angular
diff --git a/‎packages/core/schematics/migrations/renderer-to-renderer2/index.ts‎
Lines changed: 19 additions & 5 deletions b/‎packages/core/schematics/migrations/renderer-to-renderer2/index.ts‎
Lines changed: 19 additions & 5 deletions
diff --git a/‎packages/core/schematics/test/renderer_to_renderer2_migration_spec.ts‎
Lines changed: 0 additions & 1 deletion b/‎packages/core/schematics/test/renderer_to_renderer2_migration_spec.ts‎
Lines changed: 0 additions & 1 deletion
diff --git a/‎packages/core/schematics/utils/typescript/compiler_host.ts‎
Lines changed: 5 additions & 2 deletions b/‎packages/core/schematics/utils/typescript/compiler_host.ts‎
Lines changed: 5 additions & 2 deletions
@@ -18,18 +18,17 @@ import {HelperFunction, getHelper} from './helpers';
 import {migrateExpression, replaceImport} from './migration';
 import {findCoreImport, findRendererReferences} from './util';
 
-
+const MODULE_AUGMENTATION_FILENAME = 'ɵɵRENDERER_MIGRATION_CORE_AUGMENTATION.d.ts';
 
 /**
  * Migration that switches from `Renderer` to `Renderer2`. More information on how it works:
  * https://hackmd.angular.io/UTzUZTnPRA-cSa_4mHyfYw
  */
 export default function(): Rule {
-  return (tree: Tree, context: SchematicContext) => {
+  return (tree: Tree) => {
     const {buildPaths, testPaths} = getProjectTsConfigPaths(tree);
     const basePath = process.cwd();
     const allPaths = [...buildPaths, ...testPaths];
-    const logger = context.logger;
 
     if (!allPaths.length) {
       throw new SchematicsException(
@@ -44,8 +43,23 @@ export default function(): Rule {
 
 function runRendererToRenderer2Migration(tree: Tree, tsconfigPath: string, basePath: string) {
   const parsed = parseTsconfigFile(tsconfigPath, dirname(tsconfigPath));
-  const host = createMigrationCompilerHost(tree, parsed.options, basePath);
-  const program = ts.createProgram(parsed.fileNames, parsed.options, host);
+  const host = createMigrationCompilerHost(tree, parsed.options, basePath, fileName => {
+    // In case the module augmentation file has been requested, we return a source file that
+    // augments "@angular/core" to include a named export called "Renderer". This ensures that
+    // we can rely on the type checker for this migration in v9 where "Renderer" has been removed.
+    if (fileName === MODULE_AUGMENTATION_FILENAME) {
+      return `
+        import '@angular/core';
+        declare module "@angular/core" {
+          class Renderer {}
+        }
+      `;
+    }
+    return null;
+  });
+
+  const program =
+      ts.createProgram(parsed.fileNames.concat(MODULE_AUGMENTATION_FILENAME), parsed.options, host);
   const typeChecker = program.getTypeChecker();
   const printer = ts.createPrinter();
   const sourceFiles = program.getSourceFiles().filter(
 
@@ -35,7 +35,6 @@ describe('Renderer to Renderer2 migration', () => {
     }));
     // We need to declare the Angular symbols we're testing for, otherwise type checking won't work.
     writeFile('/node_modules/@angular/core/index.d.ts', `
-      export declare abstract class Renderer {}
       export declare function forwardRef(fn: () => any): any {}
     `);
 
 
@@ -10,15 +10,18 @@ import {relative} from 'path';
 import * as ts from 'typescript';
 
 export function createMigrationCompilerHost(
-    tree: Tree, options: ts.CompilerOptions, basePath: string): ts.CompilerHost {
+    tree: Tree, options: ts.CompilerOptions, basePath: string,
+    fakeRead?: (fileName: string) => string | null): ts.CompilerHost {
   const host = ts.createCompilerHost(options, true);
 
   // We need to overwrite the host "readFile" method, as we want the TypeScript
   // program to be based on the file contents in the virtual file tree. Otherwise
   // if we run multiple migrations we might have intersecting changes and
   // source files.
   host.readFile = fileName => {
-    const buffer = tree.read(relative(basePath, fileName));
+    const treeRelativePath = relative(basePath, fileName);
+    const fakeOutput = fakeRead ? fakeRead(treeRelativePath) : null;
+    const buffer = fakeOutput === null ? tree.read(treeRelativePath) : fakeOutput;
     // Strip BOM as otherwise TSC methods (Ex: getWidth) will return an offset which
     // which breaks the CLI UpdateRecorder.
     // See: https://github.com/angular/angular/pull/30719