[turbopack] Simplify JS ChunkItem with a single impl in most cases#89548
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| fn content(self: Vc<Self>) -> Vc<EcmascriptChunkItemContent> { | ||
| panic!("content() should not be called"); | ||
| fn get_exports(&self) -> Vc<EcmascriptExports> { | ||
| // Merged modules inherit exports from their entry points |
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so this wouldn't be correct
i think it is ok, but a bail or a panic might be more useful
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Yeah, should be a panic.
get_exports should never be called on merged modules
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i guess after seeing this i do wonder if a macro for implementing chunk_item would be the better solution. The tradeoff is really the chunk_item_content api vs the EcmascriptChunkItem trait implementation being customized
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ChunkItem with a single impl in most casesChunkItem with a single impl in most cases
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…thod
The ChunkableModuleReference trait was removed in this PR. References that
need to be chunkable now implement the chunking_type() method on
ModuleReference to return Some(ChunkingType::Parallel { ... }) instead.
bgw
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Feb 12, 2026
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What
Removes the vast majority of
ChunkItemimplementations in favour of oneEcmascriptModuleChunkItem.Why
Almost all of the
ChunkItemimplementations are trivial and were, for the most part, just places where additional traits could be implemented.By removing all of the various, trivial implementations, this might open up opportunities to better implement other features across the entire codebase.
How
Most chunk items are migrated over to EcmascriptModuleChunkItem. The EcmascriptChunkPlaceable trait gains three new methods that modules can optionally override:
chunk_item_content()- generates the chunk item's JavaScript codechunk_item_content_ident()- returns the content identity for cache invalidationchunk_item_output_assets()- returns output assets the chunk item depends onThe generic EcmascriptModuleChunkItem delegates to these trait methods, eliminating the need for per-module wrapper structs.
Next Steps
This exposes a fairly obvious next step, which is to elide
ChunkItemcompletely, as mostas_chunk_item()functions are now just trivial calls toecmascript_chunk_item(Vc::upcast(*self), module_graph, *chunking_context).