prompt shows ... if there are emojis in item output or directory names

[mknj]

Describe the bug

The beginning of the prompt is messed up if there are emojis in the prompt line

Steps to reproduce

Run mkdir "dirname containing emoji (🐛)"; cd dir*

Expected behavior

The first character of the prompt does not change

Screenshots

Environments

• Microsoft WSL running "18.04.1 LTS (Bionic Beaver)" + Microsoft Terminal
• Ubuntu 20.10 + gnome-terminal

fish, version 3.2.1
tide, version 4.3.2
xterm-256color

Additional context

This is really annoying if you try to put colored emojis in your item. i.e.

[mknj]

The ellipsis vanishes when resizing the window, but it is displayed again when entering commands.

[IlanCosman]

The problem is that I've been using string length as a proxy for string width.

@faho Could you help me out?

function foo -a char
    set -l stringLength (string length "$char")
    
    echo $stringLength
    
    printf '%s' $char
    string repeat --max (math $COLUMNS - $stringLength) -
end

Is there any way to have string length use the values of fish_emoji_width/fish_ambiguous_width? Or otherwise calculate the width of a string?

[faho]

Is there any way to have string length use the values of fish_emoji_width/fish_ambiguous_width? Or otherwise calculate the width of a string?

No. It's length, not width. fish-shell/fish-shell#4012 asks for a string width subcommand.