refactor: reduce direct babel dependencies

The `@babel/core` package provides the functionality of multiple other babel packages
without the need to directly depend or import the other babel packages. Since the
`@babel/core` package is already used and imported in the locations that previously
used the other babel packages, an overall reduction in both imports and dependencies
is possible. Six babel related packages were able to be removed from the root `package.json`
and one (also present in the aforementioned six) was removed as a dependency from the
`@angular/localize` package.

The following packages were removed:

goldens/public-api/localize/tools/index.md

@@ -6,13 +6,12 @@
 
 /// <reference types="@angular/compiler-cli/private/babel" />
 /// <reference types="@types/babel__core" />
-/// <reference types="@types/babel__traverse" />
 
 import { AbsoluteFsPath } from '@angular/compiler-cli/private/localize';
 import { Element as Element_2 } from '@angular/compiler';
 import { Logger } from '@angular/compiler-cli/private/localize';
 import { MessageId } from '@angular/localize';
-import { NodePath } from '@babel/traverse';
+import { NodePath } from '@babel/core';
 import { ParseError } from '@angular/compiler';
 import { PathManipulation } from '@angular/compiler-cli/private/localize';
 import { PluginObj } from '@babel/core';

package.json

@@ -57,11 +57,7 @@
     "@babel/core": "7.23.2",
     "@babel/generator": "7.23.0",
     "@babel/helper-replace-supers": "7.22.20",
-    "@babel/parser": "7.23.0",
     "@babel/preset-env": "7.23.2",
-    "@babel/template": "7.22.15",
-    "@babel/traverse": "7.23.2",
-    "@babel/types": "7.23.0",
     "@bazel/concatjs": "5.8.1",
     "@bazel/esbuild": "5.8.1",
     "@bazel/jasmine": "5.8.1",
@@ -79,8 +75,6 @@
     "@types/angular": "^1.6.47",
     "@types/babel__core": "7.20.2",
     "@types/babel__generator": "7.6.5",
-    "@types/babel__template": "7.4.2",
-    "@types/babel__traverse": "7.20.2",
     "@types/bluebird": "^3.5.27",
     "@types/chrome": "^0.0.248",
     "@types/convert-source-map": "^2.0.0",

packages/compiler-cli/linker/babel/BUILD.bazel

@@ -16,6 +16,5 @@ ts_library(
         "//packages/compiler-cli/src/ngtsc/translator",
         "@npm//@babel/core",
         "@npm//@types/babel__core",
-        "@npm//@types/babel__traverse",
     ],
 )

packages/compiler-cli/linker/babel/src/babel_declaration_scope.ts

@@ -5,8 +5,7 @@
  * 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 {types as t} from '@babel/core';
-import {NodePath, Scope} from '@babel/traverse';
+import {NodePath, types as t} from '@babel/core';
 
 import {DeclarationScope} from '../../../linker';
 
@@ -25,7 +24,7 @@ export class BabelDeclarationScope implements DeclarationScope<ConstantScopePath
    *
    * @param declarationScope the Babel scope containing the declaration call expression.
    */
-  constructor(private declarationScope: Scope) {}
+  constructor(private declarationScope: NodePath['scope']) {}
 
   /**
    * Compute the Babel `NodePath` that can be used to reference the lexical scope where any

packages/compiler-cli/linker/babel/src/es2015_linker_plugin.ts

@@ -6,8 +6,7 @@
  * found in the LICENSE file at https://angular.io/license
  */
 
-import {BabelFile, PluginObj, types as t} from '@babel/core';
-import {NodePath} from '@babel/traverse';
+import {BabelFile, NodePath, PluginObj, types as t} from '@babel/core';
 
 import {FileLinker, isFatalLinkerError, LinkerEnvironment} from '../../../linker';
 
@@ -33,11 +32,11 @@ export function createEs2015LinkerPlugin({fileSystem, logger, ...options}: Linke
         /**
          * Create a new `FileLinker` as we enter each file (`t.Program` in Babel).
          */
-        enter(path: NodePath<t.Program>): void {
+        enter(_, state): void {
           assertNull(fileLinker);
           // Babel can be configured with a `filename` or `relativeFilename` (or both, or neither) -
           // possibly relative to the optional `cwd` path.
-          const file = path.hub.file;
+          const file = state.file;
           const filename = file.opts.filename ?? file.opts.filenameRelative;
           if (!filename) {
             throw new Error(
@@ -67,7 +66,7 @@ export function createEs2015LinkerPlugin({fileSystem, logger, ...options}: Linke
        * Test each call expression to see if it is a partial declaration; it if is then replace it
        * with the results of linking the declaration.
        */
-      CallExpression(call: NodePath<t.CallExpression>): void {
+      CallExpression(call: NodePath<t.CallExpression>, state): void {
         if (fileLinker === null) {
           // Any statements that are inserted upon program exit will be visited outside of an active
           // linker context. These call expressions are known not to contain partial declarations,
@@ -91,7 +90,7 @@ export function createEs2015LinkerPlugin({fileSystem, logger, ...options}: Linke
           call.replaceWith(replacement);
         } catch (e) {
           const node = isFatalLinkerError(e) ? e.node as t.Node : call.node;
-          throw buildCodeFrameError(call.hub.file, (e as Error).message, node);
+          throw buildCodeFrameError(state.file, (e as Error).message, node);
         }
       }
     }
@@ -176,6 +175,6 @@ function assertNotNull<T>(obj: T|null): asserts obj is T {
  */
 function buildCodeFrameError(file: BabelFile, message: string, node: t.Node): string {
   const filename = file.opts.filename || '(unknown file)';
-  const error = file.buildCodeFrameError(node, message);
+  const error = file.hub.buildError(node, message);
   return `${filename}: ${error.message}`;
 }

packages/compiler-cli/linker/babel/test/BUILD.bazel

@@ -18,13 +18,8 @@ ts_library(
         "//packages/compiler-cli/src/ngtsc/logging/testing",
         "//packages/compiler-cli/src/ngtsc/translator",
         "@npm//@babel/generator",
-        "@npm//@babel/parser",
-        "@npm//@babel/template",
-        "@npm//@babel/traverse",
         "@npm//@types/babel__core",
         "@npm//@types/babel__generator",
-        "@npm//@types/babel__template",
-        "@npm//@types/babel__traverse",
     ],
 )
 

packages/compiler-cli/linker/babel/test/ast/babel_ast_factory_spec.ts

@@ -6,9 +6,8 @@
  * found in the LICENSE file at https://angular.io/license
  */
 import {leadingComment} from '@angular/compiler';
-import {types as t} from '@babel/core';
+import {template, types as t} from '@babel/core';
 import _generate from '@babel/generator';
-import _template from '@babel/template';
 
 import {BabelAstFactory} from '../../src/ast/babel_ast_factory';
 
@@ -18,8 +17,8 @@ const generate = (_generate as any)['default'] as typeof _generate;
 
 // Exposes shorthands for the `expression` and `statement`
 // methods exposed by `@babel/template`.
-const expression = _template.expression;
-const statement = _template.statement;
+const expression = template.expression;
+const statement = template.statement;
 
 describe('BabelAstFactory', () => {
   let factory: BabelAstFactory;

packages/compiler-cli/linker/babel/test/ast/babel_ast_host_spec.ts

@@ -5,16 +5,10 @@
  * 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 {types as t} from '@babel/core';
-import parser from '@babel/parser';
-import _template from '@babel/template';
+import {parse, template, types as t} from '@babel/core';
 
 import {BabelAstHost} from '../../src/ast/babel_ast_host';
 
-// Babel is a CJS package and misuses the `default` named binding:
-// https://github.com/babel/babel/issues/15269.
-const template = (_template as any)['default'] as typeof _template;
-
 describe('BabelAstHost', () => {
   let host: BabelAstHost;
   beforeEach(() => host = new BabelAstHost());
@@ -331,8 +325,8 @@ describe('BabelAstHost', () => {
 
   describe('getRange()', () => {
     it('should extract the range from the expression', () => {
-      const file = parser.parse('// preamble\nx = \'moo\';');
-      const stmt = file.program.body[0] as t.Statement;
+      const file = parse('// preamble\nx = \'moo\';');
+      const stmt = file!.program.body[0] as t.Statement;
       assertExpressionStatement(stmt);
       assertAssignmentExpression(stmt.expression);
       expect(host.getRange(stmt.expression.right))

packages/compiler-cli/linker/babel/test/babel_declaration_scope_spec.ts

@@ -6,20 +6,14 @@
  * found in the LICENSE file at https://angular.io/license
  */
 
-import {types as t} from '@babel/core';
-import parser from '@babel/parser';
-import _traverse, {NodePath} from '@babel/traverse';
+import {NodePath, parse, traverse, types as t} from '@babel/core';
 
 import {BabelDeclarationScope} from '../src/babel_declaration_scope';
 
-// Babel is a CJS package and misuses the `default` named binding:
-// https://github.com/babel/babel/issues/15269.
-const traverse = (_traverse as any)['default'] as typeof _traverse;
-
 describe('BabelDeclarationScope', () => {
   describe('getConstantScopeRef()', () => {
     it('should return a path to the ES module where the expression was imported', () => {
-      const ast = parser.parse(
+      const ast = parse(
                       [
                         'import * as core from \'@angular/core\';',
                         'function foo() {',
@@ -35,7 +29,7 @@ describe('BabelDeclarationScope', () => {
     });
 
     it('should return a path to the ES Module where the expression is declared', () => {
-      const ast = parser.parse(
+      const ast = parse(
                       [
                         'var core;',
                         'export function foo() {',
@@ -51,7 +45,7 @@ describe('BabelDeclarationScope', () => {
     });
 
     it('should return null if the file is not an ES module', () => {
-      const ast = parser.parse(
+      const ast = parse(
                       [
                         'var core;',
                         'function foo() {',
@@ -66,7 +60,7 @@ describe('BabelDeclarationScope', () => {
     });
 
     it('should return the IIFE factory function where the expression is a parameter', () => {
-      const ast = parser.parse(
+      const ast = parse(
                       [
                         'var core;',
                         '(function(core) {',

packages/compiler-cli/private/babel.d.ts

@@ -5,23 +5,6 @@
  * 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 { BabelFile, types as t } from '@babel/core';
-
-/**
- * Augment some Babel types to add symbols that we rely on, but are not included in the Babel typings.
- */
-
-declare module '@babel/traverse' {
-  interface Hub {
-    file: BabelFile;
-  }
-}
-
-declare module '@babel/core' {
-  interface BabelFile {
-    buildCodeFrameError(node: t.Node, message: string): Error;
-  }
-}
 
 // The following modules are declared to work around a limitation in tsc_wrapped's `strict_deps`
 // check. Since Babel uses scoped packages, the corresponding lookup for declaration files in the
@@ -37,6 +20,5 @@ declare module '@babel/core' {
 // that is not governed by Bazel, and therefore not expected by the `strict_deps` rule.
 // Declaring the modules here allows `strict_deps` to always find a declaration of the modules
 // in an input file to the compilation, therefore accepting the module import.
+declare module '@babel/core' {}
 declare module '@babel/generator' {}
-declare module '@babel/template' {}
-declare module '@babel/parser' {}

packages/localize/package.json

@@ -36,7 +36,6 @@
   "dependencies": {
     "@babel/core": "7.23.2",
     "@types/babel__core": "7.20.2",
-    "@types/babel__traverse": "7.20.2",
     "fast-glob": "3.3.1",
     "yargs": "^17.2.1"
   },

packages/localize/tools/BUILD.bazel

@@ -15,7 +15,6 @@ ts_library(
         "//packages/localize",
         "@npm//@babel/core",
         "@npm//@types/babel__core",
-        "@npm//@types/babel__traverse",
         "@npm//@types/node",
         "@npm//@types/yargs",
         "@npm//fast-glob",

packages/localize/tools/src/extract/source_files/es5_extract_plugin.ts

@@ -15,7 +15,7 @@ export function makeEs5ExtractPlugin(
     fs: PathManipulation, messages: ɵParsedMessage[], localizeName = '$localize'): PluginObj {
   return {
     visitor: {
-      CallExpression(callPath: NodePath<t.CallExpression>) {
+      CallExpression(callPath: NodePath<t.CallExpression>, state) {
         try {
           const calleePath = callPath.get('callee');
           if (isNamedIdentifier(calleePath, localizeName) && isGlobalIdentifier(calleePath)) {
@@ -34,7 +34,7 @@ export function makeEs5ExtractPlugin(
             // If we get a BabelParseError here then something went wrong with Babel itself
             // since there must be something wrong with the structure of the AST generated
             // by Babel parsing a TaggedTemplateExpression.
-            throw buildCodeFrameError(fs, callPath, e);
+            throw buildCodeFrameError(fs, callPath, state.file, e);
           } else {
             throw e;
           }

packages/localize/tools/src/source_file_utils.ts

@@ -7,8 +7,7 @@
  */
 import {AbsoluteFsPath, getFileSystem, PathManipulation} from '@angular/compiler-cli/private/localize';
 import {ɵisMissingTranslationError, ɵmakeTemplateObject, ɵParsedTranslation, ɵSourceLocation, ɵtranslate} from '@angular/localize';
-import {types as t} from '@babel/core';
-import {NodePath} from '@babel/traverse';
+import {BabelFile, NodePath, types as t} from '@babel/core';
 
 import {DiagnosticHandlingStrategy, Diagnostics} from './diagnostics';
 
@@ -404,19 +403,19 @@ export function isBabelParseError(e: any): e is BabelParseError {
 }
 
 export function buildCodeFrameError(
-    fs: PathManipulation, path: NodePath, e: BabelParseError): string {
-  let filename = path.hub.file.opts.filename;
+    fs: PathManipulation, path: NodePath, file: BabelFile, e: BabelParseError): string {
+  let filename = file.opts.filename;
   if (filename) {
     filename = fs.resolve(filename);
-    let cwd = path.hub.file.opts.cwd;
+    let cwd = file.opts.cwd;
     if (cwd) {
       cwd = fs.resolve(cwd);
       filename = fs.relative(cwd, filename);
     }
   } else {
     filename = '(unknown file)';
   }
-  const message = path.hub.file.buildCodeFrameError(e.node, e.message).message;
+  const {message} = file.hub.buildError(e.node, e.message);
   return `${filename}: ${message}`;
 }
 
@@ -435,7 +434,7 @@ export function getLocation(
     start: getLineAndColumn(startLocation.start),
     end: getLineAndColumn(endLocation.end),
     file,
-    text: getText(startPath),
+    text: startPath.getSource() || undefined,
   };
 }
 
@@ -447,7 +446,8 @@ export function serializeLocationPosition(location: ɵSourceLocation): string {
 }
 
 function getFileFromPath(fs: PathManipulation, path: NodePath|undefined): AbsoluteFsPath|null {
-  const opts = path?.hub.file.opts;
+  // The file field is not guaranteed to be present for all node paths
+  const opts = (path?.hub as {file?: BabelFile}).file?.opts;
   const filename = opts?.filename;
   if (!filename || !opts.cwd) {
     return null;
@@ -462,10 +462,3 @@ function getLineAndColumn(loc: {line: number, column: number}): {line: number, c
   // Note we want 0-based line numbers but Babel returns 1-based.
   return {line: loc.line - 1, column: loc.column};
 }
-
-function getText(path: NodePath): string|undefined {
-  if (path.node.start == null || path.node.end == null) {
-    return undefined;
-  }
-  return path.hub.file.code.substring(path.node.start, path.node.end);
-}

packages/localize/tools/src/translate/source_files/es2015_translate_plugin.ts

@@ -24,7 +24,7 @@ export function makeEs2015TranslatePlugin(
     fs: PathManipulation = getFileSystem()): PluginObj {
   return {
     visitor: {
-      TaggedTemplateExpression(path: NodePath<t.TaggedTemplateExpression>) {
+      TaggedTemplateExpression(path: NodePath<t.TaggedTemplateExpression>, state) {
         try {
           const tag = path.get('tag');
           if (isLocalize(tag, localizeName)) {
@@ -40,7 +40,7 @@ export function makeEs2015TranslatePlugin(
             // If we get a BabelParseError here then something went wrong with Babel itself
             // since there must be something wrong with the structure of the AST generated
             // by Babel parsing a TaggedTemplateExpression.
-            throw buildCodeFrameError(fs, path, e);
+            throw buildCodeFrameError(fs, path, state.file, e);
           } else {
             throw e;
           }

packages/localize/tools/src/translate/source_files/es5_translate_plugin.ts

@@ -24,7 +24,7 @@ export function makeEs5TranslatePlugin(
     fs: PathManipulation = getFileSystem()): PluginObj {
   return {
     visitor: {
-      CallExpression(callPath: NodePath<t.CallExpression>) {
+      CallExpression(callPath: NodePath<t.CallExpression>, state) {
         try {
           const calleePath = callPath.get('callee');
           if (isLocalize(calleePath, localizeName)) {
@@ -36,7 +36,7 @@ export function makeEs5TranslatePlugin(
           }
         } catch (e) {
           if (isBabelParseError(e)) {
-            diagnostics.error(buildCodeFrameError(fs, callPath, e));
+            diagnostics.error(buildCodeFrameError(fs, callPath, state.file, e));
           } else {
             throw e;
           }