Turbopack build: Implement app/global-error.tsx (#67803)

Implements global-error.tsx for Turbopack, this feature was missing.

While adding this @sokra and I found that the
server_component_transition was incorrectly wrapping a module around the
server component, this is now refactored to re-export the server
component instead, making the transition behave as expected.

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packages/next-swc/crates/napi/src/app_structure.rs

@@ -153,6 +153,7 @@ async fn prepare_components_for_js(
         page,
         layout,
         error,
+        global_error: _,
         loading,
         template,
         not_found,

packages/next-swc/crates/next-core/src/app_structure.rs

@@ -44,6 +44,8 @@ pub struct Components {
     #[serde(skip_serializing_if = "Option::is_none")]
     pub error: Option<Vc<FileSystemPath>>,
     #[serde(skip_serializing_if = "Option::is_none")]
+    pub global_error: Option<Vc<FileSystemPath>>,
+    #[serde(skip_serializing_if = "Option::is_none")]
     pub loading: Option<Vc<FileSystemPath>>,
     #[serde(skip_serializing_if = "Option::is_none")]
     pub template: Option<Vc<FileSystemPath>>,
@@ -63,6 +65,7 @@ impl Components {
             page: None,
             layout: self.layout,
             error: self.error,
+            global_error: self.global_error,
             loading: self.loading,
             template: self.template,
             not_found: self.not_found,
@@ -333,6 +336,7 @@ async fn get_directory_tree_internal(
                             "page" => components.page = Some(file),
                             "layout" => components.layout = Some(file),
                             "error" => components.error = Some(file),
+                            "global-error" => components.global_error = Some(file),
                             "loading" => components.loading = Some(file),
                             "template" => components.template = Some(file),
                             "not-found" => components.not_found = Some(file),

packages/next-swc/crates/next-core/src/loader_tree.rs

@@ -107,14 +107,8 @@ impl LoaderTreeBuilder {
             let i = self.unique_number();
             let identifier = magic_identifier::mangle(&format!("{name} #{i}"));
 
-            let source = Vc::upcast(FileSource::new(component));
-            let reference_ty = Value::new(ReferenceType::EcmaScriptModules(
-                EcmaScriptModulesReferenceSubType::Undefined,
-            ));
-            let module = self
-                .server_component_transition
-                .process(source, self.context, reference_ty)
-                .module();
+            let module =
+                process_module(&self.context, &self.server_component_transition, component);
 
             writeln!(
                 self.loader_tree_code,
@@ -126,7 +120,7 @@ impl LoaderTreeBuilder {
             self.imports.push(
                 formatdoc!(
                     r#"
-                    import {} from "COMPONENT_{}";
+                    import * as {} from "COMPONENT_{}";
                     "#,
                     identifier,
                     i
@@ -381,6 +375,7 @@ impl LoaderTreeBuilder {
             page,
             default,
             error,
+            global_error: _,
             layout,
             loading,
             template,
@@ -426,6 +421,16 @@ impl LoaderTreeBuilder {
     }
 
     async fn build(mut self, loader_tree: Vc<LoaderTree>) -> Result<LoaderTreeModule> {
+        let components = loader_tree.await?.components.await?;
+        if let Some(global_error) = components.global_error {
+            let module = process_module(
+                &self.context,
+                &self.server_component_transition,
+                global_error,
+            );
+            self.inner_assets.insert(GLOBAL_ERROR.into(), module);
+        };
+
         self.walk_tree(loader_tree, true).await?;
         Ok(LoaderTreeModule {
             imports: self.imports,
@@ -455,3 +460,20 @@ impl LoaderTreeModule {
             .await
     }
 }
+
+pub const GLOBAL_ERROR: &str = "GLOBAL_ERROR_MODULE";
+
+fn process_module(
+    &context: &Vc<ModuleAssetContext>,
+    &server_component_transition: &Vc<Box<dyn Transition>>,
+    component: Vc<FileSystemPath>,
+) -> Vc<Box<dyn Module>> {
+    let source = Vc::upcast(FileSource::new(component));
+    let reference_ty = Value::new(ReferenceType::EcmaScriptModules(
+        EcmaScriptModulesReferenceSubType::Undefined,
+    ));
+
+    server_component_transition
+        .process(source, context, reference_ty)
+        .module()
+}

packages/next-swc/crates/next-core/src/next_app/app_page_entry.rs

@@ -22,7 +22,7 @@ use turbopack_binding::{
 use super::app_entry::AppEntry;
 use crate::{
     app_structure::LoaderTree,
-    loader_tree::LoaderTreeModule,
+    loader_tree::{LoaderTreeModule, GLOBAL_ERROR},
     next_app::{AppPage, AppPath},
     next_config::NextConfig,
     next_edge::entry::wrap_edge_entry,
@@ -81,8 +81,11 @@ pub async fn get_app_page_entry(
         indexmap! {
             "VAR_DEFINITION_PAGE" => page.to_string().into(),
             "VAR_DEFINITION_PATHNAME" => pathname.clone(),
-            // TODO(alexkirsz) Support custom global error.
-            "VAR_MODULE_GLOBAL_ERROR" => "next/dist/client/components/error-boundary".into(),
+            "VAR_MODULE_GLOBAL_ERROR" => if inner_assets.contains_key(GLOBAL_ERROR) {
+                GLOBAL_ERROR.into()
+             } else {
+                "next/dist/client/components/error-boundary".into()
+            },
         },
         indexmap! {
             "tree" => loader_tree_code,

packages/next-swc/crates/next-core/src/next_server_component/server_component_module.rs

@@ -1,5 +1,3 @@
-use std::collections::BTreeMap;
-
 use anyhow::{bail, Result};
 use indoc::formatdoc;
 use turbo_tasks::{RcStr, Vc};
@@ -12,10 +10,7 @@ use turbopack_binding::turbopack::{
         module::Module,
         reference::ModuleReferences,
     },
-    ecmascript::{
-        chunk::EcmascriptChunkType,
-        references::esm::{EsmExport, EsmExports},
-    },
+    ecmascript::{chunk::EcmascriptChunkType, references::esm::EsmExports},
     turbopack::ecmascript::{
         chunk::{
             EcmascriptChunkItem, EcmascriptChunkItemContent, EcmascriptChunkPlaceable,
@@ -95,17 +90,14 @@ impl ChunkableModule for NextServerComponentModule {
 impl EcmascriptChunkPlaceable for NextServerComponentModule {
     #[turbo_tasks::function]
     fn get_exports(&self) -> Vc<EcmascriptExports> {
-        let exports = BTreeMap::from([(
-            "default".into(),
-            EsmExport::ImportedNamespace(Vc::upcast(NextServerComponentModuleReference::new(
-                Vc::upcast(self.module),
-            ))),
-        )]);
+        let module_reference = Vc::upcast(NextServerComponentModuleReference::new(Vc::upcast(
+            self.module,
+        )));
 
         EcmascriptExports::EsmExports(
             EsmExports {
-                exports,
-                star_exports: Default::default(),
+                exports: Default::default(),
+                star_exports: vec![module_reference],
             }
             .cell(),
         )
@@ -139,9 +131,7 @@ impl EcmascriptChunkItem for BuildServerComponentChunkItem {
         Ok(EcmascriptChunkItemContent {
             inner_code: formatdoc!(
                 r#"
-                    __turbopack_esm__({{
-                        default: () => __turbopack_import__({}),
-                    }});
+                    __turbopack_export_namespace__(__turbopack_import__({}));
                 "#,
                 StringifyJs(&module_id),
             )

test/turbopack-build-tests-manifest.json

@@ -1648,36 +1648,34 @@
     },
     "test/e2e/app-dir/global-error/basic/index.test.ts": {
       "passed": [
-        "app dir - global error should catch metadata error in error boundary if presented"
-      ],
-      "failed": [
+        "app dir - global error should catch metadata error in error boundary if presented",
         "app dir - global error should catch metadata error in global-error if no error boundary is presented",
         "app dir - global error should catch the client error thrown in the nested routes",
         "app dir - global error should render global error for error in client components",
         "app dir - global error should render global error for error in server components",
         "app dir - global error should trigger error component when an error happens during rendering"
       ],
+      "failed": [],
       "pending": [],
       "flakey": [],
       "runtimeError": false
     },
     "test/e2e/app-dir/global-error/catch-all/index.test.ts": {
       "passed": [
         "app dir - global error - with catch-all route should render 404 page correctly",
-        "app dir - global error - with catch-all route should render catch-all route correctly"
-      ],
-      "failed": [
+        "app dir - global error - with catch-all route should render catch-all route correctly",
         "app dir - global error - with catch-all route should render global error correctly"
       ],
+      "failed": [],
       "pending": [],
       "flakey": [],
       "runtimeError": false
     },
     "test/e2e/app-dir/global-error/layout-error/index.test.ts": {
-      "passed": [],
-      "failed": [
+      "passed": [
         "app dir - global error - layout error should render global error for error in server components"
       ],
+      "failed": [],
       "pending": [],
       "flakey": [],
       "runtimeError": false