From 4e413d9240259fca1b1e548c5c405e646f8e68c8 Mon Sep 17 00:00:00 2001
From: Andrew Kushnir <akushnir@google.com>
Date: Wed, 27 Apr 2022 18:17:25 -0700
Subject: [PATCH] fix(core): support nested arrays of providers in
 `EnvironmentInjector` (#45789)

This commit updates the `EnvironmentInjector` logic to support arrays of providers as an argument(for example, when an injector is created via `createEnvironmentInjector` function).

PR Close #45789
---
 packages/core/src/di/r3_injector.ts           |  6 ++---
 .../env_injector_standalone_spec.ts           | 25 ++++++++++++++++++-
 2 files changed, 27 insertions(+), 4 deletions(-)

diff --git a/packages/core/src/di/r3_injector.ts b/packages/core/src/di/r3_injector.ts
index 4a3194bb652..5f37ccc248a 100644
--- a/packages/core/src/di/r3_injector.ts
+++ b/packages/core/src/di/r3_injector.ts
@@ -14,7 +14,7 @@ import {Type} from '../interface/type';
 import {getComponentDef} from '../render3/definition';
 import {FactoryFn, getFactoryDef} from '../render3/definition_factory';
 import {throwCyclicDependencyError, throwInvalidProviderError, throwMixedMultiProviderError} from '../render3/errors_di';
-import {flatten, newArray} from '../util/array_utils';
+import {deepForEach, flatten, newArray} from '../util/array_utils';
 import {EMPTY_ARRAY} from '../util/empty';
 import {stringify} from '../util/stringify';
 
@@ -125,9 +125,9 @@ export class R3Injector extends EnvironmentInjector {
       readonly scopes: Set<InjectorScope>) {
     super();
     // Start off by creating Records for every provider.
-    for (const provider of providers) {
+    deepForEach(providers, provider => {
       this.processProvider(provider as SingleProvider);
-    }
+    });
 
     // Make sure the INJECTOR token provides this injector.
     this.records.set(INJECTOR, makeRecord(undefined, this));
diff --git a/packages/core/test/acceptance/env_injector_standalone_spec.ts b/packages/core/test/acceptance/env_injector_standalone_spec.ts
index f98d857da30..937ba941ef6 100644
--- a/packages/core/test/acceptance/env_injector_standalone_spec.ts
+++ b/packages/core/test/acceptance/env_injector_standalone_spec.ts
@@ -6,7 +6,7 @@
  * found in the LICENSE file at https://angular.io/license
  */
 
-import {Component, createEnvironmentInjector, importProvidersFrom, NgModule} from '@angular/core';
+import {Component, createEnvironmentInjector, importProvidersFrom, InjectionToken, NgModule} from '@angular/core';
 
 describe('environement injector and standalone components', () => {
   it('should see providers from modules imported by standalone components', () => {
@@ -70,4 +70,27 @@ describe('environement injector and standalone components', () => {
 
     expect(services.length).toBe(1);
   });
+
+  it('should support nested arrays of providers', () => {
+    const A = new InjectionToken('A');
+    const B = new InjectionToken('B');
+    const C = new InjectionToken('C');
+    const MULTI = new InjectionToken('D');
+
+    const providers = [
+      {provide: MULTI, useValue: 1, multi: true}, {provide: A, useValue: 'A'},  //
+      [
+        {provide: B, useValue: 'B'},
+        [
+          {provide: C, useValue: 'C'},
+          {provide: MULTI, useValue: 2, multi: true},
+        ]
+      ]
+    ];
+    const envInjector = createEnvironmentInjector(providers);
+    expect(envInjector.get(A)).toBe('A');
+    expect(envInjector.get(B)).toBe('B');
+    expect(envInjector.get(C)).toBe('C');
+    expect(envInjector.get(MULTI)).toEqual([1, 2]);
+  });
 });