Support submodules in autoloader

PR-URL: #1888

lib/deps.js

@@ -44,11 +44,31 @@ const loadPlugins = (lib) => {
   }
 };
 
+const validSubmodules = (key) =>
+  key !== '' && !key.includes('*') && !key.includes('.');
+
+const loadModule = (name) => {
+  const lib = appRequire(name);
+  const pkg = require(`${CWD}/node_modules/${name}/package.json`);
+  if (!pkg.exports) return lib;
+  const subKeys = Object.keys(pkg.exports).map((key) => key.substring(2));
+  const subNames = subKeys.filter(validSubmodules);
+  for (const subName of subNames) {
+    const sub = appRequire(name + '/' + subName);
+    lib[subName] = sub;
+  }
+  return lib;
+};
+
 for (const name of dependencies) {
   if (name === 'impress') continue;
   let lib = null;
   try {
-    lib = internals.includes(name) ? require(`node:${name}`) : appRequire(name);
+    if (internals.includes(name)) {
+      lib = require(`node:${name}`);
+    } else {
+      lib = loadModule(name);
+    }
   } catch {
     if (npmpkg.includes(name) || !optional.includes(name)) {
       notLoaded.add(name);