From a529d4f4f8e7db16df43fe697aed0551e75371c6 Mon Sep 17 00:00:00 2001
From: JoostK <joost.koehoorn@gmail.com>
Date: Sat, 8 May 2021 17:04:39 +0200
Subject: [PATCH] fix(core): do not retain dynamically compiled components and
 modules (#42003)

The JIT compiler has a mapping from component to the owning NgModule
and tracks whether a certain NgModule class has been verified; these
maps causes any JIT compiled component and NgModule to be retained even
if they are no longer referenced from anywhere else. This commit
switches the maps to `WeakMap` to allow garbage collecting any
components and NgModules that are no longer referenced elsewhere.

Fixes #19997

PR Close #42003
---
 packages/core/src/render3/jit/module.ts | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/packages/core/src/render3/jit/module.ts b/packages/core/src/render3/jit/module.ts
index 50fd3d7536..3df72f8d8e 100644
--- a/packages/core/src/render3/jit/module.ts
+++ b/packages/core/src/render3/jit/module.ts
@@ -373,12 +373,12 @@ function getAnnotation<T>(type: any, name: string): T|null {
  * NgModule the component belongs to. We keep the list of compiled components here so that the
  * TestBed can reset it later.
  */
-let ownerNgModule = new Map<Type<any>, NgModuleType<any>>();
-let verifiedNgModule = new Map<NgModuleType<any>, boolean>();
+let ownerNgModule = new WeakMap<Type<any>, NgModuleType<any>>();
+let verifiedNgModule = new WeakMap<NgModuleType<any>, boolean>();
 
 export function resetCompiledComponents(): void {
-  ownerNgModule = new Map<Type<any>, NgModuleType<any>>();
-  verifiedNgModule = new Map<NgModuleType<any>, boolean>();
+  ownerNgModule = new WeakMap<Type<any>, NgModuleType<any>>();
+  verifiedNgModule = new WeakMap<NgModuleType<any>, boolean>();
   moduleQueue.length = 0;
 }