Fish Shell 4.2 enhances history-based autosuggestions, defaults to UTF-8 encoding, clears transient prompts correctly, and more.

Fish shell, a popular user-friendly command-line shell, has announced version 4.2, a new release that builds on the 4.0 series. Among the most visible improvements is an upgrade to history-based autosuggestions, which now properly handle multi-line commands.

Fish 4.2 also improves how prompts are managed: transient prompts that contain more lines than the final one are now cleared properly, preventing visual clutter on screen. Similarly, the shell now hides parts of a multi-line prompt that have scrolled out of view, eliminating duplicated lines after repainting.

  • Oinks@lemmy.blahaj.zone
    9·
    8 hours ago

    This is by no means complete, but the features that I value would be:

    • <Tab> cycles though completions as it should instead of duplicating the prompt.
    • Completions also show help text (if there’s a provider for one). For example on git <Tab> it shows a short message describing what the command does. JJ goes further: jj diff -r <Tab> shows part of the commit message for the offered commits.
    • There are just more completions than in any other shell I know. Aside from JJ the new Nix CLI also has great Fish completions and can dynamically complete flake outputs like package names.
    • Entire commands can be history completed with <C-E> or <Right>. This completion is also directory-aware and can usually avoid suggesting commands with paths to files that don’t exist. In practice I find that it’s really good at suggesting the command I actually want to run, to the point that I rarely invoke FZF anymore.
    • Abbreviations are in most cases better aliases since they do the same thing but don’t obscure what you’re actually running.
    • No word splitting when expanding variables, because it’s never what you intended.
    • Globs that fail to match anything are errors instead of silently doing the wrong thing.
    • Control structures are a bit nicer (but that is subjective).

    You can get most of these with liberal use of shell options, installing blesh, or alternatively installing zsh with a bunch of plugins, but Fish just has all of them out of the box. You don’t even need bash-completions.

    how hard is it to transition?

    It has a reputation of being very difficult from the past when it didn’t have &&/|| but I think today plenty of Linux users would not even notice. The most notable remaining differences are setting variables (requires the set builtin unless used to modify the environment for a single command), control structures (irrelevant in interactive use) and lack of !! (but you can make an abbreviation to bring it back).