "name": "isListLikeIterable"
   },