feat(ivy): support injecting ChangeDetectorRef (#22469)

PR Close #22469

packages/core/src/render3/view_ref.ts

@@ -0,0 +1,84 @@
+/**
+ * @license
+ * Copyright Google Inc. All Rights Reserved.
+ *
+ * Use of this source code is governed by an MIT-style license that can be
+ * found in the LICENSE file at https://angular.io/license
+ */
+
+import {EmbeddedViewRef as viewEngine_EmbeddedViewRef, ViewRef as viewEngine_ViewRef} from '../linker/view_ref';
+
+import {ComponentTemplate} from './interfaces/definition';
+import {LViewNode} from './interfaces/node';
+import {notImplemented} from './util';
+
+export class ViewRef<T> implements viewEngine_EmbeddedViewRef<T> {
+  context: T;
+  rootNodes: any[];
+
+  constructor(context: T|null) { this.context = context !; }
+
+  /** @internal */
+  _setComponentContext(context: T) { this.context = context; }
+
+  destroy(): void { notImplemented(); }
+  destroyed: boolean;
+  onDestroy(callback: Function) { notImplemented(); }
+  markForCheck(): void { notImplemented(); }
+  detach(): void { notImplemented(); }
+  detectChanges(): void { notImplemented(); }
+  checkNoChanges(): void { notImplemented(); }
+  reattach(): void { notImplemented(); }
+}
+
+
+export class EmbeddedViewRef<T> extends ViewRef<T> {
+  /**
+   * @internal
+   */
+  _lViewNode: LViewNode;
+
+  constructor(viewNode: LViewNode, template: ComponentTemplate<T>, context: T) {
+    super(context);
+    this._lViewNode = viewNode;
+  }
+}
+
+/**
+ * Creates a ViewRef bundled with destroy functionality.
+ *
+ * @param context The context for this view
+ * @returns The ViewRef
+ */
+export function createViewRef<T>(context: T): ViewRef<T> {
+  // TODO: add detectChanges back in when implementing ChangeDetectorRef.detectChanges
+  return addDestroyable(new ViewRef(context));
+}
+
+/** Interface for destroy logic. Implemented by addDestroyable. */
+export interface DestroyRef<T> {
+  /** Whether or not this object has been destroyed */
+  destroyed: boolean;
+  /** Destroy the instance and call all onDestroy callbacks. */
+  destroy(): void;
+  /** Register callbacks that should be called onDestroy */
+  onDestroy(cb: Function): void;
+}
+
+/**
+ * Decorates an object with destroy logic (implementing the DestroyRef interface)
+ * and returns the enhanced object.
+ *
+ * @param obj The object to decorate
+ * @returns The object with destroy logic
+ */
+export function addDestroyable<T, C>(obj: any): T&DestroyRef<C> {
+  let destroyFn: Function[]|null = null;
+  obj.destroyed = false;
+  obj.destroy = function() {
+    destroyFn && destroyFn.forEach((fn) => fn());
+    this.destroyed = true;
+  };
+  obj.onDestroy = (fn: Function) => (destroyFn || (destroyFn = [])).push(fn);
+  return obj;
+}