feat(router): add migration to update calls to navigateByUrl and createUrlTree with invalid parameters (#38825)

In #38227 the signatures of `navigateByUrl` and `createUrlTree` were updated to exclude unsupported
properties from their `extras` parameter. This migration looks for the relevant method calls that
pass in an `extras` parameter and drops the unsupported properties.

**Before:**
```
this._router.navigateByUrl('/', {skipLocationChange: false, fragment: 'foo'});
```

**After:**
```
this._router.navigateByUrl('/', {
  /* Removed unsupported properties by Angular migration: fragment. */
  skipLocationChange: false
});
```

These changes also move the method call detection logic out of the `Renderer2` migration and into
a common place so that it can be reused in other migrations.

PR Close #38825

packages/core/schematics/BUILD.bazel

@@ -14,6 +14,7 @@ pkg_npm(
         "//packages/core/schematics/migrations/missing-injectable",
         "//packages/core/schematics/migrations/module-with-providers",
         "//packages/core/schematics/migrations/move-document",
+        "//packages/core/schematics/migrations/navigation-extras-omissions",
         "//packages/core/schematics/migrations/renderer-to-renderer2",
         "//packages/core/schematics/migrations/static-queries",
         "//packages/core/schematics/migrations/template-var-assignment",

packages/core/schematics/migrations.json

@@ -44,6 +44,11 @@
       "version": "10.0.0-beta",
       "description": "Undecorated classes with Angular features migration. In version 10, classes that use Angular features and do not have an Angular decorator are no longer supported. Read more about this here: https://v10.angular.io/guide/migration-undecorated-classes",
       "factory": "./migrations/undecorated-classes-with-decorated-fields/index"
+    },
+    "migration-v11-navigation-extras-omissions": {
+      "version": "11.0.0-beta",
+      "description": "NavigationExtras omissions migration. In version 11, some unsupported properties were omitted from the `extras` parameter of the `Router.navigateByUrl` and `Router.createUrlTree` methods.",
+      "factory": "./migrations/navigation-extras-omissions/index"
     }
   }
 }

packages/core/schematics/migrations/google3/BUILD.bazel

@@ -9,6 +9,7 @@ ts_library(
         "//packages/core/schematics/migrations/dynamic-queries",
         "//packages/core/schematics/migrations/missing-injectable",
         "//packages/core/schematics/migrations/missing-injectable/google3",
+        "//packages/core/schematics/migrations/navigation-extras-omissions",
         "//packages/core/schematics/migrations/renderer-to-renderer2",
         "//packages/core/schematics/migrations/static-queries",
         "//packages/core/schematics/migrations/template-var-assignment",

packages/core/schematics/migrations/google3/navigationExtrasOmissionsRule.ts

@@ -0,0 +1,38 @@
+/**
+ * @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 {Replacement, RuleFailure, Rules} from 'tslint';
+import * as ts from 'typescript';
+import {findLiteralsToMigrate, migrateLiteral} from '../../migrations/navigation-extras-omissions/util';
+
+
+/** TSLint rule that migrates `navigateByUrl` and `createUrlTree` calls to an updated signature. */
+export class Rule extends Rules.TypedRule {
+  applyWithProgram(sourceFile: ts.SourceFile, program: ts.Program): RuleFailure[] {
+    const failures: RuleFailure[] = [];
+    const typeChecker = program.getTypeChecker();
+    const printer = ts.createPrinter();
+    const literalsToMigrate = findLiteralsToMigrate(sourceFile, typeChecker);
+
+    literalsToMigrate.forEach((instances, methodName) => instances.forEach(instance => {
+      const migratedNode = migrateLiteral(methodName, instance);
+
+      if (migratedNode !== instance) {
+        failures.push(new RuleFailure(
+            sourceFile, instance.getStart(), instance.getEnd(),
+            'Object used in navigateByUrl or createUrlTree call contains unsupported properties.',
+            this.ruleName,
+            new Replacement(
+                instance.getStart(), instance.getWidth(),
+                printer.printNode(ts.EmitHint.Unspecified, migratedNode, sourceFile))));
+      }
+    }));
+
+    return failures;
+  }
+}

packages/core/schematics/migrations/google3/rendererToRenderer2Rule.ts

@@ -8,10 +8,11 @@
 
 import {Replacement, RuleFailure, Rules} from 'tslint';
 import * as ts from 'typescript';
+import {getImportSpecifier} from '../../utils/typescript/imports';
 
 import {getHelper, HelperFunction} from '../renderer-to-renderer2/helpers';
 import {migrateExpression, replaceImport} from '../renderer-to-renderer2/migration';
-import {findCoreImport, findRendererReferences} from '../renderer-to-renderer2/util';
+import {findRendererReferences, getNamedImports} from '../renderer-to-renderer2/util';
 
 /**
  * TSLint rule that migrates from `Renderer` to `Renderer2`. More information on how it works:
@@ -22,18 +23,21 @@ export class Rule extends Rules.TypedRule {
     const typeChecker = program.getTypeChecker();
     const printer = ts.createPrinter();
     const failures: RuleFailure[] = [];
-    const rendererImport = findCoreImport(sourceFile, 'Renderer');
+    const rendererImportSpecifier = getImportSpecifier(sourceFile, '@angular/core', 'Renderer');
+    const rendererImport =
+        rendererImportSpecifier ? getNamedImports(rendererImportSpecifier) : null;
 
     // If there are no imports for the `Renderer`, we can exit early.
-    if (!rendererImport) {
+    if (!rendererImportSpecifier || !rendererImport) {
       return failures;
     }
 
     const {typedNodes, methodCalls, forwardRefs} =
-        findRendererReferences(sourceFile, typeChecker, rendererImport);
+        findRendererReferences(sourceFile, typeChecker, rendererImportSpecifier);
     const helpersToAdd = new Set<HelperFunction>();
 
-    failures.push(this._getNamedImportsFailure(rendererImport, sourceFile, printer));
+    failures.push(
+        this._getNamedImportsFailure(rendererImport, rendererImportSpecifier, sourceFile, printer));
     typedNodes.forEach(node => failures.push(this._getTypedNodeFailure(node, sourceFile)));
     forwardRefs.forEach(node => failures.push(this._getIdentifierNodeFailure(node, sourceFile)));
 
@@ -61,9 +65,10 @@ export class Rule extends Rules.TypedRule {
 
   /** Gets a failure for an import of the Renderer. */
   private _getNamedImportsFailure(
-      node: ts.NamedImports, sourceFile: ts.SourceFile, printer: ts.Printer): RuleFailure {
+      node: ts.NamedImports, importSpecifier: ts.ImportSpecifier, sourceFile: ts.SourceFile,
+      printer: ts.Printer): RuleFailure {
     const replacementText = printer.printNode(
-        ts.EmitHint.Unspecified, replaceImport(node, 'Renderer', 'Renderer2'), sourceFile);
+        ts.EmitHint.Unspecified, replaceImport(node, importSpecifier, 'Renderer2'), sourceFile);
 
     return new RuleFailure(
         sourceFile, node.getStart(), node.getEnd(),

packages/core/schematics/migrations/navigation-extras-omissions/BUILD.bazel

@@ -0,0 +1,18 @@
+load("//tools:defaults.bzl", "ts_library")
+
+ts_library(
+    name = "navigation-extras-omissions",
+    srcs = glob(["**/*.ts"]),
+    tsconfig = "//packages/core/schematics:tsconfig.json",
+    visibility = [
+        "//packages/core/schematics:__pkg__",
+        "//packages/core/schematics/migrations/google3:__pkg__",
+        "//packages/core/schematics/test:__pkg__",
+    ],
+    deps = [
+        "//packages/core/schematics/utils",
+        "@npm//@angular-devkit/schematics",
+        "@npm//@types/node",
+        "@npm//typescript",
+    ],
+)

packages/core/schematics/migrations/navigation-extras-omissions/README.md

@@ -0,0 +1,35 @@
+## Router.navigateByUrl and Router.createUrlTree extras migration
+
+Previously the `extras` parameter of `Router.navigateByUrl` and `Router.createUrlTree` accepted the
+full `NavigationExtras` object, even though only a subset of properties was supported. This
+migration removes the unsupported properties from the relevant method call sites.
+
+#### Before
+```ts
+import { Component } from '@angular/core';
+import { Router } from '@angular/router';
+
+@Component({})
+export class MyComponent {
+  constructor(private _router: Router) {}
+
+  goHome() {
+    this._router.navigateByUrl('/', {skipLocationChange: false, fragment: 'foo'});
+  }
+}
+```
+
+#### After
+```ts
+import { Component } from '@angular/core';
+import { Router } from '@angular/router';
+
+@Component({})
+export class MyComponent {
+  constructor(private _router: Router) {}
+
+  goHome() {
+    this._router.navigateByUrl('/', { /* Removed unsupported properties by Angular migration: fragment. */ skipLocationChange: false });
+  }
+}
+```

packages/core/schematics/migrations/navigation-extras-omissions/index.ts

@@ -0,0 +1,61 @@
+/**
+ * @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 {Rule, SchematicsException, Tree} from '@angular-devkit/schematics';
+import {relative} from 'path';
+import * as ts from 'typescript';
+
+import {getProjectTsConfigPaths} from '../../utils/project_tsconfig_paths';
+import {createMigrationProgram} from '../../utils/typescript/compiler_host';
+import {findLiteralsToMigrate, migrateLiteral} from './util';
+
+
+/** Migration that switches `Router.navigateByUrl` and `Router.createUrlTree` to a new signature. */
+export default function(): Rule {
+  return (tree: Tree) => {
+    const {buildPaths, testPaths} = getProjectTsConfigPaths(tree);
+    const basePath = process.cwd();
+    const allPaths = [...buildPaths, ...testPaths];
+
+    if (!allPaths.length) {
+      throw new SchematicsException(
+          'Could not find any tsconfig file. Cannot migrate ' +
+          'Router.navigateByUrl and Router.createUrlTree calls.');
+    }
+
+    for (const tsconfigPath of allPaths) {
+      runNavigationExtrasOmissionsMigration(tree, tsconfigPath, basePath);
+    }
+  };
+}
+
+function runNavigationExtrasOmissionsMigration(tree: Tree, tsconfigPath: string, basePath: string) {
+  const {program} = createMigrationProgram(tree, tsconfigPath, basePath);
+  const typeChecker = program.getTypeChecker();
+  const printer = ts.createPrinter();
+  const sourceFiles = program.getSourceFiles().filter(
+      f => !f.isDeclarationFile && !program.isSourceFileFromExternalLibrary(f));
+
+  sourceFiles.forEach(sourceFile => {
+    const literalsToMigrate = findLiteralsToMigrate(sourceFile, typeChecker);
+    const update = tree.beginUpdate(relative(basePath, sourceFile.fileName));
+
+    literalsToMigrate.forEach((instances, methodName) => instances.forEach(instance => {
+      const migratedNode = migrateLiteral(methodName, instance);
+
+      if (migratedNode !== instance) {
+        update.remove(instance.getStart(), instance.getWidth());
+        update.insertRight(
+            instance.getStart(),
+            printer.printNode(ts.EmitHint.Unspecified, migratedNode, sourceFile));
+      }
+    }));
+
+    tree.commitUpdate(update);
+  });
+}

packages/core/schematics/migrations/navigation-extras-omissions/util.ts

@@ -0,0 +1,125 @@
+/**
+ * @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';
+
+import {getImportSpecifier} from '../../utils/typescript/imports';
+import {isReferenceToImport} from '../../utils/typescript/symbol';
+
+/**
+ * Configures the methods that the migration should be looking for
+ * and the properties from `NavigationExtras` that should be preserved.
+ */
+const methodConfig = new Map<string, Set<string>>([
+  ['navigateByUrl', new Set<string>(['skipLocationChange', 'replaceUrl', 'state'])],
+  [
+    'createUrlTree', new Set<string>([
+      'relativeTo', 'queryParams', 'fragment', 'preserveQueryParams', 'queryParamsHandling',
+      'preserveFragment'
+    ])
+  ]
+]);
+
+export function migrateLiteral(
+    methodName: string, node: ts.ObjectLiteralExpression): ts.ObjectLiteralExpression {
+  const allowedProperties = methodConfig.get(methodName);
+
+  if (!allowedProperties) {
+    throw Error(`Attempting to migrate unconfigured method called ${methodName}.`);
+  }
+
+  const propertiesToKeep: ts.ObjectLiteralElementLike[] = [];
+  const removedPropertyNames: string[] = [];
+
+  node.properties.forEach(property => {
+    // Only look for regular and shorthand property assignments since resolving things
+    // like spread operators becomes too complicated for this migration.
+    if ((ts.isPropertyAssignment(property) || ts.isShorthandPropertyAssignment(property)) &&
+        (ts.isStringLiteralLike(property.name) || ts.isNumericLiteral(property.name) ||
+         ts.isIdentifier(property.name))) {
+      if (allowedProperties.has(property.name.text)) {
+        propertiesToKeep.push(property);
+      } else {
+        removedPropertyNames.push(property.name.text);
+      }
+    } else {
+      propertiesToKeep.push(property);
+    }
+  });
+
+  // Don't modify the node if there's nothing to remove.
+  if (removedPropertyNames.length === 0) {
+    return node;
+  }
+
+  // Note that the trailing/leading spaces are necessary so the comment looks good.
+  const removalComment =
+      ` Removed unsupported properties by Angular migration: ${removedPropertyNames.join(', ')}. `;
+
+  if (propertiesToKeep.length > 0) {
+    propertiesToKeep[0] = addUniqueLeadingComment(propertiesToKeep[0], removalComment);
+    return ts.createObjectLiteral(propertiesToKeep);
+  } else {
+    return addUniqueLeadingComment(ts.createObjectLiteral(propertiesToKeep), removalComment);
+  }
+}
+
+export function findLiteralsToMigrate(sourceFile: ts.SourceFile, typeChecker: ts.TypeChecker) {
+  const results = new Map<string, Set<ts.ObjectLiteralExpression>>(
+      Array.from(methodConfig.keys(), key => [key, new Set()]));
+  const routerImport = getImportSpecifier(sourceFile, '@angular/router', 'Router');
+  const seenLiterals = new Map<ts.ObjectLiteralExpression, string>();
+
+  if (routerImport) {
+    sourceFile.forEachChild(function visitNode(node: ts.Node) {
+      // Look for calls that look like `foo.<method to migrate>` with more than one parameter.
+      if (ts.isCallExpression(node) && node.arguments.length > 1 &&
+          ts.isPropertyAccessExpression(node.expression) && ts.isIdentifier(node.expression.name) &&
+          methodConfig.has(node.expression.name.text)) {
+        // Check whether the type of the object on which the
+        // function is called refers to the Router import.
+        if (isReferenceToImport(typeChecker, node.expression.expression, routerImport)) {
+          const methodName = node.expression.name.text;
+          const parameterDeclaration =
+              typeChecker.getTypeAtLocation(node.arguments[1]).getSymbol()?.valueDeclaration;
+
+          // Find the source of the object literal.
+          if (parameterDeclaration && ts.isObjectLiteralExpression(parameterDeclaration)) {
+            if (!seenLiterals.has(parameterDeclaration)) {
+              results.get(methodName)!.add(parameterDeclaration);
+              seenLiterals.set(parameterDeclaration, methodName);
+              // If the same literal has been passed into multiple different methods, we can't
+              // migrate it, because the supported properties are different. When we detect such
+              // a case, we drop it from the results so that it gets ignored. If it's used multiple
+              // times for the same method, it can still be migrated.
+            } else if (seenLiterals.get(parameterDeclaration) !== methodName) {
+              results.forEach(literals => literals.delete(parameterDeclaration));
+            }
+          }
+        }
+      } else {
+        node.forEachChild(visitNode);
+      }
+    });
+  }
+
+  return results;
+}
+
+/** Adds a leading comment to a node, if the node doesn't have such a comment already. */
+function addUniqueLeadingComment<T extends ts.Node>(node: T, comment: string): T {
+  const existingComments = ts.getSyntheticLeadingComments(node);
+
+  // This logic is primarily to ensure that we don't add the same comment multiple
+  // times when tslint runs over the same file again with outdated information.
+  if (!existingComments || existingComments.every(c => c.text !== comment)) {
+    return ts.addSyntheticLeadingComment(node, ts.SyntaxKind.MultiLineCommentTrivia, comment);
+  }
+
+  return node;
+}

packages/core/schematics/migrations/renderer-to-renderer2/index.ts

@@ -12,10 +12,11 @@ import * as ts from 'typescript';
 
 import {getProjectTsConfigPaths} from '../../utils/project_tsconfig_paths';
 import {createMigrationProgram} from '../../utils/typescript/compiler_host';
+import {getImportSpecifier} from '../../utils/typescript/imports';
 
 import {getHelper, HelperFunction} from './helpers';
 import {migrateExpression, replaceImport} from './migration';
-import {findCoreImport, findRendererReferences} from './util';
+import {findRendererReferences, getNamedImports} from './util';
 
 const MODULE_AUGMENTATION_FILENAME = 'ɵɵRENDERER_MIGRATION_CORE_AUGMENTATION.d.ts';
 
@@ -61,15 +62,17 @@ function runRendererToRenderer2Migration(tree: Tree, tsconfigPath: string, baseP
       f => !f.isDeclarationFile && !program.isSourceFileFromExternalLibrary(f));
 
   sourceFiles.forEach(sourceFile => {
-    const rendererImport = findCoreImport(sourceFile, 'Renderer');
+    const rendererImportSpecifier = getImportSpecifier(sourceFile, '@angular/core', 'Renderer');
+    const rendererImport =
+        rendererImportSpecifier ? getNamedImports(rendererImportSpecifier) : null;
 
     // If there are no imports for the `Renderer`, we can exit early.
-    if (!rendererImport) {
+    if (!rendererImportSpecifier || !rendererImport) {
       return;
     }
 
     const {typedNodes, methodCalls, forwardRefs} =
-        findRendererReferences(sourceFile, typeChecker, rendererImport);
+        findRendererReferences(sourceFile, typeChecker, rendererImportSpecifier);
     const update = tree.beginUpdate(relative(basePath, sourceFile.fileName));
     const helpersToAdd = new Set<HelperFunction>();
 
@@ -78,8 +81,8 @@ function runRendererToRenderer2Migration(tree: Tree, tsconfigPath: string, baseP
     update.insertRight(
         rendererImport.getStart(),
         printer.printNode(
-            ts.EmitHint.Unspecified, replaceImport(rendererImport, 'Renderer', 'Renderer2'),
+            ts.EmitHint.Unspecified,
-            sourceFile));
+            replaceImport(rendererImport, rendererImportSpecifier, 'Renderer2'), sourceFile));
 
     // Change the method parameter and property types to `Renderer2`.
     typedNodes.forEach(node => {

packages/core/schematics/migrations/renderer-to-renderer2/migration.ts

@@ -9,31 +9,28 @@
 import * as ts from 'typescript';
 
 import {HelperFunction} from './helpers';
-import {findImportSpecifier} from './util';
 
 /** A call expression that is based on a property access. */
 type PropertyAccessCallExpression = ts.CallExpression&{expression: ts.PropertyAccessExpression};
 
 /** Replaces an import inside an import statement with a different one. */
-export function replaceImport(node: ts.NamedImports, oldImport: string, newImport: string) {
+export function replaceImport(
-  const isAlreadyImported = findImportSpecifier(node.elements, newImport);
+    node: ts.NamedImports, existingImport: ts.ImportSpecifier, newImportName: string) {
+  const isAlreadyImported = node.elements.find(element => {
+    const {name, propertyName} = element;
+    return propertyName ? propertyName.text === newImportName : name.text === newImportName;
+  });
 
   if (isAlreadyImported) {
     return node;
   }
 
-  const existingImport = findImportSpecifier(node.elements, oldImport);
-
-  if (!existingImport) {
-    throw new Error(`Could not find an import to replace using ${oldImport}.`);
-  }
-
   return ts.updateNamedImports(node, [
     ...node.elements.filter(current => current !== existingImport),
     // Create a new import while trying to preserve the alias of the old one.
     ts.createImportSpecifier(
-        existingImport.propertyName ? ts.createIdentifier(newImport) : undefined,
+        existingImport.propertyName ? ts.createIdentifier(newImportName) : undefined,
-        existingImport.propertyName ? existingImport.name : ts.createIdentifier(newImport))
+        existingImport.propertyName ? existingImport.name : ts.createIdentifier(newImportName))
   ]);
 }
 

packages/core/schematics/migrations/renderer-to-renderer2/util.ts

@@ -8,30 +8,32 @@
 
 import * as ts from 'typescript';
 
+import {getImportSpecifier} from '../../utils/typescript/imports';
+import {isReferenceToImport} from '../../utils/typescript/symbol';
+
 /**
  * Finds typed nodes (e.g. function parameters or class properties) that are referencing the old
  * `Renderer`, as well as calls to the `Renderer` methods.
  */
 export function findRendererReferences(
-    sourceFile: ts.SourceFile, typeChecker: ts.TypeChecker, rendererImport: ts.NamedImports) {
+    sourceFile: ts.SourceFile, typeChecker: ts.TypeChecker,
+    rendererImportSpecifier: ts.ImportSpecifier) {
   const typedNodes = new Set<ts.ParameterDeclaration|ts.PropertyDeclaration|ts.AsExpression>();
   const methodCalls = new Set<ts.CallExpression>();
   const forwardRefs = new Set<ts.Identifier>();
-  const importSpecifier = findImportSpecifier(rendererImport.elements, 'Renderer');
+  const forwardRefSpecifier = getImportSpecifier(sourceFile, '@angular/core', 'forwardRef');
-  const forwardRefImport = findCoreImport(sourceFile, 'forwardRef');
-  const forwardRefSpecifier =
-      forwardRefImport ? findImportSpecifier(forwardRefImport.elements, 'forwardRef') : null;
 
   ts.forEachChild(sourceFile, function visitNode(node: ts.Node) {
     if ((ts.isParameter(node) || ts.isPropertyDeclaration(node)) &&
-        isReferenceToImport(typeChecker, node.name, importSpecifier)) {
+        isReferenceToImport(typeChecker, node.name, rendererImportSpecifier)) {
       typedNodes.add(node);
     } else if (
-        ts.isAsExpression(node) && isReferenceToImport(typeChecker, node.type, importSpecifier)) {
+        ts.isAsExpression(node) &&
+        isReferenceToImport(typeChecker, node.type, rendererImportSpecifier)) {
       typedNodes.add(node);
     } else if (ts.isCallExpression(node)) {
       if (ts.isPropertyAccessExpression(node.expression) &&
-          isReferenceToImport(typeChecker, node.expression.expression, importSpecifier)) {
+          isReferenceToImport(typeChecker, node.expression.expression, rendererImportSpecifier)) {
         methodCalls.add(node);
       } else if (
           // If we're dealing with a forwardRef that's returning a Renderer.
@@ -39,7 +41,7 @@ export function findRendererReferences(
           isReferenceToImport(typeChecker, node.expression, forwardRefSpecifier) &&
           node.arguments.length) {
         const rendererIdentifier =
-            findRendererIdentifierInForwardRef(typeChecker, node, importSpecifier);
+            findRendererIdentifierInForwardRef(typeChecker, node, rendererImportSpecifier);
         if (rendererIdentifier) {
           forwardRefs.add(rendererIdentifier);
         }
@@ -52,59 +54,27 @@ export function findRendererReferences(
   return {typedNodes, methodCalls, forwardRefs};
 }
 
-/** Finds the import from @angular/core that has a symbol with a particular name. */
+/** Gets the closest `NamedImports` to an `ImportSpecifier`. */
-export function findCoreImport(sourceFile: ts.SourceFile, symbolName: string): ts.NamedImports|
+export function getNamedImports(specifier: ts.ImportSpecifier): ts.NamedImports|null {
-    null {
+  let current: ts.Node = specifier;
-  // Only look through the top-level imports.
-  for (const node of sourceFile.statements) {
-    if (!ts.isImportDeclaration(node) || !ts.isStringLiteral(node.moduleSpecifier) ||
-        node.moduleSpecifier.text !== '@angular/core') {
-      continue;
-    }
 
-    const namedBindings = node.importClause && node.importClause.namedBindings;
+  while (current && !ts.isSourceFile(current)) {
-
+    if (ts.isNamedImports(current)) {
-    if (!namedBindings || !ts.isNamedImports(namedBindings)) {
+      return current;
-      continue;
-    }
-
-    if (findImportSpecifier(namedBindings.elements, symbolName)) {
-      return namedBindings;
     }
+    current = current.parent;
   }
 
   return null;
 }
 
-/** Finds an import specifier with a particular name, accounting for aliases. */
-export function findImportSpecifier(
-    elements: ts.NodeArray<ts.ImportSpecifier>, importName: string) {
-  return elements.find(element => {
-    const {name, propertyName} = element;
-    return propertyName ? propertyName.text === importName : name.text === importName;
-  }) ||
-      null;
-}
-
-/** Checks whether a node is referring to an import spcifier. */
-function isReferenceToImport(
-    typeChecker: ts.TypeChecker, node: ts.Node, importSpecifier: ts.ImportSpecifier|null): boolean {
-  if (importSpecifier) {
-    const nodeSymbol = typeChecker.getTypeAtLocation(node).getSymbol();
-    const importSymbol = typeChecker.getTypeAtLocation(importSpecifier).getSymbol();
-    return !!(nodeSymbol && importSymbol) &&
-        nodeSymbol.valueDeclaration === importSymbol.valueDeclaration;
-  }
-  return false;
-}
-
 /** Finds the identifier referring to the `Renderer` inside a `forwardRef` call expression. */
 function findRendererIdentifierInForwardRef(
     typeChecker: ts.TypeChecker, node: ts.CallExpression,
     rendererImport: ts.ImportSpecifier|null): ts.Identifier|null {
   const firstArg = node.arguments[0];
 
-  if (ts.isArrowFunction(firstArg)) {
+  if (ts.isArrowFunction(firstArg) && rendererImport) {
     // Check if the function is `forwardRef(() => Renderer)`.
     if (ts.isIdentifier(firstArg.body) &&
         isReferenceToImport(typeChecker, firstArg.body, rendererImport)) {

packages/core/schematics/test/BUILD.bazel

@@ -12,6 +12,7 @@ ts_library(
         "//packages/core/schematics/migrations/missing-injectable",
         "//packages/core/schematics/migrations/module-with-providers",
         "//packages/core/schematics/migrations/move-document",
+        "//packages/core/schematics/migrations/navigation-extras-omissions",
         "//packages/core/schematics/migrations/renderer-to-renderer2",
         "//packages/core/schematics/migrations/static-queries",
         "//packages/core/schematics/migrations/template-var-assignment",

packages/core/schematics/test/google3/navigation_extras_omissions_spec.ts

@@ -0,0 +1,334 @@
+/**
+ * @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 {readFileSync, writeFileSync} from 'fs';
+import {dirname, join} from 'path';
+import * as shx from 'shelljs';
+import {Configuration, Linter} from 'tslint';
+
+describe('Google3 NavigationExtras omissions TSLint rule', () => {
+  const rulesDirectory =
+      dirname(require.resolve('../../migrations/google3/navigationExtrasOmissionsRule'));
+
+  let tmpDir: string;
+
+  beforeEach(() => {
+    tmpDir = join(process.env['TEST_TMPDIR']!, 'google3-test');
+    shx.mkdir('-p', tmpDir);
+
+    // We need to declare the Angular symbols we're testing for, otherwise type checking won't work.
+    writeFile('router.d.ts', `
+      export declare class Router {
+        navigateByUrl(url: string, extras?: any);
+        createUrlTree(commands: any[], extras?: any);
+      }
+    `);
+
+    writeFile('tsconfig.json', JSON.stringify({
+      compilerOptions: {
+        module: 'es2015',
+        baseUrl: './',
+        paths: {
+          '@angular/router': ['router.d.ts'],
+        }
+      },
+    }));
+  });
+
+  afterEach(() => shx.rm('-r', tmpDir));
+
+  function runTSLint(fix: boolean) {
+    const program = Linter.createProgram(join(tmpDir, 'tsconfig.json'));
+    const linter = new Linter({fix, rulesDirectory: [rulesDirectory]}, program);
+    const config = Configuration.parseConfigFile({rules: {'navigation-extras-omissions': true}});
+
+    program.getRootFileNames().forEach(fileName => {
+      linter.lint(fileName, program.getSourceFile(fileName)!.getFullText(), config);
+    });
+
+    return linter;
+  }
+
+  function writeFile(fileName: string, content: string) {
+    writeFileSync(join(tmpDir, fileName), content);
+  }
+
+  function getFile(fileName: string) {
+    return readFileSync(join(tmpDir, fileName), 'utf8');
+  }
+
+  it('should flag objects with invalid properties used inside the relevant method calls', () => {
+    writeFile('/index.ts', `
+      import {Router} from '@angular/router';
+
+      class Navigator {
+        constructor(private _router: Router) {}
+
+        goHome() {
+          this._router.navigateByUrl('/', {fragment: 'foo'});
+        }
+
+        createTree() {
+          return this._router.createUrlTree(['/'], {state: {}});
+        }
+
+        goAway() {
+          this._router.navigateByUrl('/away');
+        }
+      }
+    `);
+
+    const linter = runTSLint(false);
+    const failures = linter.getResult().failures.map(failure => failure.getFailure());
+
+    expect(failures.length).toBe(2);
+    expect(failures[0])
+        .toMatch(
+            /Object used in navigateByUrl or createUrlTree call contains unsupported properties/);
+    expect(failures[1])
+        .toMatch(
+            /Object used in navigateByUrl or createUrlTree call contains unsupported properties/);
+  });
+
+  it('should not change calls with a single argument', () => {
+    writeFile('/index.ts', `
+      import {Router} from '@angular/router';
+
+      class Navigator {
+        constructor(private _router: Router) {}
+
+        goHome() {
+          this._router.navigateByUrl('/');
+        }
+      }
+
+      function createTree(router: Router) {
+        return router.createUrlTree(['/']);
+      }
+    `);
+
+    runTSLint(true);
+
+    const content = getFile('/index.ts');
+    expect(content).toContain(`this._router.navigateByUrl('/');`);
+    expect(content).toContain(`return router.createUrlTree(['/']);`);
+  });
+
+  it('should not change calls with an empty object literal', () => {
+    writeFile('/index.ts', `
+      import {Router} from '@angular/router';
+
+      class Navigator {
+        constructor(private _router: Router) {}
+
+        goHome() {
+          this._router.navigateByUrl('/', {});
+        }
+      }
+
+      function createTree(router: Router) {
+        return router.createUrlTree(['/'], {});
+      }
+    `);
+
+    runTSLint(true);
+
+    const content = getFile('/index.ts');
+    expect(content).toContain(`this._router.navigateByUrl('/', {});`);
+    expect(content).toContain(`return router.createUrlTree(['/'], {});`);
+  });
+
+  it('should not change objects that are used in multiple different methods', () => {
+    writeFile('/index.ts', `
+      import {Router} from '@angular/router';
+
+      const config = {replaceUrl: true, fragment: 'foo', state: {}};
+
+      class Navigator {
+        constructor(private _router: Router) {}
+
+        goHome() {
+          this._router.navigateByUrl('/', config);
+          return this._router.createUrlTree(['/'], config);
+        }
+      }
+    `);
+
+    runTSLint(true);
+
+    const content = getFile('/index.ts');
+    expect(content).toContain(`const config = {replaceUrl: true, fragment: 'foo', state: {}};`);
+  });
+
+  it('should preserve calls if the router does not come from @angular/router', () => {
+    writeFile('/index.ts', `
+      import {Router} from '@custom/router';
+
+      function createTree(router: Router) {
+        return router.createUrlTree(['/'], {foo: 1, bar: 2});
+      }
+    `);
+
+    runTSLint(true);
+
+    const content = getFile('/index.ts');
+    expect(content).toContain(`return router.createUrlTree(['/'], {foo: 1, bar: 2});`);
+  });
+
+  it('should change invalid navigateByUrl calls', () => {
+    writeFile('/index.ts', `
+      import {Router} from '@angular/router';
+
+      class Navigator {
+        constructor(private _router: Router) {}
+
+        goHome() {
+          this._router.navigateByUrl('/', {preserveFragment: false, skipLocationChange: false, fragment: 'foo'});
+        }
+      }
+    `);
+
+    runTSLint(true);
+
+    const content = getFile('/index.ts');
+    expect(content).toContain(
+        `this._router.navigateByUrl('/', { /* Removed unsupported properties by Angular migration: preserveFragment, fragment. */ skipLocationChange: false });`);
+  });
+
+  it('should change invalid navigateByUrl calls', () => {
+    writeFile('/index.ts', `
+      import {Router} from '@angular/router';
+
+      function createTree(router: Router) {
+        return router.createUrlTree(['/'], {replaceUrl: true, preserveFragment: true, state: {}});
+      }
+    `);
+
+    runTSLint(true);
+
+    const content = getFile('/index.ts');
+    expect(content).toContain(
+        `return router.createUrlTree(['/'], { /* Removed unsupported properties by Angular migration: replaceUrl, state. */ preserveFragment: true });`);
+  });
+
+  it('should set the comment outside the object if all properties were removed', () => {
+    writeFile('/index.ts', `
+      import {Router} from '@angular/router';
+
+      function navigate(router: Router) {
+        router.navigateByUrl('/', {fragment: 'foo'});
+      }
+    `);
+
+    runTSLint(true);
+
+    const content = getFile('/index.ts');
+    expect(content).toContain(
+        `router.navigateByUrl('/', /* Removed unsupported properties by Angular migration: fragment. */ {});`);
+  });
+
+  it('should migrate object literals defined as variables', () => {
+    writeFile('/index.ts', `
+      import {Router} from '@angular/router';
+
+      const config = {skipLocationChange: false, fragment: 'foo'};
+      const proxy = config;
+
+      function navigate(router: Router) {
+        router.navigateByUrl('/', proxy);
+      }
+    `);
+
+    runTSLint(true);
+
+    const content = getFile('/index.ts');
+    expect(content).toContain(
+        `const config = { /* Removed unsupported properties by Angular migration: fragment. */ skipLocationChange: false };`);
+    expect(content).toContain(`const proxy = config;`);
+    expect(content).toContain(`router.navigateByUrl('/', proxy);`);
+  });
+
+  it('should pick up calls where the router is returned by a function', () => {
+    writeFile('/index.ts', `
+      import {Router} from '@angular/router';
+
+      function navigate(router: Router) {
+        getRouter().navigateByUrl('/', {fragment: 'foo'});
+      }
+
+      function getRouter() {
+        return {} as Router;
+      }
+    `);
+
+    runTSLint(true);
+
+    const content = getFile('/index.ts');
+    expect(content).toContain(
+        `getRouter().navigateByUrl('/', /* Removed unsupported properties by Angular migration: fragment. */ {});`);
+  });
+
+  it('should pick up calls where the router is aliased', () => {
+    writeFile('/index.ts', `
+      import {Router as AliasedRouter} from '@angular/router';
+
+      function navigate(router: AliasedRouter) {
+        router.navigateByUrl('/', {fragment: 'foo'});
+      }
+    `);
+
+    runTSLint(true);
+
+    const content = getFile('/index.ts');
+    expect(content).toContain(
+        `router.navigateByUrl('/', /* Removed unsupported properties by Angular migration: fragment. */ {});`);
+  });
+
+  it('should preserve object spread assignments', () => {
+    writeFile('/index.ts', `
+      import {Router} from '@angular/router';
+
+      function navigate(router: Router) {
+        const overrides = {foo: 1};
+        router.navigateByUrl('/', {replaceUrl: true, fragment: 'foo', ...overrides});
+      }
+    `);
+
+    runTSLint(true);
+
+    const content = getFile('/index.ts');
+    expect(content).toContain(
+        `router.navigateByUrl('/', { /* Removed unsupported properties by Angular migration: fragment. */ replaceUrl: true, ...overrides });`);
+  });
+
+  it('should migrate objects that are used in multiple calls of the same method', () => {
+    writeFile('/index.ts', `
+      import {Router} from '@angular/router';
+
+      const config = {skipLocationChange: false, fragment: 'foo'};
+
+      class Navigator {
+        constructor(private _router: Router) {}
+
+        goHome() {
+          this._router.navigateByUrl('/', config);
+        }
+
+        goFish() {
+          this._router.navigateByUrl('/fish', config);
+        }
+      }
+    `);
+
+    runTSLint(true);
+
+    const content = getFile('/index.ts');
+    expect(content).toContain(
+        `const config = { /* Removed unsupported properties by Angular migration: fragment. */ skipLocationChange: false };`);
+  });
+});

packages/core/schematics/test/google3/renderer_to_renderer2_spec.ts

@@ -105,6 +105,26 @@ describe('Google3 Renderer to Renderer2 TSLint rule', () => {
     expect(content).toContain('(renderer: Renderer2)');
   });
 
+  it('should not change Renderer imports if Renderer2 is already imported', () => {
+    writeFile('/index.ts', `
+        import { Renderer, Component, Renderer2 } from '@angular/core';
+
+        @Component({template: ''})
+        export class MyComp {
+          public renderer: Renderer;
+
+          constructor(renderer: Renderer) {
+            this.renderer = renderer;
+          }
+        }
+      `);
+
+    runTSLint(true);
+    const content = getFile('index.ts');
+
+    expect(content).toContain(`import { Renderer, Component, Renderer2 } from '@angular/core';`);
+  });
+
   it('should change Renderer inside single-line forwardRefs to Renderer2', () => {
     writeFile('/index.ts', `
       import { Renderer, Component, forwardRef, Inject } from '@angular/core';

packages/core/schematics/test/navigation_extras_omissions_migration_spec.ts

@@ -0,0 +1,302 @@
+/**
+ * @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 {getSystemPath, normalize, virtualFs} from '@angular-devkit/core';
+import {TempScopedNodeJsSyncHost} from '@angular-devkit/core/node/testing';
+import {HostTree} from '@angular-devkit/schematics';
+import {SchematicTestRunner, UnitTestTree} from '@angular-devkit/schematics/testing';
+import * as shx from 'shelljs';
+
+describe('NavigationExtras omissions migration', () => {
+  let runner: SchematicTestRunner;
+  let host: TempScopedNodeJsSyncHost;
+  let tree: UnitTestTree;
+  let tmpDirPath: string;
+  let previousWorkingDir: string;
+
+  beforeEach(() => {
+    runner = new SchematicTestRunner('test', require.resolve('../migrations.json'));
+    host = new TempScopedNodeJsSyncHost();
+    tree = new UnitTestTree(new HostTree(host));
+
+    writeFile('/tsconfig.json', JSON.stringify({
+      compilerOptions: {
+        lib: ['es2015'],
+        strictNullChecks: true,
+      },
+    }));
+    writeFile('/angular.json', JSON.stringify({
+      projects: {t: {architect: {build: {options: {tsConfig: './tsconfig.json'}}}}}
+    }));
+    // We need to declare the Angular symbols we're testing for, otherwise type checking won't work.
+    writeFile('/node_modules/@angular/router/index.d.ts', `
+      export declare class Router {
+        navigateByUrl(url: string, extras?: any);
+        createUrlTree(commands: any[], extras?: any);
+      }
+    `);
+
+    previousWorkingDir = shx.pwd();
+    tmpDirPath = getSystemPath(host.root);
+
+    // Switch into the temporary directory path. This allows us to run
+    // the schematic against our custom unit test tree.
+    shx.cd(tmpDirPath);
+  });
+
+  afterEach(() => {
+    shx.cd(previousWorkingDir);
+    shx.rm('-r', tmpDirPath);
+  });
+
+  it('should not change calls with a single argument', async () => {
+    writeFile('/index.ts', `
+      import {Router} from '@angular/router';
+
+      class Navigator {
+        constructor(private _router: Router) {}
+
+        goHome() {
+          this._router.navigateByUrl('/');
+        }
+      }
+
+      function createTree(router: Router) {
+        return router.createUrlTree(['/']);
+      }
+    `);
+
+    await runMigration();
+
+    const content = tree.readContent('/index.ts');
+    expect(content).toContain(`this._router.navigateByUrl('/');`);
+    expect(content).toContain(`return router.createUrlTree(['/']);`);
+  });
+
+  it('should not change calls with an empty object literal', async () => {
+    writeFile('/index.ts', `
+      import {Router} from '@angular/router';
+
+      class Navigator {
+        constructor(private _router: Router) {}
+
+        goHome() {
+          this._router.navigateByUrl('/', {});
+        }
+      }
+
+      function createTree(router: Router) {
+        return router.createUrlTree(['/'], {});
+      }
+    `);
+
+    await runMigration();
+
+    const content = tree.readContent('/index.ts');
+    expect(content).toContain(`this._router.navigateByUrl('/', {});`);
+    expect(content).toContain(`return router.createUrlTree(['/'], {});`);
+  });
+
+  it('should not change objects that are used in multiple different methods', async () => {
+    writeFile('/index.ts', `
+      import {Router} from '@angular/router';
+
+      const config = {replaceUrl: true, fragment: 'foo', state: {}};
+
+      class Navigator {
+        constructor(private _router: Router) {}
+
+        goHome() {
+          this._router.navigateByUrl('/', config);
+          return this._router.createUrlTree(['/'], config);
+        }
+      }
+    `);
+
+    await runMigration();
+
+    const content = tree.readContent('/index.ts');
+    expect(content).toContain(`const config = {replaceUrl: true, fragment: 'foo', state: {}};`);
+  });
+
+  it('should preserve calls if the router does not come from @angular/router', async () => {
+    writeFile('/index.ts', `
+      import {Router} from '@custom/router';
+
+      function createTree(router: Router) {
+        return router.createUrlTree(['/'], {foo: 1, bar: 2});
+      }
+    `);
+
+    await runMigration();
+
+    const content = tree.readContent('/index.ts');
+    expect(content).toContain(`return router.createUrlTree(['/'], {foo: 1, bar: 2});`);
+  });
+
+  it('should change invalid navigateByUrl calls', async () => {
+    writeFile('/index.ts', `
+      import {Router} from '@angular/router';
+
+      class Navigator {
+        constructor(private _router: Router) {}
+
+        goHome() {
+          this._router.navigateByUrl('/', {preserveFragment: false, skipLocationChange: false, fragment: 'foo'});
+        }
+      }
+    `);
+
+    await runMigration();
+
+    const content = tree.readContent('/index.ts');
+    expect(content).toContain(
+        `this._router.navigateByUrl('/', { /* Removed unsupported properties by Angular migration: preserveFragment, fragment. */ skipLocationChange: false });`);
+  });
+
+  it('should change invalid navigateByUrl calls', async () => {
+    writeFile('/index.ts', `
+      import {Router} from '@angular/router';
+
+      function createTree(router: Router) {
+        return router.createUrlTree(['/'], {replaceUrl: true, preserveFragment: true, state: {}});
+      }
+    `);
+
+    await runMigration();
+
+    const content = tree.readContent('/index.ts');
+    expect(content).toContain(
+        `return router.createUrlTree(['/'], { /* Removed unsupported properties by Angular migration: replaceUrl, state. */ preserveFragment: true });`);
+  });
+
+  it('should set the comment outside the object if all properties were removed', async () => {
+    writeFile('/index.ts', `
+      import {Router} from '@angular/router';
+
+      function navigate(router: Router) {
+        router.navigateByUrl('/', {fragment: 'foo'});
+      }
+    `);
+
+    await runMigration();
+
+    const content = tree.readContent('/index.ts');
+    expect(content).toContain(
+        `router.navigateByUrl('/', /* Removed unsupported properties by Angular migration: fragment. */ {});`);
+  });
+
+  it('should migrate object literals defined as variables', async () => {
+    writeFile('/index.ts', `
+      import {Router} from '@angular/router';
+
+      const config = {skipLocationChange: false, fragment: 'foo'};
+      const proxy = config;
+
+      function navigate(router: Router) {
+        router.navigateByUrl('/', proxy);
+      }
+    `);
+
+    await runMigration();
+
+    const content = tree.readContent('/index.ts');
+    expect(content).toContain(
+        `const config = { /* Removed unsupported properties by Angular migration: fragment. */ skipLocationChange: false };`);
+    expect(content).toContain(`const proxy = config;`);
+    expect(content).toContain(`router.navigateByUrl('/', proxy);`);
+  });
+
+  it('should pick up calls where the router is returned by a function', async () => {
+    writeFile('/index.ts', `
+      import {Router} from '@angular/router';
+
+      function navigate(router: Router) {
+        getRouter().navigateByUrl('/', {fragment: 'foo'});
+      }
+
+      function getRouter() {
+        return {} as Router;
+      }
+    `);
+
+    await runMigration();
+
+    const content = tree.readContent('/index.ts');
+    expect(content).toContain(
+        `getRouter().navigateByUrl('/', /* Removed unsupported properties by Angular migration: fragment. */ {});`);
+  });
+
+  it('should pick up calls where the router is aliased', async () => {
+    writeFile('/index.ts', `
+      import {Router as AliasedRouter} from '@angular/router';
+
+      function navigate(router: AliasedRouter) {
+        router.navigateByUrl('/', {fragment: 'foo'});
+      }
+    `);
+
+    await runMigration();
+
+    const content = tree.readContent('/index.ts');
+    expect(content).toContain(
+        `router.navigateByUrl('/', /* Removed unsupported properties by Angular migration: fragment. */ {});`);
+  });
+
+  it('should preserve object spread assignments', async () => {
+    writeFile('/index.ts', `
+      import {Router} from '@angular/router';
+
+      function navigate(router: Router) {
+        const overrides = {foo: 1};
+        router.navigateByUrl('/', {replaceUrl: true, fragment: 'foo', ...overrides});
+      }
+    `);
+
+    await runMigration();
+
+    const content = tree.readContent('/index.ts');
+    expect(content).toContain(
+        `router.navigateByUrl('/', { /* Removed unsupported properties by Angular migration: fragment. */ replaceUrl: true, ...overrides });`);
+  });
+
+  it('should migrate objects that are used in multiple calls of the same method', async () => {
+    writeFile('/index.ts', `
+      import {Router} from '@angular/router';
+
+      const config = {skipLocationChange: false, fragment: 'foo'};
+
+      class Navigator {
+        constructor(private _router: Router) {}
+
+        goHome() {
+          this._router.navigateByUrl('/', config);
+        }
+
+        goFish() {
+          this._router.navigateByUrl('/fish', config);
+        }
+      }
+    `);
+
+    await runMigration();
+
+    const content = tree.readContent('/index.ts');
+    expect(content).toContain(
+        `const config = { /* Removed unsupported properties by Angular migration: fragment. */ skipLocationChange: false };`);
+  });
+
+  function writeFile(filePath: string, contents: string) {
+    host.sync.write(normalize(filePath), virtualFs.stringToFileBuffer(contents));
+  }
+
+  function runMigration() {
+    return runner.runSchematicAsync('migration-v11-navigation-extras-omissions', {}, tree)
+        .toPromise();
+  }
+});

packages/core/schematics/test/renderer_to_renderer2_migration_spec.ts

@@ -99,6 +99,21 @@ describe('Renderer to Renderer2 migration', () => {
       expect(content).toContain(`import { Component } from '@angular/core';`);
       expect(content).toContain(`import { Renderer } from './my-renderer';`);
     });
+
+    it('should not change imports if Renderer2 was already imported', async () => {
+      writeFile('/index.ts', `
+          import { Renderer, Component, Renderer2 } from '@angular/core';
+
+          @Component({template: ''})
+          export class MyComp {
+            constructor(renderer: Renderer) {}
+          }
+        `);
+
+      await runMigration();
+      expect(tree.readContent('/index.ts'))
+          .toContain(`import { Renderer, Component, Renderer2 } from '@angular/core';`);
+    });
   });
 
   describe('type renaming', () => {

packages/core/schematics/utils/typescript/imports.ts

@@ -42,3 +42,43 @@ export function getImportOfIdentifier(typeChecker: ts.TypeChecker, node: ts.Iden
     node: importDecl
   };
 }
+
+
+/**
+ * Gets a top-level import specifier with a specific name that is imported from a particular module.
+ * E.g. given a file that looks like:
+ *
+ * ```
+ * import { Component, Directive } from '@angular/core';
+ * import { Foo } from './foo';
+ * ```
+ *
+ * Calling `getImportSpecifier(sourceFile, '@angular/core', 'Directive')` will yield the node
+ * referring to `Directive` in the top import.
+ *
+ * @param sourceFile File in which to look for imports.
+ * @param moduleName Name of the import's module.
+ * @param specifierName Original name of the specifier to look for. Aliases will be resolved to
+ *    their original name.
+ */
+export function getImportSpecifier(
+    sourceFile: ts.SourceFile, moduleName: string, specifierName: string): ts.ImportSpecifier|null {
+  for (const node of sourceFile.statements) {
+    if (ts.isImportDeclaration(node) && ts.isStringLiteral(node.moduleSpecifier) &&
+        node.moduleSpecifier.text === moduleName) {
+      const namedBindings = node.importClause && node.importClause.namedBindings;
+      if (namedBindings && ts.isNamedImports(namedBindings)) {
+        const match = namedBindings.elements.find(element => {
+          const {name, propertyName} = element;
+          return propertyName ? propertyName.text === specifierName : name.text === specifierName;
+        });
+
+        if (match) {
+          return match;
+        }
+      }
+    }
+  }
+
+  return null;
+}

packages/core/schematics/utils/typescript/symbol.ts

@@ -18,3 +18,12 @@ export function getValueSymbolOfDeclaration(node: ts.Node, typeChecker: ts.TypeC
 
   return symbol;
 }
+
+/** Checks whether a node is referring to a specific import specifier. */
+export function isReferenceToImport(
+    typeChecker: ts.TypeChecker, node: ts.Node, importSpecifier: ts.ImportSpecifier): boolean {
+  const nodeSymbol = typeChecker.getTypeAtLocation(node).getSymbol();
+  const importSymbol = typeChecker.getTypeAtLocation(importSpecifier).getSymbol();
+  return !!(nodeSymbol && importSymbol) &&
+      nodeSymbol.valueDeclaration === importSymbol.valueDeclaration;
+}