There has been a few issues in the past about TypeScript having problems generating correct results around CJS and default export. But those issues focus on certain aspect of the problem and I couldn't find one that clearly show how big an issue it is.
So I decided to give it a shot and it seems to be worse than I thought.
Here are a few TL;DRs:
When you use export default in your code:
- The declaration for CJS is incorrect.
When you consume a package that uses export default and transpiled to CJS:
module: ES* or Node*does not produce correct code (runtime error)
When using moduleResolution: Node16 or NodeNext:
- You cannot use
allowSyntheticDefaultImportsoresModuleInterop, which you must use inNodefor packages withexport =
Related issues:
microsoft/TypeScript#50501 microsoft/TypeScript#50152 microsoft/TypeScript#41898
- This is a crash
- This changed between versions ______ and _______
- This is the behavior in every version I tried, and I reviewed the FAQ for entries about _________
- I was unable to test this on prior versions because _______
Playground link with relevant code
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// - We have to pare too much extraneous code.
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