refactor(core): support EnvironmentProviders types internally (#47669)

This commit modifies `R3Injector` and other code in Angular that deals with
providers, to handle `EnvironmentProviders` objects as well as normal
`Provider` types. There is no user-visible impact to this change, but it
prepares the core of the DI system for the introduction of
`EnvironmentProviders` as a public feature.

PR Close #47669

packages/core/src/di/provider_collection.ts

@@ -21,7 +21,7 @@ import {resolveForwardRef} from './forward_ref';
 import {ENVIRONMENT_INITIALIZER} from './initializer_token';
 import {ɵɵinject as inject} from './injector_compatibility';
 import {getInjectorDef, InjectorType, InjectorTypeWithProviders} from './interface/defs';
-import {ClassProvider, ConstructorProvider, EnvironmentProviders, ExistingProvider, FactoryProvider, ImportedNgModuleProviders, ModuleWithProviders, Provider, StaticClassProvider, TypeProvider, ValueProvider} from './interface/provider';
+import {ClassProvider, ConstructorProvider, EnvironmentProviders, ExistingProvider, FactoryProvider, ImportedNgModuleProviders, InternalEnvironmentProviders, isEnvironmentProviders, ModuleWithProviders, Provider, StaticClassProvider, TypeProvider, ValueProvider} from './interface/provider';
 import {INJECTOR_DEF_TYPES} from './internal_tokens';
 
 /**
@@ -128,7 +128,7 @@ function processInjectorTypesWithProviders(
     typesWithProviders: InjectorTypeWithProviders<unknown>[], providersOut: Provider[]): void {
   for (let i = 0; i < typesWithProviders.length; i++) {
     const {ngModule, providers} = typesWithProviders[i];
-    deepForEach(providers!, provider => {
+    deepForEachProvider(providers! as Array<Provider|InternalEnvironmentProviders>, provider => {
       ngDevMode && validateProvider(provider, providers || EMPTY_ARRAY, ngModule);
       providersOut.push(provider);
     });
@@ -261,12 +261,12 @@ export function walkProviderTree(
     }
 
     // Next, include providers listed on the definition itself.
-    const defProviders = injDef.providers;
+    const defProviders = injDef.providers as Array<SingleProvider|InternalEnvironmentProviders>;
     if (defProviders != null && !isDuplicate) {
       const injectorType = container as InjectorType<any>;
-      deepForEach(defProviders, provider => {
-        ngDevMode && validateProvider(provider, defProviders as SingleProvider[], injectorType);
-        providersOut.push(provider);
+      deepForEachProvider(defProviders, provider => {
+        ngDevMode && validateProvider(provider as SingleProvider, defProviders, injectorType);
+        providersOut.push(provider as SingleProvider);
       });
     }
   } else {
@@ -280,7 +280,8 @@ export function walkProviderTree(
 }
 
 function validateProvider(
-    provider: SingleProvider, providers: SingleProvider[], containerType: Type<unknown>): void {
+    provider: SingleProvider, providers: Array<SingleProvider|InternalEnvironmentProviders>,
+    containerType: Type<unknown>): void {
   if (isTypeProvider(provider) || isValueProvider(provider) || isFactoryProvider(provider) ||
       isExistingProvider(provider)) {
     return;
@@ -294,6 +295,21 @@ function validateProvider(
   }
 }
 
+function deepForEachProvider(
+    providers: Array<Provider|InternalEnvironmentProviders>,
+    fn: (provider: SingleProvider) => void): void {
+  for (let provider of providers) {
+    if (isEnvironmentProviders(provider)) {
+      provider = provider.ɵproviders;
+    }
+    if (Array.isArray(provider)) {
+      deepForEachProvider(provider, fn);
+    } else {
+      fn(provider);
+    }
+  }
+}
+
 export const USE_VALUE =
     getClosureSafeProperty<ValueProvider>({provide: String, useValue: getClosureSafeProperty});
 

packages/core/src/di/r3_injector.ts

@@ -27,7 +27,7 @@ import {catchInjectorError, convertToBitFlags, injectArgs, NG_TEMP_TOKEN_PATH, s
 import {INJECTOR} from './injector_token';
 import {getInheritedInjectableDef, getInjectableDef, InjectorType, ɵɵInjectableDeclaration} from './interface/defs';
 import {InjectFlags, InjectOptions} from './interface/injector';
-import {ClassProvider, ConstructorProvider, ImportedNgModuleProviders, Provider, StaticClassProvider} from './interface/provider';
+import {ClassProvider, ConstructorProvider, EnvironmentProviders, ImportedNgModuleProviders, InternalEnvironmentProviders, isEnvironmentProviders, Provider, StaticClassProvider} from './interface/provider';
 import {INJECTOR_DEF_TYPES} from './internal_tokens';
 import {NullInjector} from './null_injector';
 import {isExistingProvider, isFactoryProvider, isTypeProvider, isValueProvider, SingleProvider} from './provider_collection';
@@ -157,11 +157,14 @@ export class R3Injector extends EnvironmentInjector {
   private injectorDefTypes: Set<Type<unknown>>;
 
   constructor(
-      providers: Array<Provider|ImportedNgModuleProviders>, readonly parent: Injector,
-      readonly source: string|null, readonly scopes: Set<InjectorScope>) {
+      providers: Array<Provider|ImportedNgModuleProviders|EnvironmentProviders>,
+      readonly parent: Injector, readonly source: string|null,
+      readonly scopes: Set<InjectorScope>) {
     super();
     // Start off by creating Records for every provider.
-    forEachSingleProvider(providers, provider => this.processProvider(provider));
+    forEachSingleProvider(
+        providers as Array<Provider|ImportedNgModuleProviders|InternalEnvironmentProviders>,
+        provider => this.processProvider(provider));
 
     // Make sure the INJECTOR token provides this injector.
     this.records.set(INJECTOR, makeRecord(undefined, this));
@@ -460,7 +463,7 @@ function providerToRecord(provider: SingleProvider): Record<any> {
 export function providerToFactory(
     provider: SingleProvider, ngModuleType?: InjectorType<any>, providers?: any[]): () => any {
   let factory: (() => any)|undefined = undefined;
-  if (ngDevMode && isImportedNgModuleProviders(provider)) {
+  if (ngDevMode && (isImportedNgModuleProviders(provider) || isEnvironmentProviders(provider))) {
     throwInvalidProviderError(undefined, providers, provider);
   }
 
@@ -517,19 +520,20 @@ function couldBeInjectableType(value: any): value is ProviderToken<any> {
 
 function isImportedNgModuleProviders(provider: Provider|ImportedNgModuleProviders):
     provider is ImportedNgModuleProviders {
-  return !!(provider as ImportedNgModuleProviders).ɵproviders;
+  return provider && !!(provider as ImportedNgModuleProviders).ɵproviders;
 }
 
 function forEachSingleProvider(
-    providers: Array<Provider|ImportedNgModuleProviders>,
+    providers: Array<Provider|ImportedNgModuleProviders|InternalEnvironmentProviders>,
     fn: (provider: SingleProvider) => void): void {
   for (const provider of providers) {
     if (Array.isArray(provider)) {
       forEachSingleProvider(provider, fn);
-    } else if (isImportedNgModuleProviders(provider)) {
+    } else if (
+        provider && (isImportedNgModuleProviders(provider) || isEnvironmentProviders(provider))) {
       forEachSingleProvider(provider.ɵproviders, fn);
     } else {
-      fn(provider);
+      fn(provider as SingleProvider);
     }
   }
 }

packages/core/src/render3/errors_di.ts

@@ -6,7 +6,7 @@
  * found in the LICENSE file at https://angular.io/license
  */
 
-import {ImportedNgModuleProviders} from '../di/interface/provider';
+import {isEnvironmentProviders} from '../di/interface/provider';
 import {RuntimeError, RuntimeErrorCode} from '../errors';
 import {Type} from '../interface/type';
 import {stringify} from '../util/stringify';
@@ -33,10 +33,16 @@ export function throwInvalidProviderError(
     throw new Error(`Invalid provider for the NgModule '${
         stringify(ngModuleType)}' - only instances of Provider and Type are allowed, got: [${
         providerDetail.join(', ')}]`);
-  } else if ((provider as ImportedNgModuleProviders).ɵproviders) {
-    throw new RuntimeError(
-        RuntimeErrorCode.PROVIDER_IN_WRONG_CONTEXT,
-        `Invalid providers from 'importProvidersFrom' present in a non-environment injector. 'importProvidersFrom' can't be used for component providers.`);
+  } else if (isEnvironmentProviders(provider)) {
+    if (provider.ɵfromNgModule) {
+      throw new RuntimeError(
+          RuntimeErrorCode.PROVIDER_IN_WRONG_CONTEXT,
+          `Invalid providers from 'importProvidersFrom' present in a non-environment injector. 'importProvidersFrom' can't be used for component providers.`);
+    } else {
+      throw new RuntimeError(
+          RuntimeErrorCode.PROVIDER_IN_WRONG_CONTEXT,
+          `Invalid providers present in a non-environment injector. 'EnvironmentProviders' can't be used for component providers.`);
+    }
   } else {
     throw new Error('Invalid provider');
   }

packages/core/test/bundling/animations/bundle.golden_symbols.json

@@ -710,6 +710,9 @@
   {
     "name": "deepForEach"
   },
+  {
+    "name": "deepForEachProvider"
+  },
   {
     "name": "detachMovedView"
   },
@@ -1001,6 +1004,9 @@
   {
     "name": "isElementNode"
   },
+  {
+    "name": "isEnvironmentProviders"
+  },
   {
     "name": "isFunction"
   },

packages/core/test/bundling/cyclic_import/bundle.golden_symbols.json

@@ -497,6 +497,9 @@
   {
     "name": "deepForEach"
   },
+  {
+    "name": "deepForEachProvider"
+  },
   {
     "name": "detachMovedView"
   },
@@ -749,6 +752,9 @@
   {
     "name": "isCurrentTNodeParent"
   },
+  {
+    "name": "isEnvironmentProviders"
+  },
   {
     "name": "isFunction"
   },

packages/core/test/bundling/forms_reactive/bundle.golden_symbols.json

@@ -722,6 +722,9 @@
   {
     "name": "deepForEach"
   },
+  {
+    "name": "deepForEachProvider"
+  },
   {
     "name": "defaultIterableDiffersFactory"
   },
@@ -1097,6 +1100,9 @@
   {
     "name": "isEmptyInputValue"
   },
+  {
+    "name": "isEnvironmentProviders"
+  },
   {
     "name": "isFormControlState"
   },

packages/core/test/bundling/forms_template_driven/bundle.golden_symbols.json

@@ -692,6 +692,9 @@
   {
     "name": "deepForEach"
   },
+  {
+    "name": "deepForEachProvider"
+  },
   {
     "name": "defaultIterableDiffersFactory"
   },
@@ -1055,6 +1058,9 @@
   {
     "name": "isDirectiveHost"
   },
+  {
+    "name": "isEnvironmentProviders"
+  },
   {
     "name": "isFormControlState"
   },

packages/core/test/bundling/hello_world/bundle.golden_symbols.json

@@ -359,6 +359,9 @@
   {
     "name": "deepForEach"
   },
+  {
+    "name": "deepForEachProvider"
+  },
   {
     "name": "detachMovedView"
   },
@@ -557,6 +560,9 @@
   {
     "name": "isComponentDef"
   },
+  {
+    "name": "isEnvironmentProviders"
+  },
   {
     "name": "isFunction"
   },

packages/core/test/bundling/injection/bundle.golden_symbols.json

@@ -83,6 +83,9 @@
   {
     "name": "deepForEach"
   },
+  {
+    "name": "deepForEachProvider"
+  },
   {
     "name": "forEachSingleProvider"
   },
@@ -122,6 +125,9 @@
   {
     "name": "internalImportProvidersFrom"
   },
+  {
+    "name": "isEnvironmentProviders"
+  },
   {
     "name": "isImportedNgModuleProviders"
   },

packages/core/test/bundling/router/bundle.golden_symbols.json

@@ -884,6 +884,9 @@
   {
     "name": "deepForEach"
   },
+  {
+    "name": "deepForEachProvider"
+  },
   {
     "name": "defaultErrorFactory"
   },
@@ -1340,6 +1343,9 @@
   {
     "name": "isEmptyError"
   },
+  {
+    "name": "isEnvironmentProviders"
+  },
   {
     "name": "isFunction"
   },

packages/core/test/bundling/standalone_bootstrap/bundle.golden_symbols.json

@@ -428,6 +428,9 @@
   {
     "name": "deepForEach"
   },
+  {
+    "name": "deepForEachProvider"
+  },
   {
     "name": "detachMovedView"
   },
@@ -641,6 +644,9 @@
   {
     "name": "isComponentDef"
   },
+  {
+    "name": "isEnvironmentProviders"
+  },
   {
     "name": "isFunction"
   },

packages/core/test/bundling/todo/bundle.golden_symbols.json

@@ -602,6 +602,9 @@
   {
     "name": "deepForEach"
   },
+  {
+    "name": "deepForEachProvider"
+  },
   {
     "name": "defaultIterableDiffersFactory"
   },
@@ -926,6 +929,9 @@
   {
     "name": "isDirectiveHost"
   },
+  {
+    "name": "isEnvironmentProviders"
+  },
   {
     "name": "isFunction"
   },

packages/core/testing/src/test_bed_compiler.ts

@@ -7,7 +7,7 @@
  */
 
 import {ResourceLoader} from '@angular/compiler';
-import {ApplicationInitStatus, Compiler, COMPILER_OPTIONS, Component, Directive, Injector, InjectorType, LOCALE_ID, ModuleWithComponentFactories, ModuleWithProviders, NgModule, NgModuleFactory, NgZone, Pipe, PlatformRef, Provider, resolveForwardRef, Type, ɵcompileComponent as compileComponent, ɵcompileDirective as compileDirective, ɵcompileNgModuleDefs as compileNgModuleDefs, ɵcompilePipe as compilePipe, ɵDEFAULT_LOCALE_ID as DEFAULT_LOCALE_ID, ɵDirectiveDef as DirectiveDef, ɵgetInjectableDef as getInjectableDef, ɵNG_COMP_DEF as NG_COMP_DEF, ɵNG_DIR_DEF as NG_DIR_DEF, ɵNG_INJ_DEF as NG_INJ_DEF, ɵNG_MOD_DEF as NG_MOD_DEF, ɵNG_PIPE_DEF as NG_PIPE_DEF, ɵNgModuleFactory as R3NgModuleFactory, ɵNgModuleTransitiveScopes as NgModuleTransitiveScopes, ɵNgModuleType as NgModuleType, ɵpatchComponentDefWithScope as patchComponentDefWithScope, ɵRender3ComponentFactory as ComponentFactory, ɵRender3NgModuleRef as NgModuleRef, ɵsetLocaleId as setLocaleId, ɵtransitiveScopesFor as transitiveScopesFor, ɵɵInjectableDeclaration as InjectableDeclaration} from '@angular/core';
+import {ApplicationInitStatus, Compiler, COMPILER_OPTIONS, Component, Directive, Injector, InjectorType, LOCALE_ID, ModuleWithComponentFactories, ModuleWithProviders, NgModule, NgModuleFactory, NgZone, Pipe, PlatformRef, Provider, resolveForwardRef, Type, ɵcompileComponent as compileComponent, ɵcompileDirective as compileDirective, ɵcompileNgModuleDefs as compileNgModuleDefs, ɵcompilePipe as compilePipe, ɵDEFAULT_LOCALE_ID as DEFAULT_LOCALE_ID, ɵDirectiveDef as DirectiveDef, ɵgetInjectableDef as getInjectableDef, ɵInternalEnvironmentProviders as InternalEnvironmentProviders, ɵisEnvironmentProviders as isEnvironmentProviders, ɵNG_COMP_DEF as NG_COMP_DEF, ɵNG_DIR_DEF as NG_DIR_DEF, ɵNG_INJ_DEF as NG_INJ_DEF, ɵNG_MOD_DEF as NG_MOD_DEF, ɵNG_PIPE_DEF as NG_PIPE_DEF, ɵNgModuleFactory as R3NgModuleFactory, ɵNgModuleTransitiveScopes as NgModuleTransitiveScopes, ɵNgModuleType as NgModuleType, ɵpatchComponentDefWithScope as patchComponentDefWithScope, ɵRender3ComponentFactory as ComponentFactory, ɵRender3NgModuleRef as NgModuleRef, ɵsetLocaleId as setLocaleId, ɵtransitiveScopesFor as transitiveScopesFor, ɵɵInjectableDeclaration as InjectableDeclaration} from '@angular/core';
 
 import {clearResolutionOfComponentResourcesQueue, isComponentDefPendingResolution, resolveComponentResources, restoreComponentResolutionQueue} from '../../src/metadata/resource_loading';
 import {ComponentDef, ComponentType} from '../../src/render3';
@@ -470,7 +470,7 @@ export class TestBedCompiler {
         this.applyProviderOverridesInScope(dependency);
       }
     } else {
-      const providers = [
+      const providers: Array<Provider|InternalEnvironmentProviders> = [
         ...injectorDef.providers,
         ...(this.providerOverridesByModule.get(type as InjectorType<any>) || [])
       ];
@@ -496,7 +496,8 @@ export class TestBedCompiler {
             fieldName: 'providers',
             originalValue: importedModule.providers
           });
-          importedModule.providers = this.getOverriddenProviders(importedModule.providers);
+          importedModule.providers = this.getOverriddenProviders(
+              importedModule.providers as Array<Provider|InternalEnvironmentProviders>);
         }
       }
     }
@@ -797,21 +798,23 @@ export class TestBedCompiler {
     return this.providerOverridesByToken.get(token) || null;
   }
 
-  private getProviderOverrides(providers?: Provider[]): Provider[] {
+  private getProviderOverrides(providers?: Array<Provider|InternalEnvironmentProviders>):
+      Provider[] {
     if (!providers || !providers.length || this.providerOverridesByToken.size === 0) return [];
-    // There are two flattening operations here. The inner flatten() operates on the metadata's
-    // providers and applies a mapping function which retrieves overrides for each incoming
-    // provider. The outer flatten() then flattens the produced overrides array. If this is not
-    // done, the array can contain other empty arrays (e.g. `[[], []]`) which leak into the
+    // There are two flattening operations here. The inner flattenProviders() operates on the
+    // metadata's providers and applies a mapping function which retrieves overrides for each
+    // incoming provider. The outer flatten() then flattens the produced overrides array. If this is
+    // not done, the array can contain other empty arrays (e.g. `[[], []]`) which leak into the
     // providers array and contaminate any error messages that might be generated.
-    return flatten(flatten(
+    return flatten(flattenProviders(
         providers, (provider: Provider) => this.getSingleProviderOverrides(provider) || []));
   }
 
-  private getOverriddenProviders(providers?: Provider[]): Provider[] {
+  private getOverriddenProviders(providers?: Array<Provider|InternalEnvironmentProviders>):
+      Provider[] {
     if (!providers || !providers.length || this.providerOverridesByToken.size === 0) return [];
 
-    const flattenedProviders = flatten<Provider[]>(providers);
+    const flattenedProviders = flattenProviders(providers);
     const overrides = this.getProviderOverrides(flattenedProviders);
     const overriddenProviders = [...flattenedProviders, ...overrides];
     const final: Provider[] = [];
@@ -838,7 +841,7 @@ export class TestBedCompiler {
     return final;
   }
 
-  private hasProviderOverrides(providers?: Provider[]): boolean {
+  private hasProviderOverrides(providers?: Array<Provider|InternalEnvironmentProviders>): boolean {
     return this.getProviderOverrides(providers).length > 0;
   }
 
@@ -887,18 +890,42 @@ function maybeUnwrapFn<T>(maybeFn: (() => T)|T): T {
   return maybeFn instanceof Function ? maybeFn() : maybeFn;
 }
 
-function flatten<T>(values: any[], mapFn?: (value: T) => any): T[] {
+function flatten<T>(values: any[]): T[] {
   const out: T[] = [];
   values.forEach(value => {
     if (Array.isArray(value)) {
-      out.push(...flatten<T>(value, mapFn));
+      out.push(...flatten<T>(value));
     } else {
-      out.push(mapFn ? mapFn(value) : value);
+      out.push(value);
     }
   });
   return out;
 }
 
+function identityFn<T>(value: T): T {
+  return value;
+}
+
+function flattenProviders<T>(
+    providers: Array<Provider|InternalEnvironmentProviders>, mapFn: (provider: Provider) => T): T[];
+function flattenProviders(providers: Array<Provider|InternalEnvironmentProviders>): Provider[];
+function flattenProviders(
+    providers: Array<Provider|InternalEnvironmentProviders>,
+    mapFn: (provider: Provider) => any = identityFn): any[] {
+  const out: any[] = [];
+  for (let provider of providers) {
+    if (isEnvironmentProviders(provider)) {
+      provider = provider.ɵproviders;
+    }
+    if (Array.isArray(provider)) {
+      out.push(...flattenProviders(provider, mapFn));
+    } else {
+      out.push(mapFn(provider));
+    }
+  }
+  return out;
+}
+
 function getProviderField(provider: Provider, field: string) {
   return provider && typeof provider === 'object' && (provider as any)[field];
 }