From 19a2b783cfe2a992f78531ce3b1b510014b868bf Mon Sep 17 00:00:00 2001
From: Alex Rickabaugh <alx+alxhub@alxandria.net>
Date: Fri, 16 Nov 2018 17:01:56 +0100
Subject: [PATCH] feat(ivy): create a ModuleResolver to map module paths to
 files (#27697)

PR Close #27697
---
 .../compiler-cli/src/ngtsc/imports/index.ts   |  2 +-
 .../src/ngtsc/imports/src/resolver.ts         | 22 +++++++++++++++++++
 packages/compiler-cli/src/ngtsc/program.ts    |  4 +++-
 3 files changed, 26 insertions(+), 2 deletions(-)

diff --git a/packages/compiler-cli/src/ngtsc/imports/index.ts b/packages/compiler-cli/src/ngtsc/imports/index.ts
index 275566d131..386775da9d 100644
--- a/packages/compiler-cli/src/ngtsc/imports/index.ts
+++ b/packages/compiler-cli/src/ngtsc/imports/index.ts
@@ -8,4 +8,4 @@
 
 export {ImportRewriter, NoopImportRewriter, R3SymbolsImportRewriter, validateAndRewriteCoreSymbol} from './src/core';
 export {AbsoluteReference, ImportMode, NodeReference, Reference, ResolvedReference} from './src/references';
-export {ReferenceResolver, TsReferenceResolver} from './src/resolver';
+export {ModuleResolver, ReferenceResolver, TsReferenceResolver} from './src/resolver';
diff --git a/packages/compiler-cli/src/ngtsc/imports/src/resolver.ts b/packages/compiler-cli/src/ngtsc/imports/src/resolver.ts
index a4ec2bfecb..fbca9427ec 100644
--- a/packages/compiler-cli/src/ngtsc/imports/src/resolver.ts
+++ b/packages/compiler-cli/src/ngtsc/imports/src/resolver.ts
@@ -17,6 +17,28 @@ export interface ReferenceResolver {
       Reference<ts.Declaration>;
 }
 
+/**
+ * Used by `RouterEntryPointManager` and `NgModuleRouteAnalyzer` (which is in turn is used by
+ * `NgModuleDecoratorHandler`) for resolving the module source-files references in lazy-loaded
+ * routes (relative to the source-file containing the `NgModule` that provides the route
+ * definitions).
+ */
+export class ModuleResolver {
+  constructor(
+      private program: ts.Program, private compilerOptions: ts.CompilerOptions,
+      private host: ts.CompilerHost) {}
+
+  resolveModuleName(module: string, containingFile: ts.SourceFile): ts.SourceFile|null {
+    const resolved =
+        ts.resolveModuleName(module, containingFile.fileName, this.compilerOptions, this.host)
+            .resolvedModule;
+    if (resolved === undefined) {
+      return null;
+    }
+    return this.program.getSourceFile(resolved.resolvedFileName) || null;
+  }
+}
+
 export class TsReferenceResolver implements ReferenceResolver {
   private moduleExportsCache = new Map<string, Map<ts.Declaration, string>|null>();
 
diff --git a/packages/compiler-cli/src/ngtsc/program.ts b/packages/compiler-cli/src/ngtsc/program.ts
index 30926d17aa..fbeef8f77b 100644
--- a/packages/compiler-cli/src/ngtsc/program.ts
+++ b/packages/compiler-cli/src/ngtsc/program.ts
@@ -16,7 +16,7 @@ import {ComponentDecoratorHandler, DirectiveDecoratorHandler, InjectableDecorato
 import {BaseDefDecoratorHandler} from './annotations/src/base_def';
 import {ErrorCode, ngErrorCode} from './diagnostics';
 import {FlatIndexGenerator, ReferenceGraph, checkForPrivateExports, findFlatIndexEntryPoint} from './entry_point';
-import {ImportRewriter, NoopImportRewriter, R3SymbolsImportRewriter, Reference, TsReferenceResolver} from './imports';
+import {ImportRewriter, ModuleResolver, NoopImportRewriter, R3SymbolsImportRewriter, Reference, TsReferenceResolver} from './imports';
 import {PartialEvaluator} from './partial_evaluator';
 import {TypeScriptReflectionHost} from './reflection';
 import {HostResourceLoader} from './resource_loader';
@@ -45,6 +45,7 @@ export class NgtscProgram implements api.Program {
   private flatIndexGenerator: FlatIndexGenerator|null = null;
 
   private constructionDiagnostics: ts.Diagnostic[] = [];
+  private moduleResolver: ModuleResolver;
 
 
   constructor(
@@ -124,6 +125,7 @@ export class NgtscProgram implements api.Program {
         ts.createProgram(rootFiles, options, this.host, oldProgram && oldProgram.getTsProgram());
 
     this.entryPoint = entryPoint !== null ? this.tsProgram.getSourceFile(entryPoint) || null : null;
+    this.moduleResolver = new ModuleResolver(this.tsProgram, options, this.host);
   }
 
   getTsProgram(): ts.Program { return this.tsProgram; }