refactor(core): replace Optional/SkipSelf deps with inject() flags (angular#63386)

This commit updates provider definitions that relied on the `deps` array
with `new Optional()` and `new SkipSelf()` to instead use the modern
`inject(..., { optional: true, skipSelf: true })` API.

Previously:
  deps: [[KeyValueDiffers, new SkipSelf(), new Optional()]]

Now:
  const parent = inject(KeyValueDiffers, { optional: true, skipSelf: true });

**Bundle size reduction**: `Optional` and `SkipSelf` are runtime values
created by `makeParamDecorator()`. Even in production builds, esbuild
and other bundlers must keep their factory code because they are
referenced with `new Optional()` / `new SkipSelf()`. With `inject()`,
those classes are no longer referenced, allowing them and the
`makeParamDecorator` scaffolding to be tree-shaken when unused.

As a result, production bundles can drop both `Optional`, `SkipSelf`, and
their supporting factory code when not used elsewhere, reducing code size
while keeping the same behavior.

PR Close angular#63386

Author: arturovt

packages/core/src/change_detection/differs/iterable_differs.ts

@@ -6,9 +6,9 @@
  * found in the LICENSE file at https://angular.dev/license
  */
 
+import {inject} from '../../di';
 import {ɵɵdefineInjectable} from '../../di/interface/defs';
 import {StaticProvider} from '../../di/interface/provider';
-import {Optional, SkipSelf} from '../../di/metadata';
 import {RuntimeError, RuntimeErrorCode} from '../../errors';
 import {DefaultIterableDifferFactory} from '../differs/default_iterable_differ';
 
@@ -233,14 +233,13 @@ export class IterableDiffers {
   static extend(factories: IterableDifferFactory[]): StaticProvider {
     return {
       provide: IterableDiffers,
-      useFactory: (parent: IterableDiffers | null) => {
+      useFactory: () => {
+        const parent = inject(IterableDiffers, {optional: true, skipSelf: true});
         // if parent is null, it means that we are in the root injector and we have just overridden
         // the default injection mechanism for IterableDiffers, in such a case just assume
         // `defaultIterableDiffersFactory`.
         return IterableDiffers.create(factories, parent || defaultIterableDiffersFactory());
       },
-      // Dependency technically isn't optional, but we can provide a better error message this way.
-      deps: [[IterableDiffers, new SkipSelf(), new Optional()]],
     };
   }
 

packages/core/src/change_detection/differs/keyvalue_differs.ts

@@ -6,7 +6,7 @@
  * found in the LICENSE file at https://angular.dev/license
  */
 
-import {Optional, SkipSelf, StaticProvider, ɵɵdefineInjectable} from '../../di';
+import {inject, Optional, SkipSelf, StaticProvider, ɵɵdefineInjectable} from '../../di';
 import {RuntimeError, RuntimeErrorCode} from '../../errors';
 
 import {DefaultKeyValueDifferFactory} from './default_keyvalue_differ';
@@ -166,14 +166,13 @@ export class KeyValueDiffers {
   static extend<S>(factories: KeyValueDifferFactory[]): StaticProvider {
     return {
       provide: KeyValueDiffers,
-      useFactory: (parent: KeyValueDiffers) => {
+      useFactory: () => {
+        const parent = inject(KeyValueDiffers, {optional: true, skipSelf: true});
         // if parent is null, it means that we are in the root injector and we have just overridden
         // the default injection mechanism for KeyValueDiffers, in such a case just assume
         // `defaultKeyValueDiffersFactory`.
         return KeyValueDiffers.create(factories, parent || defaultKeyValueDiffersFactory());
       },
-      // Dependency technically isn't optional, but we can provide a better error message this way.
-      deps: [[KeyValueDiffers, new SkipSelf(), new Optional()]],
     };
   }
 

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

@@ -58,6 +58,7 @@
       "shimStylesContent"
     ],
     "lazy": [
+      "DeferComponent",
       "AFTER_RENDER_SEQUENCES_TO_ADD",
       "ANIMATIONS_DISABLED",
       "APP_BOOTSTRAP_LISTENER",
@@ -753,8 +754,7 @@
       "wasLastNodeCreated",
       "writeDirectClass",
       "writeDirectStyle",
-      "writeToDirectiveInput",
-      "DeferComponent"
+      "writeToDirectiveInput"
     ]
   }
 }

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

@@ -198,8 +198,6 @@
       "ObjectUnsubscribedError",
       "Observable",
       "OperatorSubscriber",
-      "Optional",
-      "PARAMETERS",
       "PARENT",
       "PENDING",
       "PLATFORM_BROWSER_ID",
@@ -245,7 +243,6 @@
       "ShadowDomRenderer",
       "SharedStylesHost",
       "SimpleChange",
-      "SkipSelf",
       "StandaloneService",
       "StatusChangeEvent",
       "Subject",
@@ -385,7 +382,6 @@
       "assertDefined",
       "assertNotDestroyed",
       "assertPlatform",
-      "attachInjectFlag",
       "attachPatchData",
       "augmentRuntimeError",
       "baseElement",
@@ -789,8 +785,6 @@
       "lookupTokenUsingEmbeddedInjector",
       "lookupTokenUsingModuleInjector",
       "lookupTokenUsingNodeInjector",
-      "makeMetadataCtor",
-      "makeParamDecorator",
       "makeRecord",
       "makeValidatorsArray",
       "map",

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

@@ -194,8 +194,6 @@
       "ObjectUnsubscribedError",
       "Observable",
       "OperatorSubscriber",
-      "Optional",
-      "PARAMETERS",
       "PARENT",
       "PENDING",
       "PLATFORM_BROWSER_ID",
@@ -240,7 +238,6 @@
       "ShadowDomRenderer",
       "SharedStylesHost",
       "SimpleChange",
-      "SkipSelf",
       "StandaloneService",
       "StatusChangeEvent",
       "Subject",
@@ -389,7 +386,6 @@
       "assertDefined",
       "assertNotDestroyed",
       "assertPlatform",
-      "attachInjectFlag",
       "attachPatchData",
       "augmentRuntimeError",
       "baseElement",
@@ -790,8 +786,6 @@
       "lookupTokenUsingEmbeddedInjector",
       "lookupTokenUsingModuleInjector",
       "lookupTokenUsingNodeInjector",
-      "makeMetadataCtor",
-      "makeParamDecorator",
       "makeRecord",
       "makeValidatorsArray",
       "map",