next.js

e78d35b3 - Fix react-loadable-manifest chunk hash mismatch by preserving async loader mapping (#88775)

Fix react-loadable-manifest chunk hash mismatch by preserving async loader mapping (#88775) ## What? Fixes a bug where `react-loadable-manifest.json` in Turbopack dev mode contained references to chunk files with wrong hashes, causing 404 errors when loading dynamic imports. ## Why? When using `next/dynamic` with nested imports (e.g., a dynamic component that itself imports other modules), the chunk files referenced in `react-loadable-manifest.json` had different hashes than the actual generated chunk files. The root cause was that `collect_next_dynamic_chunks` was **recomputing** chunk content that was already computed by `make_chunk_group`. This pattern was inherently brittle because Next.js code had to carefully mirror Turbopack's internal chunking logic to get consistent hashes. This brittleness was exposed when the `turbopackClientSideNestedAsyncChunking` feature was disabled in dev mode (released in 16.1). The subtle differences in how availability info was computed led to hash mismatches. ## How? Instead of recomputing chunks for next/dynamic imports, this PR preserves the module→async loader mapping from when chunks are first computed in `make_chunk_group`, and looks up pre-computed chunks directly. This eliminates the need for Next.js to replicate Turbopack's chunking logic. ### Key changes: 1. **Extended `MakeChunkGroupResult` and `ChunkGroupResult`** with `async_loaders_by_module` field - Maps `ResolvedVc<Box<dyn ChunkableModule>>` → `ResolvedVc<Box<dyn ChunkItem>>` - Preserves the module→loader relationship computed during chunking 2. **Eliminated redundancy** in `MakeChunkGroupResult` - Removed the separate `references` field (was just upcasted async loaders) - Added `references()` method that derives references on-demand from the map 3. **Simplified `collect_next_dynamic_chunks`** - Now performs simple lookup instead of recomputation - Removed `module_graph` and `chunking_context` parameters - Uses `NextDynamicChunkAvailability` enum to access pre-computed chunk groups 4. **Added regression test** to verify chunk files referenced in manifest exist ### Files modified: - `turbopack/crates/turbopack-core/src/chunk/chunk_group.rs` - Add mapping, remove redundant field - `turbopack/crates/turbopack-core/src/chunk/chunking_context.rs` - Extend ChunkGroupResult - `turbopack/crates/turbopack-browser/src/chunking_context.rs` - Pass through mapping - `turbopack/crates/turbopack-nodejs/src/chunking_context.rs` - Pass through mapping - `crates/next-api/src/dynamic_imports.rs` - Lookup instead of recompute - `crates/next-api/src/pages.rs` - Updated caller - `crates/next-api/src/app.rs` - Updated caller - `crates/next-core/src/next_app/app_client_references_chunks.rs` - Initialize empty map Fixes #87680