Use swc / ts-node instead of babel

.gitignore

@@ -33,4 +33,6 @@ package.tgz
 # We check-in the PnP hook because it would be heavy to regenerate it before each bundle build
 !/packages/yarnpkg-pnp/lib/hook.js
 
-/vscode-case-study
+/vscode-case-study
+
+/.typescript-cached-transpile

.yarn/versions/9cc4141b.yml

@@ -0,0 +1,30 @@
+declined:
+  - "@yarnpkg/plugin-compat"
+  - "@yarnpkg/plugin-constraints"
+  - "@yarnpkg/plugin-dlx"
+  - "@yarnpkg/plugin-essentials"
+  - "@yarnpkg/plugin-exec"
+  - "@yarnpkg/plugin-file"
+  - "@yarnpkg/plugin-git"
+  - "@yarnpkg/plugin-github"
+  - "@yarnpkg/plugin-http"
+  - "@yarnpkg/plugin-interactive-tools"
+  - "@yarnpkg/plugin-link"
+  - "@yarnpkg/plugin-node-modules"
+  - "@yarnpkg/plugin-npm"
+  - "@yarnpkg/plugin-npm-cli"
+  - "@yarnpkg/plugin-pack"
+  - "@yarnpkg/plugin-patch"
+  - "@yarnpkg/plugin-pnp"
+  - "@yarnpkg/plugin-stage"
+  - "@yarnpkg/plugin-typescript"
+  - "@yarnpkg/plugin-version"
+  - "@yarnpkg/plugin-workspace-tools"
+  - "@yarnpkg/builder"
+  - "@yarnpkg/cli"
+  - "@yarnpkg/core"
+  - "@yarnpkg/fslib"
+  - "@yarnpkg/libui"
+  - "@yarnpkg/pnp"
+  - "@yarnpkg/pnpify"
+  - "@yarnpkg/shell"

.yarnrc.yml

@@ -53,6 +53,12 @@ packageExtensions:
         optional: true
       typedoc-plugin-yarn:
         optional: true
+  "@node-rs/helper@*":
+    dependencies:
+      "@swc/core-linux": "*"
+      "@swc/core-linux-musl": "*"
+      "@swc/core-darwin": "*"
+      "@swc/core-win32": "*"
 
 preferInteractive: true
 

package.json

@@ -19,6 +19,7 @@
     "@babel/preset-react": "^7.10.1",
     "@babel/preset-typescript": "^7.10.1",
     "@babel/register": "^7.10.1",
+    "@swc/core": "^1.2.40",
     "@types/emscripten": "^1.38.0",
     "@types/jest": "^24.0.25",
     "@types/node": "^13.7.0",
@@ -38,8 +39,10 @@
     "jest-environment-node": "^26.0.1",
     "jest-junit": "^10.0.0",
     "micromatch": "^4.0.2",
+    "ts-node": "github:TypeStrong/ts-node#ab/swc-compiler",
     "tslib": "^1.13.0",
-    "typescript": "4.1.0-beta"
+    "typescript": "4.1.0-beta",
+    "typescript-cached-transpile": "^0.0.6"
   },
   "resolutions": {
     "yoga-layout-prebuilt": "patch:yoga-layout-prebuilt@1.10.0#./.yarn/patches/yoga-layout-prebuilt.patch"

packages/acceptance-tests/pkg-tests-core/sources/utils/fs.ts

@@ -3,7 +3,7 @@ import {stringifySyml, parseSyml}                  from '@yarnpkg/parsers';
 import klaw                                        from 'klaw';
 import tarFs                                       from 'tar-fs';
 import zlib                                        from 'zlib';
-import {Gzip}                                      from 'zlib';
+import type {Gzip}                                 from 'zlib';
 
 import * as miscUtils                              from './misc';
 

packages/acceptance-tests/pkg-tests-core/sources/utils/makeTemporaryMonorepoEnv.ts

@@ -1,7 +1,7 @@
 import {PortablePath, ppath, Filename} from '@yarnpkg/fslib';
 
 import * as fsUtils                    from './fs';
-import {RunFunction}                   from './tests';
+import type {RunFunction}              from './tests';
 
 const deepResolve = require(`super-resolve`);
 

packages/acceptance-tests/pkg-tests-core/sources/utils/tests.ts

@@ -1,25 +1,25 @@
-import {PortablePath, npath, toFilename} from '@yarnpkg/fslib';
-import crypto                            from 'crypto';
-import finalhandler                      from 'finalhandler';
-import https                             from 'https';
-import http                              from 'http';
-
-import {IncomingMessage, ServerResponse} from 'http';
-import invariant                         from 'invariant';
-import {AddressInfo}                     from 'net';
-import pem                               from 'pem';
-import semver                            from 'semver';
-import serveStatic                       from 'serve-static';
-import {promisify}                       from 'util';
+import {PortablePath, npath, toFilename}      from '@yarnpkg/fslib';
+import crypto                                 from 'crypto';
+import finalhandler                           from 'finalhandler';
+import https                                  from 'https';
+import http                                   from 'http';
+
+import type {IncomingMessage, ServerResponse} from 'http';
+import invariant                              from 'invariant';
+import type {AddressInfo}                     from 'net';
+import pem                                    from 'pem';
+import semver                                 from 'semver';
+import serveStatic                            from 'serve-static';
+import {promisify}                            from 'util';
 
 const deepResolve = require(`super-resolve`);
 
 const staticServer = serveStatic(npath.fromPortablePath(require(`pkg-tests-fixtures`)));
 
-import {Gzip}       from 'zlib';
+import type {Gzip}       from 'zlib';
 
-import {ExecResult} from './exec';
-import * as fsUtils from './fs';
+import type {ExecResult} from './exec';
+import * as fsUtils      from './fs';
 
 export type PackageEntry = Map<string, {path: string, packageJson: Object}>;
 export type PackageRegistry = Map<string, PackageEntry>;

packages/acceptance-tests/pkg-tests-specs/sources/plugins/plugin-typescript.test.ts

@@ -1,7 +1,7 @@
-import {Manifest}     from '@yarnpkg/core';
-import {PortablePath} from '@yarnpkg/fslib';
-import {merge}        from 'lodash';
-import {fs, yarn}     from 'pkg-tests-core';
+import {Manifest}          from '@yarnpkg/core';
+import type {PortablePath} from '@yarnpkg/fslib';
+import {merge}             from 'lodash';
+import {fs, yarn}          from 'pkg-tests-core';
 
 const {unpackToDirectory} = fs;
 const {writeConfiguration, readManifest} = yarn;

packages/acceptance-tests/pkg-tests-specs/sources/protocols/workspace.test.ts

@@ -1,5 +1,5 @@
-import {PortablePath} from '@yarnpkg/fslib';
-import {fs}           from 'pkg-tests-core';
+import type {PortablePath} from '@yarnpkg/fslib';
+import {fs}                from 'pkg-tests-core';
 
 const {writeJson} = fs;
 

packages/acceptance-tests/pkg-tests-specs/sources/workspace.test.ts

@@ -1,6 +1,6 @@
-import {PortablePath} from '@yarnpkg/fslib';
-import {exec}         from 'pkg-tests-core';
-import {fs}           from 'pkg-tests-core';
+import type {PortablePath} from '@yarnpkg/fslib';
+import type {exec}         from 'pkg-tests-core';
+import {fs}                from 'pkg-tests-core';
 
 const {readFile, writeFile, writeJson} = fs;
 

packages/gatsby/src/components/seo.tsx

@@ -10,7 +10,7 @@ import Helmet                    from 'react-helmet';
 import React                     from 'react';
 
 import yarnKittenFull            from '../images/yarn-kitten-full.svg';
-import {Query}                   from '../types/queries';
+import type {Query}                   from '../types/queries';
 
 export const defaultKeywords = [`package manager`, `yarn`, `yarnpkg`, `configuration`, `yarnrc`];
 

packages/plugin-compat/sources/extensions.ts

@@ -2,7 +2,7 @@
 // the same fields as you add here and prefix your changes with the relevant
 // PR url.
 
-import {PackageExtensionData} from '@yarnpkg/core';
+import type {PackageExtensionData} from '@yarnpkg/core';
 
 const optionalPeerDep = {
   optional: true,

packages/plugin-compat/sources/index.ts

@@ -1,5 +1,5 @@
 import {Hooks as CoreHooks, Plugin, structUtils} from '@yarnpkg/core';
-import {Hooks as PatchHooks}                     from '@yarnpkg/plugin-patch';
+import type {Hooks as PatchHooks}                from '@yarnpkg/plugin-patch';
 
 import {packageExtensions}                       from './extensions';
 import {getPatch as getFseventsPatch}            from './patches/fsevents.patch';

packages/plugin-constraints/sources/index.ts

@@ -1,5 +1,5 @@
 import {Plugin, SettingsType} from '@yarnpkg/core';
-import {PortablePath}         from '@yarnpkg/fslib';
+import type {PortablePath}    from '@yarnpkg/fslib';
 
 import queryConstraints       from './commands/constraints/query';
 import sourceConstraints      from './commands/constraints/source';

packages/plugin-constraints/sources/tauModule.ts

@@ -1,7 +1,7 @@
 /// <reference path="./tauProlog.d.ts"/>
 
 import {Project, structUtils} from '@yarnpkg/core';
-import {PortablePath}         from '@yarnpkg/fslib';
+import type {PortablePath}    from '@yarnpkg/fslib';
 import getPath                from 'lodash/get';
 import pl                     from 'tau-prolog';
 import vm                     from 'vm';

packages/plugin-dlx/sources/index.ts

@@ -1,7 +1,7 @@
-import {Plugin} from '@yarnpkg/core';
+import type {Plugin} from '@yarnpkg/core';
 
-import create   from './commands/create';
-import dlx      from './commands/dlx';
+import create        from './commands/create';
+import dlx           from './commands/dlx';
 
 const plugin: Plugin = {
   commands: [