allowSyntheticDefaultImports not respected for `export { default as Foo } from "./b"`

[andrewbranch]

Acknowledgement

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Comment

After #62567, tests/cases/compiler/reexportMissingDefault4.ts and -5.ts should not have errors, since

• esModuleInterop/allowSyntheticDefaultImports defaults to true
• the target file is a declaration file

but they still error with the error that the target module b.d.ts has no default export. (While this error sounds reasonable, the rationale is that we don't know whether the declaration file corresponds to CommonJS or ESM under the circumstances, and if CommonJS, a default import is allowed to reference the whole module.exports symbol.) The bug is likely related to the export { default as Foo } from "./b" syntactic form, since reexportMissingDefault4.ts does export { default } from "./b" under similar settings and is correctly error-free.

[andrewbranch]

This is already the case, we were looking at an out of date submodule