refactor(es/module): Align module transform records with spec terms - #11992
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**Description:** <!-- Explain the **motivation** for making this change. What existing problem does the pull request solve? --> Rewrites the SystemJS module transform around a structured lowering/emission pipeline. This preserves SystemJS live bindings across imported re-exports, exported local mutations, destructuring assignments, update expressions, and `for-in` / `for-of` heads. It also keeps `export default class` evaluation order inside `execute` and emits import attribute metadata for System.register dependencies. Note: this PR is currently stacked on #11992, a related refactor PR. The SystemJS changes here do not semantically depend on it, but the branch is based on that work for now. **Related issue:** - Closes: #4895 - Closes: #5288 - Closes: #5649 - Closes: #6986 - Closes: #8122 - Closes: #8123
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Description:
This PR refactors the shared CommonJS/AMD/UMD module-lowering collection layer to use terminology and boundaries closer to ECMAScript module records.
The old
ModuleDeclStripabstraction mixed declaration stripping, module request collection, export collection, and emitter-facing naming. This change renames and reshapes that layer intomodule_record.rswith clearer concepts:ModuleRecordCollectorRequestedModules/RequestedModuleModuleRecordEntryModuleRequestUsageLocalExportEntriesModuleRecordEntryReducerExportBindingCJS, AMD, and UMD now consume the same module-record-oriented data model while preserving their existing emit behavior. The format-specific passes still own wrapper shape, dependency emission, interop helper application,
export =handling, and import-reference rewriting.This is intended to be a behavior-preserving refactor. The main goal is to make the transform pipeline easier to reason about and maintain before future module interop work.
The README was also expanded with diagrams and a short walkthrough of the transform flow.
Verification:
cargo fmt --allcargo test -p swc_ecma_transforms_modulecargo clippy --all --all-targets -- -D warningsBREAKING CHANGE:
None.
Related issue (if exists):
N/A