fix(ivy): use ReflectionHost in AbsoluteModuleStrategy (angular#30200)

The AbsoluteModuleStrategy in ngtsc assumed that the source code is
formatted as TypeScript with regards to module exports.

In ngcc this is not always the case, so this commit changes
`AbsoluteModuleStrategy` so that it relies upon a `ReflectionHost`  to
compute the exports of a module.

PR Close angular#30200

Author: petebacondarwin

packages/compiler-cli/ngcc/src/analysis/decoration_analyzer.ts

@@ -70,7 +70,8 @@ export class DecorationAnalyzer {
   fullMetaReader = new CompoundMetadataReader([this.metaRegistry, this.dtsMetaReader]);
   refEmitter = new ReferenceEmitter([
     new LocalIdentifierStrategy(),
-    new AbsoluteModuleStrategy(this.program, this.typeChecker, this.options, this.host),
+    new AbsoluteModuleStrategy(
+        this.program, this.typeChecker, this.options, this.host, this.reflectionHost),
     // TODO(alxhub): there's no reason why ngcc needs the "logical file system" logic here, as ngcc
     // projects only ever have one rootDir. Instead, ngcc should just switch its emitted import
     // based on whether a bestGuessOwningModule is present in the Reference.

packages/compiler-cli/src/ngtsc/imports/src/emitter.ts

@@ -11,11 +11,13 @@ import {ExternalReference} from '@angular/compiler/src/compiler';
 import * as ts from 'typescript';
 
 import {LogicalFileSystem, LogicalProjectPath} from '../../path';
+import {ReflectionHost} from '../../reflection';
 import {getSourceFile, isDeclaration, nodeNameForError, resolveModuleName} from '../../util/src/typescript';
 
 import {findExportedNameOfNode} from './find_export';
 import {ImportMode, Reference} from './references';
 
+
 /**
  * A host which supports an operation to convert a file name into a module name.
  *
@@ -115,8 +117,9 @@ export class AbsoluteModuleStrategy implements ReferenceEmitStrategy {
   private moduleExportsCache = new Map<string, Map<ts.Declaration, string>|null>();
 
   constructor(
-      private program: ts.Program, private checker: ts.TypeChecker,
-      private options: ts.CompilerOptions, private host: ts.CompilerHost) {}
+      protected program: ts.Program, protected checker: ts.TypeChecker,
+      protected options: ts.CompilerOptions, protected host: ts.CompilerHost,
+      private reflectionHost: ReflectionHost) {}
 
   emit(ref: Reference<ts.Node>, context: ts.SourceFile, importMode: ImportMode): Expression|null {
     if (ref.bestGuessOwningModule === null) {
@@ -159,7 +162,7 @@ export class AbsoluteModuleStrategy implements ReferenceEmitStrategy {
     return this.moduleExportsCache.get(moduleName) !;
   }
 
-  private enumerateExportsOfModule(specifier: string, fromFile: string):
+  protected enumerateExportsOfModule(specifier: string, fromFile: string):
       Map<ts.Declaration, string>|null {
     // First, resolve the module specifier to its entry point, and get the ts.Symbol for it.
     const resolvedModule = resolveModuleName(specifier, fromFile, this.options, this.host);
@@ -172,34 +175,12 @@ export class AbsoluteModuleStrategy implements ReferenceEmitStrategy {
       return null;
     }
 
-    const entryPointSymbol = this.checker.getSymbolAtLocation(entryPointFile);
-    if (entryPointSymbol === undefined) {
+    const exports = this.reflectionHost.getExportsOfModule(entryPointFile);
+    if (exports === null) {
       return null;
     }
-
-    // Next, build a Map of all the ts.Declarations exported via the specifier and their exported
-    // names.
     const exportMap = new Map<ts.Declaration, string>();
-
-    const exports = this.checker.getExportsOfModule(entryPointSymbol);
-    for (const expSymbol of exports) {
-      // Resolve export symbols to their actual declarations.
-      const declSymbol = expSymbol.flags & ts.SymbolFlags.Alias ?
-          this.checker.getAliasedSymbol(expSymbol) :
-          expSymbol;
-
-      // At this point the valueDeclaration of the symbol should be defined.
-      const decl = declSymbol.valueDeclaration;
-      if (decl === undefined) {
-        continue;
-      }
-
-      // Prefer importing the symbol via its declared name, but take any export of it otherwise.
-      if (declSymbol.name === expSymbol.name || !exportMap.has(decl)) {
-        exportMap.set(decl, expSymbol.name);
-      }
-    }
-
+    exports.forEach((declaration, name) => { exportMap.set(declaration.node, name); });
     return exportMap;
   }
 }

packages/compiler-cli/src/ngtsc/program.ts

@@ -438,7 +438,8 @@ export class NgtscProgram implements api.Program {
         // First, try to use local identifiers if available.
         new LocalIdentifierStrategy(),
         // Next, attempt to use an absolute import.
-        new AbsoluteModuleStrategy(this.tsProgram, checker, this.options, this.host),
+        new AbsoluteModuleStrategy(
+            this.tsProgram, checker, this.options, this.host, this.reflector),
         // Finally, check if the reference is being written into a file within the project's logical
         // file system, and use a relative import if so. If this fails, ReferenceEmitter will throw
         // an error.

packages/compiler-cli/src/ngtsc/typecheck/test/type_constructor_spec.ts

@@ -10,7 +10,7 @@ import * as ts from 'typescript';
 
 import {AbsoluteModuleStrategy, LocalIdentifierStrategy, LogicalProjectStrategy, Reference, ReferenceEmitter} from '../../imports';
 import {AbsoluteFsPath, LogicalFileSystem} from '../../path';
-import {isNamedClassDeclaration} from '../../reflection';
+import {TypeScriptReflectionHost, isNamedClassDeclaration} from '../../reflection';
 import {getDeclaration, makeProgram} from '../../testing/in_memory_typescript';
 import {getRootDirs} from '../../util/src/typescript';
 import {TypeCheckingConfig} from '../src/api';
@@ -54,7 +54,8 @@ TestClass.ngTypeCtor({value: 'test'});
       const logicalFs = new LogicalFileSystem(getRootDirs(host, options));
       const emitter = new ReferenceEmitter([
         new LocalIdentifierStrategy(),
-        new AbsoluteModuleStrategy(program, checker, options, host),
+        new AbsoluteModuleStrategy(
+            program, checker, options, host, new TypeScriptReflectionHost(checker)),
         new LogicalProjectStrategy(checker, logicalFs),
       ]);
       const ctx = new TypeCheckContext(
@@ -84,7 +85,8 @@ TestClass.ngTypeCtor({value: 'test'});
       const logicalFs = new LogicalFileSystem(getRootDirs(host, options));
       const emitter = new ReferenceEmitter([
         new LocalIdentifierStrategy(),
-        new AbsoluteModuleStrategy(program, checker, options, host),
+        new AbsoluteModuleStrategy(
+            program, checker, options, host, new TypeScriptReflectionHost(checker)),
         new LogicalProjectStrategy(checker, logicalFs),
       ]);
       const ctx = new TypeCheckContext(