fix externals in side-effect optimized modules (vercel/turborepo#7797)

### Description

fixes a problem where an async module wrapper is generated for external
modules in a "locals" module part when there is usage of the external
module in the locals part

fixes #63485

### Testing Instructions

<!--
  Give a quick description of steps to test your changes.
-->


Closes PACK-2810

fixes PACK-2805

crates/turbopack-ecmascript/src/lib.rs

@@ -515,6 +515,7 @@ impl EcmascriptModuleAsset {
             chunking_context,
             analyze.references,
             analyze.code_generation,
+            analyze.async_module,
             analyze.source_map,
             analyze.exports,
             async_module_info,
@@ -660,7 +661,7 @@ impl ChunkItem for ModuleChunkItem {
     #[turbo_tasks::function]
     async fn is_self_async(&self) -> Result<Vc<bool>> {
         if let Some(async_module) = *self.module.get_async_module().await? {
-            Ok(async_module.is_self_async())
+            Ok(async_module.is_self_async(self.module.failsafe_analyze().await?.references))
         } else {
             Ok(Vc::cell(false))
         }
@@ -727,6 +728,7 @@ impl EcmascriptModuleContent {
         chunking_context: Vc<Box<dyn EcmascriptChunkingContext>>,
         references: Vc<ModuleReferences>,
         code_generation: Vc<CodeGenerateables>,
+        async_module: Vc<OptionAsyncModule>,
         source_map: Vc<OptionSourceMap>,
         exports: Vc<EcmascriptExports>,
         async_module_info: Option<Vc<AsyncModuleInfo>>,
@@ -744,6 +746,13 @@ impl EcmascriptModuleContent {
                 code_gens.push(code_gen.code_generation(chunking_context));
             }
         }
+        if let Some(async_module) = *async_module.await? {
+            code_gens.push(async_module.code_generation(
+                chunking_context,
+                async_module_info,
+                references,
+            ));
+        }
         for c in code_generation.await?.iter() {
             match c {
                 CodeGen::CodeGenerateable(c) => {

crates/turbopack-ecmascript/src/references/async_module.rs

@@ -6,17 +6,17 @@ use swc_core::{
     ecma::ast::{ArrayLit, ArrayPat, Expr, Ident, Program},
     quote,
 };
-use turbo_tasks::{trace::TraceRawVcs, TryFlatJoinIterExt, TryJoinIterExt, Vc};
+use turbo_tasks::{trace::TraceRawVcs, ReadRef, TryFlatJoinIterExt, TryJoinIterExt, Vc};
 use turbopack_core::{
-    chunk::{AsyncModuleInfo, ChunkableModule},
+    chunk::{AsyncModuleInfo, ChunkableModule, ChunkableModuleReference, ChunkingType},
     reference::{ModuleReference, ModuleReferences},
     resolve::ExternalType,
 };
 
 use super::esm::base::ReferencedAsset;
 use crate::{
     chunk::{EcmascriptChunkPlaceable, EcmascriptChunkingContext},
-    code_gen::{CodeGenerateableWithAsyncModuleInfo, CodeGeneration},
+    code_gen::CodeGeneration,
     create_visitor,
     references::esm::base::insert_hoisted_stmt,
 };
@@ -48,7 +48,6 @@ impl OptionAsyncModuleOptions {
 #[turbo_tasks::value(shared)]
 pub struct AsyncModule {
     pub placeable: Vc<Box<dyn EcmascriptChunkPlaceable>>,
-    pub references: Vc<ModuleReferences>,
     pub has_top_level_await: bool,
     pub import_externals: bool,
 }
@@ -81,23 +80,41 @@ impl OptionAsyncModule {
 #[turbo_tasks::value(transparent)]
 struct AsyncModuleIdents(IndexSet<String>);
 
+async fn get_inherit_async_referenced_asset(
+    r: Vc<Box<dyn ModuleReference>>,
+) -> Result<Option<ReadRef<ReferencedAsset>>> {
+    let Some(r) = Vc::try_resolve_downcast::<Box<dyn ChunkableModuleReference>>(r).await? else {
+        return Ok(None);
+    };
+    let Some(ty) = *r.chunking_type().await? else {
+        return Ok(None);
+    };
+    if !matches!(ty, ChunkingType::ParallelInheritAsync) {
+        return Ok(None);
+    };
+    let referenced_asset: turbo_tasks::ReadRef<ReferencedAsset> =
+        ReferencedAsset::from_resolve_result(r.resolve_reference()).await?;
+    Ok(Some(referenced_asset))
+}
+
 #[turbo_tasks::value_impl]
 impl AsyncModule {
     #[turbo_tasks::function]
     async fn get_async_idents(
         &self,
         chunking_context: Vc<Box<dyn EcmascriptChunkingContext>>,
         async_module_info: Vc<AsyncModuleInfo>,
+        references: Vc<ModuleReferences>,
     ) -> Result<Vc<AsyncModuleIdents>> {
         let async_module_info = async_module_info.await?;
 
-        let reference_idents = self
-            .references
+        let reference_idents = references
             .await?
             .iter()
             .map(|r| async {
-                let referenced_asset =
-                    ReferencedAsset::from_resolve_result(r.resolve_reference()).await?;
+                let Some(referenced_asset) = get_inherit_async_referenced_asset(*r).await? else {
+                    return Ok(None);
+                };
                 Ok(match &*referenced_asset {
                     ReferencedAsset::External(
                         _,
@@ -134,20 +151,21 @@ impl AsyncModule {
     }
 
     #[turbo_tasks::function]
-    pub(crate) async fn is_self_async(&self) -> Result<Vc<bool>> {
+    pub(crate) async fn is_self_async(&self, references: Vc<ModuleReferences>) -> Result<Vc<bool>> {
         if self.has_top_level_await {
             return Ok(Vc::cell(true));
         }
 
         Ok(Vc::cell(
             self.import_externals
-                && self
-                    .references
+                && references
                     .await?
                     .iter()
                     .map(|r| async {
-                        let referenced_asset =
-                            ReferencedAsset::from_resolve_result(r.resolve_reference()).await?;
+                        let Some(referenced_asset) = get_inherit_async_referenced_asset(*r).await?
+                        else {
+                            return Ok(false);
+                        };
                         Ok(matches!(
                             &*referenced_asset,
                             ReferencedAsset::External(
@@ -177,21 +195,19 @@ impl AsyncModule {
             has_top_level_await: self.await?.has_top_level_await,
         })))
     }
-}
 
-#[turbo_tasks::value_impl]
-impl CodeGenerateableWithAsyncModuleInfo for AsyncModule {
     #[turbo_tasks::function]
-    async fn code_generation(
+    pub async fn code_generation(
         self: Vc<Self>,
         chunking_context: Vc<Box<dyn EcmascriptChunkingContext>>,
         async_module_info: Option<Vc<AsyncModuleInfo>>,
+        references: Vc<ModuleReferences>,
     ) -> Result<Vc<CodeGeneration>> {
         let mut visitors = Vec::new();
 
         if let Some(async_module_info) = async_module_info {
             let async_idents = self
-                .get_async_idents(chunking_context, async_module_info)
+                .get_async_idents(chunking_context, async_module_info, references)
                 .await?;
 
             if !async_idents.is_empty() {

crates/turbopack-ecmascript/src/references/mod.rs

@@ -575,7 +575,7 @@ pub(crate) async fn analyse_ecmascript_module_internal(
         *r = r.resolve().await?;
     }
     for r in import_references.iter() {
-        // `add_reference` will avoid adding duplicate references
+        // `add_import_reference` will avoid adding duplicate references
         analysis.add_import_reference(*r);
     }
     for i in evaluation_references {
@@ -750,13 +750,11 @@ pub(crate) async fn analyse_ecmascript_module_internal(
     if eval_context.is_esm() || specified_type == SpecifiedModuleType::EcmaScript {
         let async_module = AsyncModule {
             placeable: Vc::upcast(module),
-            references: Vc::cell(import_references.iter().map(|&r| Vc::upcast(r)).collect()),
             has_top_level_await,
             import_externals,
         }
         .cell();
         analysis.set_async_module(async_module);
-        analysis.add_code_gen_with_availability_info(async_module);
     } else if let Some(span) = top_level_await_span {
         AnalyzeIssue {
             code: None,

crates/turbopack-ecmascript/src/side_effect_optimization/facade/chunk_item.rs

@@ -68,9 +68,10 @@ impl EcmascriptChunkItem for EcmascriptModuleFacadeChunkItem {
 
         let mut code = RopeBuilder::default();
 
-        let references = self.module.references().await?;
-        let mut code_gens = Vec::with_capacity(references.len() + 2);
-        for r in references.iter() {
+        let references = self.module.references();
+        let references_ref = references.await?;
+        let mut code_gens = Vec::with_capacity(references_ref.len() + 2);
+        for r in references_ref.iter() {
             let r = r.resolve().await?;
             if let Some(code_gen) =
                 Vc::try_resolve_sidecast::<Box<dyn CodeGenerateableWithAsyncModuleInfo>>(r).await?
@@ -82,12 +83,11 @@ impl EcmascriptChunkItem for EcmascriptModuleFacadeChunkItem {
                 code_gens.push(code_gen.code_generation(chunking_context));
             }
         }
-
-        code_gens.push(
-            self.module
-                .async_module()
-                .code_generation(chunking_context, async_module_info),
-        );
+        code_gens.push(self.module.async_module().code_generation(
+            chunking_context,
+            async_module_info,
+            references,
+        ));
         code_gens.push(exports.code_generation(chunking_context));
         let code_gens = code_gens.into_iter().try_join().await?;
         let code_gens = code_gens.iter().map(|cg| &**cg).collect::<Vec<_>>();
@@ -183,4 +183,18 @@ impl ChunkItem for EcmascriptModuleFacadeChunkItem {
     fn module(&self) -> Vc<Box<dyn Module>> {
         Vc::upcast(self.module)
     }
+
+    #[turbo_tasks::function]
+    async fn is_self_async(&self) -> Result<Vc<bool>> {
+        let module = self.module;
+        let async_module = module.async_module();
+        let references = module.references();
+        let is_self_async = async_module
+            .resolve()
+            .await?
+            .is_self_async(references.resolve().await?)
+            .resolve()
+            .await?;
+        Ok(is_self_async)
+    }
 }

crates/turbopack-ecmascript/src/side_effect_optimization/facade/module.rs

@@ -40,14 +40,19 @@ impl EcmascriptModuleFacadeModule {
     }
 
     #[turbo_tasks::function]
-    pub fn async_module(self: Vc<Self>) -> Vc<AsyncModule> {
-        AsyncModule {
+    pub async fn async_module(self: Vc<Self>) -> Result<Vc<AsyncModule>> {
+        let import_externals =
+            if let Some(async_module) = *self.await?.module.get_async_module().await? {
+                async_module.await?.import_externals
+            } else {
+                false
+            };
+        Ok(AsyncModule {
             placeable: Vc::upcast(self),
-            references: self.references(),
             has_top_level_await: false,
-            import_externals: false,
+            import_externals,
         }
-        .cell()
+        .cell())
     }
 }
 

crates/turbopack-ecmascript/src/side_effect_optimization/locals/chunk_item.rs

@@ -39,12 +39,12 @@ impl EcmascriptChunkItem for EcmascriptModuleLocalsChunkItem {
         let chunking_context = self.chunking_context;
         let exports = self.module.get_exports();
         let original_module = module.module;
-        let async_module_options = original_module
-            .get_async_module()
-            .module_options(async_module_info);
         let parsed = original_module.parse().resolve().await?;
 
-        let analyze_result = original_module.analyze().await?.clone_value();
+        let analyze_result = original_module.analyze().await?;
+        let async_module_options = analyze_result
+            .async_module
+            .module_options(async_module_info);
 
         let module_type_result = *original_module.determine_module_type().await?;
 
@@ -55,6 +55,7 @@ impl EcmascriptChunkItem for EcmascriptModuleLocalsChunkItem {
             chunking_context,
             analyze_result.local_references,
             analyze_result.code_generation,
+            analyze_result.async_module,
             analyze_result.source_map,
             exports,
             async_module_info,
@@ -103,8 +104,11 @@ impl ChunkItem for EcmascriptModuleLocalsChunkItem {
 
     #[turbo_tasks::function]
     async fn is_self_async(&self) -> Result<Vc<bool>> {
-        if let Some(async_module) = *self.module.get_async_module().await? {
-            Ok(async_module.is_self_async())
+        let module = self.module.await?;
+        let analyze = module.module.analyze().await?;
+        if let Some(async_module) = *analyze.async_module.await? {
+            let is_self_async = async_module.is_self_async(analyze.local_references);
+            Ok(is_self_async)
         } else {
             Ok(Vc::cell(false))
         }

crates/turbopack-ecmascript/src/tree_shake/chunk_item.rs

@@ -10,8 +10,8 @@ use turbopack_core::{
 use super::{asset::EcmascriptModulePartAsset, part_of_module, split_module};
 use crate::{
     chunk::{
-        placeable::EcmascriptChunkPlaceable, EcmascriptChunkItem, EcmascriptChunkItemContent,
-        EcmascriptChunkType, EcmascriptChunkingContext,
+        EcmascriptChunkItem, EcmascriptChunkItemContent, EcmascriptChunkType,
+        EcmascriptChunkingContext,
     },
     EcmascriptModuleContent,
 };
@@ -40,15 +40,12 @@ impl EcmascriptChunkItem for EcmascriptModulePartChunkItem {
     ) -> Result<Vc<EcmascriptChunkItemContent>> {
         let this = self.await?;
         let module = this.module.await?;
-        let async_module_options = module
-            .full_module
-            .get_async_module()
-            .module_options(async_module_info);
 
         let split_data = split_module(module.full_module);
         let parsed = part_of_module(split_data, module.part);
 
         let analyze = this.module.analyze().await?;
+        let async_module_options = analyze.async_module.module_options(async_module_info);
 
         let module_type_result = *module.full_module.determine_module_type().await?;
 
@@ -59,6 +56,7 @@ impl EcmascriptChunkItem for EcmascriptModulePartChunkItem {
             this.chunking_context,
             analyze.references,
             analyze.code_generation,
+            analyze.async_module,
             analyze.source_map,
             analyze.exports,
             async_module_info,

crates/turbopack-tests/tests/execution.rs

@@ -32,6 +32,10 @@ use turbopack_core::{
     file_source::FileSource,
     issue::{Issue, IssueDescriptionExt},
     reference_type::{EntryReferenceSubType, ReferenceType},
+    resolve::{
+        options::{ImportMap, ImportMapping},
+        ExternalType,
+    },
     source::Source,
 };
 use turbopack_ecmascript_runtime::RuntimeType;
@@ -256,13 +260,20 @@ async fn run_test(prepared_test: Vc<PreparedTest>) -> Result<Vc<RunTestResult>>
         )
         .cell();
 
+    let mut import_map = ImportMap::empty();
+    import_map.insert_wildcard_alias(
+        "esm-external/",
+        ImportMapping::External(Some("*".to_string()), ExternalType::EcmaScriptModule).cell(),
+    );
+
     let asset_context: Vc<Box<dyn AssetContext>> = Vc::upcast(ModuleAssetContext::new(
         Vc::cell(HashMap::new()),
         compile_time_info,
         ModuleOptionsContext {
             enable_typescript_transform: Some(Default::default()),
             preset_env_versions: Some(env),
             tree_shaking_mode: options.tree_shaking_mode,
+            import_externals: true,
             rules: vec![(
                 ContextCondition::InDirectory("node_modules".to_string()),
                 ModuleOptionsContext {
@@ -290,6 +301,7 @@ async fn run_test(prepared_test: Vc<PreparedTest>) -> Result<Vc<RunTestResult>>
             )],
             browser: true,
             module: true,
+            import_map: Some(import_map.cell()),
             ..Default::default()
         }
         .cell(),