fix(@ngtools/webpack): use a single module resolution cache

Author: alan-agius4

packages/ngtools/webpack/src/angular_compiler_plugin.ts

@@ -355,8 +355,6 @@ export class AngularCompilerPlugin {
       this._updateForkedTypeChecker(this._rootNames, this._getChangedCompilationFiles());
     }
 
-    // Use an identity function as all our paths are absolute already.
-    this._moduleResolutionCache = ts.createModuleResolutionCache(this._basePath, x => x);
     const oldTsProgram = this._getTsProgram();
 
     if (this._JitMode) {
@@ -721,6 +719,9 @@ export class AngularCompilerPlugin {
         );
       }
 
+      // Use an identity function as all our paths are absolute already.
+      this._moduleResolutionCache = ts.createModuleResolutionCache(this._basePath, x => x);
+
       // Create the webpack compiler host.
       const webpackCompilerHost = new WebpackCompilerHost(
         this._compilerOptions,
@@ -729,6 +730,7 @@ export class AngularCompilerPlugin {
         true,
         this._options.directTemplateLoading,
         ngccProcessor,
+        this._moduleResolutionCache,
       );
 
       // Create and set a new WebpackResourceLoader in AOT

packages/ngtools/webpack/src/compiler_host.ts

@@ -46,6 +46,7 @@ export class WebpackCompilerHost implements ts.CompilerHost {
     private readonly cacheSourceFiles: boolean,
     private readonly directTemplateLoading = false,
     private readonly ngccProcessor?: NgccProcessor,
+    private readonly moduleResolutionCache?: ts.ModuleResolutionCache,
   ) {
     this._syncHost = new virtualFs.SyncDelegateHost(host);
     this._memoryHost = new virtualFs.SyncDelegateHost(new virtualFs.SimpleMemoryHost());
@@ -405,6 +406,7 @@ export class WebpackCompilerHost implements ts.CompilerHost {
         workaroundResolve(containingFile),
         this._options,
         this,
+        this.moduleResolutionCache,
       );
 
       if (this._options.enableIvy && resolvedModule && this.ngccProcessor) {