Using flow as the editor for chezmoi edit fails to save changes with chezmoi hardlinks enabled

[nurpax]

I've set flow as the EDITOR in my shell config.

I noticed that the dotfile management tool chezmoi by default uses hardlinks in such a way, that running chezmoi edit <some config file> opens the config file correctly but saving the file does nothing. I.e., I hit ctrl+s in flow but no changes are saved into the edited file.

The same doesn't happen if I do EDITOR=emacs chezmoi edit. I notice that I can also make it work with flow if I do chezmoi edit --hardlink=false <some file>. The docs for the hardlink feature state:

Invoke the editor with a hard link to the source file with a name matching the target filename. This can help the editor determine the type of the file correctly. This is the default.

(https://www.chezmoi.io/reference/commands/edit/)

I wonder why does flow behave this way with hardlinks?

[neurocyte]

Flow does atomic file writes, which basically means it writes a new file and then moves the fully written file to the final location, thus instantly replacing the file in an atomic operation. Many editors work this way because it guarantees that you never write half a file. (Which can typically happen easily if your file system is nearly full for example)

This by definition means that flow will break hard links, but flow supports writing through symlinks since 0.7 now, so you can just use a symlink instead. (which is commonly the preferred solution anyway)

[nurpax]

Thank you very much! This makes sense and I agree that the atomic replace is the way to go.

I think I'll just keep hardlinks disabled for chezmoi edit (it's a config option, fortunately), it's a little unclear why the hardlink is needed and maybe that's an unsafe default to use anyway.