When using Vim I had to learn how to configure saving behavior, because this can have important semantic implications if you edit soft or hard links — see docs for the backupcopy option. The two options describe how to save while creating a backup:
- make a copy of the file and overwrite the original one
- rename the file and write a new one
Docs contain examples where either behavior is needed:
[If creating the backup file by renaming the original] A program that opens a file, invokes Vim to edit that file, and then tests if the open file was changed (through the file descriptor) will check the backup file instead of the newly created file. “crontab -e” is an example.
This [Breaking symbolic or hard links] can be useful for example in source trees where all the files are symbolic or hard links and any changes should stay in the local source tree, not be propagated back to the original source.
Those use cases require an editor with specific behavior, so Atom should choose whether it wants to support them — possibly by allowing plugins to choose.