Turbopack: Ensure server actions sourcemaps tests pass (#76157)

## What?

Follow-up to #76129. Fixes the sourcemap, ensures the mappings are not
carried over when compiling for the client. For the server these
mappings are preserved.

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Author: timneutkens

crates/next-core/src/next_client/transforms.rs

@@ -73,13 +73,17 @@ pub async fn get_next_client_transforms_rules(
         }
         ClientContextType::App { .. } => {
             is_app_dir = true;
-            rules.push(get_server_actions_transform_rule(
-                ActionsTransform::Client,
-                encryption_key,
-                enable_mdx_rs,
-                use_cache_enabled,
-                cache_kinds,
-            ));
+            rules.push(
+                get_server_actions_transform_rule(
+                    mode,
+                    ActionsTransform::Client,
+                    encryption_key,
+                    enable_mdx_rs,
+                    use_cache_enabled,
+                    cache_kinds,
+                )
+                .await?,
+            );
         }
         ClientContextType::Fallback | ClientContextType::Other => {}
     };

crates/next-core/src/next_server/transforms.rs

@@ -111,39 +111,51 @@ pub async fn get_next_server_transforms_rules(
         ServerContextType::AppSSR { .. } => {
             // Yah, this is SSR, but this is still treated as a Client transform layer.
             // need to apply to foreign code too
-            rules.push(get_server_actions_transform_rule(
-                ActionsTransform::Client,
-                encryption_key,
-                mdx_rs,
-                use_cache_enabled,
-                cache_kinds,
-            ));
+            rules.push(
+                get_server_actions_transform_rule(
+                    mode,
+                    ActionsTransform::Client,
+                    encryption_key,
+                    mdx_rs,
+                    use_cache_enabled,
+                    cache_kinds,
+                )
+                .await?,
+            );
 
             is_app_dir = true;
 
             false
         }
         ServerContextType::AppRSC { .. } => {
-            rules.push(get_server_actions_transform_rule(
-                ActionsTransform::Server,
-                encryption_key,
-                mdx_rs,
-                use_cache_enabled,
-                cache_kinds,
-            ));
+            rules.push(
+                get_server_actions_transform_rule(
+                    mode,
+                    ActionsTransform::Server,
+                    encryption_key,
+                    mdx_rs,
+                    use_cache_enabled,
+                    cache_kinds,
+                )
+                .await?,
+            );
 
             is_app_dir = true;
 
             true
         }
         ServerContextType::AppRoute { .. } => {
-            rules.push(get_server_actions_transform_rule(
-                ActionsTransform::Server,
-                encryption_key,
-                mdx_rs,
-                use_cache_enabled,
-                cache_kinds,
-            ));
+            rules.push(
+                get_server_actions_transform_rule(
+                    mode,
+                    ActionsTransform::Server,
+                    encryption_key,
+                    mdx_rs,
+                    use_cache_enabled,
+                    cache_kinds,
+                )
+                .await?,
+            );
 
             is_app_dir = true;
 

crates/next-core/src/next_shared/transforms/server_actions.rs

@@ -3,12 +3,12 @@ use async_trait::async_trait;
 use next_custom_transforms::transforms::server_actions::{server_actions, Config};
 use swc_core::{common::FileName, ecma::ast::Program};
 use turbo_rcstr::RcStr;
-use turbo_tasks::ResolvedVc;
+use turbo_tasks::{ResolvedVc, Vc};
 use turbopack::module_options::{ModuleRule, ModuleRuleEffect};
 use turbopack_ecmascript::{CustomTransformer, EcmascriptInputTransform, TransformContext};
 
 use super::module_rule_match_js_no_url;
-use crate::next_config::CacheKinds;
+use crate::{mode::NextMode, next_config::CacheKinds};
 
 #[derive(Debug)]
 pub enum ActionsTransform {
@@ -17,27 +17,29 @@ pub enum ActionsTransform {
 }
 
 /// Returns a rule which applies the Next.js Server Actions transform.
-pub fn get_server_actions_transform_rule(
+pub async fn get_server_actions_transform_rule(
+    mode: Vc<NextMode>,
     transform: ActionsTransform,
     encryption_key: ResolvedVc<RcStr>,
     enable_mdx_rs: bool,
     use_cache_enabled: bool,
     cache_kinds: ResolvedVc<CacheKinds>,
-) -> ModuleRule {
+) -> Result<ModuleRule> {
     let transformer =
         EcmascriptInputTransform::Plugin(ResolvedVc::cell(Box::new(NextServerActions {
+            mode: *mode.await?,
             transform,
             encryption_key,
             use_cache_enabled,
             cache_kinds,
         }) as _));
-    ModuleRule::new(
+    Ok(ModuleRule::new(
         module_rule_match_js_no_url(enable_mdx_rs),
         vec![ModuleRuleEffect::ExtendEcmascriptTransforms {
             prepend: ResolvedVc::cell(vec![]),
             append: ResolvedVc::cell(vec![transformer]),
         }],
-    )
+    ))
 }
 
 #[derive(Debug)]
@@ -46,6 +48,7 @@ struct NextServerActions {
     encryption_key: ResolvedVc<RcStr>,
     use_cache_enabled: bool,
     cache_kinds: ResolvedVc<CacheKinds>,
+    mode: NextMode,
 }
 
 #[async_trait]
@@ -56,6 +59,7 @@ impl CustomTransformer for NextServerActions {
             &FileName::Real(ctx.file_path_str.into()),
             Config {
                 is_react_server_layer: matches!(self.transform, ActionsTransform::Server),
+                is_development: self.mode.is_development(),
                 use_cache_enabled: self.use_cache_enabled,
                 hash_salt: self.encryption_key.await?.to_string(),
                 cache_kinds: self.cache_kinds.owned().await?,

crates/next-custom-transforms/src/transforms/server_actions.rs

@@ -16,6 +16,7 @@ use swc_core::{
     common::{
         comments::{Comment, CommentKind, Comments},
         errors::HANDLER,
+        source_map::PURE_SP,
         util::take::Take,
         BytePos, FileName, Mark, Span, SyntaxContext, DUMMY_SP,
     },
@@ -32,6 +33,7 @@ use turbo_rcstr::RcStr;
 #[serde(deny_unknown_fields, rename_all = "camelCase")]
 pub struct Config {
     pub is_react_server_layer: bool,
+    pub is_development: bool,
     pub use_cache_enabled: bool,
     pub hash_salt: String,
     pub cache_kinds: FxHashSet<RcStr>,
@@ -1859,7 +1861,17 @@ impl<C: Comments> VisitMut for ServerActions<C> {
                             ExportDefaultExpr {
                                 span: DUMMY_SP,
                                 expr: Box::new(Expr::Call(CallExpr {
-                                    span: ident.span,
+                                    // In development we generate these spans for sourcemapping with
+                                    // better logs/errors
+                                    // For production this is not generated because it would leak
+                                    // server code when available from the browser.
+                                    span: if self.config.is_react_server_layer
+                                        || self.config.is_development
+                                    {
+                                        ident.span
+                                    } else {
+                                        PURE_SP
+                                    },
                                     callee: Callee::Expr(Box::new(Expr::Ident(
                                         create_ref_ident.clone(),
                                     ))),
@@ -1876,8 +1888,8 @@ impl<C: Comments> VisitMut for ServerActions<C> {
                         ));
                         new.push(export_expr);
                     } else {
-                        let call_expr_span = Span::dummy_with_cmt();
-                        self.comments.add_pure_comment(call_expr_span.lo);
+                        let dummy_pure_span = Span::dummy_with_cmt();
+                        self.comments.add_pure_comment(dummy_pure_span.lo);
 
                         let export_expr =
                             ModuleItem::ModuleDecl(ModuleDecl::ExportDecl(ExportDecl {
@@ -1888,10 +1900,25 @@ impl<C: Comments> VisitMut for ServerActions<C> {
                                     decls: vec![VarDeclarator {
                                         span: DUMMY_SP,
                                         name: Pat::Ident(
-                                            IdentName::new(export_name.clone(), ident.span).into(),
+                                            IdentName::new(
+                                                export_name.clone(),
+                                                // In development we generate these spans for
+                                                // sourcemapping with better logs/errors
+                                                // For production this is not generated because it
+                                                // would leak server code when available from the
+                                                // browser.
+                                                if self.config.is_react_server_layer
+                                                    || self.config.is_development
+                                                {
+                                                    ident.span
+                                                } else {
+                                                    DUMMY_SP
+                                                },
+                                            )
+                                            .into(),
                                         ),
                                         init: Some(Box::new(Expr::Call(CallExpr {
-                                            span: call_expr_span,
+                                            span: dummy_pure_span,
                                             callee: Callee::Expr(Box::new(Expr::Ident(
                                                 create_ref_ident.clone(),
                                             ))),

crates/next-custom-transforms/tests/errors.rs

@@ -165,6 +165,7 @@ fn react_server_actions_errors(input: PathBuf) {
                     &FileName::Real("/app/item.js".into()),
                     server_actions::Config {
                         is_react_server_layer,
+                        is_development: true,
                         use_cache_enabled: true,
                         hash_salt: "".into(),
                         cache_kinds: FxHashSet::default(),
@@ -225,6 +226,7 @@ fn use_cache_not_allowed(input: PathBuf) {
                     &FileName::Real("/app/item.js".into()),
                     server_actions::Config {
                         is_react_server_layer: true,
+                        is_development: true,
                         use_cache_enabled: false,
                         hash_salt: "".into(),
                         cache_kinds: FxHashSet::from_iter(["x".into()]),

crates/next-custom-transforms/tests/fixture.rs

@@ -541,6 +541,7 @@ fn next_font_loaders_fixture(input: PathBuf) {
 fn server_actions_fixture(input: PathBuf) {
     let output = input.parent().unwrap().join("output.js");
     let is_react_server_layer = input.iter().any(|s| s.to_str() == Some("server-graph"));
+    let is_development = input.iter().any(|s| s.to_str() == Some("development"));
     test_fixture(
         syntax(),
         &|_tr| {
@@ -550,6 +551,7 @@ fn server_actions_fixture(input: PathBuf) {
                     &FileName::Real("/app/item.js".into()),
                     server_actions::Config {
                         is_react_server_layer,
+                        is_development,
                         use_cache_enabled: true,
                         hash_salt: "".into(),
                         cache_kinds: FxHashSet::from_iter(["x".into()]),
@@ -584,6 +586,7 @@ fn next_font_with_directive_fixture(input: PathBuf) {
                     &FileName::Real("/app/test.tsx".into()),
                     server_actions::Config {
                         is_react_server_layer: true,
+                        is_development: true,
                         use_cache_enabled: true,
                         hash_salt: "".into(),
                         cache_kinds: FxHashSet::default(),
@@ -875,7 +878,10 @@ fn test_edge_assert(input: PathBuf) {
 
 #[fixture("tests/fixture/source-maps/**/input.js")]
 fn test_source_maps(input: PathBuf) {
-    let output = input.parent().unwrap().join("output.js");
+    let output: PathBuf = input.parent().unwrap().join("output.js");
+    let is_react_server_layer = input.iter().any(|s| s.to_str() == Some("server-graph"));
+    let is_development = input.iter().any(|s| s.to_str() == Some("development"));
+
     test_fixture(
         syntax(),
         &|_tr| {
@@ -884,7 +890,8 @@ fn test_source_maps(input: PathBuf) {
                 server_actions(
                     &FileName::Real("/app/item.js".into()),
                     server_actions::Config {
-                        is_react_server_layer: true,
+                        is_react_server_layer,
+                        is_development,
                         use_cache_enabled: true,
                         hash_salt: "".into(),
                         cache_kinds: FxHashSet::from_iter([]),

crates/next-custom-transforms/tests/fixture/source-maps/client-graph/development/server-actions/1/input.js

@@ -0,0 +1,38 @@
+'use server'
+
+import 'server-only'
+
+import { redirect } from 'next/navigation'
+import { headers, cookies } from 'next/headers'
+
+export async function getHeaders() {
+  console.log('accept header:', (await headers()).get('accept'))
+  ;(await cookies()).set('test-cookie', Date.now())
+}
+
+export async function inc(value) {
+  return value + 1
+}
+
+export async function slowInc(value) {
+  await new Promise((resolve) => setTimeout(resolve, 10000))
+  return value + 1
+}
+
+export async function dec(value) {
+  return value - 1
+}
+
+export default async function (value) {
+  console.log('this_is_sensitive_info')
+  return value * 2
+}
+
+export async function redirectAction(path) {
+  redirect(path)
+}
+
+const original = async () => {
+  console.log('action')
+}
+export { original as renamed }

crates/next-custom-transforms/tests/fixture/source-maps/client-graph/development/server-actions/1/output.map

@@ -0,0 +1,38 @@
+'use server'
+
+import 'server-only'
+
+import { redirect } from 'next/navigation'
+import { headers, cookies } from 'next/headers'
+
+export async function getHeaders() {
+  console.log('accept header:', (await headers()).get('accept'))
+  ;(await cookies()).set('test-cookie', Date.now())
+}
+
+export async function inc(value) {
+  return value + 1
+}
+
+export async function slowInc(value) {
+  await new Promise((resolve) => setTimeout(resolve, 10000))
+  return value + 1
+}
+
+export async function dec(value) {
+  return value - 1
+}
+
+export default async function (value) {
+  console.log('this_is_sensitive_info')
+  return value * 2
+}
+
+export async function redirectAction(path) {
+  redirect(path)
+}
+
+const original = async () => {
+  console.log('action')
+}
+export { original as renamed }