Fix requires of external CommonJS SWC helpers #8693
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Fixes a regression introduced by #8555. Reproduction
The root cause was that due to library mode rewriting SWC helpers for CJS libraries, the dep had a
placeholder: https://github.com/parcel-bundler/parcel/blob/v2/packages/transformers/js/core/src/dependency_collector.rs#L124-L125Then, when we build our dep map, we use the placeholder rather than the original specifier + "esm":
parcel/packages/transformers/js/src/JSTransformer.js
Lines 734 to 736 in 426852f
But when looking up the dep, we would still append "esm", leading no dep to be found and therefore no symbols replaced later on:
parcel/packages/transformers/js/src/JSTransformer.js
Lines 751 to 755 in 426852f
To fix this, I've changed the way this works so we don't append "esm" but instead use a placeholder for CJS deps on the rust side. This fixes the original issue where CJS and ESM imports for the same specifier wouldn't work, without needing additional metadata. To get that to work, I had to add specifiers for external modules to the dev packager so we remap from the placeholder to the original specifier when requiring them.