From dda7c59b04da82f9be4faedf0d937d8ef6a96e7c Mon Sep 17 00:00:00 2001
From: LeoTM <1881059+leotm@users.noreply.github.com>
Date: Mon, 30 Sep 2024 17:19:50 +0100
Subject: [PATCH] feat(ses): bundle and export shim compatible with Hermes
 compiler

---
 packages/ses/package.json      |  8 +++--
 packages/ses/scripts/bundle.js | 65 ++++++++++++++++++++++++----------
 2 files changed, 53 insertions(+), 20 deletions(-)

diff --git a/packages/ses/package.json b/packages/ses/package.json
index 6e5bf418c6..e3eb14efa8 100644
--- a/packages/ses/package.json
+++ b/packages/ses/package.json
@@ -42,8 +42,10 @@
       },
       "require": {
         "types": "./dist/types.d.cts",
+        "hermes": "./dist/ses-hermes.cjs",
         "default": "./dist/ses.cjs"
-      }
+      },
+      "default": "./src/index.js"
     },
     "./lockdown": {
       "import": {
@@ -63,7 +65,9 @@
     "./package.json": "./package.json"
   },
   "scripts": {
-    "build": "node scripts/bundle.js",
+    "build:vanilla": "node scripts/bundle.js",
+    "build:hermes": "SES_BUILD_TYPE=hermes node scripts/bundle.js",
+    "build": "yarn build:vanilla && yarn build:hermes",
     "clean": "rm -rf dist",
     "cover": "c8 ava",
     "demo": "python3 -m http.server",
diff --git a/packages/ses/scripts/bundle.js b/packages/ses/scripts/bundle.js
index 9b330299f1..c275fdd286 100644
--- a/packages/ses/scripts/bundle.js
+++ b/packages/ses/scripts/bundle.js
@@ -1,9 +1,13 @@
+/** @import {ModuleTransforms} from '../../compartment-mapper/types.js' */
+
 /* global process */
 import '../index.js';
 import fs from 'fs';
 import { makeBundle } from '@endo/compartment-mapper/bundle.js';
 import { minify } from 'terser';
 import { fileURLToPath, pathToFileURL } from 'url';
+import { getEnvironmentOption as getenv } from '@endo/env-options';
+import { hermesTransforms } from './hermes-transforms.js';
 
 lockdown();
 
@@ -16,7 +20,11 @@ const write = async (target, content) => {
   await fs.promises.writeFile(location, content);
 };
 
-const main = async () => {
+/**
+ * @param {object} [options]
+ * @param {string} [options.buildType] Suffix used to build special bundles (e.g. 'hermes')
+ */
+const writeBundle = async ({ buildType } = {}) => {
   const text = await fs.promises.readFile(
     fileURLToPath(`${root}/package.json`),
     'utf8',
@@ -24,32 +32,48 @@ const main = async () => {
   const packageJson = JSON.parse(text);
   const version = packageJson.version;
 
+  /** @type ModuleTransforms */
+  const moduleTransforms = {};
+
+  let bundleFilePaths = [
+    'dist/ses.cjs',
+    'dist/ses.mjs',
+    'dist/ses.umd.js',
+    'dist/lockdown.cjs',
+    'dist/lockdown.mjs',
+    'dist/lockdown.umd.js',
+  ];
+  let terseFilePaths = ['dist/ses.umd.min.js', 'dist/lockdown.umd.min.js'];
+
+  if (buildType === 'hermes') {
+    bundleFilePaths = ['dist/ses-hermes.cjs'];
+    terseFilePaths = [];
+    Object.assign(moduleTransforms, hermesTransforms);
+  }
+
   const bundle = await makeBundle(
     read,
     pathToFileURL(resolve('../index.js', import.meta.url)).toString(),
+    { moduleTransforms },
   );
   const versionedBundle = `// ses@${version}\n${bundle}`;
 
-  const { code: terse } = await minify(versionedBundle, {
-    mangle: false,
-    keep_classnames: true,
-  });
-  assert.string(terse);
-
+  console.log(`-- Building '${buildType}' version of SES --`);
   console.log(`Bundle size: ${versionedBundle.length} bytes`);
-  console.log(`Minified bundle size: ${terse.length} bytes`);
 
-  await fs.promises.mkdir('dist', { recursive: true });
+  /** @type {string|undefined} */
+  let terse;
+  if (terseFilePaths.length) {
+    const { code } = await minify(versionedBundle, {
+      mangle: false,
+      keep_classnames: true,
+    });
+    terse = code;
+    assert.string(terse);
+    console.log(`Minified bundle size: ${terse.length} bytes`);
+  }
 
-  const bundleFilePaths = [
-    'dist/ses.cjs',
-    'dist/ses.mjs',
-    'dist/ses.umd.js',
-    'dist/lockdown.cjs',
-    'dist/lockdown.mjs',
-    'dist/lockdown.umd.js',
-  ];
-  const terseFilePaths = ['dist/ses.umd.min.js', 'dist/lockdown.umd.min.js'];
+  await fs.promises.mkdir('dist', { recursive: true });
 
   await Promise.all([
     ...bundleFilePaths.map(dest => write(dest, versionedBundle)),
@@ -82,6 +106,11 @@ const main = async () => {
   console.log(`Copied ${sourceDTS} to ${destDTS}`);
 };
 
+const main = async () => {
+  const buildType = getenv('SES_BUILD_TYPE', 'vanilla');
+  await writeBundle({ buildType });
+};
+
 main().catch(err => {
   console.error('Error running main:', err);
   process.exitCode = 1;