fix(ivy): semantic module check incorrectly handles nested arrays (#30993)

In View Engine, developers can pass bootstrap and entry components
as nested arrays. e.g.

```ts
export const MyOtherEntryComponents = [A, B, C]

@NgModule({
  entryComponents: [MyComp, MyOtherEntryComponents]
})
```

Currently using nested arrays for these properties causes
unexpected errors to be reported in Ivy since the semantic
NgModule checks aren't properly recursing into the nested
entry/bootstrap components. This issue has been unveiled by
enabling the strict function parameter checks.

PR Close #30993

packages/core/src/di/r3_injector.ts

@@ -11,6 +11,7 @@ import '../util/ng_dev_mode';
 import {OnDestroy} from '../interface/lifecycle_hooks';
 import {Type} from '../interface/type';
 import {throwCyclicDependencyError, throwInvalidProviderError, throwMixedMultiProviderError} from '../render3/errors';
+import {deepForEach} from '../util/array_utils';
 import {stringify} from '../util/stringify';
 
 import {resolveForwardRef} from './forward_ref';
@@ -497,10 +498,6 @@ function makeRecord<T>(
   };
 }
 
-function deepForEach<T>(input: (T | any[])[], fn: (value: T) => void): void {
-  input.forEach(value => Array.isArray(value) ? deepForEach(value, fn) : fn(value));
-}
-
 function isValueProvider(value: SingleProvider): value is ValueProvider {
   return value !== null && typeof value == 'object' && USE_VALUE in value;
 }

packages/core/src/render3/jit/module.ts

@@ -13,7 +13,7 @@ import {reflectDependencies} from '../../di/jit/util';
 import {Type} from '../../interface/type';
 import {Component} from '../../metadata';
 import {ModuleWithProviders, NgModule, NgModuleDef, NgModuleTransitiveScopes} from '../../metadata/ng_module';
-import {flatten} from '../../util/array_utils';
+import {deepForEach, flatten} from '../../util/array_utils';
 import {assertDefined} from '../../util/assert';
 import {getComponentDef, getDirectiveDef, getNgModuleDef, getPipeDef} from '../definition';
 import {NG_COMPONENT_DEF, NG_DIRECTIVE_DEF, NG_MODULE_DEF, NG_PIPE_DEF} from '../fields';
@@ -200,9 +200,10 @@ function verifySemanticsOfNgModuleDef(
           verifySemanticsOfNgModuleImport(mod, moduleType);
           verifySemanticsOfNgModuleDef(mod, false, moduleType);
         });
-    ngModule.bootstrap && ngModule.bootstrap.forEach(verifyCorrectBootstrapType);
-    ngModule.bootstrap && ngModule.bootstrap.forEach(verifyComponentIsPartOfNgModule);
-    ngModule.entryComponents && ngModule.entryComponents.forEach(verifyComponentIsPartOfNgModule);
+    ngModule.bootstrap && deepForEach(ngModule.bootstrap, verifyCorrectBootstrapType);
+    ngModule.bootstrap && deepForEach(ngModule.bootstrap, verifyComponentIsPartOfNgModule);
+    ngModule.entryComponents &&
+        deepForEach(ngModule.entryComponents, verifyComponentIsPartOfNgModule);
   }
 
   // Throw Error if any errors were detected.
@@ -273,7 +274,7 @@ function verifySemanticsOfNgModuleDef(
       // We know we are component
       const component = getAnnotation<Component>(type, 'Component');
       if (component && component.entryComponents) {
-        component.entryComponents.forEach(verifyComponentIsPartOfNgModule);
+        deepForEach(component.entryComponents, verifyComponentIsPartOfNgModule);
       }
     }
   }

packages/core/src/util/array_utils.ts

@@ -38,4 +38,8 @@ export function flatten(list: any[], dst?: any[]): any[] {
     }
   }
   return dst;
-}
+}
+
+export function deepForEach<T>(input: (T | any[])[], fn: (value: T) => void): void {
+  input.forEach(value => Array.isArray(value) ? deepForEach(value, fn) : fn(value));
+}

packages/core/test/acceptance/ng_module_spec.ts

@@ -0,0 +1,77 @@
+/**
+ * @license
+ * Copyright Google Inc. All Rights Reserved.
+ *
+ * Use of this source code is governed by an MIT-style license that can be
+ * found in the LICENSE file at https://angular.io/license
+ */
+
+import {Component, NgModule} from '@angular/core';
+import {TestBed} from '@angular/core/testing';
+
+describe('NgModule', () => {
+  @Component({template: 'hello'})
+  class TestCmp {
+  }
+
+  @Component({template: 'hello'})
+  class TestCmp2 {
+  }
+
+  describe('entryComponents', () => {
+    it('should throw when specified entry component is not added to a module', () => {
+      @NgModule({entryComponents: [TestCmp, [TestCmp2]]})
+      class MyModule {
+      }
+
+      TestBed.configureTestingModule({imports: [MyModule]});
+
+      expect(() => {
+        TestBed.createComponent(TestCmp);
+        TestBed.createComponent(TestCmp2);
+      }).toThrowError(/not part of any NgModule/);
+    });
+
+    it('should not throw when specified entry component is added to a module', () => {
+      @NgModule({declarations: [TestCmp, TestCmp2], entryComponents: [TestCmp, [TestCmp2]]})
+      class MyModule {
+      }
+
+      TestBed.configureTestingModule({imports: [MyModule]});
+
+      expect(() => {
+        TestBed.createComponent(TestCmp);
+        TestBed.createComponent(TestCmp2);
+      }).not.toThrow();
+    });
+  });
+
+  describe('bootstrap', () => {
+    it('should throw when specified bootstrap component is not added to a module', () => {
+      @NgModule({bootstrap: [TestCmp, [TestCmp2]]})
+      class MyModule {
+      }
+
+      TestBed.configureTestingModule({imports: [MyModule]});
+
+      expect(() => {
+        TestBed.createComponent(TestCmp);
+        TestBed.createComponent(TestCmp2);
+      }).toThrowError(/not part of any NgModule/);
+    });
+
+    it('should not throw when specified bootstrap component is added to a module', () => {
+      @NgModule({declarations: [TestCmp, TestCmp2], bootstrap: [TestCmp, [TestCmp2]]})
+      class MyModule {
+      }
+
+      TestBed.configureTestingModule({imports: [MyModule]});
+
+      expect(() => {
+        TestBed.createComponent(TestCmp);
+        TestBed.createComponent(TestCmp2);
+      }).not.toThrow();
+    });
+  });
+
+});