support tab completion cycling

[amtoine]

should close #7202

Description

i have been annoyed enough by this missing feature, so let's add that to Nushell without requiring any user configuration 😏

User-Facing Changes

this PR should allow tab completion cycling everytime, without requiring the user to use the default config files or add the following keybindings to their config

    {
        name: completion_menu
        modifier: none
        keycode: tab
        mode: [emacs vi_normal vi_insert]
        event: {
            until: [
                { send: menu name: completion_menu }
                { send: menunext }
                { edit: complete }
            ]
        }
    }

🧪 try it out

from the root of the repo, one can try <tab> in each of the following cases:

• cargo run -- -n to load Nushell without any config
• cargo run -- --config crates/nu-utils/src/sample_config/default_config.nu --env-config crates/nu-utils/src/sample_config/default_env.nu to load the default configuration
• cargo run to load the user configuration

before

• <tab>, ls <tab> and str <tab> only work with the second cargo run, i.e. when loading the default config files

after

• <tab> should cycle through the available commands
• ls <tab> should cycle through the available files and directories
• str <tab> should cycle the subcommands of str

in all three cases

Tests + Formatting

After submitting

[amtoine]

just amending the commit message, it was not... professional 👀 😆

[fdncred]

If you're going to enable tab, you should probably also enable shift-tab to go backwards through the list.

  {
    name: completion_menu_previous
    modifier: shift
    keycode: backtab
    mode: [emacs vi_normal vi_insert]
    event: { send: menuprevious }
  }

[amtoine]

@fdncred
i think it's already there 😋

https://github.com/nushell/nushell/blob/af79eb294/crates/nu-utils/src/sample_config/default_config.nu#L340-L346

https://github.com/nushell/nushell/blob/af79eb294/crates/nu-cli/src/reedline_config.rs#L485-L489

[fdncred]

@amtoine ah, ok. thanks. seems odd that we'd have shift-tab and not tab. probably an oversight on our part. i'm good with landing this.

[fdncred]

Thanks!

[amtoine]

ah, ok. thanks. seems odd that we'd have shift-tab and not tab. probably an oversight on our part. i'm good with landing this.

might have splitted through my config sync PR 👀