fix(ivy): report results to appropriate content queries (#24673)

PR Close #24673

packages/core/src/render3/instructions.ts

@@ -127,9 +127,19 @@ let tView: TView;
 
 let currentQueries: LQueries|null;
 
+/**
+ * Query instructions can ask for "current queries" in 2 different cases:
+ * - when creating view queries (at the root of a component view, before any node is created - in
+ * this case currentQueries points to view queries)
+ * - when creating content queries (inb this previousOrParentNode points to a node on which we
+ * create content queries).
+ */
 export function getCurrentQueries(QueryType: {new (): LQueries}): LQueries {
   // top level variables should not be exported for performance reasons (PERF_NOTES.md)
-  return currentQueries || (currentQueries = (previousOrParentNode.queries || new QueryType()));
+  return currentQueries ||
+      (currentQueries =
+           (previousOrParentNode.queries && previousOrParentNode.queries.clone() ||
+            new QueryType()));
 }
 
 /**

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

@@ -13,7 +13,14 @@ import {LNode} from './node';
 /** Used for tracking queries (e.g. ViewChild, ContentChild). */
 export interface LQueries {
   /**
-   * Used to ask querieis if those should be cloned to the child element.
+   * Ask queries to prepare copy of itself. This assures that tracking new queries on child nodes
+   * doesn't mutate list of queries tracked on a parent node. We will clone LQueries before
+   * constructing content queries.
+   */
+  clone(): LQueries|null;
+
+  /**
+   * Used to ask queries if those should be cloned to the child element.
    *
    * For example in the case of deep queries the `child()` returns
    * queries for the child node. In case of shallow queries it returns

packages/core/src/render3/query.ts

@@ -94,8 +94,6 @@ export class LQueries_ implements LQueries {
   track<T>(
       queryList: viewEngine_QueryList<T>, predicate: Type<T>|string[], descend?: boolean,
       read?: QueryReadType<T>|Type<T>): void {
-    // TODO(misko): This is not right. In case of inherited state, a calling track will incorrectly
-    // mutate parent.
     if (descend) {
       this.deep = createQuery(this.deep, queryList, predicate, read != null ? read : null);
     } else {
@@ -103,6 +101,8 @@ export class LQueries_ implements LQueries {
     }
   }
 
+  clone(): LQueries|null { return this.deep ? new LQueries_(this.deep) : null; }
+
   child(): LQueries|null {
     if (this.deep === null) {
       // if we don't have any deep queries then no need to track anything more.