Make sure that Rollup's dynamicRequireTargets are included

.yarn/patches/@rollup__plugin-commonjs.patch

@@ -0,0 +1,15 @@
+See packages/babel-standalone/src/dynamic-require-entrypoint.cjs for the reason for this diff.
+
+diff --git a/dist/index.js b/dist/index.js
+index 712f6a7d81b115d468a764b4139caa00d6cfc358..73fbf004217f3d44b6420d3082a0846b53e00f4c 100644
+--- a/dist/index.js
++++ b/dist/index.js
+@@ -1626,7 +1626,7 @@ function commonjs(options = {}) {
+   const sourceMap = options.sourceMap !== false;
+
+   function transformAndCheckExports(code, id) {
+-    if (isDynamicRequireModulesEnabled && this.getModuleInfo(id).isEntry) {
++    if (isDynamicRequireModulesEnabled && (this.getModuleInfo(id).isEntry || id.endsWith("/dynamic-require-entrypoint.cjs"))) {
+       code =
+         getDynamicPackagesEntryIntro(dynamicRequireModuleDirPaths, dynamicRequireModuleSet) + code;
+     }

Gulpfile.mjs

@@ -245,8 +245,8 @@ function resolveChain(baseUrl, ...packages) {
 
   return packages.reduce(
     (base, pkg) =>
-      require.resolve(pkg + "/package.json", { paths: [path.dirname(base)] }),
-    fileURLToPath(baseUrl)
+      path.dirname(require.resolve(pkg + "/package.json", { paths: [base] })),
+    path.dirname(fileURLToPath(baseUrl))
   );
 }
 
@@ -304,6 +304,8 @@ function buildRollup(packages, targetBrowsers) {
               // Rollup doesn't read export maps, so it loads the cjs fallback
               "packages/babel-compat-data/*.js",
               "packages/*/src/**/*.cjs",
+              // See the comment in this file for the reason to include it
+              "packages/babel-standalone/src/dynamic-require-entrypoint.cjs",
             ],
             dynamicRequireTargets: [
               // https://github.com/mathiasbynens/regexpu-core/blob/ffd8fff2e31f4597f6fdfee75d5ac1c5c8111ec3/rewrite-pattern.js#L48
@@ -312,7 +314,7 @@ function buildRollup(packages, targetBrowsers) {
                 "./packages/babel-helper-create-regexp-features-plugin",
                 "regexpu-core",
                 "regenerate-unicode-properties"
-              ) + "/../**",
+              ) + "/**/*.js",
             ],
           }),
           rollupBabel({

package.json

@@ -32,7 +32,7 @@
     "@babel/register": "^7.12.0",
     "@babel/runtime": "^7.12.0",
     "@rollup/plugin-babel": "^5.2.0",
-    "@rollup/plugin-commonjs": "^17.1.0",
+    "@rollup/plugin-commonjs": "patch:@rollup/plugin-commonjs@^17.1.0#./.yarn/patches/@rollup__plugin-commonjs.patch",
     "@rollup/plugin-json": "^4.1.0",
     "@rollup/plugin-node-resolve": "^9.0.0",
     "@rollup/plugin-replace": "^2.3.3",

packages/babel-standalone/src/dynamic-require-entrypoint.cjs

@@ -0,0 +1,13 @@
+/*
+We bundle @babel/standalone using the dynamicRequireTargets option.
+This option needs to inject requrie() calls to all the modules that
+could be dynamically required later.
+
+By default it injects them in the entrypoint, but when rollup loads the
+entrypoint it finds syntax that it doesn't support (because
+@rollup/plugin-commonjs must run before @rollup/plugin-babel).
+
+We use "yarn patch" to modify the @rollup/plugin-commonjs package, so
+that it injects those "preload" require() calls in this file rather
+than in the entrypoint.
+*/

packages/babel-standalone/src/index.js

@@ -10,6 +10,9 @@
 /* global VERSION */
 /* eslint-disable max-len */
 
+// $FlowIgnore
+import "./dynamic-require-entrypoint.cjs";
+
 import {
   transformFromAst as babelTransformFromAst,
   transform as babelTransform,

yarn.lock

@@ -3703,7 +3703,7 @@ __metadata:
   languageName: node
   linkType: hard
 
-"@rollup/plugin-commonjs@npm:^17.1.0":
+"@rollup/plugin-commonjs@^17.1.0":
   version: 17.1.0
   resolution: "@rollup/plugin-commonjs@npm:17.1.0"
   dependencies:
@@ -3720,6 +3720,23 @@ __metadata:
   languageName: node
   linkType: hard
 
+"@rollup/plugin-commonjs@patch:@rollup/plugin-commonjs@^17.1.0#./.yarn/patches/@rollup__plugin-commonjs.patch::locator=babel%40workspace%3A.":
+  version: 17.1.0
+  resolution: "@rollup/plugin-commonjs@patch:@rollup/plugin-commonjs@npm%3A17.1.0#./.yarn/patches/@rollup__plugin-commonjs.patch::version=17.1.0&hash=a0d076&locator=babel%40workspace%3A."
+  dependencies:
+    "@rollup/pluginutils": ^3.1.0
+    commondir: ^1.0.1
+    estree-walker: ^2.0.1
+    glob: ^7.1.6
+    is-reference: ^1.2.1
+    magic-string: ^0.25.7
+    resolve: ^1.17.0
+  peerDependencies:
+    rollup: ^2.30.0
+  checksum: ccf44f300b5b7b9fcc72e22c414bd86ce461e412a0980fb2f73d6d2b562466409ecaae270a54028c4584650c7d1a0718a6af0d15c5a5b41d6cd20a2159ba34fb
+  languageName: node
+  linkType: hard
+
 "@rollup/plugin-json@npm:^4.1.0":
   version: 4.1.0
   resolution: "@rollup/plugin-json@npm:4.1.0"
@@ -4857,7 +4874,7 @@ __metadata:
     "@babel/register": ^7.12.0
     "@babel/runtime": ^7.12.0
     "@rollup/plugin-babel": ^5.2.0
-    "@rollup/plugin-commonjs": ^17.1.0
+    "@rollup/plugin-commonjs": "patch:@rollup/plugin-commonjs@^17.1.0#./.yarn/patches/@rollup__plugin-commonjs.patch"
     "@rollup/plugin-json": ^4.1.0
     "@rollup/plugin-node-resolve": ^9.0.0
     "@rollup/plugin-replace": ^2.3.3