test(rsc): copy use cache/server mixed directive handling to examples/use-cache-persistent

packages/plugin-rsc/examples/use-cache-persistent/callable-cache-plugin.ts

@@ -54,7 +54,7 @@ export function callableCachePlugin(): Plugin {
             ]),
           }
           return (
-            `$$ReactServer.registerServerReference(` +
+            `$$CacheReactServer.registerServerReference(` +
             `$$cacheWrapper(${value}, ${JSON.stringify(options)}),` +
             `${JSON.stringify(reference.referenceKey)},` +
             `${JSON.stringify(name)})`
@@ -68,6 +68,9 @@ export function callableCachePlugin(): Plugin {
               // and viewport exports.
               // https://github.com/vercel/next.js/blob/aae4179ac628e55483b62cd023a7e1827dcef122/crates/next-custom-transforms/src/transforms/server_actions.rs#L1914-L1919
               filter: (_name, meta) =>
+                // Inline "use server" overrides the file-level cache role and
+                // is left for the built-in transform.
+                !hasFunctionDirective(meta, 'use server') &&
                 meta.valueNode?.type !== 'ObjectExpression' &&
                 meta.valueNode?.type !== 'ArrayExpression',
               rejectNonAsyncFunction: true,
@@ -93,9 +96,14 @@ export function callableCachePlugin(): Plugin {
           exportNames: 'names' in result ? result.names : result.exportNames,
         })
         cacheModules.add(id)
-        result.output.prepend(
+        // Preserve leading directives so a later transform can still recognize
+        // a file-level role such as "use server".
+        const importPosition =
+          ast.body.find((node) => !('directive' in node))?.start ?? code.length
+        result.output.prependLeft(
+          importPosition,
           `import $$cacheWrapper, { encryptCacheCaptures as $$encryptCacheCaptures } from "/src/framework/use-cache-runtime";\n` +
-            `import * as $$ReactServer from "@vitejs/plugin-rsc/react/rsc/server";\n`,
+            `import * as $$CacheReactServer from "@vitejs/plugin-rsc/react/rsc/server";\n`,
         )
         return {
           code: result.output.toString(),
@@ -111,12 +119,12 @@ export function callableCachePlugin(): Plugin {
           meta.valueNode?.type !== 'ArrayExpression',
         rejectNonAsyncFunction: true,
         runtime: (name) =>
-          `$$ReactClient.createServerReference(` +
+          `$$CacheReactClient.createServerReference(` +
           `${JSON.stringify(reference.referenceKey + '#' + name)},` +
-          `$$ReactClient.callServer,` +
+          `$$CacheReactClient.callServer,` +
           `undefined,` +
           (this.environment.mode === 'dev'
-            ? `$$ReactClient.findSourceMapURL,`
+            ? `$$CacheReactClient.findSourceMapURL,`
             : `undefined,`) +
           `${JSON.stringify(name)})`,
       })
@@ -132,7 +140,7 @@ export function callableCachePlugin(): Plugin {
       const runtimeEnvironment =
         environmentName === 'client' ? 'browser' : 'ssr'
       result.output.prepend(
-        `import * as $$ReactClient from "@vitejs/plugin-rsc/react/${runtimeEnvironment}";\n`,
+        `import * as $$CacheReactClient from "@vitejs/plugin-rsc/react/${runtimeEnvironment}";\n`,
       )
       return {
         code: result.output.toString(),
@@ -151,6 +159,27 @@ export function callableCachePlugin(): Plugin {
   }
 }
 
+function hasFunctionDirective(
+  meta: Pick<ModuleExportMeta, 'valueNode'>,
+  directive: string,
+): boolean {
+  const node = meta.valueNode
+  if (
+    (node?.type !== 'FunctionDeclaration' &&
+      node?.type !== 'FunctionExpression' &&
+      node?.type !== 'ArrowFunctionExpression') ||
+    node.body.type !== 'BlockStatement'
+  ) {
+    return false
+  }
+  return node.body.body.some(
+    (statement) =>
+      statement.type === 'ExpressionStatement' &&
+      'directive' in statement &&
+      statement.directive === directive,
+  )
+}
+
 function getCacheWrapperOptions(
   meta: Pick<ModuleExportMeta, 'valueNode'>,
 ): Pick<CacheWrapperOptions, 'argumentCount'> {