How to configure for bash-style partial completion?

[Martin Gill (MartinSGill)]

I'm trying to figure out how/if it's possible to configure PSReadline for the way default bash seems to handle completions.

Current behaviour is that when I press to complete it inserts the first item found at the prompt (e.g. the first file in the directory). I've tried setting tab to MenuComplete, but all that does is present options, it doesn't fill the prompt with as much as it can.

What I want is for it to insert as much common text as it can and then presenting options.

e.g. if I have

ProjectA.SomeThing
ProjectA.SomeOtherThing
ProjectB.SomeOtherThing

• > Pr<tab> --> > Project|
• > ProjectA<tab> --> > ProjectA.Some|

What combination of settings do I need for this behaviour?

[PhantomBugz (PhantomBugz)]

Bind Tab to Complete:

Set-PSReadLineKeyHandler -Key Tab -Function Complete

Complete first extends the input to the shared prefix. Pressing Tab again at that point lists the possible completions. Windows mode normally binds Tab to TabCompleteNext, which cycles through whole candidates; MenuComplete opens the selectable menu.

I checked with directories named ProjectA.SomeThing, ProjectA.SomeOtherThing, and ProjectB.SomeOtherThing:

Get-Item Pr<Tab>        -> Get-Item .\Project
Get-Item ProjectA<Tab>  -> Get-Item .\ProjectA.Some

A second Tab lists the matching directories. You can keep Ctrl+Space bound to MenuComplete and use Tab for this prefix-first behavior; changing the entire editing mode isn't necessary. Add the binding line to your PowerShell profile if you want it in future sessions.

Tested interactively on Windows with PowerShell 7.6.9 and PSReadLine 2.4.5.

Reference: PSReadLine completion functions.

AI-assisted reply; the completion behavior above was checked in a separate local session.