refactor: ensure hammer migration properly sets up gesture config in app module

src/cdk/schematics/update-tool/index.ts

@@ -122,8 +122,8 @@ export function runMigrationRules<T>(
   if (ruleFailures.length) {
     ruleFailures.forEach(({filePath, message, position}) => {
       const normalizedFilePath = normalize(getProjectRelativePath(filePath));
-      const lineAndCharacter = `${position.line + 1}:${position.character + 1}`;
-      logger.warn(`${normalizedFilePath}@${lineAndCharacter} - ${message}`);
+      const lineAndCharacter = position ? `@${position.line + 1}:${position.character + 1}` : '';
+      logger.warn(`${normalizedFilePath}${lineAndCharacter} - ${message}`);
     });
   }
 

src/cdk/schematics/update-tool/migration-rule.ts

@@ -16,7 +16,7 @@ import {LineAndCharacter} from './utils/line-mappings';
 export interface MigrationFailure {
   filePath: string;
   message: string;
-  position: LineAndCharacter;
+  position?: LineAndCharacter;
 }
 
 export class MigrationRule<T> {

src/material/schematics/ng-update/test-cases/v9/hammer-migration-v9.spec.ts

@@ -536,6 +536,54 @@ describe('v9 HammerJS removal', () => {
         export class AppModule { }`);
     });
 
+    it('should add gesture config provider to app module if module is referenced through ' +
+        're-exports in bootstrap', async () => {
+      writeFile('/projects/cdk-testing/src/app/app.component.html', `
+        <span (pinch)="onPinch($event)"></span>
+      `);
+
+      writeFile('/projects/cdk-testing/src/main.ts', `
+        import 'hammerjs';
+        import { enableProdMode } from '@angular/core';
+        import { platformBrowserDynamic } from '@angular/platform-browser-dynamic';
+
+        import { AppModule } from './app/';
+        import { environment } from './environments/environment';
+
+        if (environment.production) {
+          enableProdMode();
+        }
+
+        platformBrowserDynamic().bootstrapModule(AppModule)
+          .catch(err => console.error(err));
+      `);
+
+      writeFile('/projects/cdk-testing/src/app/index.ts', `export * from './app.module';`);
+
+      await runMigration();
+
+      expect(tree.readContent('/projects/cdk-testing/src/main.ts')).toContain(`import 'hammerjs';`);
+      expect(tree.exists('/projects/cdk-testing/src/gesture-config.ts')).toBe(true);
+      expect(tree.readContent('/projects/cdk-testing/src/app/app.module.ts')).toContain(dedent`\
+        import { BrowserModule, HAMMER_GESTURE_CONFIG } from '@angular/platform-browser';
+        import { NgModule } from '@angular/core';
+
+        import { AppComponent } from './app.component';
+        import { GestureConfig } from "../gesture-config";
+
+        @NgModule({
+          declarations: [
+            AppComponent
+          ],
+          imports: [
+            BrowserModule
+          ],
+          providers: [{ provide: HAMMER_GESTURE_CONFIG, useClass: GestureConfig }],
+          bootstrap: [AppComponent]
+        })
+        export class AppModule { }`);
+    });
+
     it('should not add gesture config provider multiple times if already provided', async () => {
       writeFile('/projects/cdk-testing/src/app/app.component.html', `
         <span (pinch)="onPinch($event)"></span>

src/material/schematics/ng-update/upgrade-rules/hammer-gestures-v9/find-main-module.ts

@@ -0,0 +1,30 @@
+/**
+ * @license
+ * Copyright Google LLC All Rights Reserved.
+ *
+ * Use of this source code is governed by an MIT-style license that can be
+ * found in the LICENSE file at https://angular.io/license
+ */
+
+import * as ts from 'typescript';
+
+/**
+ * Finds the main Angular module within the specified source file. The first module
+ * that is part of the "bootstrapModule" expression is returned.
+ */
+export function findMainModuleExpression(mainSourceFile: ts.SourceFile): ts.Expression|null {
+  let foundModule: ts.Expression|null = null;
+  const visitNode = (node: ts.Node) => {
+    if (ts.isCallExpression(node) && node.arguments.length &&
+        ts.isPropertyAccessExpression(node.expression) && ts.isIdentifier(node.expression.name) &&
+        node.expression.name.text === 'bootstrapModule') {
+      foundModule = node.arguments[0]!;
+    } else {
+      ts.forEachChild(node, visitNode);
+    }
+  };
+
+  ts.forEachChild(mainSourceFile, visitNode);
+
+  return foundModule;
+}

src/material/schematics/ng-update/upgrade-rules/hammer-gestures-v9/hammer-gestures-rule.ts

@@ -28,7 +28,6 @@ import {
 } from '@schematics/angular/utility/ast-utils';
 import {InsertChange} from '@schematics/angular/utility/change';
 import {getWorkspace} from '@schematics/angular/utility/config';
-import {getAppModulePath} from '@schematics/angular/utility/ng-ast-utils';
 import {WorkspaceProject} from '@schematics/angular/utility/workspace-models';
 import chalk from 'chalk';
 import {readFileSync} from 'fs';
@@ -37,6 +36,7 @@ import * as ts from 'typescript';
 
 import {getProjectFromProgram} from './cli-workspace';
 import {findHammerScriptImportElements} from './find-hammer-script-tags';
+import {findMainModuleExpression} from './find-main-module';
 import {isHammerJsUsedInTemplate} from './hammer-template-check';
 import {getImportOfIdentifier, Import} from './identifier-imports';
 import {ImportManager} from './import-manager';
@@ -53,6 +53,9 @@ const HAMMER_MODULE_SPECIFIER = 'hammerjs';
 const CANNOT_REMOVE_REFERENCE_ERROR =
     `Cannot remove reference to "GestureConfig". Please remove manually.`;
 
+const CANNOT_SETUP_APP_MODULE_ERROR = `Could not setup HammerJS gesture in module. Please ` +
+  `manually ensure that the Hammer gesture config is set up.`;
+
 interface IdentifierReference {
   node: ts.Identifier;
   importData: Import;
@@ -198,21 +201,8 @@ export class HammerGesturesRule extends MigrationRule<null> {
     this._gestureConfigReferences.forEach(
         i => this._replaceGestureConfigReference(i, gestureConfigPath));
 
-    const appModulePath = getAppModulePath(this.tree, getProjectMainFile(project));
-    const sourceFile = this.program.getSourceFile(join(this.basePath, appModulePath));
-
-    if (!sourceFile) {
-      this.failures.push({
-        filePath: appModulePath,
-        message: `Could not setup HammerJS gesture in module. Please manually ensure that ` +
-            `the Hammer gesture config is set up.`,
-        position: {character: 0, line: 0}
-      });
-      return;
-    }
-
-    // Setup the gesture config provider in the project app module if not done.
-    this._setupGestureConfigProviderIfNeeded(sourceFile, appModulePath, gestureConfigPath);
+    // Setup the gesture config provider in the project app module if not done already.
+    this._setupGestureConfigInAppModule(project, gestureConfigPath);
   }
 
   /**
@@ -531,12 +521,38 @@ export class HammerGesturesRule extends MigrationRule<null> {
     });
   }
 
-  /**
-   * Sets up the Hammer gesture config provider in the given app module
-   * if needed.
-   */
-  private _setupGestureConfigProviderIfNeeded(
-      sourceFile: ts.SourceFile, appModulePath: string, configPath: string) {
+  /** Sets up the Hammer gesture config provider in the app module if needed. */
+  private _setupGestureConfigInAppModule(project: WorkspaceProject, configPath: string) {
+    const mainFilePath = join(this.basePath, getProjectMainFile(project));
+    const mainFile = this.program.getSourceFile(mainFilePath);
+    if (!mainFile) {
+      this.failures.push({
+        filePath: mainFilePath,
+        message: CANNOT_SETUP_APP_MODULE_ERROR,
+      });
+      return;
+    }
+
+    const appModuleExpr = findMainModuleExpression(mainFile);
+    if (!appModuleExpr) {
+      this.failures.push({
+        filePath: mainFilePath,
+        message: CANNOT_SETUP_APP_MODULE_ERROR,
+      });
+      return;
+    }
+
+    const appModuleSymbol = this._getDeclarationSymbolOfNode(unwrapExpression(appModuleExpr));
+    if (!appModuleSymbol || !appModuleSymbol.valueDeclaration) {
+      this.failures.push({
+        filePath: mainFilePath,
+        message: CANNOT_SETUP_APP_MODULE_ERROR,
+      });
+      return;
+    }
+
+    const sourceFile = appModuleSymbol.valueDeclaration.getSourceFile();
+    const relativePath = relative(this.basePath, sourceFile.fileName);
     const hammerConfigTokenExpr = this._importManager.addImportToSourceFile(
         sourceFile, HAMMER_CONFIG_TOKEN_NAME, HAMMER_CONFIG_TOKEN_MODULE);
     const gestureConfigExpr = this._importManager.addImportToSourceFile(
@@ -574,8 +590,8 @@ export class HammerGesturesRule extends MigrationRule<null> {
       return;
     }
 
-    const changeActions = addSymbolToNgModuleMetadata(
-        sourceFile, appModulePath, 'providers', this._printNode(newProviderNode, sourceFile), null);
+    const changeActions = addSymbolToNgModuleMetadata(sourceFile, relativePath, 'providers',
+        this._printNode(newProviderNode, sourceFile), null);
 
     changeActions.forEach(change => {
       if (change instanceof InsertChange) {
@@ -668,7 +684,7 @@ export class HammerGesturesRule extends MigrationRule<null> {
     }
 
     context.logger.info(chalk.yellow(
-        '  ⚠   The HammerJS v9 migration for Angular components is not able to migrate tests. ' +
+        '⚠ The HammerJS v9 migration for Angular components is not able to migrate tests. ' +
         'Please manually clean up tests in your project if they rely on HammerJS.'));
 
     // Clean global state once the workspace has been migrated. This is technically