feat(ivy): add basic support for ng-container (#25227)

This commit adds basic support for <ng-container> - most of the
functionality should work as long as <ng-container> is a child of
a regular element.

PR Close #25227

packages/core/src/render3/di.ts

@@ -21,7 +21,7 @@ import {addToViewTree, assertPreviousIsParent, createEmbeddedViewNode, createLCo
 import {VIEWS} from './interfaces/container';
 import {DirectiveDefInternal, RenderFlags} from './interfaces/definition';
 import {LInjector} from './interfaces/injector';
-import {AttributeMarker, LContainerNode, LElementNode, LNode, LViewNode, TContainerNode, TElementNode, TNodeFlags, TNodeType} from './interfaces/node';
+import {AttributeMarker, LContainerNode, LElementContainerNode, LElementNode, LNode, LViewNode, TContainerNode, TElementNode, TNodeFlags, TNodeType} from './interfaces/node';
 import {LQueries, QueryReadType} from './interfaces/query';
 import {Renderer3} from './interfaces/renderer';
 import {DECLARATION_VIEW, DIRECTIVES, HOST_NODE, INJECTOR, LViewData, QUERIES, RENDERER, TVIEW, TView} from './interfaces/view';
@@ -91,7 +91,8 @@ export function bloomAdd(injector: LInjector, type: Type<any>): void {
 
 export function getOrCreateNodeInjector(): LInjector {
   ngDevMode && assertPreviousIsParent();
-  return getOrCreateNodeInjectorForNode(getPreviousOrParentNode() as LElementNode | LContainerNode);
+  return getOrCreateNodeInjectorForNode(
+      getPreviousOrParentNode() as LElementNode | LElementContainerNode | LContainerNode);
 }
 
 /**
@@ -100,7 +101,8 @@ export function getOrCreateNodeInjector(): LInjector {
  * @param node for which an injector should be retrieved / created.
  * @returns Node injector
  */
-export function getOrCreateNodeInjectorForNode(node: LElementNode | LContainerNode): LInjector {
+export function getOrCreateNodeInjectorForNode(
+    node: LElementNode | LElementContainerNode | LContainerNode): LInjector {
   const nodeInjector = node.nodeInjector;
   const parent = getParentLNode(node);
   const parentInjector = parent && parent.nodeInjector;
@@ -637,7 +639,8 @@ class ViewContainerRef implements viewEngine.ViewContainerRef {
   private _viewRefs: viewEngine.ViewRef[] = [];
 
   constructor(
-      private _lContainerNode: LContainerNode, private _hostNode: LElementNode|LContainerNode) {}
+      private _lContainerNode: LContainerNode,
+      private _hostNode: LElementNode|LElementContainerNode|LContainerNode) {}
 
   get element(): ElementRef {
     const injector = getOrCreateNodeInjectorForNode(this._hostNode);

packages/core/src/render3/instructions.ts

@@ -18,7 +18,7 @@ import {executeHooks, executeInitHooks, queueInitHooks, queueLifecycleHooks} fro
 import {ACTIVE_INDEX, LContainer, RENDER_PARENT, VIEWS} from './interfaces/container';
 import {ComponentDefInternal, ComponentQuery, ComponentTemplate, DirectiveDefInternal, DirectiveDefListOrFactory, InitialStylingFlags, PipeDefListOrFactory, RenderFlags} from './interfaces/definition';
 import {LInjector} from './interfaces/injector';
-import {AttributeMarker, InitialInputData, InitialInputs, LContainerNode, LElementNode, LNode, LProjectionNode, LTextNode, LViewNode, PropertyAliasValue, PropertyAliases, TAttributes, TContainerNode, TElementNode, TNode, TNodeFlags, TNodeType} from './interfaces/node';
+import {AttributeMarker, InitialInputData, InitialInputs, LContainerNode, LElementContainerNode, LElementNode, LNode, LProjectionNode, LTextNode, LViewNode, PropertyAliasValue, PropertyAliases, TAttributes, TContainerNode, TElementNode, TNode, TNodeFlags, TNodeType} from './interfaces/node';
 import {CssSelectorList, NG_PROJECT_AS_ATTR_NAME} from './interfaces/projection';
 import {LQueries} from './interfaces/query';
 import {ProceduralRenderer3, RComment, RElement, RText, Renderer3, RendererFactory3, RendererStyleFlags3, isProceduralRenderer} from './interfaces/renderer';
@@ -419,6 +419,9 @@ export function createLNode(
 export function createLNode(
     index: number, type: TNodeType.Projection, native: null, name: null, attrs: TAttributes | null,
     lProjection: null): LProjectionNode;
+export function createLNode(
+    index: number, type: TNodeType.ElementContainer, native: RComment, name: null,
+    attrs: TAttributes | null, data: null): LElementContainerNode;
 export function createLNode(
     index: number, type: TNodeType, native: RText | RElement | RComment | null, name: string | null,
     attrs: TAttributes | null, state?: null | LViewData | LContainer): LElementNode&LTextNode&
@@ -695,6 +698,50 @@ export function element(
   elementEnd();
 }
 
+/**
+ * Creates a logical container for other nodes (<ng-container>) backed by a comment node in the DOM.
+ * The instruction must later be followed by `elementContainerEnd()` call.
+ *
+ * @param index Index of the element in the LViewData array
+ * @param attrs Set of attributes to be used when matching directives.
+ * @param localRefs A set of local reference bindings on the element.
+ *
+ * Even if this instruction accepts a set of attributes no actual attribute values are propoagted to
+ * the DOM (as a comment node can't have attributes). Attributes are here only for directive
+ * matching purposes and setting initial inputs of directives.
+ */
+export function elementContainerStart(
+    index: number, attrs?: TAttributes | null, localRefs?: string[] | null): void {
+  ngDevMode &&
+      assertEqual(viewData[BINDING_INDEX], -1, 'elements should be created before any bindings');
+
+  ngDevMode && ngDevMode.rendererCreateComment++;
+  const native = renderer.createComment(ngDevMode ? 'ng-container' : '');
+
+  ngDevMode && assertDataInRange(index - 1);
+
+  const node: LElementContainerNode =
+      createLNode(index, TNodeType.ElementContainer, native, null, attrs || null, null);
+
+  appendChild(getParentLNode(node), native, viewData);
+  createDirectivesAndLocals(localRefs);
+}
+
+/** Mark the end of the <ng-container>. */
+export function elementContainerEnd(): void {
+  if (isParent) {
+    isParent = false;
+  } else {
+    ngDevMode && assertHasParent();
+    previousOrParentNode = getParentLNode(previousOrParentNode) as LElementContainerNode;
+  }
+
+  ngDevMode && assertNodeType(previousOrParentNode, TNodeType.ElementContainer);
+  const queries = previousOrParentNode.queries;
+  queries && queries.addNode(previousOrParentNode);
+  queueLifecycleHooks(previousOrParentNode.tNode.flags, tView);
+}
+
 /**
  * Create DOM element. The instruction must later be followed by `elementEnd()` call.
  *
@@ -1086,6 +1133,7 @@ export function hostElement(
 export function listener(
     eventName: string, listenerFn: (e?: any) => any, useCapture = false): void {
   ngDevMode && assertPreviousIsParent();
+  ngDevMode && assertNodeOfPossibleTypes(previousOrParentNode, TNodeType.Element);
   const node = previousOrParentNode;
   const native = node.native as RElement;
   ngDevMode && ngDevMode.rendererAddEventListener++;
@@ -1779,6 +1827,7 @@ export function container(
   const currentParent = isParent ? previousOrParentNode : getParentLNode(previousOrParentNode) !;
   const lContainer = createLContainer(currentParent, viewData);
 
+  ngDevMode && ngDevMode.rendererCreateComment++;
   const comment = renderer.createComment(ngDevMode ? 'container' : '');
   const node =
       createLNode(index, TNodeType.Container, comment, tagName || null, attrs || null, lContainer);

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

@@ -11,7 +11,7 @@ import {ElementRef} from '../../linker/element_ref';
 import {TemplateRef} from '../../linker/template_ref';
 import {ViewContainerRef} from '../../linker/view_container_ref';
 
-import {LContainerNode, LElementNode} from './node';
+import {LContainerNode, LElementContainerNode, LElementNode} from './node';
 
 export interface LInjector {
   /**
@@ -26,7 +26,7 @@ export interface LInjector {
    * for DI to retrieve a directive from the data array if injector indicates
    * it is there.
    */
-  readonly node: LElementNode|LContainerNode;
+  readonly node: LElementNode|LElementContainerNode|LContainerNode;
 
   /**
    * The following bloom filter determines whether a directive is available

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

@@ -21,11 +21,12 @@ import {LViewData, TView} from './view';
  * on how to map a particular set of bits in LNode.flags to the node type.
  */
 export const enum TNodeType {
-  Container = 0b00,
-  Projection = 0b01,
-  View = 0b10,
-  Element = 0b11,
-  ViewOrElement = 0b10,
+  Container = 0b000,
+  Projection = 0b001,
+  View = 0b010,
+  Element = 0b011,
+  ViewOrElement = 0b010,
+  ElementContainer = 0b100,
 }
 
 /**
@@ -118,6 +119,13 @@ export interface LElementNode extends LNode {
   readonly data: LViewData|null;
 }
 
+/** LNode representing <ng-container>. */
+export interface LElementContainerNode extends LNode {
+  /** The DOM comment associated with this node. */
+  readonly native: RComment;
+  readonly data: null;
+}
+
 /** LNode representing a #text node. */
 export interface LTextNode extends LNode {
   /** The text node associated with this node. */

packages/core/src/render3/ng_dev_mode.ts

@@ -29,6 +29,7 @@ declare global {
     rendererDestroyNode: number;
     rendererMoveNode: number;
     rendererRemoveNode: number;
+    rendererCreateComment: number;
   }
 }
 
@@ -61,6 +62,7 @@ export function ngDevModeResetPerfCounters() {
     rendererDestroyNode: 0,
     rendererMoveNode: 0,
     rendererRemoveNode: 0,
+    rendererCreateComment: 0,
   };
 }
 

packages/core/src/render3/node_manipulation.ts

@@ -9,7 +9,7 @@
 import {assertDefined} from './assert';
 import {callHooks} from './hooks';
 import {LContainer, RENDER_PARENT, VIEWS, unusedValueExportToPlacateAjd as unused1} from './interfaces/container';
-import {LContainerNode, LElementNode, LNode, LProjectionNode, LTextNode, LViewNode, TNode, TNodeFlags, TNodeType, unusedValueExportToPlacateAjd as unused2} from './interfaces/node';
+import {LContainerNode, LElementContainerNode, LElementNode, LNode, LProjectionNode, LTextNode, LViewNode, TNode, TNodeFlags, TNodeType, unusedValueExportToPlacateAjd as unused2} from './interfaces/node';
 import {unusedValueExportToPlacateAjd as unused3} from './interfaces/projection';
 import {ProceduralRenderer3, RComment, RElement, RNode, RText, Renderer3, isProceduralRenderer, unusedValueExportToPlacateAjd as unused4} from './interfaces/renderer';
 import {CLEANUP, CONTAINER_INDEX, DIRECTIVES, FLAGS, HEADER_OFFSET, HOST_NODE, HookData, LViewData, LViewFlags, NEXT, PARENT, QUERIES, RENDERER, TVIEW, unusedValueExportToPlacateAjd as unused5} from './interfaces/view';
@@ -38,11 +38,14 @@ export function getChildLNode(node: LNode): LNode|null {
 }
 
 /** Retrieves the parent LNode of a given node. */
-export function getParentLNode(node: LContainerNode | LElementNode | LTextNode | LProjectionNode):
-    LElementNode|LViewNode;
+export function getParentLNode(
+    node: LContainerNode | LElementNode | LElementContainerNode | LTextNode |
+    LProjectionNode): LElementNode|LElementContainerNode|LViewNode;
 export function getParentLNode(node: LViewNode): LContainerNode|null;
-export function getParentLNode(node: LNode): LElementNode|LContainerNode|LViewNode|null;
-export function getParentLNode(node: LNode): LElementNode|LContainerNode|LViewNode|null {
+export function getParentLNode(node: LNode): LElementNode|LElementContainerNode|LContainerNode|
+    LViewNode|null;
+export function getParentLNode(node: LNode): LElementNode|LElementContainerNode|LContainerNode|
+    LViewNode|null {
   if (node.tNode.index === -1 && node.tNode.type === TNodeType.View) {
     // This is a dynamically created view inside a dynamic container.
     // If the host index is -1, the view has not yet been inserted, so it has no parent.
@@ -518,9 +521,10 @@ function executePipeOnDestroys(viewData: LViewData): void {
  */
 export function canInsertNativeNode(parent: LNode, currentView: LViewData): boolean {
   // We can only insert into a Component or View. Any other type should be an Error.
-  ngDevMode && assertNodeOfPossibleTypes(parent, TNodeType.Element, TNodeType.View);
+  ngDevMode && assertNodeOfPossibleTypes(
+                   parent, TNodeType.Element, TNodeType.ElementContainer, TNodeType.View);
 
-  if (parent.tNode.type === TNodeType.Element) {
+  if (parent.tNode.type === TNodeType.Element || parent.tNode.type === TNodeType.ElementContainer) {
     // Parent is an element.
     if (parent.view !== currentView) {
       // If the Parent view is not the same as current view than we are inserting across
@@ -584,6 +588,12 @@ export function appendChild(parent: LNode, child: RNode | null, currentView: LVi
       isProceduralRenderer(renderer) ?
           renderer.insertBefore(renderParent !.native, child, beforeNode) :
           renderParent !.native.insertBefore(child, beforeNode, true);
+    } else if (parent.tNode.type === TNodeType.ElementContainer) {
+      const beforeNode = parent.native;
+      const renderParent = getParentLNode(parent) as LElementNode;
+      isProceduralRenderer(renderer) ?
+          renderer.insertBefore(renderParent !.native, child, beforeNode) :
+          renderParent !.native.insertBefore(child, beforeNode, true);
     } else {
       isProceduralRenderer(renderer) ? renderer.appendChild(parent.native !as RElement, child) :
                                        parent.native !.appendChild(child);
@@ -621,8 +631,9 @@ export function removeChild(parent: LNode, child: RNode | null, currentView: LVi
  * @param currentView Current LView
  */
 export function appendProjectedNode(
-    node: LElementNode | LTextNode | LContainerNode, currentParent: LElementNode | LViewNode,
-    currentView: LViewData, renderParent: LElementNode): void {
+    node: LElementNode | LElementContainerNode | LTextNode | LContainerNode,
+    currentParent: LElementNode | LElementContainerNode | LViewNode, currentView: LViewData,
+    renderParent: LElementNode): void {
   appendChild(currentParent, node.native, currentView);
   if (node.tNode.type === TNodeType.Container) {
     // The node we are adding is a container and we are adding it to an element which

packages/core/test/render3/integration_spec.ts

@@ -6,16 +6,17 @@
  * found in the LICENSE file at https://angular.io/license
  */
 
+import {ElementRef} from '@angular/core';
 import {RenderFlags} from '@angular/core/src/render3';
 
-import {defineComponent, defineDirective} from '../../src/render3/index';
-import {NO_CHANGE, bind, container, containerRefreshEnd, containerRefreshStart, element, elementAttribute, elementClassProp, elementEnd, elementProperty, elementStart, elementStyleProp, elementStyling, elementStylingApply, embeddedViewEnd, embeddedViewStart, interpolation1, interpolation2, interpolation3, interpolation4, interpolation5, interpolation6, interpolation7, interpolation8, interpolationV, load, loadDirective, projection, projectionDef, text, textBinding} from '../../src/render3/instructions';
+import {AttributeMarker, defineComponent, defineDirective, injectElementRef} from '../../src/render3/index';
+import {NO_CHANGE, bind, container, containerRefreshEnd, containerRefreshStart, element, elementAttribute, elementClassProp, elementContainerEnd, elementContainerStart, elementEnd, elementProperty, elementStart, elementStyleProp, elementStyling, elementStylingApply, embeddedViewEnd, embeddedViewStart, interpolation1, interpolation2, interpolation3, interpolation4, interpolation5, interpolation6, interpolation7, interpolation8, interpolationV, listener, load, loadDirective, projection, projectionDef, text, textBinding} from '../../src/render3/instructions';
 import {InitialStylingFlags} from '../../src/render3/interfaces/definition';
 import {HEADER_OFFSET} from '../../src/render3/interfaces/view';
 import {sanitizeUrl} from '../../src/sanitization/sanitization';
 import {Sanitizer, SecurityContext} from '../../src/sanitization/security';
 
-import {ComponentFixture, containerEl, renderToHtml} from './render_util';
+import {ComponentFixture, TemplateFixture, containerEl, renderToHtml} from './render_util';
 
 describe('render3 integration test', () => {
 
@@ -418,6 +419,104 @@ describe('render3 integration test', () => {
 
   });
 
+  describe('ng-container', () => {
+
+    it('should insert as a child of a regular element', () => {
+
+      /**
+       * <div>before|<ng-container>Greetings<span></span></ng-container>|after</div>
+       */
+      function Template() {
+        elementStart(0, 'div');
+        {
+          text(1, 'before|');
+          elementContainerStart(2);
+          {
+            text(3, 'Greetings');
+            element(4, 'span');
+          }
+          elementContainerEnd();
+          text(5, '|after');
+        }
+        elementEnd();
+      }
+
+      const fixture = new TemplateFixture(Template);
+      expect(fixture.html).toEqual('<div>before|Greetings<span></span>|after</div>');
+    });
+
+    it('should support directives and inject ElementRef', () => {
+
+      class Directive {
+        constructor(public elRef: ElementRef) {}
+
+        static ngDirectiveDef = defineDirective({
+          type: Directive,
+          selectors: [['', 'dir', '']],
+          factory: () => new Directive(injectElementRef()),
+        });
+      }
+
+      let directive: Directive;
+
+      /**
+       * <div><ng-container dir></ng-container></div>
+       */
+      function Template() {
+        elementStart(0, 'div');
+        {
+          elementContainerStart(1, [AttributeMarker.SelectOnly, 'dir']);
+          elementContainerEnd();
+          directive = loadDirective<Directive>(0);
+        }
+        elementEnd();
+      }
+
+      const fixture = new TemplateFixture(Template, () => {}, [Directive]);
+      expect(fixture.html).toEqual('<div></div>');
+      expect(directive !.elRef.nativeElement.nodeType).toBe(Node.COMMENT_NODE);
+    });
+
+    it('should not set any attributes', () => {
+
+      /**
+       * <div><ng-container id="foo"></ng-container></div>
+       */
+      function Template() {
+        elementStart(0, 'div');
+        {
+          elementContainerStart(1, ['id', 'foo']);
+          elementContainerEnd();
+        }
+        elementEnd();
+      }
+
+      const fixture = new TemplateFixture(Template);
+      expect(fixture.html).toEqual('<div></div>');
+    });
+
+    it('should throw when trying to add event listener', () => {
+
+      /**
+       * <div><ng-container (click)="..."></ng-container></div>
+       */
+      function Template() {
+        elementStart(0, 'div');
+        {
+          elementContainerStart(1);
+          {
+            listener('click', function() {});
+          }
+          elementContainerEnd();
+        }
+        elementEnd();
+      }
+
+      expect(() => { new TemplateFixture(Template); }).toThrow();
+    });
+
+  });
+
   describe('tree', () => {
     interface Tree {
       beforeLabel?: string;

packages/core/test/render3/query_spec.ts

@@ -12,7 +12,7 @@ import {ElementRef, TemplateRef, ViewContainerRef} from '@angular/core';
 import {EventEmitter} from '../..';
 import {QUERY_READ_CONTAINER_REF, QUERY_READ_ELEMENT_REF, QUERY_READ_FROM_NODE, QUERY_READ_TEMPLATE_REF, getOrCreateNodeInjectorForNode, getOrCreateTemplateRef} from '../../src/render3/di';
 import {AttributeMarker, QueryList, defineComponent, defineDirective, detectChanges, injectViewContainerRef} from '../../src/render3/index';
-import {bind, container, containerRefreshEnd, containerRefreshStart, element, elementEnd, elementProperty, elementStart, embeddedViewEnd, embeddedViewStart, load, loadDirective, loadElement, loadQueryList, registerContentQuery} from '../../src/render3/instructions';
+import {bind, container, containerRefreshEnd, containerRefreshStart, element, elementContainerEnd, elementContainerStart, elementEnd, elementProperty, elementStart, embeddedViewEnd, embeddedViewStart, load, loadDirective, loadElement, loadQueryList, registerContentQuery} from '../../src/render3/instructions';
 import {RenderFlags} from '../../src/render3/interfaces/definition';
 import {query, queryRefresh} from '../../src/render3/query';
 
@@ -364,6 +364,43 @@ describe('query', () => {
         expect(qList.first.nativeElement).toEqual(elToQuery);
       });
 
+      it('should query for <ng-container> and read ElementRef with a native element pointing to comment node',
+         () => {
+           let elToQuery;
+           /**
+            * <ng-container #foo></ng-container>
+            * class Cmpt {
+            *  @ViewChildren('foo') query;
+            * }
+            */
+           const Cmpt = createComponent(
+               'cmpt',
+               function(rf: RenderFlags, ctx: any) {
+                 if (rf & RenderFlags.Create) {
+                   elementContainerStart(1, null, ['foo', '']);
+                   elToQuery = loadElement(1).native;
+                   elementContainerEnd();
+                 }
+               },
+               [], [],
+               function(rf: RenderFlags, ctx: any) {
+                 if (rf & RenderFlags.Create) {
+                   query(0, ['foo'], false, QUERY_READ_ELEMENT_REF);
+                 }
+                 if (rf & RenderFlags.Update) {
+                   let tmp: any;
+                   queryRefresh(tmp = load<QueryList<any>>(0)) &&
+                       (ctx.query = tmp as QueryList<any>);
+                 }
+               });
+
+           const cmptInstance = renderComponent(Cmpt);
+           const qList = (cmptInstance.query as QueryList<any>);
+           expect(qList.length).toBe(1);
+           expect(isElementRef(qList.first)).toBeTruthy();
+           expect(qList.first.nativeElement).toEqual(elToQuery);
+         });
+
       it('should read ViewContainerRef from element nodes when explicitly asked for', () => {
         /**
          * <div #foo></div>

packages/core/test/render3/render_util.ts

@@ -222,7 +222,8 @@ export function toHtml<T>(componentOrElement: T | RElement): string {
         .replace(/^<div fixture="mark">/, '')
         .replace(/<\/div>$/, '')
         .replace(' style=""', '')
-        .replace(/<!--container-->/g, '');
+        .replace(/<!--container-->/g, '')
+        .replace(/<!--ng-container-->/g, '');
   }
 }