fix(compiler): pipes used inside defer triggers not being picked up

packages/compiler-cli/test/compliance/test_cases/r3_view_compiler_deferred/GOLDEN_PARTIAL.js

@@ -517,7 +517,7 @@ MyApp.ɵcmp = i0.ɵɵngDeclareComponent({ minVersion: "17.0.0", version: "0.0.0-
     @defer (when isVisible() && (isReady | testPipe)) {
       Hello
     }
-  `, isInline: true });
+  `, isInline: true, dependencies: [{ kind: "pipe", type: TestPipe, name: "testPipe" }] });
 i0.ɵɵngDeclareClassMetadata({ minVersion: "12.0.0", version: "0.0.0-PLACEHOLDER", ngImport: i0, type: MyApp, decorators: [{
             type: Component,
             args: [{

packages/compiler-cli/test/ngtsc/ngtsc_spec.ts

@@ -9053,6 +9053,105 @@ function allTests(os: string) {
         });
       });
 
+      it('should detect pipe used in the `when` trigger as an eager dependency', () => {
+        env.write('test-pipe.ts', `
+          import { Pipe } from '@angular/core';
+
+          @Pipe({name: 'test', standalone: true})
+          export class TestPipe {
+            transform() {
+              return 1;
+            }
+          }
+        `);
+
+        env.write('/test.ts', `
+          import { Component } from '@angular/core';
+          import { TestPipe } from './test-pipe';
+
+          @Component({
+            selector: 'test-cmp',
+            standalone: true,
+            imports: [TestPipe],
+            template: '@defer (when 1 | test) { hello }',
+          })
+          export class TestCmp {
+          }
+        `);
+
+        env.driveMain();
+
+        const jsContents = env.getContents('test.js');
+
+        expect(jsContents).toContain('dependencies: [TestPipe]');
+      });
+
+      it('should detect pipe used in the `prefetch when` trigger as an eager dependency', () => {
+        env.write('test-pipe.ts', `
+          import { Pipe } from '@angular/core';
+
+          @Pipe({name: 'test', standalone: true})
+          export class TestPipe {
+            transform() {
+              return 1;
+            }
+          }
+        `);
+
+        env.write('/test.ts', `
+          import { Component } from '@angular/core';
+          import { TestPipe } from './test-pipe';
+
+          @Component({
+            selector: 'test-cmp',
+            standalone: true,
+            imports: [TestPipe],
+            template: '@defer (when 1 | test) { hello }',
+          })
+          export class TestCmp {
+          }
+        `);
+
+        env.driveMain();
+
+        const jsContents = env.getContents('test.js');
+
+        expect(jsContents).toContain('dependencies: [TestPipe]');
+      });
+
+      it('should detect pipe used both in a trigger and the deferred content as eager', () => {
+        env.write('test-pipe.ts', `
+          import { Pipe } from '@angular/core';
+
+          @Pipe({name: 'test', standalone: true})
+          export class TestPipe {
+            transform() {
+              return 1;
+            }
+          }
+        `);
+
+        env.write('/test.ts', `
+          import { Component } from '@angular/core';
+          import { TestPipe } from './test-pipe';
+
+          @Component({
+            selector: 'test-cmp',
+            standalone: true,
+            imports: [TestPipe],
+            template: '@defer (when 1 | test) { {{1 | test}} }',
+          })
+          export class TestCmp {
+          }
+        `);
+
+        env.driveMain();
+
+        const jsContents = env.getContents('test.js');
+
+        expect(jsContents).toContain('dependencies: [TestPipe]');
+      });
+
       describe('setClassMetadataAsync', () => {
         it('should generate setClassMetadataAsync for components with defer blocks', () => {
           env.write('cmp-a.ts', `

packages/compiler/src/render3/view/t2_binder.ts

@@ -8,7 +8,7 @@
 
 import {AST, BindingPipe, ImplicitReceiver, PropertyRead, PropertyWrite, RecursiveAstVisitor, SafePropertyRead} from '../../expression_parser/ast';
 import {SelectorMatcher} from '../../selector';
-import {BoundAttribute, BoundDeferredTrigger, BoundEvent, BoundText, Content, DeferredBlock, DeferredBlockError, DeferredBlockLoading, DeferredBlockPlaceholder, DeferredTrigger, Element, ForLoopBlock, ForLoopBlockEmpty, HoverDeferredTrigger, Icu, IfBlock, IfBlockBranch, InteractionDeferredTrigger, Node, Reference, SwitchBlock, SwitchBlockCase, Template, Text, TextAttribute, UnknownBlock, Variable, ViewportDeferredTrigger, Visitor} from '../r3_ast';
+import {BoundAttribute, BoundEvent, BoundText, Content, DeferredBlock, DeferredBlockError, DeferredBlockLoading, DeferredBlockPlaceholder, DeferredTrigger, Element, ForLoopBlock, ForLoopBlockEmpty, HoverDeferredTrigger, Icu, IfBlock, IfBlockBranch, InteractionDeferredTrigger, Node, Reference, SwitchBlock, SwitchBlockCase, Template, Text, TextAttribute, UnknownBlock, Variable, ViewportDeferredTrigger, Visitor} from '../r3_ast';
 
 import {BoundTarget, DirectiveMeta, ReferenceTarget, ScopedNode, Target, TargetBinder} from './t2_api';
 import {createCssSelector} from './template';
@@ -593,6 +593,7 @@ class TemplateBinder extends RecursiveAstVisitor implements Visitor {
   visitContent(content: Content) {}
   visitTextAttribute(attribute: TextAttribute) {}
   visitUnknownBlock(block: UnknownBlock) {}
+  visitDeferredTrigger(): void {}
   visitIcu(icu: Icu): void {
     Object.keys(icu.vars).forEach(key => icu.vars[key].visit(this));
     Object.keys(icu.placeholders).forEach(key => icu.placeholders[key].visit(this));
@@ -612,17 +613,13 @@ class TemplateBinder extends RecursiveAstVisitor implements Visitor {
     this.deferBlocks.add(deferred);
     this.ingestScopedNode(deferred);
 
+    deferred.triggers.when?.value.visit(this);
+    deferred.prefetchTriggers.when?.value.visit(this);
     deferred.placeholder && this.visitNode(deferred.placeholder);
     deferred.loading && this.visitNode(deferred.loading);
     deferred.error && this.visitNode(deferred.error);
   }
 
-  visitDeferredTrigger(trigger: DeferredTrigger): void {
-    if (trigger instanceof BoundDeferredTrigger) {
-      trigger.value.visit(this);
-    }
-  }
-
   visitDeferredBlockPlaceholder(block: DeferredBlockPlaceholder) {
     this.ingestScopedNode(block);
   }