In fish, suggested autocompletions are contextual. For example, if I am in /home/dual_basis/projectA and I type `cd some/subdir` then a bunch of time goes by when I come back to /home/dual_basis/projectA and start typing `cd` it will suggest `cd some/subdir`, even if I have typed a bunch of other `cd` commands while in other directories.

This isn't specific to `cd` commands either. It's useful if you are `rsync`ing different directories to different places, or checkout different `git` branches, etc.