Preserve top-level 'use server' directives like 'use client' dire…

…ctives

.changeset/silly-weeks-sparkle.md

@@ -0,0 +1,5 @@
+---
+"@preconstruct/cli": patch
+---
+
+Top-level `'use server'` directives are now also preserved like `'use client'` directives.

packages/cli/src/build/__tests__/other.ts

@@ -1558,3 +1558,89 @@ test("simple use client with comment above directive", async () => {
 
   `);
 });
+
+test("use server", async () => {
+  const dir = await testdir({
+    "package.json": JSON.stringify({
+      name: "pkg",
+      main: "dist/pkg.cjs.js",
+      module: "dist/pkg.esm.js",
+    }),
+    "src/index.js": js`
+      export { doSomething } from "./server";
+    `,
+    "src/server.js": js`
+      "use server";
+      export function doSomething() {}
+    `,
+  });
+  await build(dir);
+  expect(await getFiles(dir, ["dist/**"], stripHashes("server")))
+    .toMatchInlineSnapshot(`
+    ⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯ dist/pkg.cjs.dev.js ⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯
+    'use strict';
+
+    Object.defineProperty(exports, '__esModule', { value: true });
+
+    var server = require('./server-some-hash.cjs.dev.js');
+
+
+
+    Object.defineProperty(exports, 'doSomething', {
+    	enumerable: true,
+    	get: function () { return server.doSomething; }
+    });
+
+    ⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯ dist/pkg.cjs.js ⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯
+    'use strict';
+
+    if (process.env.NODE_ENV === "production") {
+      module.exports = require("./pkg.cjs.prod.js");
+    } else {
+      module.exports = require("./pkg.cjs.dev.js");
+    }
+
+    ⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯ dist/pkg.cjs.prod.js ⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯
+    'use strict';
+
+    Object.defineProperty(exports, '__esModule', { value: true });
+
+    var server = require('./server-some-hash.cjs.prod.js');
+
+
+
+    Object.defineProperty(exports, 'doSomething', {
+    	enumerable: true,
+    	get: function () { return server.doSomething; }
+    });
+
+    ⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯ dist/pkg.esm.js ⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯
+    export { doSomething } from './server-some-hash.esm.js';
+
+    ⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯ dist/server-this-is-not-the-real-hash-288a9f5076a34272a0270a4055aa266d.esm.js ⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯
+    'use server';
+    function doSomething() {}
+
+    export { doSomething };
+
+    ⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯ dist/server-this-is-not-the-real-hash-4c6b8ec0a8b072aff1b26a3ac24de144.cjs.js ⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯
+    'use strict';
+
+    if (process.env.NODE_ENV === "production") {
+      module.exports = require("./server-some-hash.cjs.prod.js");
+    } else {
+      module.exports = require("./server-some-hash.cjs.dev.js");
+    }
+
+    ⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯ dist/server-this-is-not-the-real-hash-f9ea3f80de7afbb1e4ac2175565ef521.cjs.dev.js, dist/server-this-is-not-the-real-hash-f9ea3f80de7afbb1e4ac2175565ef521.cjs.prod.js ⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯
+    'use server';
+    'use strict';
+
+    Object.defineProperty(exports, '__esModule', { value: true });
+
+    function doSomething() {}
+
+    exports.doSomething = doSomething;
+
+  `);
+});

packages/cli/src/rollup-plugins/server-components.ts

@@ -21,15 +21,15 @@ export function serverComponentsPlugin({
       }
       const loaded = await this.load(resolved);
       if (
-        typeof loaded.meta.useClientReferenceId === "string" &&
+        typeof loaded.meta.directivePreservedFile?.referenceId === "string" &&
         importer !== undefined
       ) {
         // this name is appended for Rollup naming chunks/variables in the output
         const name = path
           .basename(resolved.id)
           .replace(/\.[tj]sx?$/, "")
           .replace(/[^\w]/g, "_");
-        const id = `__USE_CLIENT_IMPORT__${loaded.meta.useClientReferenceId}__USE_CLIENT_IMPORT__/${name}`;
+        const id = `__USE_CLIENT_IMPORT__${loaded.meta.directivePreservedFile.referenceId}__USE_CLIENT_IMPORT__/${name}`;
 
         return {
           id,
@@ -41,35 +41,35 @@ export function serverComponentsPlugin({
     transform(code, id) {
       if (id.startsWith("\0")) return null;
       const directives = getModuleDirectives(code);
-      const useClientDirective = directives.find(
-        (d) => d.value === "use client"
+      const directive = directives.find(
+        (d) => d.value === "use client" || d.value === "use server"
       );
-      if (useClientDirective) {
-        const magicString = new MagicString(code);
-        const referenceId = this.emitFile({
-          type: "chunk",
-          id,
-          preserveSignature: "allow-extension",
-        });
-        magicString.remove(useClientDirective.start, useClientDirective.end);
-        return {
-          code: magicString.toString(),
-          map: sourceMap
-            ? (magicString.generateMap({ hires: true }) as SourceMapInput)
-            : undefined,
-          meta: {
-            useClientReferenceId: referenceId,
-          },
-        };
-      }
-      return null;
+      if (!directive) return null;
+      const magicString = new MagicString(code);
+      const referenceId = this.emitFile({
+        type: "chunk",
+        id,
+        preserveSignature: "allow-extension",
+      });
+      magicString.remove(directive.start, directive.end);
+      return {
+        code: magicString.toString(),
+        map: sourceMap
+          ? (magicString.generateMap({ hires: true }) as SourceMapInput)
+          : undefined,
+        meta: {
+          directivePreservedFile: { referenceId, directive: directive.value },
+        },
+      };
     },
     renderChunk(code, chunk) {
       const magicString = new MagicString(code);
       if (chunk.facadeModuleId !== null) {
         const moduleInfo = this.getModuleInfo(chunk.facadeModuleId);
-        if (moduleInfo?.meta.useClientReferenceId) {
-          magicString.prepend("'use client';\n");
+        if (moduleInfo?.meta.directivePreservedFile) {
+          const directive: "use client" | "use server" =
+            moduleInfo?.meta.directivePreservedFile.directive;
+          magicString.prepend(`'${directive}';\n`);
         }
       }
 

packages/cli/src/rollup-plugins/typescript-declarations/index.ts

@@ -100,7 +100,7 @@ export default function typescriptDeclarations(pkg: Package): Plugin {
           const moduleInfo = this.getModuleInfo(file.facadeModuleId);
           // this will happen for "use client" modules where it's not
           // an actual entrypoint but it is a Rollup entry
-          if (moduleInfo?.meta.useClientReferenceId) {
+          if (moduleInfo?.meta.directivePreservedFile) {
             continue;
           }
           // otherwise, a user should never be able to cause this to happen