feat: support queries for elements with local names (#20855)

PR Close #20855

packages/core/src/render3/di.ts

@@ -11,7 +11,7 @@
 import * as viewEngine from '../core';
 
 import {BLOOM_SIZE, NG_ELEMENT_ID, getOrCreateNodeInjector} from './instructions';
-import {LContainer, LNodeFlags, LNodeInjector} from './l_node';
+import {LContainer, LElement, LNodeFlags, LNodeInjector} from './l_node';
 import {ComponentTemplate, DirectiveDef} from './public_interfaces';
 import {notImplemented, stringify} from './util';
 
@@ -200,16 +200,24 @@ export function bloomFindPossibleInjector(
   return null;
 }
 
+/**
+ * Creates an ElementRef for a given node and stores it on the injector.
+ * Or, if the ElementRef already exists, retrieves the existing ElementRef.
+ *
+ * @returns The ElementRef instance to use
+ */
+export function injectElementRefForNode(node?: LElement | LContainer): viewEngine.ElementRef {
+  let di = getOrCreateNodeInjector(node);
+  return di.elementRef || (di.elementRef = new ElementRef(di.node.native));
+}
+
 /**
  * Creates an ElementRef and stores it on the injector. Or, if the ElementRef already
  * exists, retrieves the existing ElementRef.
  *
  * @returns The ElementRef instance to use
  */
-export function injectElementRef(): viewEngine.ElementRef {
+export const injectElementRef: () => viewEngine.ElementRef = injectElementRefForNode;
-  let di = getOrCreateNodeInjector();
-  return di.elementRef || (di.elementRef = new ElementRef(di.node.native));
-}
 
 /** A ref to a node's native element. */
 class ElementRef implements viewEngine.ElementRef {

packages/core/src/render3/instructions.ts

@@ -339,9 +339,9 @@ export function bloomAdd(injector: LNodeInjector, type: Type<any>): void {
   }
 }
 
-export function getOrCreateNodeInjector(): LNodeInjector {
+export function getOrCreateNodeInjector(node?: LElement | LContainer): LNodeInjector {
-  ngDevMode && assertPreviousIsParent();
+  ngDevMode && !node && assertPreviousIsParent();
-  const node = previousOrParentNode as LElement | LContainer;
+  node = node || previousOrParentNode as LElement | LContainer;
   const nodeInjector = node.nodeInjector;
   const parentInjector = node.parent && node.parent.nodeInjector;
   if (nodeInjector != parentInjector) {
@@ -376,13 +376,15 @@ export function getOrCreateNodeInjector(): LNodeInjector {
  * @param index Index of the element in the data array
  * @param nameOrComponentDef Name of the DOM Node or `ComponentDef`.
  * @param attrs Statically bound set of attributes to be written into the DOM element on creation.
+ * @param localName A name under which a given element is exported.
  *
  * Attributes are passed as an array of strings where elements with an even index hold an attribute
  * name and elements with an odd index hold an attribute value, ex.:
  * ['id', 'warning5', 'class', 'alert']
  */
 export function elementStart(
-    index: number, nameOrComponentDef?: string | ComponentDef<any>, attrs?: string[]): RElement {
+    index: number, nameOrComponentDef?: string | ComponentDef<any>, attrs?: string[] | null,
+    localName?: string): RElement {
   let node: LElement;
   let native: RElement;
 
@@ -413,7 +415,8 @@ export function elementStart(
 
       if (node.staticData == null) {
         ngDevMode && assertDataInRange(index - 1);
-        node.staticData = ngStaticData[index] = createNodeStatic(name, attrs || null, null);
+        node.staticData = ngStaticData[index] =
+            createNodeStatic(name, attrs || null, null, localName || null);
       }
 
       if (attrs) setUpAttributes(native, attrs);
@@ -610,10 +613,11 @@ export function elementProperty<T>(index: number, propName: string, value: T | N
  */
 function createNodeStatic(
     tagName: string | null, attrs: string[] | null,
-    containerStatic: (LNodeStatic | null)[][] | null): LNodeStatic {
+    containerStatic: (LNodeStatic | null)[][] | null, localName: string | null): LNodeStatic {
   return {
-    tagName,
+    tagName: tagName,
-    attrs,
+    attrs: attrs,
+    localName: localName,
     initialInputs: undefined,
     inputs: undefined,
     outputs: undefined,
@@ -973,7 +977,8 @@ export function containerStart(
   });
 
   if (node.staticData == null) {
-    node.staticData = ngStaticData[index] = createNodeStatic(tagName || null, attrs || null, []);
+    node.staticData = ngStaticData[index] =
+        createNodeStatic(tagName || null, attrs || null, [], null);
   }
 
   // Containers are added to the current view tree instead of their embedded views
@@ -1696,7 +1701,7 @@ function valueInData<T>(data: any[], index: number, value?: T): T {
   return value !;
 }
 
-export function query<T>(predicate: Type<any>| any[], descend?: boolean): QueryList<T> {
+export function query<T>(predicate: Type<any>| string[], descend?: boolean): QueryList<T> {
   ngDevMode && assertPreviousIsParent();
   const queryList = new QueryList<T>();
   const query = currentQuery || (currentQuery = new QueryState_());

packages/core/src/render3/l_node_static.ts

@@ -38,6 +38,11 @@ export interface LNodeStatic {
    */
   attrs: string[]|null;
 
+  /**
+   * A local name under which a given element is exported in a view.
+   */
+  localName: string|null;
+
   /**
    * This property contains information about input properties that
    * need to be set once from attribute data.

packages/core/src/render3/query.ts

@@ -12,8 +12,9 @@ import {Observable} from 'rxjs/Observable';
 import * as viewEngine from '../core';
 
 import {assertNotNull} from './assert';
+import {injectElementRefForNode} from './di';
 import {QueryState} from './interfaces';
-import {LContainer, LNode, LNodeFlags, LView} from './l_node';
+import {LContainer, LElement, LNode, LNodeFlags, LView} from './l_node';
 
 
 
@@ -37,16 +38,9 @@ export interface QueryPredicate<T> {
   type: viewEngine.Type<T>|null;
 
   /**
-   * If selector then contains the selector parts where:
+   * If selector then contains local names to query for.
-   * - even index:
-   *    - `null`: represents a tag name
-   *    - `"#""`: represents a reference name
-   *    - `string`: name of the attribute
-   * - odd index:
-   *    - `null`: any value will match
-   *    - `string`: the value which mast match.
    */
-  selector: any[]|null;
+  selector: string[]|null;
 
   /**
    * Values which have been located.
@@ -63,7 +57,7 @@ export class QueryState_ implements QueryState {
   constructor(deep?: QueryPredicate<any>) { this.deep = deep == null ? null : deep; }
 
   track<T>(
-      queryList: viewEngine.QueryList<T>, predicate: viewEngine.Type<T>|any[],
+      queryList: viewEngine.QueryList<T>, predicate: viewEngine.Type<T>|string[],
       descend?: boolean): void {
     // TODO(misko): This is not right. In case of inherited state, a calling track will incorrectly
     // mutate parent.
@@ -117,6 +111,16 @@ function add(predicate: QueryPredicate<any>| null, node: LNode) {
           predicate.values.push(node.view.data[i]);
         }
       }
+    } else {
+      const staticData = node.staticData;
+      if (staticData && staticData.localName) {
+        const selector = predicate.selector !;
+        for (let i = 0; i < selector.length; i++) {
+          if (selector[i] === staticData.localName) {
+            predicate.values.push(injectElementRefForNode(node as LElement | LContainer));
+          }
+        }
+      }
     }
     predicate = predicate.next;
   }
@@ -124,7 +128,7 @@ function add(predicate: QueryPredicate<any>| null, node: LNode) {
 
 function createPredicate<T>(
     previous: QueryPredicate<any>| null, queryList: QueryList<T>,
-    predicate: viewEngine.Type<T>| any[]): QueryPredicate<T> {
+    predicate: viewEngine.Type<T>| string[]): QueryPredicate<T> {
   const isArray = Array.isArray(predicate);
   const values = <any>[];
   if ((queryList as any as QueryList_<T>)._valuesTree === null) {
@@ -134,7 +138,7 @@ function createPredicate<T>(
     next: previous,
     list: queryList,
     type: isArray ? null : predicate as viewEngine.Type<T>,
-    selector: isArray ? predicate as any[] : null,
+    selector: isArray ? predicate as string[] : null,
     values: values
   };
 }

packages/core/test/render3/node_selector_matcher_spec.ts

@@ -14,6 +14,7 @@ function testLStaticData(tagName: string, attrs: string[] | null): LNodeStatic {
   return {
     tagName,
     attrs,
+    localName: null,
     initialInputs: undefined,
     inputs: undefined,
     outputs: undefined,

packages/core/test/render3/query_spec.ts

@@ -48,4 +48,69 @@ describe('query', () => {
     expect((parent.query0 as QueryList<any>).toArray()).toEqual([child1]);
     expect((parent.query1 as QueryList<any>).toArray()).toEqual([child1, child2]);
   });
+
+  describe('local names', () => {
+
+    it('should query for a single element', () => {
+
+      let elToQuery;
+      /**
+       * <div #foo></div>
+       * <div></div>
+       * class Cmpt {
+       *  @ViewChildren('foo') query;
+       * }
+       */
+      const Cmpt = createComponent('cmpt', function(ctx: any, cm: boolean) {
+        let tmp: any;
+        if (cm) {
+          m(0, Q(['foo']));
+          elToQuery = E(1, 'div', [], 'foo');
+          e();
+          E(2, 'div');
+          e();
+        }
+        qR(tmp = m<QueryList<any>>(0)) && (ctx.query = tmp as QueryList<any>);
+      });
+
+      const cmptInstance = renderComponent(Cmpt);
+      const query = (cmptInstance.query as QueryList<any>);
+      expect(query.length).toBe(1);
+      expect(query.first.nativeElement).toEqual(elToQuery);
+    });
+
+    it('should query for multiple elements', () => {
+
+      let el1ToQuery;
+      let el2ToQuery;
+      /**
+       * <div #foo></div>
+       * <div></div>
+       * <div #bar></div>
+       * class Cmpt {
+       *  @ViewChildren('foo,bar') query;
+       * }
+       */
+      const Cmpt = createComponent('cmpt', function(ctx: any, cm: boolean) {
+        let tmp: any;
+        if (cm) {
+          m(0, Q(['foo', 'bar']));
+          el1ToQuery = E(1, 'div', null, 'foo');
+          e();
+          E(2, 'div');
+          e();
+          el2ToQuery = E(3, 'div', null, 'bar');
+          e();
+        }
+        qR(tmp = m<QueryList<any>>(0)) && (ctx.query = tmp as QueryList<any>);
+      });
+
+      const cmptInstance = renderComponent(Cmpt);
+      const query = (cmptInstance.query as QueryList<any>);
+      expect(query.length).toBe(2);
+      expect(query.first.nativeElement).toEqual(el1ToQuery);
+      expect(query.last.nativeElement).toEqual(el2ToQuery);
+    });
+
+  });
 });