vercel · unstubbable · Nov 13, 2024 · Nov 13, 2024
diff --git a/crates/next-core/src/next_client/transforms.rs b/crates/next-core/src/next_client/transforms.rs
@@ -47,6 +47,12 @@ pub async fn get_next_client_transforms_rules(
         rules.push(get_debug_fn_name_rule(enable_mdx_rs));
     }
 
+    let dynamic_io_enabled = next_config
+        .experimental()
+        .await?
+        .dynamic_io
+        .unwrap_or(false);
+
     let mut is_app_dir = false;
 
     match context_ty {
@@ -72,6 +78,7 @@ pub async fn get_next_client_transforms_rules(
             rules.push(get_server_actions_transform_rule(
                 ActionsTransform::Client,
                 enable_mdx_rs,
+                dynamic_io_enabled,
             ));
         }
         ClientContextType::Fallback | ClientContextType::Other => {}

diff --git a/crates/next-core/src/next_server/transforms.rs b/crates/next-core/src/next_server/transforms.rs
@@ -54,6 +54,12 @@ pub async fn get_next_server_transforms_rules(
         ));
     }
 
+    let dynamic_io_enabled = next_config
+        .experimental()
+        .await?
+        .dynamic_io
+        .unwrap_or(false);
+
     let mut is_app_dir = false;
 
     let is_server_components = match context_ty {
@@ -89,6 +95,7 @@ pub async fn get_next_server_transforms_rules(
             rules.push(get_server_actions_transform_rule(
                 ActionsTransform::Client,
                 mdx_rs,
+                dynamic_io_enabled,
             ));
 
             is_app_dir = true;
@@ -99,6 +106,7 @@ pub async fn get_next_server_transforms_rules(
             rules.push(get_server_actions_transform_rule(
                 ActionsTransform::Server,
                 mdx_rs,
+                dynamic_io_enabled,
             ));
 
             is_app_dir = true;
@@ -109,6 +117,7 @@ pub async fn get_next_server_transforms_rules(
             rules.push(get_server_actions_transform_rule(
                 ActionsTransform::Server,
                 mdx_rs,
+                dynamic_io_enabled,
             ));
 
             is_app_dir = true;

diff --git a/crates/next-core/src/next_shared/transforms/server_actions.rs b/crates/next-core/src/next_shared/transforms/server_actions.rs
@@ -18,9 +18,12 @@ pub enum ActionsTransform {
 pub fn get_server_actions_transform_rule(
     transform: ActionsTransform,
     enable_mdx_rs: bool,
+    dynamic_io_enabled: bool,
 ) -> ModuleRule {
-    let transformer =
-        EcmascriptInputTransform::Plugin(Vc::cell(Box::new(NextServerActions { transform }) as _));
+    let transformer = EcmascriptInputTransform::Plugin(Vc::cell(Box::new(NextServerActions {
+        transform,
+        dynamic_io_enabled,
+    }) as _));
     ModuleRule::new(
         module_rule_match_js_no_url(enable_mdx_rs),
         vec![ModuleRuleEffect::ExtendEcmascriptTransforms {
@@ -33,6 +36,7 @@ pub fn get_server_actions_transform_rule(
 #[derive(Debug)]
 struct NextServerActions {
     transform: ActionsTransform,
+    dynamic_io_enabled: bool,
 }
 
 #[async_trait]
@@ -43,6 +47,7 @@ impl CustomTransformer for NextServerActions {
             &FileName::Real(ctx.file_path_str.into()),
             Config {
                 is_react_server_layer: matches!(self.transform, ActionsTransform::Server),
+                dynamic_io_enabled: self.dynamic_io_enabled,
                 hash_salt: "".into(),
             },
             ctx.comments.clone(),

diff --git a/crates/next-custom-transforms/src/transforms/server_actions.rs b/crates/next-custom-transforms/src/transforms/server_actions.rs
@@ -26,6 +26,7 @@ use swc_core::{
 #[serde(deny_unknown_fields, rename_all = "camelCase")]
 pub struct Config {
     pub is_react_server_layer: bool,
+    pub dynamic_io_enabled: bool,
     pub hash_salt: String,
 }
 
@@ -265,6 +266,7 @@ impl<C: Comments> ServerActions<C> {
                 &mut is_action_fn,
                 &mut cache_type,
                 &mut span,
+                self.config.dynamic_io_enabled,
             );
 
             if !self.config.is_react_server_layer {
@@ -1301,6 +1303,7 @@ impl<C: Comments> VisitMut for ServerActions<C> {
             &mut self.in_cache_file,
             &mut self.has_action,
             &mut self.has_cache,
+            self.config.dynamic_io_enabled,
         );
 
         // If we're in a "use cache" file, collect all original IDs from export
@@ -2355,6 +2358,7 @@ fn remove_server_directive_index_in_module(
     in_cache_file: &mut Option<String>,
     has_action: &mut bool,
     has_cache: &mut bool,
+    dynamic_io_enabled: bool,
 ) {
     let mut is_directive = true;
 
@@ -2383,6 +2387,21 @@ fn remove_server_directive_index_in_module(
                 // `use cache` or `use cache: foo`
                 if value == "use cache" || value.starts_with("use cache: ") {
                     if is_directive {
+                        if !dynamic_io_enabled {
+                            HANDLER.with(|handler| {
+                                handler
+                                    .struct_span_err(
+                                        *span,
+                                        format!(
+                                            "To use \"{value}\", please enable the experimental feature flag \"dynamicIO\" in your Next.js config.\n\n\
+                                            Read more: https://nextjs.org/docs/canary/app/api-reference/directives/use-cache#usage\n"
+                                        )
+                                        .as_str(),
+                                    )
+                                    .emit();
+                            })
+                        }
+
                         *in_cache_file = Some(if value == "use cache" {
                             "default".into()
                         } else {
@@ -2518,6 +2537,7 @@ fn remove_server_directive_index_in_fn(
     is_action_fn: &mut bool,
     cache_type: &mut Option<String>,
     action_span: &mut Option<Span>,
+    dynamic_io_enabled: bool,
 ) {
     let mut is_directive = true;
 
@@ -2560,6 +2580,21 @@ fn remove_server_directive_index_in_fn(
                 });
             } else if value == "use cache" || value.starts_with("use cache: ") {
                 if is_directive {
+                    if !dynamic_io_enabled {
+                        HANDLER.with(|handler| {
+                            handler
+                                .struct_span_err(
+                                    *span,
+                                    format!(
+                                        "To use \"{value}\", please enable the experimental feature flag \"dynamicIO\" in your Next.js config.\n\n\
+                                        Read more: https://nextjs.org/docs/canary/app/api-reference/directives/use-cache#usage\n"
+                                    )
+                                    .as_str(),
+                                )
+                                .emit();
+                        })
+                    }
+
                     *cache_type = Some(if value == "use cache" {
                         "default".into()
                     } else {

diff --git a/crates/next-custom-transforms/tests/errors.rs b/crates/next-custom-transforms/tests/errors.rs
@@ -176,7 +176,7 @@ fn react_server_actions_server_errors(input: PathBuf) {
                     FileName::Real(PathBuf::from("/app/item.js")).into(),
                     Config::WithOptions(Options {
                         is_react_server_layer: true,
-                        dynamic_io_enabled: false,
+                        dynamic_io_enabled: true,
                     }),
                     tr.comments.as_ref().clone(),
                     None,
@@ -185,6 +185,7 @@ fn react_server_actions_server_errors(input: PathBuf) {
                     &FileName::Real("/app/item.js".into()),
                     server_actions::Config {
                         is_react_server_layer: true,
+                        dynamic_io_enabled: true,
                         hash_salt: "".into(),
                     },
                     tr.comments.as_ref().clone(),
@@ -214,7 +215,7 @@ fn react_server_actions_client_errors(input: PathBuf) {
                     FileName::Real(PathBuf::from("/app/item.js")).into(),
                     Config::WithOptions(Options {
                         is_react_server_layer: false,
-                        dynamic_io_enabled: false,
+                        dynamic_io_enabled: true,
                     }),
                     tr.comments.as_ref().clone(),
                     None,
@@ -223,6 +224,7 @@ fn react_server_actions_client_errors(input: PathBuf) {
                     &FileName::Real("/app/item.js".into()),
                     server_actions::Config {
                         is_react_server_layer: false,
+                        dynamic_io_enabled: true,
                         hash_salt: "".into(),
                     },
                     tr.comments.as_ref().clone(),
@@ -256,3 +258,42 @@ fn next_transform_strip_page_exports_errors(input: PathBuf) {
         },
     );
 }
+
+#[fixture("tests/errors/use-cache-not-allowed/**/input.js")]
+fn use_cache_not_allowed(input: PathBuf) {
+    use next_custom_transforms::transforms::react_server_components::{Config, Options};
+    let output = input.parent().unwrap().join("output.js");
+    test_fixture(
+        syntax(),
+        &|tr| {
+            (
+                resolver(Mark::new(), Mark::new(), false),
+                server_components(
+                    FileName::Real(PathBuf::from("/app/item.js")).into(),
+                    Config::WithOptions(Options {
+                        is_react_server_layer: true,
+                        dynamic_io_enabled: false,
+                    }),
+                    tr.comments.as_ref().clone(),
+                    None,
+                ),
+                server_actions(
+                    &FileName::Real("/app/item.js".into()),
+                    server_actions::Config {
+                        is_react_server_layer: true,
+                        dynamic_io_enabled: false,
+                        hash_salt: "".into(),
+                    },
+                    tr.comments.as_ref().clone(),
+                ),
+            )
+        },
+        &input,
+        &output,
+        FixtureTestConfig {
+            allow_error: true,
+            module: Some(true),
+            ..Default::default()
+        },
+    );
+}
diff --git a/crates/next-custom-transforms/tests/errors/use-cache-not-allowed/1/input.js b/crates/next-custom-transforms/tests/errors/use-cache-not-allowed/1/input.js
@@ -0,0 +1,5 @@
+'use cache'
+
+export default async function Page() {
+  return <p>hello world</p>
+}
diff --git a/crates/next-custom-transforms/tests/errors/use-cache-not-allowed/1/output.js b/crates/next-custom-transforms/tests/errors/use-cache-not-allowed/1/output.js
@@ -0,0 +1,11 @@
+/* __next_internal_action_entry_do_not_use__ {"803128060c414d59f8552e4788b846c0d2b7f74743":"$$RSC_SERVER_CACHE_0"} */ import { registerServerReference } from "private-next-rsc-server-reference";
+import { encryptActionBoundArgs, decryptActionBoundArgs } from "private-next-rsc-action-encryption";
+import { cache as $$cache__ } from "private-next-rsc-cache-wrapper";
+export var $$RSC_SERVER_CACHE_0 = $$cache__("default", "803128060c414d59f8552e4788b846c0d2b7f74743", 0, async function Page() {
+    return <p>hello world</p>;
+});
+Object.defineProperty($$RSC_SERVER_CACHE_0, "name", {
+    "value": "Page",
+    "writable": false
+});
+export default registerServerReference($$RSC_SERVER_CACHE_0, "803128060c414d59f8552e4788b846c0d2b7f74743", null);
diff --git a/crates/next-custom-transforms/tests/errors/use-cache-not-allowed/1/output.stderr b/crates/next-custom-transforms/tests/errors/use-cache-not-allowed/1/output.stderr
@@ -0,0 +1,8 @@
+  x To use "use cache", please enable the experimental feature flag "dynamicIO" in your Next.js config.
+  | 
+  | Read more: https://nextjs.org/docs/canary/app/api-reference/directives/use-cache#usage
+  | 
+   ,-[input.js:1:1]
+ 1 | 'use cache'
+   : ^^^^^^^^^^^
+   `----
diff --git a/crates/next-custom-transforms/tests/errors/use-cache-not-allowed/2/input.js b/crates/next-custom-transforms/tests/errors/use-cache-not-allowed/2/input.js
@@ -0,0 +1,5 @@
+export default async function Page() {
+  'use cache: x'
+
+  return <p>hello world</p>
+}
diff --git a/crates/next-custom-transforms/tests/errors/use-cache-not-allowed/2/output.js b/crates/next-custom-transforms/tests/errors/use-cache-not-allowed/2/output.js
@@ -0,0 +1,11 @@
+/* __next_internal_action_entry_do_not_use__ {"803128060c414d59f8552e4788b846c0d2b7f74743":"$$RSC_SERVER_CACHE_0"} */ import { registerServerReference } from "private-next-rsc-server-reference";
+import { encryptActionBoundArgs, decryptActionBoundArgs } from "private-next-rsc-action-encryption";
+import { cache as $$cache__ } from "private-next-rsc-cache-wrapper";
+export var $$RSC_SERVER_CACHE_0 = $$cache__("x", "803128060c414d59f8552e4788b846c0d2b7f74743", 0, async function Page() {
+    return <p>hello world</p>;
+});
+Object.defineProperty($$RSC_SERVER_CACHE_0, "name", {
+    "value": "Page",
+    "writable": false
+});
+export default registerServerReference($$RSC_SERVER_CACHE_0, "803128060c414d59f8552e4788b846c0d2b7f74743", null);
diff --git a/crates/next-custom-transforms/tests/errors/use-cache-not-allowed/2/output.stderr b/crates/next-custom-transforms/tests/errors/use-cache-not-allowed/2/output.stderr
@@ -0,0 +1,9 @@
+  x To use "use cache: x", please enable the experimental feature flag "dynamicIO" in your Next.js config.
+  | 
+  | Read more: https://nextjs.org/docs/canary/app/api-reference/directives/use-cache#usage
+  | 
+   ,-[input.js:2:1]
+ 1 | export default async function Page() {
+ 2 |   'use cache: x'
+   :   ^^^^^^^^^^^^^^
+   `----
diff --git a/crates/next-custom-transforms/tests/fixture.rs b/crates/next-custom-transforms/tests/fixture.rs
@@ -414,6 +414,7 @@ fn server_actions_server_fixture(input: PathBuf) {
                     &FileName::Real("/app/item.js".into()),
                     server_actions::Config {
                         is_react_server_layer: true,
+                        dynamic_io_enabled: true,
                         hash_salt: "".into(),
                     },
                     _tr.comments.as_ref().clone(),
@@ -445,6 +446,7 @@ fn next_font_with_directive_fixture(input: PathBuf) {
                     &FileName::Real("/app/test.tsx".into()),
                     server_actions::Config {
                         is_react_server_layer: true,
+                        dynamic_io_enabled: true,
                         hash_salt: "".into(),
                     },
                     _tr.comments.as_ref().clone(),
@@ -469,6 +471,7 @@ fn server_actions_client_fixture(input: PathBuf) {
                     &FileName::Real("/app/item.js".into()),
                     server_actions::Config {
                         is_react_server_layer: false,
+                        dynamic_io_enabled: true,
                         hash_salt: "".into(),
                     },
                     _tr.comments.as_ref().clone(),

diff --git a/packages/next/src/build/swc/options.ts b/packages/next/src/build/swc/options.ts
@@ -209,6 +209,7 @@ function getBaseSWCOptions({
       isAppRouterPagesLayer && !jest
         ? {
             isReactServerLayer,
+            dynamicIoEnabled: isDynamicIo,
             hashSalt: serverReferenceHashSalt,
           }
         : undefined,

diff --git a/packages/next/src/server/use-cache/use-cache-wrapper.ts b/packages/next/src/server/use-cache/use-cache-wrapper.ts
@@ -441,11 +441,6 @@ export function cache(
   boundArgsLength: number,
   fn: any
 ) {
-  if (!process.env.__NEXT_DYNAMIC_IO) {
-    throw new Error(
-      '"use cache" is only available with the experimental.dynamicIO config.'
-    )
-  }
   for (const [key, value] of Object.entries(
     _globalThis.__nextCacheHandlers || {}
   )) {

diff --git a/test/e2e/app-dir/use-cache-without-dynamic-io/app/layout.tsx b/test/e2e/app-dir/use-cache-without-dynamic-io/app/layout.tsx
@@ -0,0 +1,8 @@
+import { ReactNode } from 'react'
+export default function Root({ children }: { children: ReactNode }) {
+  return (
+    <html>
+      <body>{children}</body>
+    </html>
+  )
+}
diff --git a/test/e2e/app-dir/use-cache-without-dynamic-io/app/page.tsx b/test/e2e/app-dir/use-cache-without-dynamic-io/app/page.tsx
@@ -0,0 +1,5 @@
+'use cache'
+
+export default async function Page() {
+  return <p>hello world</p>
+}
diff --git a/test/e2e/app-dir/use-cache-without-dynamic-io/next.config.js b/test/e2e/app-dir/use-cache-without-dynamic-io/next.config.js
@@ -0,0 +1,6 @@
+/**
+ * @type {import('next').NextConfig}
+ */
+const nextConfig = {}
+
+module.exports = nextConfig