Dynamic `import()` in a CJS file can execute a module twice about tsx HOT 3 OPEN

This is definitely unexpected.

What's happening is the first import statement gets converted to require(), and since require can't load Module (.mjs) files, it transforms them to CommonJS so it can be. The second dynamic import() remains untouched.

So the first and second files are technically different modules, where the first one is dynamically derived on demand.

This is a technical limitation but it will be resolved once nodejs/node#51977 lands

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I understand that you keep the dynamic import, but since it’s using mts behind, it means that at some point tsx get to transpile it "again" right? So in this instance you do transpile it as an ESM module instead of as a CJS modules as the first time right? Could you not detect that it was previously loaded as a CJS and return the CJS version instead (since node do support import() on CJS files)? Or return to node a fake module that does export the required CJS module?

Even waiting for nodejs/node#51977 would not really resolve the issue since this patch does not support requiring modules with top level async in them.

Replacing the import() with a require() implicitely would end badly for a lot of files.
And if you replace it with a try/catch to fallback to import(), then the bug I'm reporting would still be there for those.

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I'm not sure, but feel free to give it a tackle. I'd be happy to review the PR!

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