refactor(compiler): widen type of resolver function (#54908)

Updates the type of the resolver function to be any `Expression` since JIT may receive a function reference rather than a `ArrowFunctionExpr`.

PR Close #54908

packages/compiler-cli/linker/src/file_linker/partial_linkers/partial_component_linker_1.ts

@@ -259,7 +259,7 @@ export class PartialComponentLinkerVersion1<TStatement, TExpression> implements
 
   private createR3ComponentDeferMetadata(boundTarget: BoundTarget<any>): R3ComponentDeferMetadata {
     const deferredBlocks = boundTarget.getDeferBlocks();
-    const blocks = new Map<TmplAstDeferredBlock, o.ArrowFunctionExpr|null>();
+    const blocks = new Map<TmplAstDeferredBlock, o.Expression|null>();
 
     for (const block of deferredBlocks) {
       // TODO: leaving `deps` empty for now, to be implemented as one of the next steps.

packages/compiler-cli/src/ngtsc/annotations/component/src/handler.ts

@@ -1489,7 +1489,7 @@ export class ComponentDecoratorHandler implements
             'Internal error: deferPerBlockDependencies must be present when compiling in PerBlock mode');
       }
 
-      const blocks = new Map<TmplAstDeferredBlock, o.ArrowFunctionExpr|null>();
+      const blocks = new Map<TmplAstDeferredBlock, o.Expression|null>();
       for (const [block, dependencies] of perBlockDeps) {
         blocks.set(
             block,

packages/compiler/src/constant_pool.ts

@@ -198,9 +198,8 @@ export class ConstantPool {
 
   // TODO: useUniqueName(false) is necessary for naming compatibility with
   // TemplateDefinitionBuilder, but should be removed once Template Pipeline is the default.
-  getSharedFunctionReference(
-      fn: o.FunctionExpr|o.ArrowFunctionExpr, prefix: string,
-      useUniqueName: boolean = true): o.Expression {
+  getSharedFunctionReference(fn: o.Expression, prefix: string, useUniqueName: boolean = true):
+      o.Expression {
     const isArrow = fn instanceof o.ArrowFunctionExpr;
 
     for (const current of this.statements) {
@@ -212,14 +211,18 @@ export class ConstantPool {
 
       // Function declarations are saved as function statements
       // so we compare them directly to the passed-in function.
-      if (!isArrow && current instanceof o.DeclareFunctionStmt && fn.isEquivalent(current)) {
+      if (!isArrow && current instanceof o.DeclareFunctionStmt && fn instanceof o.FunctionExpr &&
+          fn.isEquivalent(current)) {
         return o.variable(current.name);
       }
     }
 
     // Otherwise declare the function.
     const name = useUniqueName ? this.uniqueName(prefix) : prefix;
-    this.statements.push(fn.toDeclStmt(name, o.StmtModifier.Final));
+    this.statements.push(
+        fn instanceof o.FunctionExpr ?
+            fn.toDeclStmt(name, o.StmtModifier.Final) :
+            new o.DeclareVarStmt(name, fn, o.INFERRED_TYPE, o.StmtModifier.Final, fn.sourceSpan));
     return o.variable(name);
   }
 

packages/compiler/src/jit_compiler_facade.ts

@@ -11,7 +11,7 @@ import {ConstantPool} from './constant_pool';
 import {ChangeDetectionStrategy, HostBinding, HostListener, Input, Output, ViewEncapsulation} from './core';
 import {compileInjectable} from './injectable_compiler_2';
 import {DEFAULT_INTERPOLATION_CONFIG, InterpolationConfig} from './ml_parser/defaults';
-import {ArrowFunctionExpr, DeclareVarStmt, Expression, literal, LiteralExpr, Statement, StmtModifier, WrappedNodeExpr} from './output/output_ast';
+import {DeclareVarStmt, Expression, literal, LiteralExpr, Statement, StmtModifier, WrappedNodeExpr} from './output/output_ast';
 import {JitEvaluator} from './output/output_jit';
 import {ParseError, ParseSourceSpan, r3JitTypeSourceSpan} from './parse_util';
 import {DeferredBlock} from './render3/r3_ast';
@@ -624,7 +624,7 @@ function createR3DependencyMetadata(
 
 function createR3ComponentDeferMetadata(boundTarget: BoundTarget<any>): R3ComponentDeferMetadata {
   const deferredBlocks = boundTarget.getDeferBlocks();
-  const blocks = new Map<DeferredBlock, ArrowFunctionExpr|null>();
+  const blocks = new Map<DeferredBlock, Expression|null>();
 
   for (const block of deferredBlocks) {
     // TODO: leaving dependency function empty in JIT mode for now,

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

@@ -296,10 +296,10 @@ export interface R3ComponentMetadata<DeclarationT extends R3TemplateDependency>
  */
 export type R3ComponentDeferMetadata = {
   mode: DeferBlockDepsEmitMode.PerBlock,
-  blocks: Map<t.DeferredBlock, o.ArrowFunctionExpr|null>,
+  blocks: Map<t.DeferredBlock, o.Expression|null>,
 }|{
   mode: DeferBlockDepsEmitMode.PerComponent,
-  dependenciesFn: o.ArrowFunctionExpr | null,
+  dependenciesFn: o.Expression | null,
 };
 
 /**

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

@@ -180,7 +180,7 @@ export function compileComponentFromMetadata(
       meta.defer.dependenciesFn !== null) {
     const fnName = `${templateTypeName}_DeferFn`;
     constantPool.statements.push(
-        meta.defer.dependenciesFn.toDeclStmt(fnName, o.StmtModifier.Final));
+        new o.DeclareVarStmt(fnName, meta.defer.dependenciesFn, undefined, o.StmtModifier.Final));
     allDeferrableDepsFn = o.variable(fnName);
   }
 

packages/compiler/src/template/pipeline/ir/src/ops/create.ts

@@ -836,7 +836,7 @@ export interface DeferOp extends Op<CreateOp>, ConsumesSlotOpTrait {
    * per deferred block or one for the entire template. This field contains the function that
    * belongs specifically to the current deferred block.
    */
-  ownResolverFn: o.ArrowFunctionExpr|null;
+  ownResolverFn: o.Expression|null;
 
   /**
    * After processing, the resolver function for the defer deps will be extracted to the constant
@@ -848,7 +848,7 @@ export interface DeferOp extends Op<CreateOp>, ConsumesSlotOpTrait {
 }
 
 export function createDeferOp(
-    xref: XrefId, main: XrefId, mainSlot: SlotHandle, ownResolverFn: o.ArrowFunctionExpr|null,
+    xref: XrefId, main: XrefId, mainSlot: SlotHandle, ownResolverFn: o.Expression|null,
     resolverFn: o.Expression|null, sourceSpan: ParseSourceSpan): DeferOp {
   return {
     kind: OpKind.Defer,

packages/compiler/src/template/pipeline/src/ingest.ts

@@ -447,7 +447,7 @@ function ingestDeferView(
 }
 
 function ingestDeferBlock(unit: ViewCompilationUnit, deferBlock: t.DeferredBlock): void {
-  let ownResolverFn: o.ArrowFunctionExpr|null = null;
+  let ownResolverFn: o.Expression|null = null;
 
   if (unit.job.deferMeta.mode === DeferBlockDepsEmitMode.PerBlock) {
     if (!unit.job.deferMeta.blocks.has(deferBlock)) {