fix(astro): resolve Astro's private APIs properly

Author: AriPerkkio

packages/astro/src/default/layouts/Layout.astro

@@ -38,7 +38,8 @@ const baseURL = import.meta.env.BASE_URL;
       }
     </script>
     <script>
-      import * as builtInSwap from 'node_modules/astro/dist/transitions/swap-functions';
+      // @ts-ignore -- untyped
+      import * as builtInSwap from 'tutorialkit:astro-swap-functions';
 
       declare global {
         function setTutorialKitTheme(): void;

packages/astro/src/index.ts

@@ -4,6 +4,7 @@ import { fileURLToPath } from 'node:url';
 import { extraIntegrations } from './integrations.js';
 import { updateMarkdownConfig } from './remark/index.js';
 import { tutorialkitCore } from './vite-plugins/core.js';
+import { astroSwapFunctions } from './vite-plugins/astro-swap-functions.js';
 import { userlandCSS, watchUserlandCSS } from './vite-plugins/css.js';
 import { tutorialkitStore } from './vite-plugins/store.js';
 import { overrideComponents, type OverrideComponentsOptions } from './vite-plugins/override-components.js';
@@ -108,6 +109,7 @@ export default function createPlugin({
               tutorialkitStore,
               tutorialkitCore,
               overrideComponents({ components, defaultRoutes: !!defaultRoutes }),
+              astroSwapFunctions(),
               process.env.TUTORIALKIT_DEV ? (await import('vite-plugin-inspect')).default() : null,
             ],
           },

packages/astro/src/vite-plugins/astro-swap-functions.ts

@@ -0,0 +1,36 @@
+/**
+ * A plugin for importing Astro's private 'transitions/swap-functions.js' module.
+ * This is temporary solution and can break at any time when end-user's update their `astro` version.
+ */
+import { readFile } from 'node:fs/promises';
+import { createRequire } from 'node:module';
+import { resolve } from 'node:path';
+import type { VitePlugin } from '../types.js';
+
+const require = createRequire(import.meta.url);
+const astroDist = resolve(require.resolve('astro/package.json'), '..');
+const swapFunctionEntry = resolve(astroDist, 'dist/transitions/swap-functions.js');
+
+const virtualModuleId = 'tutorialkit:astro-swap-functions';
+const resolvedId = `\0${virtualModuleId}`;
+
+export function astroSwapFunctions(): VitePlugin {
+  return {
+    name: 'tutorialkit-astro-swap-functions-plugin',
+    resolveId(id) {
+      if (id === virtualModuleId) {
+        return resolvedId;
+      }
+
+      return undefined;
+    },
+
+    async load(id) {
+      if (id === resolvedId) {
+        return await readFile(swapFunctionEntry, 'utf8');
+      }
+
+      return undefined;
+    },
+  };
+}