copySync empty folder into an existing file

[oldrich-s]

Copy an empty folder into an existing file. I would expect, an error should be thrown as the file cannot be overwritten by a folder. Since the folder is empty, no error is thrown and no folder is created. If the folder is not empty, ENOENT is thrown.

[RyanZim]

This behavior is consistent in both copy & copySync. The behavior does seem a little weird, though. To be honest, this is what I hate about copy; there are a million edge cases + always one more that you haven't thought of.

CC @jprichardson @manidlou for thoughts here; so far I haven't pinned down why it's doing this.

[RyanZim]

@jprichardson @manidlou ping?

[manidlou]

Yeah I also confirm the faulty behavior! However, I applied a possible fix for this issue in #502 that prevents this from happening. When rewriting copy is finished, then related changes will be applied to copySync as well since they need to be consistent.

[manidlou]

Fixed in 5.0.0 🎉