vercel · sokra · Mar 19, 2025 · Mar 18, 2025 · Mar 18, 2025 · Mar 18, 2025
diff --git a/turbopack/crates/turbopack-css/src/chunk/mod.rs b/turbopack/crates/turbopack-css/src/chunk/mod.rs
@@ -4,6 +4,7 @@ pub mod source_map;
 use std::fmt::Write;
 
 use anyhow::{bail, Result};
+use swc_core::common::pass::Either;
 use turbo_rcstr::RcStr;
 use turbo_tasks::{
     FxIndexSet, ResolvedVc, TryFlatJoinIterExt, TryJoinIterExt, Value, ValueDefault, ValueToString,
@@ -218,19 +219,23 @@ impl OutputChunk for CssChunk {
             .into_iter()
             .flatten()
             .collect();
-        let module_chunks = content
-            .chunk_items
-            .iter()
-            .chain(imports_chunk_items.iter())
-            .map(|item| {
-                Vc::upcast::<Box<dyn OutputAsset>>(SingleItemCssChunk::new(
-                    *self.chunking_context,
-                    **item,
-                ))
-                .to_resolved()
-            })
-            .try_join()
-            .await?;
+        let module_chunks = if entries_chunk_items.len() > 1 {
+            content
+                .chunk_items
+                .iter()
+                .chain(imports_chunk_items.iter())
+                .map(|item| {
+                    Vc::upcast::<Box<dyn OutputAsset>>(SingleItemCssChunk::new(
+                        *self.chunking_context,
+                        **item,
+                    ))
+                    .to_resolved()
+                })
+                .try_join()
+                .await?
+        } else {
+            Vec::new()
+        };
         Ok(OutputChunkRuntimeInfo {
             included_ids: Some(ResolvedVc::cell(included_ids)),
             module_chunks: Some(ResolvedVc::cell(module_chunks)),
@@ -310,21 +315,24 @@ impl OutputAsset for CssChunk {
         let this = self.await?;
         let content = this.content.await?;
         let mut references = content.referenced_output_assets.owned().await?;
+        let single_item_chunks = content.chunk_items.len() > 1;
         references.extend(
             content
                 .chunk_items
                 .iter()
                 .map(|item| async {
-                    Ok(item
-                        .references()
-                        .await?
-                        .into_iter()
-                        .copied()
-                        .chain(std::iter::once(ResolvedVc::upcast(
-                            SingleItemCssChunk::new(*this.chunking_context, **item)
-                                .to_resolved()
-                                .await?,
-                        ))))
+                    let references = item.references().await?.into_iter().copied();
+                    Ok(if single_item_chunks {
+                        Either::Left(
+                            references.chain(std::iter::once(ResolvedVc::upcast(
+                                SingleItemCssChunk::new(*this.chunking_context, **item)
+                                    .to_resolved()
+                                    .await?,
+                            ))),
+                        )
+                    } else {
+                        Either::Right(references)
+                    })
                 })
                 .try_flat_join()
                 .await?,

diff --git a/turbopack/crates/turbopack-css/src/chunk/single_item_chunk/chunk.rs b/turbopack/crates/turbopack-css/src/chunk/single_item_chunk/chunk.rs
@@ -106,7 +106,7 @@ impl OutputAsset for SingleItemCssChunk {
             self.item
                 .asset_ident()
                 .with_modifier(single_item_modifier()),
-            ".css".into(),
+            ".single.css".into(),
         )
     }
 

diff --git a/...mport_input_withduplicateurl_63c923ab.css → ...ithduplicateurl_css_b7298ed4._.single.css b/...mport_input_withduplicateurl_63c923ab.css → ...ithduplicateurl_css_b7298ed4._.single.css
diff --git a/...t_input_withduplicateurl_63c923ab.css.map → ...uplicateurl_css_b7298ed4._.single.css.map b/...t_input_withduplicateurl_63c923ab.css.map → ...uplicateurl_css_b7298ed4._.single.css.map
diff --git a/...olute-uri-import_input_index_63c923ab.css → ...ort_input_index_css_b7298ed4._.single.css b/...olute-uri-import_input_index_63c923ab.css → ...ort_input_index_css_b7298ed4._.single.css
diff --git a/...e-uri-import_input_index_63c923ab.css.map → ...input_index_css_b7298ed4._.single.css.map b/...e-uri-import_input_index_63c923ab.css.map → ...input_index_css_b7298ed4._.single.css.map
diff --git a/...tput/b1abf_turbopack-tests_tests_snapshot_css_absolute-uri-import_input_index_d95a0601.js b/...tput/b1abf_turbopack-tests_tests_snapshot_css_absolute-uri-import_input_index_d95a0601.js
diff --git a/...olute-uri-import_input_other_63c923ab.css → ...ort_input_other_css_b7298ed4._.single.css b/...olute-uri-import_input_other_63c923ab.css → ...ort_input_other_css_b7298ed4._.single.css
diff --git a/...e-uri-import_input_other_63c923ab.css.map → ...input_other_css_b7298ed4._.single.css.map b/...e-uri-import_input_other_63c923ab.css.map → ...input_other_css_b7298ed4._.single.css.map
diff --git a/...s_chained-attributes_input_a_dfbefa7d.css → ...ributes_input_a_css_43ef0703._.single.css b/...s_chained-attributes_input_a_dfbefa7d.css → ...ributes_input_a_css_43ef0703._.single.css
diff --git a/...ained-attributes_input_a_dfbefa7d.css.map → ...tes_input_a_css_43ef0703._.single.css.map b/...ained-attributes_input_a_dfbefa7d.css.map → ...tes_input_a_css_43ef0703._.single.css.map
diff --git a/...s_chained-attributes_input_b_8e58864e.css → ...ributes_input_b_css_5e695b86._.single.css b/...s_chained-attributes_input_b_8e58864e.css → ...ributes_input_b_css_5e695b86._.single.css
diff --git a/...ained-attributes_input_b_8e58864e.css.map → ...tes_input_b_css_5e695b86._.single.css.map b/...ained-attributes_input_b_8e58864e.css.map → ...tes_input_b_css_5e695b86._.single.css.map
diff --git a/...s_chained-attributes_input_c_63abd510.css → ...ributes_input_c_css_50ab7d84._.single.css b/...s_chained-attributes_input_c_63abd510.css → ...ributes_input_c_css_50ab7d84._.single.css
diff --git a/...ained-attributes_input_c_0d2bbfce.css.map → ...tes_input_c_css_50ab7d84._.single.css.map b/...ained-attributes_input_c_0d2bbfce.css.map → ...tes_input_c_css_50ab7d84._.single.css.map
diff --git a/...s_chained-attributes_input_c_0d2bbfce.css → ...ributes_input_c_css_ed320740._.single.css b/...s_chained-attributes_input_c_0d2bbfce.css → ...ributes_input_c_css_ed320740._.single.css
diff --git a/...ained-attributes_input_c_63abd510.css.map → ...tes_input_c_css_ed320740._.single.css.map b/...ained-attributes_input_c_63abd510.css.map → ...tes_input_c_css_ed320740._.single.css.map
diff --git a/...utput/b1abf_turbopack-tests_tests_snapshot_css_chained-attributes_input_index_81ab1477.js b/...utput/b1abf_turbopack-tests_tests_snapshot_css_chained-attributes_input_index_81ab1477.js
diff --git a/...ained-attributes_input_style_63c923ab.css → ...tes_input_style_css_b7298ed4._.single.css b/...ained-attributes_input_style_63c923ab.css → ...tes_input_style_css_b7298ed4._.single.css
diff --git a/...d-attributes_input_style_63c923ab.css.map → ...input_style_css_b7298ed4._.single.css.map b/...d-attributes_input_style_63c923ab.css.map → ...input_style_css_b7298ed4._.single.css.map
diff --git a/...utput/b1abf_turbopack-tests_tests_snapshot_css_css-legacy-nesting_input_index_d1e6b0db.js b/...utput/b1abf_turbopack-tests_tests_snapshot_css_css-legacy-nesting_input_index_d1e6b0db.js
@@ -1,6 +1,6 @@
 (globalThis.TURBOPACK = globalThis.TURBOPACK || []).push([
     "output/b1abf_turbopack-tests_tests_snapshot_css_css-legacy-nesting_input_index_d1e6b0db.js",
     {},
-    {"otherChunks":[{"path":"output/b1abf_turbopack-tests_tests_snapshot_css_css-legacy-nesting_input_style_da464693.css","included":["[project]/turbopack/crates/turbopack-tests/tests/snapshot/css/css-legacy-nesting/input/style.css [test] (css)"],"moduleChunks":["output/b1abf_turbopack-tests_tests_snapshot_css_css-legacy-nesting_input_style_63c923ab.css"]},"output/b1abf_turbopack-tests_tests_snapshot_css_css-legacy-nesting_input_index_49d4edb8.js"],"runtimeModuleIds":["[project]/turbopack/crates/turbopack-tests/tests/snapshot/css/css-legacy-nesting/input/index.js [test] (ecmascript)"]}
+    {"otherChunks":[{"path":"output/b1abf_turbopack-tests_tests_snapshot_css_css-legacy-nesting_input_style_da464693.css","included":["[project]/turbopack/crates/turbopack-tests/tests/snapshot/css/css-legacy-nesting/input/style.css [test] (css)"]},"output/b1abf_turbopack-tests_tests_snapshot_css_css-legacy-nesting_input_index_49d4edb8.js"],"runtimeModuleIds":["[project]/turbopack/crates/turbopack-tests/tests/snapshot/css/css-legacy-nesting/input/index.js [test] (ecmascript)"]}
 ]);
 // Dummy runtime
diff --git a/...tput/b1abf_turbopack-tests_tests_snapshot_css_css-legacy-nesting_input_style_63c923ab.css b/...tput/b1abf_turbopack-tests_tests_snapshot_css_css-legacy-nesting_input_style_63c923ab.css
diff --git a/.../b1abf_turbopack-tests_tests_snapshot_css_css-legacy-nesting_input_style_63c923ab.css.map b/.../b1abf_turbopack-tests_tests_snapshot_css_css-legacy-nesting_input_style_63c923ab.css.map
diff --git a/...utput/4e721_crates_turbopack-tests_tests_snapshot_css_css-modules_input_index_ecc05e48.js b/...utput/4e721_crates_turbopack-tests_tests_snapshot_css_css-modules_input_index_ecc05e48.js
diff --git a/...tput/b1abf_turbopack-tests_tests_snapshot_css_css-modules_input_style_module_63c923ab.css b/...tput/b1abf_turbopack-tests_tests_snapshot_css_css-modules_input_style_module_63c923ab.css
diff --git a/.../b1abf_turbopack-tests_tests_snapshot_css_css-modules_input_style_module_63c923ab.css.map b/.../b1abf_turbopack-tests_tests_snapshot_css_css-modules_input_style_module_63c923ab.css.map
diff --git a/...s/css/output/08d19_foo_style_63c923ab.css → ...08d19_foo_style_css_b7298ed4._.single.css b/...s/css/output/08d19_foo_style_63c923ab.css → ...08d19_foo_style_css_b7298ed4._.single.css
diff --git a/...s/output/08d19_foo_style_63c923ab.css.map → ...9_foo_style_css_b7298ed4._.single.css.map b/...s/output/08d19_foo_style_63c923ab.css.map → ...9_foo_style_css_b7298ed4._.single.css.map
diff --git a/...utput/08d19_foo_style_module_63c923ab.css → ...oo_style_module_css_b7298ed4._.single.css b/...utput/08d19_foo_style_module_63c923ab.css → ...oo_style_module_css_b7298ed4._.single.css
diff --git a/...t/08d19_foo_style_module_63c923ab.css.map → ...tyle_module_css_b7298ed4._.single.css.map b/...t/08d19_foo_style_module_63c923ab.css.map → ...tyle_module_css_b7298ed4._.single.css.map
diff --git a/...21_crates_turbopack-tests_tests_snapshot_css_css_input_imported_css_b7298ed4._.single.css b/...21_crates_turbopack-tests_tests_snapshot_css_css_input_imported_css_b7298ed4._.single.css
diff --git a/...t_css_css_input_imported_63c923ab.css.map → ...ut_imported_css_b7298ed4._.single.css.map b/...t_css_css_input_imported_63c923ab.css.map → ...ut_imported_css_b7298ed4._.single.css.map
diff --git a/...pshot_css_css_input_imported_446aabbc.css → ..._input_imported_css_d740de60._.single.css b/...pshot_css_css_input_imported_446aabbc.css → ..._input_imported_css_d740de60._.single.css
diff --git a/...t_css_css_input_imported_446aabbc.css.map → ...ut_imported_css_d740de60._.single.css.map b/...t_css_css_input_imported_446aabbc.css.map → ...ut_imported_css_d740de60._.single.css.map