Add namespace re-export support to import-export plugin#1768
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Summary: Add static import/export plugin (`experimentalImportSupport`) support for namespace re-exports, i.e. `export * as Name from "module"`. This was added to Expo's fork in expo/expo#38055, (h/t krystofwoldrich). Despite this being perfectly valid syntax it currently fails to transform under `experimantalImportSupport`, with: ``` Cannot read properties of undefined (reading 'name') at <..>/metro-transform-plugins/src/import-export-plugin.js:289:67 ``` (On access of `local.name`, because this type of export has no `local` binding) ## Spec ECMA-262 includes namespace re-export syntax in the ExportDeclaration grammar: https://tc39.es/ecma262/#prod-ExportDeclaration ## Implementation Metro's existing `experimentalImportSupport` transform already has namespace import helper plumbing via `importAll`. This change reuses that helper and then emits an explicit export assignment for the namespace object, keeping the change isolated to the static transform path. ``` - **[Experimental]** Support `export * as Name from "module"` under `experimentalImportSupport` ``` Reviewed By: huntie Differential Revision: D111013905
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Summary:
Add static import/export plugin (
experimentalImportSupport) support for namespace re-exports, i.e.export * as Name from "module".This was added to Expo's fork in expo/expo#38055, (h/t @krystofwoldrich).
Despite this being perfectly valid syntax it currently fails to transform under
experimantalImportSupport, with:(On access of
local.name, because this type of export has nolocalbinding)Spec
ECMA-262 includes namespace re-export syntax in the ExportDeclaration grammar: https://tc39.es/ecma262/#prod-ExportDeclaration
Implementation
Metro's existing
experimentalImportSupporttransform already has namespace import helper plumbing viaimportAll. This change reuses that helper and then emits an explicit export assignment for the namespace object, keeping the change isolated to the static transform path.Reviewed By: huntie
Differential Revision: D111013905